When Adobe Photoshop Elements was first released one of the real bonuses of the program was the inclusion of the Photomerge technology. Designed to stitch together a series of overlapping images to form a wide vista print this feature really sets hearts racing amongst those of us with a secret passion for panoramas. There is just something about a long thin photograph that screams special to me. I have often dreamt of owning a camera capable of capturing such beauties, but alas the bank balance always seems to be missing the required amount that would be needed to make such a purchase.
And to be honest, the pragmatist in me also has to admit that the comparatively few shots that I would take in this format would not warrant the expense. It was in the midst of such thoughts a couple of years ago that I was first introduced to Photomerge, which has proven to be a solution to my ‘wide vista’ problems that suited both my budget and my infrequent production.
The feature combines several overlapping images to form a new wide angle photograph. Once in this form the panorama can be treated like any other Elements document, providing photographers with the ability to create truly stunning and interesting, wide and thin compositions.
Photomerge basics>> For those readers who are new to the feature, use the workflow in the table aside to guide you through making your first Photomerge panorama.
Once you are confident with creating simple wide vista images using the feature, work through the advanced techniques discussed in the rest of the chapter to refine your panoramic prowess.
The technology behind the ‘Image Stitching’ idea is simple. Shoot a range of images whilst gradually rotating a standard camera so that each photograph overlaps the next. Next, import the pictures into Elements and then Photomerge and proceed to stitch the images together to form a wide, no make that very wide, panoramic picture.
From here the photo could be printed, or if the original series of images covered the full 360° of the scene with the first and last pictures overlapping, a special ‘wrap-around view’, called virtual reality (VR) panorama, could be produced. Programs like Apple’s QuickTime use these 360° panoramas and allow the viewer to stand in the middle of the action and spin the image around. It is like you are actually there.
Despite the comparative ease with which Photomerge stitches images together the best quality panoramas are made when attention is paid to every step of the capture, stitch and print process. The following techniques go beyond the basic steps needed to create a panorama and will help you produce the best pictures possible with the Photomerge system.
Tips for great panoramas:
- Panoramas are first and foremost a photographic exercise. Composition, lighting and point of view are all critical, although they have to be dealt with differently to traditional photography.
- Elements is your friend. Use it to fix problem areas in your finished panorama.
- If possible use a special panorama head to capture your pictures. If you can’t afford a commercial model search the net for plans of a DIY version for your camera and lens combination.
Photomerge >> The Photomerge feature in Elements is specially designed to stitch together a series of overlapping pictures to form a panorama.
When producing great panoramas the importance of the photographic step in the process cannot be underestimated. It is here that much of the final quality of your VR scene is determined. A few extra minutes taken in the setting up and shooting phases will save a lot of time later sitting in front of the computer screen fixing problems.
Suitable for Elements – 5.0, 4.0, 3.0, 2.0, 2.0 | Difficulty level – Basic Related techniques – 9.02
Photographers have long prided themselves in their ability to compose the various elements of a scene so that the resultant picture is dynamic, dramatic and balanced. These aims are no less important when creating panoramic images, but the fact that these pictures are constructed of several separate photographs means that a little more thought needs to be given to the positioning of the camera in the scene. For the best results the photographer needs to try and pre-visualize how the final picture will appear once the single images are combined and then select the camera’s position.
Rule of thirds >> The same ideas of composition should be followed when making decisions about where to position the camera to capture a panorama sequence of pictures. To ensure that the resultant wide vista picture contains all the drama of a traditional photograph you should ensure that the foreground, mid ground and background details are all present in the final stitched picture.
One common mistake is to move to the center of the environment, set up the equipment and create a sequence of images with most of the subject detail in the mid or background of the picture. This type of panorama provides a good overview of the whole scene but will have little of the drama and compositional sophistication that a traditional picture with good interaction of foreground, mid ground and background details contains.
When deciding on where to position your camera sweep the area whilst looking through the viewfinder. Ensure that the arc of proposed images contains objects that are close to the camera, contrasted against those subjects that are further into the frame.
Camera positioning >> Unlike traditional photography the panoramic image-maker must pre-visualize how the stitched picture will appear when considering where to position the camera.
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Extend this compositional idea further by intentionally positioning the nearest and most dramatic objects in the scene one-third (or two-thirds) of the way into the sequence of images. This will provide balance to the photograph by positioning this point of focus according to the ‘rule of thirds’ in the final panorama. |
Suitable for Elements – 5.0, 4.0, 3.0, 2.0, 1.0 | Difficulty level – Intermediate | Related techniques – 9.01, 9.09
Though not essential for shooting the odd sequence of images, most panoramic professionals insist on using a tripod coupled with a special panoramic head to capture their pictures. The tripod provides a stable and level base for the camera; the panoramic head positions the camera and lens precisely over the pivot point of the tripod and also contains regular click stops to indicate points in the spin to capture a photograph. Each stop is designed to provide optimum coverage for each frame, taking into account the required edge overlap.
This set up increases the effectiveness of your stitching software’s ability to accurately blend the edges of your images. Companies like Kaidan (www.kaidan.com), Manfrotto (www.manfrotto.com) and Peace River Studios (www.peaceriverstudios.com) manufacture VR equipment specifically for particular cameras and lenses. You can purchase a tripod head designed specifically for your camera or choose a head that can be adjusted to suit any camera.
Why all this bother with specialized equipment? Photomerge’s main task is to seamlessly blend the edges of overlapping images. This is best achieved when the edge details of the two pictures are as similar as possible. Slight changes in the relationship of the objects in the scene will cause problems when stitching, often resulting in ‘ghosting’ of the objects in the final panorama. Now, for the occasional Photomerge user this is not too big a deal as a little deft work with your Elements editing tools and the picture is repaired (see technique 5.09), but frequent panorama producers will want to use a technique that produces better results faster. Using a special VR (virtual reality) or panoramic tripod head produces such results by positioning the ‘nodal point’ of the lens over the pivot point of the tripod. Images shot with this set up will have edges that match more evenly, which means that Photomerge can blend these overlapping images more successfully and accurately.
Panoramic tripod heads >> Specialized panoramic or VR (virtual reality) tripod heads are perfect for ensuring that the lens’ nodal point is over the pivot point of the tripod. This precision pays dividends at stitching time as Photomerge will produce much better results when the edges of sequential images can be exactly matched.(a) Adjustable Manfrotto VR head suitable for a range of cameras.(b)Camera-specific Kaidan head suitable for a single camera body only.
Finding the Nodal Point
If you have a VR head designed specifically for your camera and lens then the hard work is already complete. Simply set up the equipment according to the manufacturer’s instruction and you will be taking ‘nodal point correct’ pictures in no time. If, however, you are using a fully adjustable VR head or you just want to find the nodal point for a specific camera and lens combination you can use the following techniques as a guide.
Some camera or lens manufacturers provide details about the nodal points of their products but, on the whole, this type of data is hard to find and it is up to the shooter to determine the nodal point of his or her own equipment. For this the main method is usually referred to as the ‘lamp post’ test and is based on a two-step process. With the camera set up and levelled on a panoramic head use the step-by-step guide to find the nodal point.
If the lens’ nodal point is rotating over the tripod pivot point then the visual distance (gap) will remain the same throughout the movement. If the distance changes then the lens is not positioned correctly and needs to be moved either forwards or backwards to compensate.
With a little trial and error you should be able to locate the exact nodal point for each of your lenses, cameras and lens zoom points. VR tripod heads, like those made by Manfrotto, excel in this area. The fine-tuning controls and set up scales enable the user to accurately locate and note the position of the nodal points for a variety of lenses and/or cameras. With the tests complete the results should be recorded and used whenever the same camera set up is required again.
Left to right adjustment >> The lens and tripod should be viewed from the front and the lens position adjusted from left to right until it sits vertically above the tripod’s pivot point.
You can check your positioning skills by turning the camera 90° down (so that the lens faces the tripod pivot) and confirming that the pivot point is located centrally in the LCD Preview screen. This is the easy part.
Front to back adjustment >> Move the camera back and forward to find the nodal point of the lens. Set camera and tripod up so that there is a vertical object such as a lamp post or sign very near the camera and a similar vertical object in the distance. The closer the foreground object the more accurate the results of the test will be.
Watching the LCD Preview screen (or looking through the viewfinder in an SLR camera) rotate the camera and compare the distance between the foreground and background objects.
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If you don’t have a special panoramic head try rotating the camera around the lens rather than pivoting around your body. Also, if you are shooting ‘hand-held’ use longer focal lengths rather than wide angle lenses; this will help with stitching later. |
Nodal point errors >> Many stitching errors are the result of source images being shot with the camera and lens not being centered over the nodal point.
Handy Guide to Nodal Point Corrections
Use these rules to help you correct nodal point errors:
1. Moving the lens backwards: if rotating the camera away from the foreground object, increases the visual gap, or
2. Moving the lens forwards: if rotating the camera away from the foreground object, decreases the visual gap.
Suitable for Elements – 5.0, 4.0, 3.0, 2.0, 1.0 | Difficulty level – Basic | Related techniques – 2.03, 9.11
As the lighting conditions can change dramatically whilst capturing the sequence of images you need to make up a panorama, it is important that the camera’s exposure be set manually. Leaving the camera set to auto exposure (Program, Aperture priority or Shutter speed priority) will result in changes in brightness of sequential images, especially if you are capturing pictures throughout a full 360° sweep of the scene.
Manual exposure >> Set your camera to manual exposure to ensure consistency across the sequence of images.
Take readings from both the shadow and highlight areas in several sections of the environment before selecting an average exposure setting, or one that preserves important highlight or shadow detail. Lock this shutter speed and aperture combination into your camera and use the same settings for all the source images. If the scene contains massive changes in brightness this will mean that some parts of the picture are rendered pure white or pure black (with no details); so you may want to consider using the steps in technique 9.11 as a way of capturing more details in these areas. To ensure that you have sufficient picture data to complete the technique capture two or three complete sequences with varying exposures. The exposure for one sequence should be adjusted to record highlights; one for shadows and if required a third can be used to capture mid tones.
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Use your camera’s exposure bracketing system to shoot the over-, mid and underexposures automatically. |
Average exposure>> To help ensure that your exposure setting is suitable for all the source images take several readings from all over the scene and then change your camera to the average of these results.
Suitable for Elements – 5.0, 4.0, 3.0, 2.0, 1.0 | Difficulty level – Basic Related techniques – 9.05
A similar problem of differences from image to image can occur when your camera is set to auto-focus. Objects at different distances from the camera in the scene will cause the focus to change from shot to shot, altering the appearance of overlapping images and creating an uneven look in your final panorama. Switching to manual focus will mean that you can keep the point of focus consistent throughout the capture of the source images. In addition to general focus changes, the zoom setting (digital or optical) for the camera should not be changed throughout the shooting sequence either.
Manual focus>> Switch your camera to manual focus and then set the distance to encompass the subjects in the scene taking into account ‘depth of field’ effects as well.
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When setting your focus also consider the depth of field that you desire for the image. |
Suitable for Elements – 5.0, 4.0, 3.0, 2.0, 1.0 | Difficulty level – Basic | Related techniques – 9.04
Despite the fact that cameras can only focus on one part of a scene at a time (focus point) most of us have seen wonderful landscape images that look sharp from the nearest point in the picture right through to the horizon. Employing a contrasting technique, many contemporary food books are filled with highly polished pictures where little of the shot is sharp. I’m sure that you have seen images where only one tiny basil leaf is defined whilst the rest of the food and indeed the plate is out of focus. Clearly focusing doesn’t tell the whole sharpness story.
This phenomenon of changing degrees of sharpness in a picture is referred to as the ‘depth of field of acceptable sharpness’ or ‘DOF’. When shooting panoramas it is important to know the factors that control this range of sharpness and, more importantly, how to control them.
Focus and DOF >> Ensure that you consider focus and depth of field at the same time, as both these variables will affect the subject sharpness in your source images.
(a) Sharp foreground detail.
(b) Background unsharp due to shallow DOF.
DOF is controlled by three distinct photographic variables:
Aperture – Changing the aperture, or F-Stop number, is the most popular technique for controlling depth of field. When a high aperture number like F32 or F22 is used, the picture will contain a large depth of field – this means that objects in the foreground, mid ground and background of the image all appear sharp. If, instead, a low aperture number is selected (F1.8 or F2), then only a small section of the image will appear focused, producing a shallow DOF effect.
Focal length – The focal length of the lens that you use to photograph also determines the extent of the depth of field in an image. The longer the focal length (more than 50 mm on a 35 mm camera) the smaller the depth of field will be, the shorter the focal length (less than 50 mm on a 35 mm camera) the greater DOF effect.
Distance from the subject – The distance the camera is from the subject is also an important depth of field factor. Close-up, or macro photos, have very shallow DOF, whereas landscape shots where the main parts of the image are further away have a greater DOF. In other words the closer you are to the subject, despite the aperture or lens you select, the shallower the DOF will be in the photographs you take.
Aperture and DOF >> Most photographers turn to their aperture control first when they want to change the depth of field of sharpness in their images. (a)A small aperture number produces pictures with a shallow depth of field. (b)Selecting a large aperture number produces a larger depth of field.
As most panoramic pictures require sharp details in the foreground, mid and background you should practise setting up your camera for the largest depth of field possible. This means selecting a high aperture number, wide angle lenses and increased camera-to-subject distances wherever possible. It is also good practice to take a couple of test shots of sections of the scene and review these on the LCD monitor on the back of the camera (using the magnification option) to ensure that you have sharpness in the areas of the picture that you desire.
Use the table below as a quick guide for setting up your camera for either shallow or large depth of field effects.
Suitable for Elements – 5.0, 4.0, 3.0, 2.0, 1.0 | Difficulty level – Basic Related techniques – 2.07
As we have already seen in Chapter 2 the White Balance feature assesses not the amount of light entering the camera, but the color, in order to automatically rid your images of color casts that result from mixed light sources. Leaving this feature set to ‘auto’ can mean drastic color shifts from one frame to the next as the camera attempts to produce the most neutral result. Switching to manual will produce images that are more consistent but you must assess the scene carefully to ensure that you base your white balance settings on the most prominent light source in the environment.
For instance if you are photographing an indoors scene that combines both daylight through a window and domestic lights hanging from the ceiling then the Auto White Balance feature will alter the color of the captured images throughout the sequence. Switching to manual will allow you to set the balance to match either of the two light sources or even a combination of both using the preset feature (see technique 2.07).
White balance errors >> Shooting with your camera set to the auto white balance setting can cause inconsistent color between sequential source images. Switching your camera to a mode that suits the dominant light source for the scene will produce more even results.
Suitable for Elements – 5.0, 4.0, 3.0, 2.0, 1.0 Difficulty level – Basic Related techniques – 9.09
Though not strictly a photographic technique, timing is very important when photographing your sequence of images. Objects that move in the frame or are positioned at the edges of one picture and not the next cause stitching problems when Photomerge tries to blend the edges. The best approach to solving this problem is to wait until the subjects have moved through the frame before capturing the image. A similar solution can be used when photographing in changing lighting conditions. For instance, if you start to capture a sequence of images in full sunshine only to find that halfway through a rouge cloud shadows the scene, then it is best to wait until the sun is shining again before recommencing the capture.
Timing errors >> Try to time your exposures so that you limit subject changes at the edges of your pictures.
Even though I present some editing techniques later in the chapter that will help you rectify these types of problems the best solution is always to try and capture the most accurate and error-free sequence of source images. In this situation ‘prevention is better than cure’ and definitely more time efficient as well.
9.08 Ensuring Consistent Overlap
Suitable for Elements – 5.0, 4.0, 3.0, 2.0, 1.0 Difficulty level – Basic
As you are capturing, ensure that the edges of sequential images are overlapping by between 15 and 40%. The exact number of images needed to complete the sweep of the vista or the full circle will depend on the angle of view of the lens as well as the amount of overlap that you have used.
A quick way of calculating the pictures needed for 30% overlap is to count the number of images required to complete a full 360° rotation with no overlap and then multiply this value by 3. Or, alternatively, you can use the recommendations detailed in the table below as a starting point for the number of overlap portrait images required to construct a 360° panorama.
Click-stop heads >> To evenly space sequential image capture points and ensure consistent overlap some companies like Kaidan (www.kaidan.com) produce panorama tripod heads with a built-in ‘click-stop’ system. The number of stop points is dependent on the angle of view of the lens used to capture the source pictures.
(a) Rotating the camera and stopping to capture picture.
(b) A variety of click-stop disks designed for use with different camera lenses or zoom settings
Professional VR heads ensure overlap consistency by placing ‘click-stops’ at regular points on the circumference of the head. On many models this is a variable feature that allows the photographer to change the interval to suit different lenses and/or overlapping amounts. Those on a more modest budget can mark regular intervals on their tripod head using a protractor or use the grid within the camera’s viewfinder as a guide.
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Some cameras now provide a special Panorama mode that ghosts the previous shot in the LCD screen so that you can line up or overlap the next picture accurately. |
| Focal length in mm (35 mm equivalent ) | Number of images required for 360° panorama |
| 14 | 12 |
| 18 | 12 |
| 20 | 12 |
| 24 | 18 |
| 28 | 18 |
| 35 | 20 |
| 42 | 24 |
| 50 | 28 |
Number of images for 360˚ >> Use the table above to calculate the number of overlapping pictures you will need to capture to create a 360˚ panorama.
9.09 Dealing with the Moving Subject
Suitable for Elements – 5.0, 4.0, 3.0, 2.0, 1.0 | Difficulty level – Intermediate Related techniques – 9.07 | Tools used – Clone Stamp, Selection tools | Menus used – Filter, Edit
One of the banes of the panoramic photographer’s life is the subject that moves during a shooting sequence. These may be people, cars or even clouds but no matter how good your nodal point selection or stitching is, these moving subjects cause very noticeable errors in panoramas. The stitched picture often features half a person, or object, as a result of Photomerge trying to match the edges of dissimilar pictures. These problems can be fixed in one of two ways – either remove or repair the problem area
(a) Remove – To remove the problem you can use the Clone Stamp tool to sample background parts of the scene and paint over stitching errors. The success of this type of work is largely based on how well you can select suitable areas to sample. Color, texture and tone need to be matched carefully if the changes are to be disguised in the final panorama.
Be careful though as repeated application of the Clone Stamp tool can cause noticeable patterns or smoothing in the final picture. These problems can be disguised by adding a little noise (Filter>Noise>Add Noise) to the image.
(b) Repair – In some instances it is easier to select, copy and paste the damaged subject from the original source image into the flattened panorama picture. This approach covers the half blended subject with one that is still complete. If you have used the Perspective option in Photomerge or have resized the panorama then you will need to adjust the pasted subject to fit the background. Use the Elements transformation tools such as Rotate, Perspective and Scale to help with this task.
Step 1 >> Using the Clone Stamp tool (or Healing Brush tool), sample the background around the moving subject and paint over the offending area.
Step 2 >> As repeated stamping can produce a noticeable smoothing of the treated area, disguise the effects by adding a little texture back to the picture with the Add Noise filter.
Step 1 >> Using one of the selection tools, outline the problem area in the original source image.
Step 2 >> Feather the selection by a couple of pixels. This will help blend the selected area when it is added to the panorama.
Step 3 >> Copy the selected area (Edit > Copy), click onto the panorama document and paste (Edit > Paste) the selection. Use the Move tool to move the copy into position.
Step 4 >> Use the Eraser tool set to a soft edge and low opacity to help blend the edges of the pasted selection into the background.
Adjusting the opacity of the pasted subject while you are transforming will help you match its details with those beneath. When the editing is complete, then the opacity is changed back to 100%.
Finishing touches can be applied to the edges of the pasted images to ensure precise blending with the background with the Eraser tool.
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Apply a slight feather (Select>Feather) to the selection before copying and pasting. This will help disguise the sharp crisp edge that is the tell-tale sign of so many repair jobs. A setting of 1 or 2 pixels at the most will be sufficient. |
Misalignment >> When capturing source images by hand, or using a standard tripod, slight changes in perspective and position result in Photomerge having difficulty in matching the edges of sequential pictures.
The misaligned picture parts need to be edited and rebuilt using a combination of the approaches outlined in technique 9.09.
9.10 Fixing Misaligned Picture Parts
Suitable for Elements – 5.0, 4.0, 3.0, 2.0, 1.0 | Difficulty level – Intermediate Related techniques – 9.09 | Tools used – Clone Stamp
Shooting your source sequence by hand may be your only option when you have forgotten your tripod or you are purposely travelling light, but the inaccuracies of this method can produce panoramas with serious problems. One such problem is ghosting or misalignment. It is a phenomenon that occurs when edge elements of consecutive source pictures don’t quite match. When Photomerge tries to merge the unmatched areas of one frame into another the mismatched sections are left as semi-transparent, ghosted or misaligned.
The affected areas can be repaired using the clone stamp techniques detailed in technique 6.09 but by far the best solution, and certainly the most time, efficient one, is to ensure that the camera and lens nodal points are situated over the pivot of the tripod at the time of capture. A little extra time spent in setting up will save many minutes editing later.
Too much contrast >> When the contrast range of a scene exceeds the abilities of the camera’s sensors, some of the details at the highlight and shadow end of the spectrum are lost. These details are converted to pure white and black. Panoramic pictures that encompass a wide angle of view often suffer from this problem. (a)Range of brightness and detail in the scene. (b)Brightness range of the scene is reduced (clipped) as it is recorded by the sensor. (c)Reduced range of detail and brightness as it is stored in the digital file.
9.11 Coping with Extremes of Brightness
Suitable for Elements – 5.0, 4.0, 3.0, 2.0, 1.0 | Difficulty level – Intermediate | Resources – Web images 911-1, 911-2, 911-3 | Related techniques – 9.03 | Menus used – Layer
Both film and digital cameras have a limit to the range of brightness that they can capture before details in shadow and highlight areas are lost. For most shooting scenarios the abilities of the average sensor or film is up to the job but in certain extreme circumstances, such as when a panorama encompasses both a view of a sunlit outdoor scene as well as a dimly lit interior, the range of tones is beyond the abilities of these devices.
Rather than accept blown highlights or clogged shadows, the clever panorama photographer can combine several exposures of the same scene to extend the range of brightnesses depicted in the image. The process involves shooting three (or two for less brightness difference) images of the one scene using different exposures. Each exposure is designed to capture either highlight, mid tone or shadow details. The difference in exposure should be great enough to encompass the contrast in the scene. These exposures can be captured automatically using the exposure bracketing technology that can now be found in most medium to high range digital cameras.
Combining the three images: With the three separate image documents open in Elements, hold down the Shift key and drag the background layers of two of the images onto the canvas of the third. Holding down the Shift key will make sure that the new layers are kept in register with the existing background. With the Layers palette open, rename and rearrange the layers so that they are ordered top to bottom – underexposed, normal and overexposed.
Changing the overexposed layer To blend the overexposed image, firstly turn off the topmost layer (underexposed), then change the normal layer’s blending mode to Screen. Now select the overexposed layer and choose the Levels function from the Enhance> Adjust Brightness/Contrast menu. Drag the white Output slider towards the middle of the control, watching the results preview on screen. When the shadow details are visible and you are satisfied with the effect, click OK.
Changing the underexposed layer To blend the underexposed image, select its layer and change the blend mode to Multiply. With the layer still selected choose the Levels function and drag the shadow Output slider towards the center of the dialog. When the highlight and shadow details are visible and you are satisfied with the effect click OK. Save a layered version of this image as the original and a flattened (no layers) copy which can be imported into Photomerge as a source image for your stitch.
Capturing all the detail >> With your camera fixed to a tripod, shoot three separate images adjusting the exposure settings to: (a)two stops over indicated exposure,(b)indicated exposure and (c)two stops under the settings indicated by your camera.
Step 1 >> Open the images with different exposures. Tile the documents so that all pictures can be seen (Window > Images > Tile).
Step 2 >> Drag two of the pictures onto the third with the Move tool whilst holding down the Shift key.
Step 3 >> Arrange the layers so that from top to bottom they are positioned underexposed, normal and overexposed. Name the layers.
Step 4 >> Hide the top layer by clicking the Eye icon. Change the normal layer’s mode to Screen. With the overexposed layer selected, choose the Levels function. Drag the white point Output slider towards the center of the dialog.
Step 5 >> Change the mode of the underexposed layer to Multiply. Select the Levels feature and move the black point Output slider towards the center of the dialog.
Step 6 >> To fine-tune the process, apply a Levels adjustment layer (Layer > New Adjustment Layer > Levels) to the stack, being sure not to clip newly created highlight and shadows detail.
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This technique can be applied non-destructively to the layered image by using Levels adjustment layers to change the tonal values of the under- and overexposed layers. To ensure that the levels adjustment is only applied to a single layer start by inserting the adjustment layer above the layer to be changed. Next make the tonal alterations and then group the adjustment layer with the changed layer using the Editor: Layer > Group with Previous command. |
9.12 Creating Artificially Increased DOF
Suitable for Elements – 5.0, 4.0, 3.0, 2.0, 1.0 | Difficulty level – Intermediate Related techniques – 9.06 | Tools used – Selection tools, Eraser | Menus used – Edit
In some environments it may not be possible to gain enough depth of field to extend the sharpness from the foreground details into the background of the picture. In these circumstances you can still simulate this large depth of field by shooting two different sets of source images – one with focus set for the foreground objects and a second set for the background details. Later, at the desktop, the sharp detail from the foreground can be cut out and pasted over the background pictures. As we have seen with other cut and paste techniques, a little feather applied to the selection before cutting helps to ensure a convincing result at the pasting stage.
Step 1 >> Open the two source files. Carefully select the foreground detail using your favorite selection tool. Feather the selection by 1 pixel.
Step 2 >> Copy and paste the selection onto the background, using the Move tool to position. Clean up with the Eraser tool if needed.
Artificially increasing depth of field >> Increase the amount of your panorama that appears sharp by cutting and pasting between two separately focused and shot sequences.(a)Sharp details. (b)Unsharp details.
9.13 Correcting Exposure Differences
Suitable for Elements – 5.0, 4.0, 3.0, 2.0, 1.0 | Difficulty level – Intermediate Related techniques – 9.03, 9.14 | Tools used – Eyedropper | Menus used – Image, Window
Changes in density from one source image to the next can occur for a variety of reasons – the sun went behind a cloud during your capture sequence or the camera was left on auto exposure and changed settings to suit the ‘through the lens’ reading. The images that result vary in density. When these images are blended the change in tone is most noticeable at the stitch point in large areas of similar color and detail such as sky or road surface.
Auto Fixes – Photomerge contains an ‘Advanced Blending’ feature that tries to account for slight changes in overall density from one frame to the next by extending the graduation between one source image and the next. This ‘auto’ technique will disguise small variations in exposure and generally produce a balanced panorama, but for situations with large density discrepancies the source images may need to be edited individually.
Manual Fixes – The simple approach to balancing the density of your source images is to open two or more of the pictures and visually adjust contrast and brightness using tools like the Levels feature. For a more precise approach it would be useful to know the exact values of the same section of two overlapping images. The Info palette in Elements displays the RGB values of a specific area in a picture. When used in conjunction with the Levels feature it is also possible to display the values before and after density changes. Knowing the RGB values of the first image, you can alter the values in the second to match, thus ensuring a seamless stitch.
Advanced Blending >> The Advanced Blending option in Photomerge can help to disguise slight differences in contrast, brightness and color.
Info palette >> With the aid of the Info palette you can easily determine differences in color, brightness and contrast between sequential source images.
- You have your camera set to manual exposure, and
- You are capturing all the source images under the same lighting conditions.
Density correction >> Fixing brightness or contrast differences before stitching will produce a far better result than expecting Photomerge to hide these problems.
(a)Before. (b)After.
Step 1 >> Open a picture with good brightness and contrast as well as the picture that needs adjusting. At the same time display the Info palette (Window > Info)..
Step 2 >> Click onto several matching points on both pictures taking note of the red (R), green (G), blue (B) and grayscale (K) settings for each.
Step 3 >> Make contrast and brightness adjustments to the problem image checking the changed readings in the Info palette as you go until both pictures display similar values..
9.14 Adjusting for Changes in Color Balance
Suitable for Elements – 5.0, 4.0, 3.0, 2.0, 1.0 | Difficulty level – Intermediate Related techniques – 9.13 | Tools used – Eyedropper tool | Menus used – Image, Window
Slight changes in the color balance of sequentially shot images can result from using the Auto White Balance feature to rid images of casts resulting from mixed light sources. As the color of each frame is assessed and corrected independently, changing subject matter can cause such color shifts. More uniform results are obtained if the white balance is set based on the primary light source in the scene and then kept constant for the rest of the shooting sequence.
Ensuring consistency >> Using the Info palette in conjunction with both the Levels and Color Variations features will enable you to balance color, brightness and contrast of sequential images.
(a) Info palette.
(b) Levels feature.
(b) Color Variations..
For slight discrepancies in color, tools such as the Auto Color Correction (Enhance>Auto Color Correction) feature will be able to automatically even out some of the changes, but for big changes in color a frame-byframe correction technique similar to the one outlined for exposure differences can be used. This time instead of using Levels to make your adjustments you can employ a color control feature such as Color Variations (Enhance>Color Variations), which can be used in conjunction with the Info palette to match different color values in sequential images.
Suitable for Elements – 5.0, 4.0, 3.0, 2.0, 1.0 Difficulty level – Basic | Related techniques – 9.16
For most of the time you will probably use Photomerge to make horizontal panoramas of wide vistas, but occasionally you may come across a situation where you can make use of the stitching technology to create vertical panoramas rather than horizontal ones. When capturing the vertical source images be sure to follow the same guidelines used for standard panoramas, i.e. check exposure, focus, white balance, focal length and shooting position
Vertical stitching >> Don’t restrict yourself to only stitching horizontal pictures. Why not also use Photomerge to stitch those very tall shots that you just can’t capture in a single photograph?
Step 1 >> Add your pictures to Photomerge as you would for a horizontal composition.
Step 2 >> Photomerge may display an error message as it tries to automatically arrange the pictures. Click OK.
Step 3 >> Manually drag the unplaced pictures into position. Turn on Perspective and Advanced Blending before clicking OK to finish the stitch.
Suitable for Elements – 5.0, 4.0, 3.0, 2.0, 1.0 | Difficulty level – Basic | Related techniques – 9.15
Another not so familiar use of the Photomerge technology is the production of high-resolution picture mosaics. In this application, the photographer captures a series of overlapping images, both vertically and horizontally, of the same scene. These images are then stitched together to form a photograph that is both wider and taller and contains more pixels than your camera would normally be capable of.
This approach is particularly suitable for those scenes where you just don’t have a lens wide enough to encompass the whole vista, or situations where detail is critical. The higher resolution of the final stitched result also provides the extra digital information necessary to print big pictures (A3, A3+ or even A2) with little or no loss of quality or detail.
Unlike when you are capturing the source pictures for panorama production, high-resolution stitches require pictures that overlap on all sides that are to be stitched. This means that at the time of shooting you need to pay particular attention to edges of the frame and ensure a 20 to 40% consistent overlap.
Pro’s Tip: If your camera contains a grid feature that can be displayed in the viewfinder, position the grid line closest to the edge of the frame on a subject that will be present in the overlap. Next turn the camera and make sure that the same subject is present in the frame on the grid line at the opposite side of the viewfinder
Mosaic stitches >> Create very high-resolution wide angle pictures that contain stunning detail and quality by capturing a series of overlapping pictures and stitching them with the Photomerge feature. (a)Mosaic source images that overlap on all stitching sides. (b)Turn on both the Advanced Blending and Perspective options in Photomerge. (c)Use the Cropping tool to trim away the ragged edges that are the result of the perspective deformation. (d)The final mosaic picture is higher resolution and covers more of the scene than would have been possible with a single camera shot.
Suitable for Elements – 5.0, 4.0, 3.0, 2.0, 1.0 | Difficulty level – Intermediate Related techniques – 10.01 | Menus used – Edit
Given the format of most wide vista photographs, printing on standard inkjet paper will result in much of the printing surface being left unused. Printer companies like Epson now produce pre-cut panoramic paper in a photographic finish. These sheets are convenient to use and their proportions are stored as one of the default paper settings on all the latest model printers.
Another approach is to use the roll paper format that is now available as an option on several different models. This option provides the ability to print both long, thin and standard picture formats on the same paper, reducing the need for multiple paper types. Using these special roll holders the printer can output different image formats back to back and edge to edge, providing cutting guidelines between pictures if needed.
For those of you with just the occasional need to print panoramas, another approach is to cut standard printing papers lengthways. This action produces very usable wide thin stock that is half the usable dimensions of the standard sheet. See the table below for the different paper types and the panorama print sizes that can be output on each.
With the paper organized it is now necessary to set up the printer for the new sizes. If you are using the pre-cut sheet or roll paper, then these options should be available in the drop-down paper menu of the latest printer driver for your machine. If the options are not present, or you are using panorama paper that you have cut yourself, then you will need to set up a custom paper size to suit your needs. On Epson machines you can do this by opening the printer driver, selecting the Paper tab and choosing the User Defined option. The dialog that is displayed will allow you to create, label and save your own paper size. These newly created paper size options will then be available for you to choose when you next open the Elements print dialog. More printing techniques can be found in Chapter 10 of the book, including instructions for making a panorama-friendly Picture Package.
| Basic Paper Type | Possible Panorama Print Size |
| A4 | 105 × 287 mm (1/2 full sheet) |
| A3 | 148 × 420 mm (1/2 full sheet) |
| A2 | 210 × 594 mm (1/2 full sheet) |
| A4 Roll | 210 mm × 10 m |
| 100 mm wide roll | 100 mm × 8 m |
| panoramic Paper | 210 × 594 mm (pre-cut sheet) |
Step 1 >> Select the Paper tab from the Epson printer driver and choose User Defined from the drop-down Paper Size menu. Input the paper size in the width and height boxes and then save the settings. Click OK..
Step 2 >> Once saved the new paper sizes can be found as extra options under the Paper Size menu.
Step 3 >> When it comes time to print a panoramic picture you can now select one of your pre-defined paper sizes and Elements will preview the photograph positioned against the background of the new paper format.
Panoramic print options >> Because of the wide thin nature of most panoramic photographs, printer companies like Epson have developed special settings for their hardware as well as a range of paper sizes to accommodate the unusual format. (a) Roll paper can be customized to suit both standard print formats as well as wide panoramic prints. (b) pecial pre-cut papers in ‘photo print’ finishes are also available. Panoramas can be printed on standard paper sizes, but much of the sheet is left blank.
Suitable for Elements – 5.0, 4.0, 3.0, 2.0, 1.0 | Difficulty level – Intermediate | Resources – Web links
Many wide vista photographers choose to present their work in an interactive spinning format rather than as a print. This way of looking at images is often called Virtual Reality (VR) and is used extensively on the internet to give viewers the feeling that they are actually standing in the environment they are seeing on screen. Holiday destinations and real estate previews come to life via this technology. When the VR panorama opens you can navigate around the scene looking left and right with nothing more than simple mouse movements.
Although the ability to output your flat panoramic pictures in a VR format is not an integrated function of the Elements Photomerge feature there are several options for those who want to get their wide vista pictures spinning.
Moving panoramas >> Photomerge users can take their panorama pictures beyond the static print by converting their stitched images to spinning vistas that can be navigated on screen and distributed via the web. For a complete 360° spin overlapping images need to be captured for the whole scene
Converting Flat Pictures to Spinning Movies
The process of getting your flat Photomerge panoramas to spin on screen involves two essential steps:
- Converting the pano photograph to a format that is suitable to be displayed, and
- Linking the converted file to a viewer or presentation utility which actually controls the on-screen display.
The standard QuickTime web plug-in, that can be freely downloaded from Apple and installed, is the most well known of all VR viewers. Along with being able to show movies, play sound and display a variety of still picture files the plug-in can also show panoramic movies that are saved in the QuickTime movie format. The viewer includes buttons to zoom in (‘+’) and zoom out (‘−’) of the panorama and the viewer navigates the scene by click-dragging the cursor side to side or up and down in the display window.
Apple QuickTime Viewer >> The QuickTime plug-in is the most well known of all the VR viewers.
There are many commercial, shareware and even freeware utilities that will help you convert your flat Photomerge Panorama files to the QuickTime VR movie format (QTVR). Most of the commercial programs contain their own stitching utilities (like Photomerge) and the Conversion to VR movies feature is just one of the many output options offered. As Photomerge users don’t need the stitching component of these programs the QuickTime utilities included here and detailed below only handle the conversion process. Once converted to the QTVR format the files can be viewed using the QuickTime plug-in
There is also a range of non-QuickTime viewers and conversion utilities. Most of these use a small Javascript-based program to provide similar display features to those found with QTVR. Again, most utilities used for creating these non-QuickTime movies are included with stitching features in a fuller program, but the options detailed below use stand-alone software to create spinable movies from basic JPEG panorama picture files.
Free convert to QuickTime VR utilities:
Go to developer.apple.com/samplecode/VRMakePano/VRMakePano.html and download the VRMakePano utility.
OPTION 1: Converting Photomerge Output to the QuickTime Movie Format
Elements users can convert their Photomerge output to Apple’s QuickTime VR movie format using a free utility available from the Apple website. Both Windows and Macintosh versions of the software are available. Simply save the stitched image as a Macintosh PICT file, rotate it to the left (so that it is tall and thin) and then convert the picture using the Make Panorama utility. The resultant file can be viewed (and navigated) with any QuickTime player and has the added bonus of being able to be uploaded to the web and viewed on-line.
Step 1 >> Rotate the completed Photomerge file to the Left (Image > Rotate > 90° Left before saving as a PICT file (File > Save As).
Step 2 >> Start the VRMakePano utility and open the PICT file via the Test > Make Movie menu. Follow the onscreen prompts and specify image, tile and movie files in the dialogs provided.
Step 3 >> In a new dialog you will be prompted to export the results to a movie file. Here you can adjust the quality and size of the final panorama using the options on this screen.
Windows users can make similar spinning panoramas to those destined for displaying in a QuickTime viewer using a small economical utility called Pano2Exe (http://www.change7.com/pano2exe/). The program converts JPEG output from Photomerge to a self-contained EXE file, which is a single easily distributable file that contains the image itself as well as a built-in viewer.
Step 1 >> Save completed Photomerge file as a JPEG file (File>Save As or File> Save for Web).
Step 2 >> Open picture into Pano2Exe program (File > Open Panoramic Image) and set width and height of navigation window.
Step 3 >> Save the spinning panorama as an executable file (.EXE) ready for distribution.
Pano2Exe >> The Pano2Exe utility provides a convenient and economical way to convert your Photomerge vistas to distributable navigable panoramas. See www.change7.com for details.
OPTION 3: Making web pages with a Java Applet-Based Viewer
For those readers with a good understanding of how to create web pages you can also add your Photomerge panoramas to your website with the aid of a small piece of viewer code. In most cases this code is supplied in the form of a Java Applet. Civic-minded developers like Karl Maloszek at www.panorado.com supply their own applet for free when used on private websites.
The web panorama page is built of three components:
- The HTML page,
- The panorama image file (saved as a JPEG), and
- The viewer applet.
These three files must be present in order for the page to display properly. To create a panorama page you will need to download the Panorado applet and save the Java archive (Panorado.jar) to your destination folder. Next create a blank web page and insert the HTML code, that controls the viewer and links your panorama photo to the viewer, into the code of the page. To make this process a little easier, for example HTML code can be cut and pasted from the Panorado website directly into your page.
Java applet >> www.Panorado.com provides Java Applet viewer that can be used free of charge for non-commercial websites.
The viewer can be positioned in a scalable pop-up window which also contains HTML-based control buttons or in the middle of a document page (normally in a smaller rectangle or frame).
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Creating web pages using a Java-based viewer is not as automated as the other two approaches detailed previously. The process requires that the user understands the basics of HTML coding and how to correctly set parameters in that code. |
WWW.PANORADO.COM >> Karl Maloszek at Panorado produces a non-QuickTime viewer that can be used to create interactive panorama web pages. Along with his applet and viewer software his site also contains a variety of example panoramas that display how this technology works. Images courtesy of www.panorado.com © 2005.
If the ‘proof of the pudding is in the eating’ then the success of all your careful shooting, stitching and editing work is in the viewing (of the final panorama). Logical planning and execution is the key to high quality wide vista photographs.
In this chapter I have introduced a range of techniques that will help you make great panoramas, but remembering the techniques and order that they should be used can be difficult. Use the steps in the workflow table (aside) to help you sequence your setting up, shooting, stitching, editing and producing activities.
