I've been spending a lot of time recently making panoramas using PS's photomerge feature and I decided to write up a little tutorial/advice post with some examples for my photography friends. Plus, I like to write and I haven't done very much of it recently so it's nice to find an excuse.
Anyway, before I send around I figured I'd try and get some feedback/criticism here, from some experienced eyes, first.
If you have a minute I would really appreciate some feedback -- does my experience match your experience with photomerge? Any big tips or tricks that you think I missed?
When you capture, use the vertical camera orientation. Also, consider vertical panos using the horizontal orientation. Tiled panos are above my pay grade.
(Is this in there?) Be sure to do lens correction.
In ACR or LR, go through the shots looking at the histogram. You can decide which photo to correct and then sync.
When all else fails, do not be afraid to edit the masks.
An advanced move, you can use puppet warp in CS5 to correct distortion. I think Russell Brown has a tutorial.
Also I merge the layers and select the image, inverse the selection, expand the selection, and then do content aware fill. (also Russell Brown)
Sorry for being terse, but hand held panos are fun. You can walk away from them for a while and come back and improve.
1. You mention using Manual (M) exposure mode. You might add that Auto ISO should be off (particularly relevant for Nikon users). I often use M mode with auto ISO and that would be just as problematic as aperture or shutter priority modes.
2. You might emphasize the need to pick the right single exposure setting that will need to work best for the scene as a whole - no point getting the shadows right at one end if it burns out the details at the other end. In other words, pay attention to the brightness level across the whole scene rather than just in one photo.
3. Given the pinched shape of the perspective corrected panorama it is important to allow plenty of height above and below the area of most interest in the centre images so that you can retain more of the interesting bits in the end images. The content fill aware that Steve mentioned would help too. I must read up on that.
4. Check this, but I think that rotating the central image slightly will skew the entire panorama such that the left and right heights will be very different. So check levels carefully - which may mean *not* aligning with the horizon if the horizon is not flat.
5. As Steve pointed out, apply lens corrections before stitching. Also level and perhaps crop each image individually as required. Also apply noise reduction and capture sharpening as that could improve image alignment. These corrections can all be done with raw image data prior to being dumbed down to lower bit depth such as in a jpg file.
6. In the sample panoramas you posted the left and right edges of the end result were not always parallel. You can apply perspective corrections (transformations) to fix this before you do any final cropping. It may or may not improve the end result. See also point 11 below. The more level the input images are when captured the more level the panorama is likely to be.
7. I have found that panoramas with a maximum length:height ratio of 3:1 work pretty well when viewed as a standard flat print on a flat wall. Much longer and it looks like it ought to be wrapped around you rather than viewed in front of you - something that cannot be done unless the print is huge. Put another way, 360 degree panoramas often don't work as well (i.e. as realistic) as say 90 degree panoramas - but they do let you pick which 90-degree segment you want to print, or even make several different prints.
8. You might mention that the cheaper point and shoot cameras often have a pano mode that displays some of the previous image on the LCD screen to help you align the next image more precisely in-camera with the right amount of overlap. You don't get this on the top shelf DSLRs but it works well.
9. You might mention focus. Unless you have adequate DOF you need to pick a suitable focus distance and use it for all of the photos. Panoramas look odd when one image in the set is focused differently from the rest because the user had AF on instead of MF. As with exposure, this has to be done with the whole scene in mind before you start.
10. I expect that most people who make panoramas want to print them but on a small printer they can lose much of their impact, perhaps being only a very few inches tall. Printers that can handle roll paper may be more appropriate.
11. You might mention the advantages of using a shift lens (or even shift and tilt) to make all of the component images align better. This is especially useful if you would otherwise have to point the camera up or down while you pan left or right. This sort of thing can also be done by processing each image for perspective correction separately before stitching. Alternatively, keep the camera pointing horizontally and just use whatever part of the scene
fits the images.
12. Practice will help. It is advisable to learn the techniques before going on a special holiday and ruining what might otherwise have been a good panorama sequence that cannot easily or cheaply be re-shot when the holiday is over.
Overall I thought your tutorial was well presented. It's not too complex but panos can be complex. I think it fair that the readers be told this so that they can avoid more of the hidden pitfalls.
Thanks for the comments guys -- I've incorporated a couple of them (with credits) to the post now. Obviously, like Alan said, panos can be complex. I think it might be worth pursuing a post discussing some of the more advanced techniques... just see if I have time and energy to do it .
Before importing, be conservative in your exposure adjustments. I don't know why. I stitched a large pano with aggressive exposure AND fill AND recovery. There were several bad jaggies. I stitched using conservative settings and it was much better.
One other anomaly CS5 has memory issues. I use a 64 bit with lots of memory, but I still have to save and reboot. Yet another, I don't know why but it works. A 180 meg pano means CS5 uses 5 gb of memory. Ouch.
I made a mistake and used autoexposure so the layers had different exposures. CS5 did not merge well. I adjusted the exposure before merge, and it worked better. There are commands in PS that merge layers by content and then blend exposure.
It's a nice guide, wish I had something like that when I first started to shoot panoramas.
May I add something to make it even more comprehensive?
For shooting pano that has something on foreground, use hyperfocal distance, so that you get most of your objects in focus.
Few suggestions on pp:
1. I found that stitching from Bridge is much easier than directly from PS.
If possible, shoot in raw, then open all images in converter at once, select all, and make most adjustments (including contrast, color and lens correction) while still in raw. Sync them, and then, select "done". Go to "Tools" and with images still selected, do "Photomerge."
2. I do not mess with stitching menu, and always leave it in "Auto" - but I do select vignette and distortion correction. When PS is done stitching, merge all layers, pull vertical and horizontal guides and align them with horizon (and/or whatever other important geometrical features are present that need to be straight), and correct distortion by Transform -> Wrap.
3. If the pano looks overall good but missing few uniformly colored fragments, it's very easy to fix with "fill by content" feature.
alatoo60 wrote:
It's a nice guide, wish I had something like that when I first started to shoot panoramas.
May I add something to make it even more comprehensive?
For shooting pano that has something on foreground, use hyperfocal distance, so that you get most of your objects in focus.
Few suggestions on pp:
1. I found that stitching from Bridge is much easier than directly from PS.
If possible, shoot in raw, then open all images in converter at once, select all, and make most adjustments (including contrast, color and lens correction) while still in raw. Sync them, and then, select "done". Go to "Tools" and with images still selected, do "Photomerge."
2. I do not mess with stitching menu, and always leave it in "Auto" - but I do select vignette and distortion correction. When PS is done stitching, merge all layers, pull vertical and horizontal guides and align them with horizon (and/or whatever other important geometrical features are present that need to be straight), and correct distortion by Transform -> Wrap.
3. If the pano looks overall good but missing few uniformly colored fragments, it's very easy to fix with "fill by content" feature. ...Show more →
Very useful additions - thank you for sharing. I'll be trying your recommendations soon.
I stitched a multi-row HDR panorama that ended up with 170 megapixels. The panels were 12 MPx. There were two rows of 12 panels, three shots per panel for a total of 72 frames (144 clicks of the shutter with mirror lockup).
Stitching took four and a half hours on a six core processor. Most of the time Hugin was using the equivalent of two cores but for short periods it used all six cores at once. Base system usage is about 2 GB and Hugin took an extra 3 GB above that (for a total of 5 GB in use).
Good write up and suggestions by all. I found the white text on the black background a little tough on the eyes after a bit. Any chance of slightly lightening the background? Good stuff though. Also, perhaps point out that it's best to try to pivot the lens over it's optical center rather than swinging the camera around. That's more critical when there are objects close up but it's good practice. Nice job.
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