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Gunna
06-09-2010, 8:03pm
I have shot a series of RAW shots to do a panorama.
Do I adjust the individual shots & then stitch,
or stitch 1st, then make adjustments to the composite?

Remorhaz
07-09-2010, 2:10pm
I used to always stitch first and then adjust the result - however the last time I actually adjusted the RAW's first before stitching (however I ensured I applied the same adjustments (in Lightroom) to all the source images). The thing to be careful with here is fixing one image (e.g. exposure) and not the others in the same way because you end up with it being stitched OK but there's an obvious transition between images (e.g. in the sky).

I'm presuming you took all the images with the same exposure settings locked (e.g. same aperture/shutter speed/ISO, etc).

dieselpower
07-09-2010, 2:10pm
It depends - how's the white balance? If the white balance on each frame is the same then I go straight for a stitch and adjust the composite. If the WB is out then I'll set it first and then stitch. I use auto WB on my camera and find I nearly always need to adjust the WB before stitching.

I once did some tone adjustments before stitching but only because I needed to correct slightly a few parts that would have been more difficult to achieve on the composite.

Good luck - show us what you turn out with!

Gunna
11-09-2010, 12:57pm
Thanks for the advice guys.
I've got a bit of work to do!

vk2gwk
13-09-2010, 7:45pm
As adjusting an image in RAW is far more effective than later on when it has been converted I prefer to do the adjustments in RAW before stitching. However.... you got to make sure that any "over all" adjustment you make are made in all files. so when you adjust the exposure, white balance, contrast and so on the adjustments should be the same for all files. There are exceptions to this rule. I have applied a "virtual" GND filter in ARC from "left to right" to brighten up one side of the panorama and I have done spot exposure corrections with the "correction brush" in one file. You have to keep in mind that in stitching you should not be able to notice the seams - which means that all contributing files should where they meet or overlap be about the same exposure level , contrast, brightness and colour temperature. Within these margins you can correct anything you like.

ameerat42
13-09-2010, 8:01pm
Gunna, dieselpower ran off with my words. For panos, keep things as constant as you can, preferably in camera, but by judicious PP if no. Am.

mynxt
14-09-2010, 11:47am
I've notice when stitching my first pano in CS5, when the image is small enough to see it completely on the screen, you can see the stitch marks. When you zoom in, the stitch marks disappear. Is this usual?

ameerat42
14-09-2010, 12:10pm
Yes for many programs. The preview is a quick result based on an early operation of the program AFAIK. Am.

achee
23-09-2010, 12:52pm
I've only used 'photostitch' that comes with my Canon, and that can only process JPEGS (actually, I haven't tried TIFF or BMP). Can the better programs work with raw files?

I tried a pano of my kitchen, and when trying to stitch the photos together I noticed that they are really distorted - lens distortion I suppose! (Tamron 17-50 @17mm) Putting these into photostitch doesn't come up with great results. Should I try fixing the distortion before putting submitting the photos to Photostitch? Or... should I just get another program?

By the way, I used a tripod and tried to rotate around the lens entry point, used fully manual settings etc.

On that point, any suggestions on programs? If I can get a free one to do a good job, then free, but otherwise not-too-expensive!

Oh, and one more question: How do you make HDR images into HDR pano's? I've recently started playing with a program called picturenaut that seems to do (IMHO) a great job of combining bracketed photos. Would I run the pictures through that first, then through the stitching program? Or do some stitching programs handle HDR as well?

ameerat42
23-09-2010, 4:23pm
achee. What version of Photostitch? V3.1 stitches tiff, bmp, psd, and a couple of others.
About the distortion: how much overlap did you have, and for really wide lenses P-stitch sometimes falls down.
A free program? Hugin. It's not as easy to operate as P-stitch, but it'll take a lot of crap in images. The origina;l images are copied and reduced to 1600 px first, and then these are stitched.
Do you have a late-ish Adobe Photoshop. That'll stitch.
Another free one is Autopano. I have found it to be good as long as there are no transients in the original pics.

All have their limitations. To get them off the web just search on those names.
Am.

achee
23-09-2010, 5:35pm
Thanks! Yeah, I'm using Photostitch 3.1. I only tried Canon's CR2 files and JPG. Good to know it does tiff's and bmp's etc.

I think lack of enough overlap may be one of my problems. I'll try again with more!

I don't have photoshop yet, although I'm getting the idea that anyone serious about doing PP needs it... How do you think PS, Photostitch, Hugin and Autopan compare?

ameerat42
23-09-2010, 6:53pm
Firstly, I haven't bothered to use Photoshop to stitch. Someone else may be able to tell you about that.
I'll try to list the downfalls of each product, then the good points, starting with the easiest.
Autopano: doesn't treat transients (people walking, movements in scene) very well. Pstitch and Hugin do it much better. But it will stitch almost anything.
Hugin: hard to pick a fault, but makes less than full size panos. This may not be such a problem since panos can be massive in size. It is not as easy as P-stitch and Autopano to use, but once you're used to it you'll find it powerful.
P-stitch: sometimes falters with blending tones and how it treats image distortions. I can say that I have more problems with seams in P-stitch than in the other two programs. It is easy to use. Does most things reasonably well.

I find that if one program doesn't do a good job I'll try the others. Mostly, thought, I rely on Hugin, but that's because it's updated a couple of times a year, unlike P-stitch. For no particular reason, I use Autopano least of all.

And lastly: don't expect great results straight away or even most of the time.

I've still got a few series of images that simply will not merge.
Am.

PS added as an edit: the amount of overlap is hard to judge. I try for about 1/4 to max 1/3. You should avoid getting bits of the same scene in every alternative image. That is, image 3 should not contain any parts of image 1, ...4 none of ...2, etc.

achee
24-09-2010, 7:20am
Sounds good, I'm downloading Hugin now! :D