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Posted on 10/04/06 8:04:38 PM
tank172
ThreeDee Thriller
Posts: 692

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Photomerge problems
I've merged 4 photos together and came up with this catastrophe! How would I correct this lighting problem? I've tried color match, curves, levels...etc.

Posted on 10/04/06 8:05:16 PM
tank172
ThreeDee Thriller
Posts: 692

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Re: Photomerge problems
oh, maybe the photo would help!




Posted on 10/04/06 8:06:38 PM
tank172
ThreeDee Thriller
Posts: 692

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Re: Photomerge problems
I haven't started correcting the lens distortion and all that. Just fighting with the lighting from the separate photos.

Posted on 10/04/06 8:52:14 PM
chris
Photo Parodist
Posts: 138

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Re: Photomerge problems
You could try the replace colour tool to get an even colour through out the 4 images or maybe blending the layers amy help. Becky is the expert on blending me thinks and maybe she would be able to shed some light (no pun). If you could post all 4 images it would make quite an interesting friday challenge.

Posted on 10/04/06 10:01:07 PM
rufus
Destructive Demon
Posts: 243

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Re: Photomerge problems
Try Autostitch as recommended by Pierre.

http://www.howtocheatinphotoshop.com/cgi-bin/simpleforum_pro.cgi?fid=07&topic_id=1143676338

Posted on 10/04/06 10:35:01 PM
tank172
ThreeDee Thriller
Posts: 692

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Re: Photomerge problems
Already tried Autostitch and It came up with a mushroom cloud affect. Autostitch is a great program; however, it definately threw a fit for some reason when I wanted it to process the photos.

Posted on 10/04/06 10:35:33 PM
tank172
ThreeDee Thriller
Posts: 692

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Re: Photomerge problems


Posted on 10/04/06 10:36:07 PM
tank172
ThreeDee Thriller
Posts: 692

Reply


Re: Photomerge problems


Posted on 10/04/06 10:37:09 PM
tank172
ThreeDee Thriller
Posts: 692

Reply


Re: Photomerge problems


Posted on 10/04/06 10:37:37 PM
tank172
ThreeDee Thriller
Posts: 692

Reply


Re: Photomerge problems


Posted on 10/04/06 10:39:17 PM
tank172
ThreeDee Thriller
Posts: 692

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Re: Photomerge problems
Sorry Steve, I really hope this doesn't hurt your bandwidth too badly. You really should have a link for donations... ..

Posted on 10/04/06 10:41:57 PM
tank172
ThreeDee Thriller
Posts: 692

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Re: Photomerge problems
Unfortunately, I don't have a tripod... It would definately help Photoshop or Autostitch with the perspective blending a bit.

Posted on 11/04/06 02:40:15 AM
Bob
Expert Expressionist
Posts: 130

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Re: Photomerge problems
Chris,

You need to try for more overlap on the images. When I first tried to use Autostitch, it omitted 5557 because it did not have enough match points. I was able to get Autostitch to join just 5557 and 5558 by adjusting the ransac parameters and was then able to stitch that joined image with the remaining images. But, that's not the best way to go and quality probably suffered because you can't pin down 5557's orientation precisely.

The "mushroom" effect was caused by not unchecking the Auto Straighten option. Autostitch tries to find the horizon and straighten the image. You don't have a clearly defined horizon.

Here's the stitched image. It would have been much better if the overlapped regions were wider. A tripod would help, but it's really the size of the overlap region and the number of unique matchpoints that determine how well Autostitch can correct for the geometric relationships. Don't be afraid to take more shots and overlap more.

Does your camera have a panorama assist function?







Posted on 11/04/06 09:19:36 AM
Steve Caplin
Administrator
Posts: 6938

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Re: Photomerge problems
That's a great merge, Bob.

I think a lot of the trouble in the original photos comes from having the camera set to auto-everything. For multiple shots like this - some taken directly towards windows, some at darker ceilings - you need to set a single exposure and speed and then stick to that.

Posted on 11/04/06 7:04:03 PM
rufus
Destructive Demon
Posts: 243

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Re: Photomerge problems
At 02:40:15 AM 11/04/06, Bob wrote:
I was able to get Autostitch to join just 5557 and 5558 by adjusting the ransac parameters and was then able to stitch that joined image with the remaining images.


Bob. I tried adjusting the ransac parameters but I still couldn't get the images to stitch, what settings did you use?

rufus

Posted on 11/04/06 7:19:44 PM
tank172
ThreeDee Thriller
Posts: 692

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Re: Photomerge problems
Wow Bob, wonderful attempt! I seem to be having the same problems as Rufus, though. 5557 doesn't seem to agree with Autostitch. After reading the Readme file that came along with the program, I was able to adjust the ransac parameters and Sift modes in the right direction...but still could not get 5557 to merge. Autostitch did, however, blend the lighting on the 3 other photos seamlessly!

Chris

Posted on 11/04/06 8:00:21 PM
Bob
Expert Expressionist
Posts: 130

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Re: Photomerge problems
I made a mistake and said 5557 and 5558 when I should have said 5556 and 5557. Sorry about that!

I left the Sift parameters alone and only adjusted the ransac parameters. I didn't write them down but believe I used alpha 5 and beta 0.05. I arrived at these by trial and error. Auto straighten was unchecked. Here's what I got for the merge of the two images.



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