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Old Jan 26, 2006, 11:08 AM   #1
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I took four pictures in a sunny day in order to make a parorama.

But the brightness between the four pictures are very different .

The stitching result can be seen here:

http://www.tianyou.net.cn/vr/res2.jpg

How can I avoid this?

Thanks
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Old Jan 26, 2006, 2:56 PM   #2
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All your answers are here:

Need Help on Stitching

Tom, on Point Pelee, Canada
http://tomoverton.myphotoalbum.com

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Old Jan 26, 2006, 3:05 PM   #3
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An evenly exposed panorama is difficult to achieve, especially if lighting conditions are different from one part of the scene to another,which isalmost always. Try to shoot your panos at right angles to the sun or away from it rather than at the sun or close to it, and try to avoid areas of deep contrast. Even lightingis the key, so look for scenes with the least amount of lighting variation.

Some cameras have Panorama modes that are great for stitching pictures together, but not so hot for producing evenly exposed panos because they usually lock the exposure settings with the first shot, which almost never has exactly the same lighting as subsequent ones.

I let my camera meter each shot individually, I thenpost-process the exposure in each shot to get them as even as possible. ThenIstitch them together.

Using a good quality tripod with bubble-levels is a must, although it is possible to get good hand-held panos.



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Old Jan 26, 2006, 5:37 PM   #4
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This is a 5-shot panorama I took yesterday on Cosens Bay Rd in Kalamalka Lake Provincial Park, facing directly away from the sun about 15 minutes before sunset. It took a lot of post-processing to get the exposures asevenas possible, and the ground matches up quite well, but you can still see the sky is uneven.
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Old Jan 26, 2006, 6:28 PM   #5
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My experience has been different from toshi43's. I do better guessing at my average light and pre-metering on that with the panorama then shot with the same exposure and WB. Then I can use contrast masking, shadow/highlight or a combination of them to even out the entire shot after stitching if the light is different.

Something that was pointed out on another thread is that if you are using an aux telephoto lens you will get differences at the stitch points because the light tends to drop off at the edge. I don't know of anything that can be done about that.

Did you try stitching with Autostitch? It seems to do a better job than average of evening out the lighting. The free version is still available but it expires.

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Old Jan 27, 2006, 7:56 AM   #6
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With my dial-up connection, I gave up trying to look at your pano.

I agree with slipe - it is easier to lock the exposure and white balance instead of adjusting later.Often can befixed later, but much more difficult.


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Old Jan 27, 2006, 11:50 AM   #7
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BillDrew wrote:
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With my dial-up connection, I gave up trying to look at your pano.

I agree with slipe - it is easier to lock the exposure and white balance instead of adjusting later.Often can befixed later, but much more difficult.

My previous digicam, a Canon A75, had a Panorama Mode that locked all exposure settings with the first shot. This worked OK for a 2 or 3 shot pano, but for wide panos of 5 or more shots, you could always see very obvious exposure differences between the first and last shots, because the quality of the light changes relative to your angle to the sun.

I've done quite a few lake panos, and the amount of light reflected from the water changes depending on what angle you're observing it from. When you look at the blue sky, it's never even from one horizon to another, it always changes in intensity and depth,subject to your viewing angle and atmospheric variables. Locking exposure for one set of lighting conditions will produce different results when those conditions change, even just a little.

Take a look at this pano taken with the A75,which is a typical example. You can easily see that with a single exposure setting the color of the sky and water havenoticeablydifferent intensity as you look from one side of the picture to the other, with obvious banding.

Letting the camera meter each shot individually will still produce shot-to-shot differences but they won't be as drastic, at least in my experience. Using post-processing to even things out later seems to work best for me.
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Old Jan 27, 2006, 3:30 PM   #8
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from a previous post

this is a pic to show how far out pics can be in difficult lighting



end result after a long time editing in photoshop.......yes i use photoshop to make my panos as i get more control



so as u see nothing is not doable LOL...with time and effort



but as a rule get light settings of one pic and turn to manual set it to same settings and take more shots.

i generaly take 3 or 4 lots of pics different ways to make up a pano.except in this case!!!
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Old Jan 27, 2006, 9:55 PM   #9
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Toshi43 I take a lot of water panos and never get banding with the
exposure and WB fixed. Are you sure the images weren't modified before
stitching and that the camera fixes everything with the first shot? I had an
Oly that fixed all of the shooting parameters with the first shot in pano
mode and never got any banding. But my Pentax had a pano mode that
didn't keep the same settings for every shot, and my results often looked
like yours with banding. I don't see how you can get that banding with the
same exposure and WB for all shots.

I think there is real world variation in a panorama that you don't want to
completely mask. One part of a lake is going to look different from another
in a wide view.

As far as things being too bright or dim with the same exposure on a wide
pano, I find that it is much easier to fix that in Photoshop than to try to get
each shot to match up without any banding.

Reanimator Looks like a lot of work. And the right side is still
different. That is a lot of WB difference to correct for.

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Old Jan 28, 2006, 4:58 AM   #10
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Slipe

it was sunset and the left side was yellow and right side not....the mist held the colour but lens couldnt pic it up very well at all, so did my best to blend it gently across. :-)
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