# Panorama problem



## inmyprime (Sep 28, 2016)

When I try to stitch a panorama in Lightroom CC, one side of the finished panorama is underexposed and the other side is overexposed (I haven't made any adjustments to the original raw files before stitching). LR seems to adjust exposure of the photo in the background and I can't seem to find a way to switch off this function.
I attach the stitched photo to show what I mean. I must be missing some simple switch somewhere.
It looks as though some adjustment has been made but when I click "reset" in develop module, nothing apart from crop, changes. Any ideas


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## clee01l (Sep 28, 2016)

What camera settings were used to take the individual images?  Auto Aperture, Auto Shutter, Manual?  Are the images adjusted in any way in LR before sending to Pano Merge?  Are the original images RAW or JPEG? Can you post screen shots of the first and last image from LRs Loupe View?


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## inmyprime (Sep 28, 2016)

No adjustments made to RAW images prior to stitching. Shot in Aperture priority or Manual mode if I remember correctly (will check). Exposure of first and last image looks perfectly fine on individual images before stitching, but it's really messed up on the stitched image. Since it's the first time I used the Pano tool in LR, I thought I checked some box somewhere to auto adjust exposure but from your response it seems that there isn't such a box which makes me think it's a bug? I will post screen shots tomorrow when I am back at the computer. I will also try PS pano feature and see if it makes a difference to final image.


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## clee01l (Sep 28, 2016)

I tried different scenarios with Pano.  It looks like the Pano tool takes its adjustment settings from the first image in the series.  If I severely under expose this image or severely overexpose the first image. The resulting Pano is under or over exposed accordingly.   Raw Images are adjusted when demosaic'd and converted to RGB.    All of my NEFs are very nearly the same exposure and I see no differences.   Your image looks like the sun was in the right most images and might have been shot with different auto settings. If the first image was the left image and it was underexposed, then adjusted with a 1 to 2 stop higher exposure, then that might has been propagated to the overexposed right most image.   

I'm thinking there is a way to process this in LR but the LR Pano tool is pretty generic.


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## inmyprime (Sep 28, 2016)

Thanks. So I checked the settings: they are all the same for all 12 images so must have been manual mode (ISO100, 75mm, f9, 1/125sec). I used polariser and (possibly) graduated filter for sky. Although looking at the images, it looks as though I may have forgotten to rotate the filter when switching to vertical framing for panorama (embarrassing!). Could this throw off LRs algorithms and make them go darker/brighter towards each side?

Attaching 1st and last picture of the stitch. Exposure looks fine across all 12 images but each image has a slightly darker left side which makes me think that i forgot to turn the graduated filter...The sun was not stronger on the right. I will try PS.


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## inmyprime (Sep 28, 2016)

So when I tried this in PS, it has produced a much more even result. However it has vignette control and a couple of more check boxes. I guess better to use PS then...(and to remember to turn the filter next time).


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## tspear (Sep 28, 2016)

Check if you have the auto-tune turned on the Pano in Lr. This has sometimes created really odd results.
Also, I am fairly positive that Lr ignores all edits and uses the raw data to stitch the pano together. Therefore, when comparing the images in the loupe view, make sure you are reviewing the raw image, not adjusted.
This has happened a few times for me, and usually is the result of a brighter exposure to one side of the image, it can be as little as one or two stops and that gives it a washed out feel. My solution has been to use a graduated filter to correct.
If I need to adjust more then 2 stops or I have a large dynamic range (usually caused by the sun) the technique I am trying now (and have mixed results) is to create two pano's which I then merge via HDR. Each pano is at a constant settings in manual mode, one pano set for the brightest area, one for the darkest area.


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## Hal P Anderson (Sep 28, 2016)

Using a polarizing filter with a wide angle lens where the sky is in the image often produces images that don't look right, because the light coming from the sky is polarized differently at different angles from the sun. Part of the sky is darkened much more than other parts. This effect may be contributing to your problem.


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## inmyprime (Sep 28, 2016)

You mean the auto tone? This options seems only to be available in HDR Merge in LR, not Panorama (I only see auto crop).

"If I need to adjust more then 2 stops or I have a large dynamic range (usually caused by the sun) the technique I am trying now (and have mixed results) is to create two pano's which I then merge via HDR. Each pano is at a constant settings in manual mode, one pano set for the brightest area, one for the darkest area."

Interesting technique.

"Using a polarizing filter with a wide angle lens ..."

This was shot at 75mm. I think I forgot to turn my graduated filter into vertical position...PS seems to handle this better and it totally seems to throw LR off.


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## tspear (Sep 28, 2016)

inmyprime said:


> You mean the auto tone? This options seems only to be available in HDR Merge in LR, not Panorama (I only see auto crop).


You are correct, I was thinking of HDR. I have been doing more HDR recently then pano's and got the screen options backwards. 

You should also note that the Ps has been around a lot longer and is in a much more mature state.


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## clee01l (Sep 28, 2016)

I think you have answered your own issue. The 75mm lens in not a wide angle, so the distorted polarizing effects won't show up.  However having the polarized filter at 90˚ would tend to produce the results that you see on the individual frames.   You might remove the polarizing effects on each image by using the ND tool  and then merge them with the pano tool. Remember the Pano tool in LR is fairly basic and only handles generic cases well.  PSCC will always have better tools to manage these images.


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## Hal P Anderson (Sep 28, 2016)

My point (perhaps insufficiently explained) was that creating a panorama gives the same kind of result as shooting with a wide angle lens. The end result covers a large angle of view, and the polarizer will respond in the same way in both cases. The polarizing effects won't show up within the individual frames, but _will_ be apparent in the pano.


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## clee01l (Sep 28, 2016)

Hal P Anderson said:


> My point (perhaps insufficiently explained) was that creating a panorama gives the same kind of result as shooting with a wide angle lens. The end result covers a large angle of view, and the polarizer will respond in the same way in both cases. The polarizing effects won't show up within the individual frames, but _will_ be apparent in the pano.


I see where you are coming from.  By pointing the camera at different angles wrt the sun, you are in effect, "curving" the composite lens. If the polarizing filter is adjusted correctly for the direction of the camera wrt the sun angle, you will minimize the glare caused by the sun bouncing off of objects and into the  camera lens.  Since the direction of the camera is changing for the composite shot, you would need to stop between each shot and change the polarizing filter.   A curved wide angle lens has the same problem but with out the ability to optimize the filter for that part of the lens wrt the sun angle.


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## Cerianthus (Sep 28, 2016)

Point the op made he was using a graduated filter, not a pola. 


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## clee01l (Sep 28, 2016)

Cerianthus said:


> Point the op made he was using a graduated filter, not a pola.
> 
> 
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From the OP:


inmyprime said:


> I used polariser and (possibly) graduated filter for sky.


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## inmyprime (Sep 28, 2016)

I used both polarizer and graduated filter I think (I tried out the new Lee filter holder for the first time and in switching quickly between horizontal/vertical composition may have accidentally forgot to turn the graduated filter). Still, I am a little surprised the way LR handles it; you can barely see the graduated effect on the individual images but perhaps it amplifies LR's auto-adjustment algorithms creating this crescendo towards the sides of the final stitched image.


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## Cerianthus (Sep 28, 2016)

My bad misread that. 


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## themoose (Oct 4, 2016)

I had a similar problem using a polarizer so I never use one now for any panos. In my case the sky was very uneven and struggled to fix it in LR with a gradient filter.


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