Luminous Landscape Forum

Raw & Post Processing, Printing => Adobe Camera Raw Q&A => Topic started by: MichaelEzra on April 07, 2018, 02:23:01 pm

Title: ACR - Merge to Panorama - low res
Post by: MichaelEzra on April 07, 2018, 02:23:01 pm
Using latest ACR 10.3: Merge to Panorama - results in a low resolution file - e.g. instead of 130 MP ACR renders 50 MP.
Is this expected behavior with ACR?
Title: Re: ACR - Merge to Panorama - low res
Post by: Redcrown on April 08, 2018, 11:42:21 pm
Point of clarity - ACR does not do panorama merge. ACR simply passes converted raw files to Photoshop and Photoshop does the pano.

I can only guess that you have ACR set to resize/downsize, and are thus passing smaller images to Photoshop. Check and click on the "Workflow Options" at bottom center of the ACR window.
Title: Re: ACR - Merge to Panorama - low res
Post by: Schewe on April 09, 2018, 01:26:51 am
Point of clarity - ACR does not do panorama merge.

Actually, both ACR and Lightroom do indeed do both Pano Merge and HDR merge without the use of Photoshop...the resulting merged image is a linear DNG file that retains raw processing capabilities.

As for the op, look at the image in pixel dimensions and not file size. File size is a very inaccurate measurement of image resolution.
Title: Re: ACR - Merge to Panorama - low res
Post by: Redcrown on April 09, 2018, 02:06:04 am
Actually, both ACR and Lightroom do indeed do both Pano Merge and HDR merge
Sorry, senior moment. I do panos so rarely I didn't think. I just selected pano from Bridge, not ACR, to look from some reason the OP was getting small files.
Title: Re: ACR - Merge to Panorama - low res
Post by: MichaelEzra on April 11, 2018, 04:28:23 am
As for the op, look at the image in pixel dimensions and not file size. File size is a very inaccurate measurement of image resolution.

I am referring to resolution. ACR produces panoramic merge image of a much smaller resolution than Autopano, comparing the same projection/geometry.
Title: Re: ACR - Merge to Panorama - low res
Post by: Bart_van_der_Wolf on April 11, 2018, 04:48:11 am
I am referring to resolution. ACR produces panoramic merge image of a much smaller resolution than Autopano, comparing the same projection/geometry.

Hi Michael,

Is it only smaller than Autopano produces, or is it much smaller than the initial tile sizes (minus overlap) would suggest it could be?

Cheers,
Bart
Title: Re: ACR - Merge to Panorama - low res
Post by: MichaelEzra on April 11, 2018, 06:58:43 am
Hi Bart, much smaller. On one example with a 5 D800e frames Autopano stitches 130 megapixel file while ACR only 50 megapixels.
Title: Re: ACR - Merge to Panorama - low res
Post by: Bart_van_der_Wolf on April 11, 2018, 07:26:39 am
Hi Bart, much smaller. On one example with a 5 D800e frames Autopano stitches 130 megapixel file while ACR only 50 megapixels.

Okay, 130MP for a 5 image stitch seems about average for something with an approx. 30% overlap, so 50MP is way too small.

Strange indeed.

Cheers,
Bart
Title: Re: ACR - Merge to Panorama - low res
Post by: TonyW on April 20, 2018, 07:20:41 am
Using latest ACR 10.3: Merge to Panorama - results in a low resolution file - e.g. instead of 130 MP ACR renders 50 MP.
Is this expected behavior with ACR?
I have not done that many panos using ACR in particular but FWIW a 7 NEF pano from D800E each NEF around 45 MB. 

Merge to Pano in ACR resulting in a 14841 x 6736 pixel DNG file of 373MB (16 bit ProPhoto 300 ppi). 

So your file size seems to indicate lower than normal.  Could you have set the Workflow Image Sizing to less to account for the smaller than expected file size?
Title: Re: ACR - Merge to Panorama - low res
Post by: MichaelEzra on April 20, 2018, 02:09:07 pm
That's the thing, I didn't downsize the images in workflow options. ACR just produced a small output pano.

Just watch out using this feature, until it gets fixed...
Title: Re: ACR - Merge to Panorama - low res
Post by: Schewe on April 20, 2018, 05:00:27 pm
Just watch out using this feature, until it gets fixed...

On YOUR system...merge to pano is working fine on my machines.

You still haven't stated the pixel dimensions...file size isn't a useful unit in this case.
Title: Re: ACR - Merge to Panorama - low res
Post by: MichaelEzra on April 20, 2018, 05:43:00 pm
I never mentioned file size. Original post refers to MP= megapixels :)
Title: Re: ACR - Merge to Panorama - low res
Post by: TonyW on April 21, 2018, 06:12:26 am
I never mentioned file size. Original post refers to MP= megapixels :)
Hi Michael,
Being curious I had a quick play my conclusion from this was that there are no issues at all with the way Adobe implements merge to pano at least on my system (Win 10 64 bit, latest ACR). 

Autopano obviously works quite differently taking a lot more time to render but the main difference seems to be the production of TIFF (or other rendered file) rather than the raw/linear DNG produced by ACR or Lightroom.

FWIW, my play details From  7 NEF cylindrical projection:

ACR produced DNG = 15028 x 7981 pixels (120 MP).  File size = 374 MB

Autopano TIFF =  15307 x 8017 pixels (123 MP).  File size = 936 MB

Autopano TIFF (Remove Alpha Channel) 15307 x 8017 pixels (123 MP).  File size = 702 MB

When opened in Photoshop:

ACR created DNG pano opens as a raw image first then reported image size = 686.3 MB

Autopano TIFF both 702.2 MB

Title: Re: ACR - Merge to Panorama - low res
Post by: mcbroomf on May 01, 2018, 06:19:46 pm
I know this is a slightly old thread but 2 questions for Michael.

When you open a single file from ACR into PS what pixel dimensions do you get (ie you should get 36MP from D800 ... do you)?
  This will tell if you have a setting in ACR that is reducing the output

Do you have auto crop set in ACR and not in AutoPano?  I get 116MP  vs 122MP  depending (both in ACR from a 6 shot vertical with 42MP sensor .. have not checked in AP), and that is on a pano with only slight cropping (ie not much white space)

Would be interested to hear if this was resolved
Title: Re: ACR - Merge to Panorama - low res
Post by: MichaelEzra on May 01, 2018, 06:49:11 pm
Hi Mike,

Yes, each frame is 36 megapixels, each 7360x4912.

No resizing in any ACR settings is used on example below.

Here are screenshots illustrating the issue. I can't recall which on which specific images, but I've seen much more dramatic difference in final pano pixels sizes, which I indicated in the original post.

Title: Re: ACR - Merge to Panorama - low res
Post by: mcbroomf on May 01, 2018, 07:20:19 pm
Yes that is bizarre. 

Do you have a different camera files (past or present) you can test to see if it's a PS/ACR bug? 
Delete preferences?
Re-install PS?
Can you check with LR Classic CC?
Title: Re: ACR - Merge to Panorama - low res
Post by: MichaelEzra on May 01, 2018, 08:34:32 pm
It is ACR bug, as pano merge is done within ACR, outside of Photoshop.

I didn't yet try to clear preferences or reinstall and I don't use Lightroom...
Title: Re: ACR - Merge to Panorama - low res
Post by: mcbroomf on May 01, 2018, 08:49:37 pm
....
I didn't yet try to clear preferences or reinstall and I don't use Lightroom...

I think that's the next step.  The D800e is not an uncommon camera and I think there would have been an official bug reported to Adobe if files from it were a problem with ACR panos.  I checked and did not find a report (my search skills may be lacking).
Title: Re: ACR - Merge to Panorama - low res
Post by: TonyW on May 02, 2018, 12:12:37 pm
...
Here are screenshots illustrating the issue. I can't recall which on which specific images, but I've seen much more dramatic difference in final pano pixels sizes, which I indicated in the original post.
It will be interesting to see if reset preferences or uninstall does anything.  But looking at your posted images the reported sizes do not look unreasonable to me at least in the long dims of the pano.  Short dims ??

Your image sizes shown indicate a print size of 35.61" x 18.67" @ 300 ppi.  Giving pixel dimensions of 10,683 x 5,601 pixels equating to 59.8 MP.  Therefore the overlap ACR is using is around 45%.  What does appear strange (to me at least) is the dimensioning of the short side that seems to indicate much less than I would expect without some cropping from your side!

FWIW, just tried a 4 image D800E NEF cylindrical pano (attached) which reports a print size of 35.63" x 25.63" @ 300 ppi.  Pixel dimensions 10,689 x 7,689 (84+MP).