Upsizing for Printing and Large Files in Lightroom

[stockjock]

I need to print a 4222x4222 pixel file at 40x40".  My first try was to just print that file from Lightroom and the results were poor.  Noise that wasn't detectable in a 15x15" print suddenly became a big problem.  So I researched upsizing on this forum and there seemed to be a consensus that upsizing to 600 pixels per inch using either Photoshop or something like Gigapixel AI or Perfect Resize was a good approach.  So I have played around with that and run into some problems I don't understand involving Lightroom's ability to import and use the files.

1) Lightroom won't import any of the files I generated with Photoshop.  I upsized the image using PS's Image Size with 600 ppi and 40" with Preserve Details and 50% Noise Reduction.  This seemed to give good results.  But I have had trouble importing the saved file back into Lightroom.  I have saved it as a TIF, PSD, PSB and JPG file and Lightoom won't import any of them.  It doesn't seem to recognize PSB and it says the other files are too big.  I thought Lightroom was supposed to support 65,000 pixels on the longest edge?

2) Gigapixel AI also seemed to work OK (I liked PS better) but it was limited to 22,000 pixels on an edge so I created that file with two variations and saved it as a TIF and Lightroom did import those files successfully but I'm having trouble working with the files in LR.  Certain operations, like Compare, or 1:1 view seem to fail in Library mode but then 1:1 view works in Develop.  I haven't tried printing that file yet from LR.  My computer has 32 GB of RAM and plenty of disk space.

So I wanted to reach out and see if any of you could give me a better understanding of what Lightroom's limitations are and what your workflow is  upsizing smallish files to higher resolution ones and if there is a way to continue to use Lightroom to work with those files.  I guess I could just do everything in Photoshop but that isn't my preferred workflow.

Thanks.

Paul

[Rand47]

1) Lightroom won't import any of the files I generated with Photoshop.  I upsized the image using PS's Image Size with 600 ppi and 40" with Preserve Details and 50% Noise Reduction.  This seemed to give good results.  But I have had trouble importing the saved file back into Lightroom.  I have saved it as a TIF, PSD, PSB and JPG file and Lightoom won't import any of them.  It doesn't seem to recognize PSB and it says the other files are too big.  I thought Lightroom was supposed to support 65,000 pixels on the longest edge?

Are you using the “Edit In” function from Lightroom that automatically returns you to Lightroom with the new file automatically included in the catalog?  If you’re able to save the file as a tiff or psd, it should not be too big for Lightroom.

Rand

[stockjock]

Are you using the “Edit In” function from Lightroom that automatically returns you to Lightroom with the new file automatically included in the catalog?  If you’re able to save the file as a tiff or psd, it should not be too big for Lightroom.

Rand

If I use Edit In and then Save As and close PS down Lightroom shows a blank square with a message saying "Lightroom has encountered problems reading this photo"  Nothing opens when you double click on the square.  Just a blank screen.

[stockjock]

Lightroom appears to incapable of importing files I have processed in Photoshop that are more than 22000 pixels square.  I guess this is why Gigapixel limits its saved file size to 22000 pixels.  Not sure if this limit also applies to non-square files.  But even though Lightroom will import these large files it is impossible on my computer to view then at 1:1 or to use the Compare function in from the Library module.  Fortunately, you can zoom in on the file in the Develop module.  I would still appreciate learning how other people manage these limitations.

For Upsizing, Gigapixel does an amazing job as long as you are willing to accept some odd artifacts.  Retouching those out gives a much better file than upsizing with Photoshop but my guess that is very file specific.

[Bart_van_der_Wolf]

Lightroom appears to incapable of importing files I have processed in Photoshop that are more than 22000 pixels square.  I guess this is why Gigapixel limits its saved file size to 22000 pixels.

That Gigapixel AI limit is for 16-bit/channel TIFFs. When you output as 8-bits/channel TIFFs, the limit is higher. It limits the larger dimension in a rectangular file.

Not sure if this limit also applies to non-square files.

 

Yes. It limits to the same larger dimension in a rectangular file.

For Upsizing, Gigapixel does an amazing job as long as you are willing to accept some odd artifacts.  Retouching those out gives a much better file than upsizing with Photoshop but my guess that is very file specific.

Make sure that the artifacts are actually even visible in print. They often are not visible, especially when printing with a density of 600 or 720 PPI. The Gigapixel AI output quality keeps amazing me with extreme detail (even if it's fake, it's convincingly realistic fake).

EDIT: You can also check if Lightroom can import  LZW compressed TIFFs (if that's what you used). Gigapixel AI offers an output choice of compression method between LZW, ZIP, or None.

Cheers,
Bart

[digitaldog]

Lightroom appears to incapable of importing files I have processed in Photoshop that are more than 22000 pixels square.

LR doesn't support PSB files (unfortunately). The limit on PSD, TIFF isn't just number of pixels but 'size' at 4 gigs, does this document have a boatload of layers?
Can you open this problematic document, select Duplicate and resave, then will it work?

[Daverich]

Not sure where you got the idea on this forum that you needed 600 PPI but that sounds kind of high.

[Alan Goldhammer]

Not sure where you got the idea on this forum that you needed 600 PPI but that sounds kind of high.

That number is for Canon printers which natively are at 300 but can be set for 600 if you want to up rez.  The recommendation that I follow is only up rez to 600 if the image is >300 ppi.

[digitaldog]

That number is for Canon printers which natively are at 300 but can be set for 600 if you want to up rez.  The recommendation that I follow is only up rez to 600 if the image is >300 ppi.

You absolutely don't have to match those numbers and often you can't without making up pixels out of thin air (using AI or not)
Back to:

https://www.digitalphotopro.com/technique/photography-workflow/the-right-resolution/

[Bart_van_der_Wolf]

Not sure where you got the idea on this forum that you needed 600 PPI but that sounds kind of high.

There are a couple of reasons why one would do that.

• To match a printer's native resolution (300/360 PPI or 600/720 PPI) because otherwise, the printer'driver' will do a low-quality resampling to achieve that objective. If resolution is already above 300/360 PPI it makes sense to not throw that away by downsampling, but instead do upsampling.
• Resampling requires a follow-up Output sharpening (compensating for resampling losses and to precompensate for output-media losses. e.g. due to ink-diffusion), which can be done more accurately after the resampling, and at a larger scale it can be done more accurately (and with a larger amount because artifacts will not be as visible)
• Gigapixel AI creates higher-resolution detail, in addition to captured detail being larger and more free of rescaling artifacts (without e.g. jagged edges, or edge halos/ringing)

The reason why one would want to exceed the 300/360 PPI density, is because some image detail can make use of the Human Visual System's ability to have 'Vernier acuity' that allows to see higher resolution than average 20/20 vision.

Bottom line, prints will look sharper.
How much sharper, depends on the subject matter.

Cheers,
Bart

[Bart_van_der_Wolf]

To give a bit of an impression what Gigapixel AI adds to resolution, I've added 4 screengrabs (so final file output is slightly better). Two tiny crops from a church interior, and two crops from a handheld shot in the Rotterdam harbor of a floating crane shot from another ship. The source files were old TIFFs that I upscaled to 600% of the original size, and is shown on display at 100% zoom (1 output pixel for 1 display pixel). In print, the difference becomes less obvious to see because of much denser pixel placement.

The Raw conversion quality has in the mean time improved, so even better TIFF source files could have been made, but that's not the point. The point is that whatever the input, it is possible to create new detail that effectively boosts resolution, and suppresses resampling artifacts, which will thus produce superior output quality.

Cheers,
Bart

[William Chitham]

My 2 pennyworth:

Upsizing might help with lack of resolution but isn't the first thing I'd try if your goal is to reduce noise.

4222px sq at 40" is just a bit over 100dpi which is pretty marginal though you might get away with it on some images, but why not try 300 or 360 or whatever suits your printer? 600 seems like a pointlessly big jump.

William.

[Arlen]

If you are having trouble with noise after upscaling, try using Topaz Denoise AI before upscaling. The results on many images are often amazing, better than anything I've ever seen. Though there are occasional cases where artifacts are introduced, so you have to watch out for that.

[dgberg]

My 2 pennyworth:

Upsizing might help with lack of resolution but isn't the first thing I'd try if your goal is to reduce noise.

4222px sq at 40" is just a bit over 100dpi which is pretty marginal though you might get away with it on some images, but why not try 300 or 360 or whatever suits your printer? 600 seems like a pointlessly big jump.

William.

Better yet go 180 in Perfect Resize for your uprez then in Lightroom print module set your print resolution to 300/360. (We are doing all pretty large canvas so your milage may vary.)
Your tiff file size is much smaller by not going all the way to 360 in your first uprez step as setting your print resolution in the Lightroom print module is not sticky.
At least that is how we do it here and we print some really large prints and our files are kept at a manageable size.

[Bart_van_der_Wolf]

If you are having trouble with noise after upscaling, try using Topaz Denoise AI before upscaling. The results on many images are often amazing, better than anything I've ever seen. Though there are occasional cases where artifacts are introduced, so you have to watch out for that.

I agree, but wanted to add that when upsampling is anticipated, any processing that can add or exacerbate the visibility of artifacts should be scrutinized carefully. With that in mind, I see merit in first trying to let Gigapixel AI handle noise as part of the upscaling process.

I'm not talking about High ISO noise, which is more of a baked-in compromise due to underexposure. In that specific case, it could very well help to do some careful Noise reduction, and Topaz Denoise AI is looking like a promising tool if not overdone. Denoise AI could benefit from allowing processing of selected areas by offering layering and masking, something that has been requested by Beta testers, myself included.

Cheers,
Bart

[jimcamel]

I have just 'been there' on this - and I've now gotten some excellent results with LR and AI GigaPixel.  Earlier UpRes'ing using LR+PS Preserve Details 2.0 produced some horrible files and when I redid them using the AI GPX workflow the results were hugely improved.  It was difficult to see the impact on screen, but very obvious when comparing the full size prints.  AI GPX was much better.

Here is what I did after getting the really artifacted prints

I when back to my original raw files (OLY OMD-EM1 Mk II) are re-processed them a bit more subtly.  I applied some overall noise reduction, but then specific noise reduction in smooth areas like sky.  I set the sharpening back to about 13% (e.g. pretty much off) and was careful I did not overdue Clarity or Texture.  All this to ensure I wasn't creating artifacts in this first phase that would be amplified by AI GPX.  I added the vibrance and lighting as needed.

I exported the file at the cropped resolution without any resizing to a ProPhoto TIF at 16bits; no compression.  So, straight TIF file to a temp location. About 39MB.

I dragged this into AI GPX and set the output File Format to a 16-bit TIF, no-compression, maintained the ProPhoto color space.  As I am printing to HP, which is native 300, I was upsizing to a 12000x12000 pixel file (from something originating at roughly 3000px)-so I guess that's roughly 400%. To set these settings, I had to turn on Convert File Format to (YES).

AI GPX took 10+ minutes to run on a 2013 MacPro with dual AMD FirePro D500 graphics cards - e.g. I used the GPU not the CPU option.

This created an output file in the same folder perhaps 892MB in size.  I imported that back into LR in the same folder as my original.  No issues with the import.  I then turned on the sharpening (52%, Radius 1.8 and with Masking about 42). I choose these parameters viewing the image at 1:1 on my monitor and holding down the alt key while adjusting the sliders to see the impact in B&W.  A higher radius is required when you have this many pixels.

I printed this directly from LR's print module on 44" paper, at 40"; output print sharpening Matte-Medium.  Earlier on I considered Relative vs Perceptual and since I was very much in gamut on the original, I stayed with Relative.

[bwana]

I had the same problem and the 22000 pixel limit was annoying. I divided the original image into 4 panels , upresized each to maximum in TopazAI, then merged in PS. needed some editing at the seams.