Lightroom Classic 9.3: Export file resolution

  • 1
  • Problem
  • Updated 2 weeks ago
  • Not a Problem
  • (Edited)
Exporting jpegs to disc. By default resolution set to 300 ppi. When I try to change this the number becomes highlighted in red. Try to complete the action and get a message says this must be a number between 1 and 23 !! Had to start again and leave output resolution at 300.

Windows 10
Photo of Dave Castle

Dave Castle

  • 3 Posts
  • 0 Reply Likes

Posted 2 weeks ago

  • 1
Photo of Andrew Rodney

Andrew Rodney

  • 1044 Posts
  • 231 Reply Likes
Can't replicate on my Mac. Can you post a screen capture when you do see the red highlight so we can see all the other settings? 
Photo of Bill

Bill

  • 258 Posts
  • 38 Reply Likes
Output resolution is just a number stored with the file, it has no effect on the output quality. It's time to delete this setting from Lightroom. It is left over from the old days when it was used for printing. With modern software, that's controlled by the printer driver. Maybe some folks still using MS DOS would miss it.
Photo of Tom Mickow

Tom Mickow

  • 514 Posts
  • 210 Reply Likes
Mostly agree if you're resizing by pixels, but the resolution setting does come into play when you're resizing by in/cm.

An export of a 100x100 pixel image, resized by inches - 

10" x 10" @ 1 ppi = 10 x 10 pixel image exported
10" x 10" @ 10 ppi = 100 x 100 pixel image exported
10" x 10" @ 100 ppi = 1,000 x 1,000 pixel image exported

but resized by pixels...

10px x 10px @ 1 ppi = 10 x 10 pixel image exported
10px x 10px @ 10 ppi = 10 x 10 pixel image exported
10px x 10px @ 100 ppi = 10 x 10 pixel image exported
(Edited)
Photo of Tom Mickow

Tom Mickow

  • 514 Posts
  • 210 Reply Likes
As Andrew said, a screenshot of your export settings would help clear this up, but taking a stab without that...

Unless it's changed recently, LrC has a pixel limit of 65,000 in either dimension (width or height) and also a 512 megapixel limit.  I'm going to guess that you're trying to resize in inches while also setting a resolution value which would put the resulting image over those limits.

If you're setting the physical dimensions by length and the resolution setting, the following constraints come into play - 

length x resolution must be <= 65,000
width x resolution must be <= 65,000
(length x resolution) x (width x resolution) must be <= 536,870,912 (512 MB)

I'm also going to guess that you're not intending on making images that are that large and are confused by the settings in the export dialog.  If you gave us some more details on what you're trying to do, I'm sure somebody could help you out with the proper settings.
Photo of Dave Castle

Dave Castle

  • 3 Posts
  • 0 Reply Likes
Very many thanks for your replies. I appreciate your attention. Have to say I am no expert, just wanted to let Adobe know there might be a problem. 
Will try and post screenshots of the dialog boxes ........

Thanks again
Dave

The actual job I was trying to do was to export 19 Olympus raw files each about 4600x3500 pixels to jpegs of the same pixel dimensions at 360ppi.
Dave
(Edited)
Photo of Andrew Rodney

Andrew Rodney

  • 1044 Posts
  • 231 Reply Likes
What version of LR? I see there was a bug in the past on Windows:
https://feedback.photoshop.com/photoshop_family/topics/invalid-constraint-size-error
I simply cannot get this to show up no matter what I set anywhere in this dialog, I'm on a Mac with the latest version of LR. 
Photo of Tom Mickow

Tom Mickow

  • 514 Posts
  • 210 Reply Likes
Yep, looks like my guess was correct.  They're greyed out, but your resize settings are set to generate a 1000 x 1000 inch image...at a resolution of anything over 23 ppi, you'd cross the 512 megapixel limit.

Check the Resize to Fit box and change the W: & H: to something more reasonable and then you'll be able to set the Resolution field.

Without the Resize to Fit box checked, I would think it would ignore those fields, but obviously that's not the case.
(Edited)
Photo of Dave Castle

Dave Castle

  • 3 Posts
  • 0 Reply Likes
Spot on Tom! I am now on the naughty seat. Didn't read everything did I (just getting sloppy in my dotage).

Very many thanks
Dave
Photo of Andrew Rodney

Andrew Rodney

  • 1044 Posts
  • 231 Reply Likes
But at least in his screen capture, Resize is grayed out. 
1000x1000 inches at least on Mac, can't even be entered before one sets resolution without popping that dialog. Maybe differing on Windows? 
But indeed, 1000x1000 INCHES at even 72PPI can't be done without the warning. That is just too large a document. 
Photo of Tom Mickow

Tom Mickow

  • 514 Posts
  • 210 Reply Likes
I don't have a Mac to verify, but I think Mac/Win might be the same.  I can't set the dimensions to 1000x1000 inches immediately either.  I have to set the resolution below 24 before changing the dimensions.  Reverse is true too.  Basically, no matter what order I do things, if any combo throws me over the 65,000 dimension or 512 megapixel limit, it throws the warning.

The weird part to me though is the behavior when Resize is unchecked.  In that case, I wouldn't think there would be any need to apply a constraint to the Resolution value.  You'd be exporting at the original dimensions with the different resolution value being written to the metadata, which to Bills point, is mostly useless.