Luminous Landscape Forum

Raw & Post Processing, Printing => Adobe Lightroom Q&A => Topic started by: David Eichler on April 26, 2014, 07:03:33 pm

Title: Lightroom Cropping
Post by: David Eichler on April 26, 2014, 07:03:33 pm
I am trying to designate image dimensions of 1,795 x 1,287 with the crop tool in LR4.4, using custom dimensions, and I can't seem to get it
do that. Is this some kind of bug? Mac OS 10.8.5 if that matters.
Title: Re: Lightroom Cropping
Post by: Slobodan Blagojevic on April 26, 2014, 07:08:43 pm
1,795 x 1,287 is very close to 5x7 ratio, so the program defaults to that one, since it already exists in the menu of standard ratios.
Title: Re: Lightroom Cropping
Post by: David Eichler on April 26, 2014, 07:21:25 pm
Okay, well, is there a way to stop it from reverting to a default and giving true custom dimensions?
Title: Re: Lightroom Cropping
Post by: Slobodan Blagojevic on April 26, 2014, 07:40:37 pm
That would be beyond my pay grade, as they say. However, just a quick note: in the crop module you are not really giving the crop any dimensions per se, just a ratio. You can't say "Crop it to 2000x3000 pixels, please." You can, however, say "Crop it to 2x3 ratio." And then, in the Export module, specify the desired dimension in pixels.
Title: Re: Lightroom Cropping
Post by: David Eichler on April 26, 2014, 08:54:40 pm
That would be beyond my pay grade, as they say. However, just a quick note: in the crop module you are not really giving the crop any dimensions per se, just a ratio. You can't say "Crop it to 2000x3000 pixels, please." You can, however, say "Crop it to 2x3 ratio." And then, in the Export module, specify the desired dimension in pixels.

Yes, I understand that.
Title: Re: Lightroom Cropping
Post by: kaelaria on April 27, 2014, 12:14:48 am
That's not what the crop tool is for, it doesn't work with large numbers.  You have to boil it down to a ratio, that's what it's for.  Enter 1 : .72
Title: Re: Lightroom Cropping
Post by: David Eichler on April 27, 2014, 01:37:25 am
That's not what the crop tool is for, it doesn't work with large numbers.  You have to boil it down to a ratio, that's what it's for.  Enter 1 : .72

Nope. 1:0.72 gives the same in exact result as 1,795:1,287, that is, the long dimension is changed to 1,794, even though I specify 1,795 pixels when exporting. The short dimension comes out right. Why the one pixel difference on output?
Title: Re: Lightroom Cropping
Post by: kaelaria on April 27, 2014, 01:38:56 am
Because .72 is rounded.  What you want can not be boiled down to a clean ratio, simple as that.  Try Photoshop for such a specific need.
Title: Re: Lightroom Cropping
Post by: Steve House on April 27, 2014, 10:08:50 am
I'm trying to wrap my mind around why someone would care about a 1 pixel variance in image size for any practical purpose.  Can anyone actually SEE the difference?
Title: Re: Lightroom Cropping
Post by: PeterAit on April 27, 2014, 01:22:35 pm
If you need a really precise pixel dimension, use a resampling tool and not a crop tool.
Title: Re: Lightroom Cropping
Post by: James R on April 27, 2014, 03:11:35 pm
Since LR5 doesn't do what you want...
There are other options:  I would crop for composition and then take it into PS/Image/ImageSize; or, crop it in PS to your exact dimensions.