Help with custom cropping and known aspect Ratio's

Question

I would like to crop a small part of a larger image with custom / free flow dimensions to the crop and then be able to print / export at a know print friendly aspect ration. An example would be a taking a crop of one person in a couple,from a larger image. The crop is outside common aspect ratios. Can lightroom fit the image to an aspect ratio of my liking whilst maintaining everything I have cropped?
Thank you in advance

Answer 1

Clearly we can't get one aspect ratio into a different aspect ratio without either trimming bits off, or else leaving gaps.
So the best I can suggest is: crop in Develop according to the subject content that you don't want to see.
Then in Print, set up your print layout (or choose a print template) which contains an image cell of the desired size and shape.
There are two ways that a photo can be put into such a cell: it can be fitted "loose" so that you always see the whole current crop, leaving white margins as required; or else it can be fitted "tight" using the Zoom to Fill checkbox. In the latter case, LR applies an additional print-only crop which forces the image that is seen, to adopt the shape of the cell. So the aspect ratio of the Develop crop, does not need to have been exact for this precise output.
This print-only crop will only remove further bits of the photo, not put any back - unlike the Develop crop. But you can slide the image around for the best composition, in terms of what it trims off.
Your main (Develop) crop has not been altered in any way by doing this, and can of course still be adjusted further also, which will in turn alter how the zoom-to-fill appears.
[ edit add: The Develop crop might be made specific for a particular print shape, but does not have to be, with the above technique. Maybe one actively wants to retain the camera-original aspect, with other kinds of output in mind. In any case, page margins often mean that the actual printed area is not quite exactly the same shape as the notional page anyway - a "10x8" printed with a half-inch margin on three sides and a three-quarter inch margin on the bottom, would print 9" x 6 3/4" (which is a different shape than 10x8). And all that would need to have been worked out each time, re-cropping the main composition for each different output size, margin width, etc then re-cropping it back again to 3:2 (or whatever) for your web upload. That can be managed through presets, virtual copies, snapshots - but sounds like a lot of extra work to me. My own images are cropped for general purposes, but each one remembers its last print settings also - which places it onto a page in the needed manner.]