Hi David. It's always good to see you use the forum again
You can get fine control of the crop handles when close to the edge of the canvas by holding down the Ctrl (Cmd) key. That stops it snapping to the edge.
You can place guides and have the crop tool snap to the guides, or snap the rectangular Marquee tool to the guides and choose image > Crop.
You can relocate the grid origin to help with precise placement either of guides or corner handle.
If that doesn't help, perhaps you can be more specific about what you'd like to achieve.
I've just had a play with it, and I think using negative Canvas might be the easiest way. The setting below will crop two pixels off the left side of the canvas.
As always, Trevor, you have the answer. Thank you. I am digitising a mass of old family photos and en route a lot of cropping of borders is necessary. The problem is that I am having to work on a 15" laptop with a very high screen resolution (3840x2160 - Dell XPS15 9550) and the only way I can get fine manual border slicing is to magnify the image and thus the crop marks. This allows subtle additional movement of the crop boundaries. When I look at the whole image on screen, the slices available are coarse. The movement is rather like the difference in the way a mechanical second hand sweeps continuously as opposed to a quartz second hand moving in jerks. I will try your solution. I wish I could get back on my 27" screen but health problems make that impossible for the time being.
Thanks again for your help.
FWIW, I usually hit ctrl+A and nudge the selection with the arrows. Then image > crop. Don't know if that's more or less efficient than anything mentioned above, but it works.
The pixel distance for each nudge varies with the zoom level. I usually zoom in pretty much for things like this anyway, so then it's one pixel at a time.
Thanks. That's very helpful advice. I now have a few different ways of dealing with the problem. Thank you.
I am digitising a mass of old family photos and en route a lot of cropping of borders is necessary.
I don't envy you. I did the same with my dad's slide collection some years ago, and despite every effort to keep the slides clean, and using ICE, it was a nightmare to clean up the images with whatever version of Photoshop I was using back then. I used Ed Hamrick's VueScan for most of it, and an early Benq 35mm scanner, plus an Epsom flatbed for the medium format. Talk about a labour of love — I wouldn't ever want to have to do it all again! My family treasures those pictures though, and it was most definitely a worthwhile undertaking.
It has just occurred to me that I now live off Hammerichs Road (Rapaura NZ) which is spookily close to the VueScan creator's name.
Yes, it's a big task alright. The photos are from my 93 year mother's photo albums after her life working in many places abroad with my father. She now has dementia and is in care, and I am making photo books with photos and brief descriptive text for her to look at by herself and with others, to reminisce while she just about can. The first album was focused on her and her family and seems to give her a lot of pleasure. One feels very helpless in the face of dementia and it is nice to find some way to connect with her and bring a smile of recognition. I am going to make other photo books of her life for her to look through, and these can then form a small collection of photos in books for the family as a whole.
I am using Vuescan too, and an Epson V800 flatbed. An early decision was what type of restoration I would strive for. I have decided to try to take each photo back as far as possible to its first state. So generally I am not, for example, keeping sepia and faded prints sepia and faded. I am restoring as far as I can. This is a choice and others may do it differently. I'm not using ICE and am doing everything by hand - the healing and clone brushes have become my great friends. I can't imagine getting the same results without Photoshop - and a couple of TopazLabs plugins are helpful.