Editorial / Photoshop Question

[richdlc]

photoshop question for the hive mind...

I'm trying to manipulate a jpeg image for an upcoming book in PS. I want to use the marquee tool to cut and paste part of the image into a new layer, and then adjust the light levels using curves. The trouble is, if I then try and clean it up using the eraser tool I can't merge layers, and I certainly can't save and export the image (seemingly any format but I would prefer to export as a jpeg), I get an error message 'Files can not be saved - program error'. I'm scratching my head here...I understand that the error message is just a warning (something to do with jpegs, compression etc) but is there any way to override it, and still end up with an edited jpeg? I can perform other functions that don't involve layers and save the results no problem...

[Nick Beale]

I've just tried this (in Photoshop CS5 on a Mac running OS 10.14.6) and had no trouble at all. I wonder if it's a problem with the particular image?

Is there a particular reason not to carry out the adjustment on the main layer? (Saving a backup first, of course). If you select part of the image with the marquee tool— feathering the edges if desired—and then open the curves or levels adjustment dialogue, any changes you make will only take effect in the area selected.

[richdlc]

thanks Nick. Usually I would just use features such as curves on the main layer. I just thought I would try something new, make a copy (and edit it) and then blend the two together and save it as a jpeg. I will look into it further but for now I will just try adjusting levels on the main layer. It may be an issue that affects the very latest edition of Photoshop...it's weird whatever it is.