Photomerge: swapping merged images

[Guy Burns]

I'm photomerging slides that were taken as panoramas in the 1980s. One of these panoramas is rather dark and won't photomerge, but if I lighten the images, then they will. I want to keep the original dark tones, and I'd rather not lighten (for the photomerge), and then darken. I'm a bit of a purist in regards too many edits.

Is there a way I can apply, say, a Curves layer, and photomerge with the Curves layer intact? Or any other technique?

If not, what is the most reversible way to increase brightness and then revert? Reversible meaning ending up as close as possible to the original brightness.

As an aside: why is that my slide panoramas so readily photomerge, sometimes with only 5% overlap, whereas digitals seem to require a lot more overlap?

[c.pfaffenbichler]

»Is there a way I can apply, say, a Curves layer, and photomerge with the Curves layer intact?«

I don’t think so. 

»If not, what is the most reversible way to increase brightness and then revert?«

I would recommedn using Curves and working in 16bit at least. 

Inverting the Curves’ effect can be done fairly well with another Curves application, to figure out the necessary numbers one can experiment with Curves Layers. 

How many images in how many panoramas are affected? 

Might it be easier to warp a Smart Object of the original into the arrangement? 

[Guy Burns]

Thanks for the suggestions. Looks like I'll edit the brightness before I photomerge. I might give the warp idea a go as well.