Oh dear, oh dear, oh dear! No easy solution and the hard way is going to be very hard!
Not much to work from when you get to his arm. The only thing I can suggest is to work on clearing the small and easier areas first to give you a bit of source material to clone from.
Sometimes when attempting items like this for my local history society I manage to clone from another person but even that isn't an option here.
Hi,
I don't think that there are any easy solutions to your problem. Having said that, I have at time had success in reducing the brownish stain on old black and white photos by using a channel mixer adjustment layer to add the best of the three channels and substract the worst one to create a new black and white image. You might have to play with the proportions of each channel but sometimes the stain disappears completely. Most of the time you will still have to touch up the resulting image but the job should be much easier.
Best of luck,
André
P.S. Here is a quick sample of this method followed by a bit of local contrast enhancement. You would still need to do the final cloning and healing.
Last edited by Round Tuit; 20th January 2017 at 01:35 AM. Reason: Add picture
Good job in tidying it up. The colour seems to have changed a bit with a slightly green tinge. That may be your desired look of course.
Dave