Quote Originally Posted by R.Gould View Post
I find that with HP5 in Rodinal, either 1/50 or 1/25 it loses a lot of speed, it is only with Ilford film I have this problem, using Kodak or Foma I lose about 1/3 of a stop, I don't know why, but with Ilford I only get around 320 even in D76, that goes for all Ilford film, Quality is fine but it seems to lose a lot for me, but it is a few years now since I have used any Ilford, prefering Kodak Tri x or Fomapan 400
That's interesting. I see a lot of people shoot HP5+ at 800 and soup it in Rodinal 1+25 and get really great looking prints from it.

If the OP shot the film at EI 25-50, then all he needs to do is to cut the development time a good bit. By how much is a bit of a guess, because it's about 3-4 stops overexposure compared to box speed. This is why I suggested to shoot one more roll at the same speed and test it first, especially if there are important photos on the other roll. My opinion is that it should be salvageable, and the resulting prints may even be fantastic, but perhaps a little bit lower in contrast than normal.