My own sign language skills are minimal, but enough so that I can ask permission to photograph the conversations that go on near the church which has sermons for the deaf. If the signers seem particularly animated, I stop and ask with faltering language whether I can take pictures… and I have never been turned down. The only problem is that they usually turn and pose just like everyone else, and I then need to explain in sign language – no, just like before. Forget that I’m here.
Frankly, not being able to hear the camera go off, they’re better at this than the average person. Afterwards, I spell out – thank you so much – and just like anyone that sees you make the attempt to speak their language – they are usually very gracious. Same experience I had in France – where I had been warned about the “snooty” Parisians, but I spoke enough to make myself understood, and that was all it took to feel accepted.