[Lordstan]

I agree with both Steve and Lance's recommendation, but with a twist. Don't send to PSA at all unless you are going to be selling them in the short term.
While I like the Type system, I don't care for the idea of certification, much like I don't care for slabbed cards or autos. If I know it's a type 1 or vintage original, why do I need to pay for someone else's opinion? If I'm not sure or if I want to sell it and feel that the cert will add significantly more to the final price, that is different.
That being said, I don't think that quality photos sell more that much less without certs as compared those with certs. If we eliminate the results from Henry's auction, which are usually well above typical prices, even in relation to the bigger auction houses, there are many sellers on ebay that get top dollar for high quality vintage photographs without any certs.
If you do go for the cert, I wouldn't worry that much about whether to slab or not to slab. A buyer who wants the picture will likely buy it either way. They always have the option of cracking the slab if they want to. I have cracked many pictures out of slabs, especially those done by Beckett. IMO, their slabs take up waaaaay too much room for just a photograph.

Best,
Mark