I'm looking for a ring flash to use for fashion, etc. All I'm finding is a ring flash "not recommended for digital SLRs". This include's Canon's ML-3, a cheapo Phoenix model, and the Vivitar 6000AF. What happens if I put it on a D30 or D60 (the body I should be getting in the next couple of weeks)? Will I just lose TTL?

Also, my 28-70/2.8 is a 72mm filter size. I haven't found a ring flash with an adapter bigger than 58mm. What gives? Will I have to buy another lens just to fit this flash? It doesn't seem like it's worth it. Thanks for any help!