phreeky wrote in post #12729218
What are the odds of you using an ND filter on the 70-200 for anything other than landscapes while using a tripod? Because in those tripod/landscape scenarios you should be able to rig up something to shade the front of the lens.
Actually I don't really shoot landscape at all. I shoot almost exclusively portraits. The purpose of the ND filter would be to cut overall light so I can shoot at wider aperatures (i.e. f/4) while limited to the max sync speed of my 40D (1/250th) when using studio strobes outside. Using the sunny 16 rule, a 3 stop ND filter should allow me to shoot at f/4, 1/250th, ISO 100 and properly expose for ambient. I've come to the conclusion that I might want to underexpose ambient up to a stop, so I'm considering adding in a CPL filter which should give me another stop or so in addition to the inherent benefits of a CPL filter. The only problem is, it looks like I could easily spend $300 to get a 77mm B+W MRC 3 stop ND filter and a 77mm B+W MRC C-POL filter. Ouch!
My 24-105 is my primary portrait lens, though I do occasionally pull out the 70-200 when I am looking for extreme BG blur (and thus shoot out closer to 200mm) but I'll admit that has less usefulness as I'm limited to head shots or have to be quite a ways from my subject. That's one of the reasons I don't really want to invest in separate ND (and possibly CPL) filters for the 70-200 right now, though when/if I upgrade to a 5D that would change things quite a bit as with FF the 70-200 would now be a better portrait lens for me. The other thought is that occasionally I might want to carry my XTi and keep the 70-200 on that and the 24-105 on the 40D, so then I'm back to the same problem again.
Posts here and in other threads I've read seem to pretty much confirm that the factory hood isn't an option when using a step-up ring on the 70-200. Some have suggested buying an aftermarket filter that screws onto the filter threads, and this might be a decent compromise for now for the times when I want to use them on my 70-200. When/if I upgrade to a 5D, if I can afford to stick $2000+ into a new body, I can probably afford a couple hundred bucks more to get dedicated 67mm filter as well.