Need advice on the 35 f1.4L. There doesn't seem to be any recent reviews on this one. How come? I am interested in it for photojournalism. Mounted on a 5D for true 35mm and small footprint, I think it would be an awesome available light combo for strolling in busy cities.

BUT, I already have the 24-70 f/2.8L. Yeah, it's heavier and 2 stops slower. But is the noise reduction on the 5D significant enough to overcome the 2 stops? In other words, is the noise level of the 10D at ISO 400 "equivalent" to the 5D at ISO 1600 so that I can shoot with the zoom instead of the prime?

Also, if enlargements are not going to be greater than 11 x 14 using the 5D, could I expect to see significant improvement in resolution of the prime over the zoom? I just don't know how far zooms have come and perhaps what I have is imperceptibly close to that of primes at 11x14 size prints?

I've always coveted that lens and the 24mm f/1.4L. A less expensive but worthy alternative is the 28mm f/1.8. It's not an L lens but it gets great reviews and it's still not cheap. I actually almost bought the 35mm f/1.4L once, but changed my mind and bought the 20mm f/2.8 instead. That lens has served me well, although it's not really fast. I like the angle-of-view, though.

It's easier to talk about these lenses if we stick to one format. But when you start comparing the 5D to the 10D it gets more complicated. Because the 5D is much newer than the 10D, it should have much lower noise. You can check the studio samples in the gallery and pro reviews for examples. Also, since the 5D has twice the resolution of the 10D, any noise will be effectively reduced. In other words, if they have the same amount of noise, at the same print size, the 5D will exhibit half as much noise.

And then there's the optics issues. You can't just interchange noise and lens speed. They may both affect your ability to shoot in low light. But they'll have other effects, too. The most obvious effect is depth-of-field. The faster the lens, the shallower the minimum depth-of-field. That can be good or bad. It depends on what you like and the circumstances. A faster lens will also give you a brighter view in the viewfinder. That will help shooting in low light, regardless of your exposure.

All that aside, I'd probably stick with what you've got. You have to ask yourself what the new lens will really add to your photography. If you find you're always trying to shoot at a larger aperture, regardless of your ISO setting, then the new lens might be the right thing to do. If that's not the case, then your current lens is probably fine for your needs and style.

Thanks, PJ

That helps me understand better the noise comparison between the 5D and 10D. I'm still trying to get over my tendency to always shoot at ISO 100 which is much faster than what I'm used to with Kodachromes and Fujichromes. Without being able to change out 35mm film easily (although I did it mid-roll whenever necessary as long as I had a pen and a Post It note handy), I usually shot with slow film and a fast lens. For me, using a wide aperture and narrow DOF was often the by-product of using my preferred finer-grained film. I never once used film faster than 400 (not even pushed).

I think that I will buy the 5D, stay with the 24-70, and use ISO values in the 800~1600 range (ooh). If the noise is too great for my liking, I can always but the faster prime later.