85mm f/1.8 vs. 35mm f/2.0

I'm going to pick up a new lens today and I've narrowed it down to these two. My lineup is currently lacking a good prime and anything faster than f/2.8. I can easily use either of these focal lengths, so that's not a deciding factor. I'd really appreciate any input from anyone who has used both these lenses (preferably on a crop body). My other lenses are the 24-70L, 70-200 f/4L IS, Zeiss 135mm f/2.8, and 50mm Compact Macro.

Thanks for your input

It looks like you actually need something short, but I wouldn't go for a 35mm f2...
You have the 24-70, and I don't think it's worth buying anything slower than 1.4.
So, if the 35L is too expensive, you can go for the sigma 30 1.4 (as far as you get a good sample)

Anyway, 85 is a great lens too...it's just a matter of mm. I have no idea of the FL that fits best your needs!

Luca

I've used the L counterparts of the lenses that you're considering and found that on a crop body I much prefer the 35mm focal length. I've found that between the two focal lengths I'm much more likely to pick up the 35mm because it works in so many circumstances.

The 35mm is loud, but it is tack sharp (at least on my copy), and I keep it on my camera about 60% of the time.

I have both. The 85 is better outside, where you have more light. In my house, I find that I need to bump the ISO up to 3200 get adequate shutter speeds with the 85.
On my XS, the 35f2 seemed sharper. I just got a T2i, and the 85 is better than it was, and seems a little sharper than the 35 (on the T2i). Indoors, the problem is space and lighting. The 35 shines inside, and is equally useful stopped down.
The shorter focal length is more useful indoors and in a wider variety of situations. The 85 is a nice lens, with good contrast and is certainly sharp.
You will use the 35 more than the 85 - I think.
I attached a couple of shots. The runners were taken with the 85 on the XS.
The street shot was with the 35 on the T2i.
Both shots were cropped and resized, but are jpegs out of the cameras.

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