85mm f1.8 vs 24-70mm L series f2.8

Hello to all
thinking about getting one of these which is the best lens to get thanks
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Canon 30D

what do you want to do with it?

24-70 is more allaround,
85 is a specialized lens.

Price is a little different also

Get 85 1.8 and 28-75 tamron, both of them will cost less than 24-70

85 1.8 and 28-75 tamron, both of them will cost less than 24-70 but are they as goog as 24-70 ? thanks
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Canon 10D

if you can't start to answer that yourself, should you really be thinking about dropping $1200 on a lens?

the two lenses you have named are completely different beasts. You haven't stated what you envisage using them for?

The 85 obviously isn't covered by the zoom range of the 24-70 so the zoom won't replace it (despite the $800 extra in cost) - not least because it is 1 and 1/3 stops slower. The 85 is a $350 consumer lens, the 24-70 is a $1200, large and heavy pro grade L lens. It seems like an odd comparison to choose.