Technical Question...

For a while now I've looked at my lenses (zooms) and wondered why they aren't faster on the wide end. For example, my 70-200mm f4 L is capable of opening up to a 50mm aperture at the long end, so why can't it be that wide at 70mm? That would make it f1.4 at the wide end, and that would be AWESOME.

What is the reason that this isn't possible? I'm sure there's a good reason, but rather than sitting down and puzzling it all out, I'm just going to ask on here. I'm sure there is someone else here who wondered the same thing and decided to do all the math.

Its a weight issue, for the lens to be able to open to f1.4 they would need to fit 2.8 times as many homunculi inside the lens which would make it heavier, the binding spells would be more complex and it would just end up being to expensive. Also if you dropped it, they'd be picking you up with a shovel.

Now someone give him a serious answer

BearSummer

One reason, It is attractive to have fixed aperature zooms. Makes life so much easier for the user. Also, you know the elements inside are moving aorund as you zoom. Suppose the first element inside was further away at 70, then it couldn't be more than f/4. If you get ny drift.

gasrocks wrote in post #2057584
One reason, It is attractive to have fixed aperature zooms. Makes life so much easier for the user. Also, you know the elements inside are moving aorund as you zoom. Suppose the first element inside was further away at 70, then it couldn't be more than f/4. If you get ny drift.

Gotcha... I guess that makes sense in the same way that a 10-22mm lens is twice as long as my 50mm...