Canon EF 28-135mm f/3.5-5.6 IS

[Steve Parr]

I need a very basic education here, if someone would be so kind.

On the EF 28-135mm f/3.5-5.6 IS, with the IS turned on, at f/3.5, what would be an equivilant f-stop (number, please) on a non-IS lens?

Also, is there any reason under the sun this lens wouldn't work with a 300D?

Thanks!

Steve

[rent]

turning on IS would have no effect on aperture values. a f/3.5 on an IS lens (with IS on or off) is the same as f/3.5 on non-IS lens.

what IS allows you to do is shooting at a slower shutter speed (maybe 2-3 stops slower), which means, to keep an identical exposure (allowing same amount of light to hit the sensor), you can decrease your aperture value by 2-3 stops.

it should work on your 300D just fine.

-alex

[FlyingPete]

turning on IS would have no effect on aperture values. a f/3.5 on an IS lens (with IS on or off) is the same as f/3.5 on non-IS lens.

what IS allows you to do is shooting at a slower shutter speed (maybe 2-3 stops slower), which means, to keep an identical exposure (allowing same amount of light to hit the sensor), you can decrease your aperture value by 2-3 stops.

it should work on your 300D just fine.



IS pretty much saves you a tripod in certain situations, it allows hand held on the 28-135 around two stops lower than otherwise (IS is better on newer lenses), so you should get away at 1/60 at 135mm, I can get away at 1/60 on my 75-300IS at around 135mm.

What it doesn't help you with is subject movement, only a faster shutter will save you there!

[Steve Parr]

"And quietly, yet suddenly, Steve begins to grasp the concept..."

Thanks everyone...

Steve