I was thinking about using a Canon "L" series 70-200mm f/2.8 lens with a Letus. Seeing that the f stop is a constant across the zoom range and the Letus Extreme looses only half a stop...

I realize that the aperture will be fixed at f2.8 since this is an auto focus lens.

Quyen says there is no problem using a zoom and so I was wondering if anyone was already doing so and if so if there are any clips I can see.

I have a set of rails as well and so supporting the rig (lens, Letus Extreme etc.) shouldn't be a problem (3lbs for the lens and 3lbs for the Letus Extreme).

Any reason why I shouldn't be using a zoom?

Thank you for any replies/suggestions.

Shiv.

check this clip by disjecta

http://www.pinelakefilms.com/XHA1/zoom.wmv

He used a cheap Tamron lens (with Canon EOS/EF fitting, the only zoom he had available). It's a 28-80mm f3.5-5.6 and has some serious softness on the edges...it is also soft around the edges when using it with a still camera so don't judge sharpness.

The weather was dull and wet and he was shooting out an office window with lots of reflection. He posting this because he want to demonstrate that there is no vignetting when using a zoom lens.

David,

Thanks for the link. disjecta is Steven Demsy no?

I guess I'll have try for myself. With a good lens and good light.

Shiv

Yup, he is,

I think it should work fairly good. I mean F2.8 if faster then the lens that disjecta used. Should work out fine.

I'm ordering mine soon before it goes up to $1500. By the way they are also giving out a free support bracket worth $50 for buyers that order now. I think it is a pretty good deal. Can't ask for more.

Thanks for the heads up!

I didn't see that before. I guess diameter (15mm) of the rods on the rails are "standard"?

I have an older F 3.5 43-82 mm Nikkor that I just bought on EBay, and will be trying it out on my Letus 35a. I will keep you posted on what results are. I have already had on it briefly, and noted vignetting may create some issue..

Chris,

Thanks. Yes, please keep me posted.