Technical Question on Canon EF 55-200mm f/4.5-5.6 II USM

[zakmckracken]

I have a Digital Rebel 300D and I recently bought a Canon EF 55-200mm f/4.5-5.6 II USM lens to complement my "KIT" 18-55 lens. I chose this lens over the (in)famous Canon EF 75-300mm f/4-5.6 III because of all the reviews and sample pictures around.

All in all I am very pleased with it, its very fast and sharp.

My question is... On the Canon website it says:

"(this lens is) ... ideal for digital SLRs–when used on the EOS Digital Rebel, it’s equivalent to an approx. 90-320mm lens."

Does this mean that its an actual 90-320 instead of 55-200 ? What does this statement mean ? If I zoom it all the way, will I get the same magnification as it would with a Canon EF 75-300mm f/4-5.6 III lens ?

Would I get more closer to the subject with the 75-300 lens ?


Thanks for any help :)

[rent]

this is due to the smaller sensor size in the XT/10D/20D models. the sensor size is 1.6x smaller than a full frame 35mm sensor, therefore it crops the field of view 1.6 times thus giving the same effect as a longer focal lenth.

a 70-300mm lens would have the equivalent focal length of 112-480mm on your XT. in fact, putting any canon EF lens on your camera would give you a 1.6x of its focal length.

-alex

[willg]

thats a nice shot at full zoom and wide open...as far as the crop factor goes...if you put a 300mm lens on a film body and a 200mm lens on a rebel you have more reach with the rebel because of the crop factor mentioned above

[zakmckracken]

What's the point for Canon to say that only for the 55-200 lens ? How come it didnt say the same thing for the 75-300 , the "when used on a Digital Rebel" parameters ?

This is a bit misleading for a newbie (like me)..

I thought that the 55-200 is the "rebel" parameters and in fact has the same range as the 75-300, or even better (320 at far end)

Thanks :)

[Andy_T]

Basically it's for people who move over from film and would like to have a lens with a similar focal length they had on film. It might also mean that the lens was recently designed with digital cameras in mind.

With ultra-wide third-party lenses like the last 12-24 lenses, it is not advisable at all to mount them on film bodies, because there would be heavy vignetting on the wide end.

Sigma also claims to use special coatings for their 'digital lenses' that are optimized for the sensor's higher reflectivity.

Best regards,
Andy