optical performance of EF lenses

greenspun.com : LUSENET : Canon EOS FAQ forum : One Thread

in what ways can i know the optical performance,eg.resolution,of a lens? Already some people in this forum had said that photodo is not reliable. thanks

-- legnum (legnum212@email.com), January 03, 2002

Answers

Why don't you try renting lenses that you are interested in? Larger stores like Calumet Photographic have rental departments and if they do not have a location near you they will ship it to you. Most times you have to take other's oppinions of lenses with a grain of salt. Photodo might be flawed but it is a good general guide. Lenses do have some variances and sometimes you will get a bad one. If you are looking for the perfect lens this might be kinda tough nothing is perfect however YOU should be satisfied with the result. A good test might be to purchase a lens and go to a local store ask to try out the same lens. Shoot a couple of pictures with each lens on the same roll. Compare at your maximum printing size. Also, though lens might have a high level of resolving power it might be beyond the capability of the film {though not likely} or beyond the actual printable resolution {very likely}.

Basics to remember.

People's advice or Photodo should not be taken as a truth. You need to test if you want to be absolute when looking for something very specific.

You usually can't go wrong with an L lens. You normally get what you pay for.

A lens has to work for you and work well within you shooting style. Example: a 35mm 1.4L might give the most resolving power of any lens in the world but if you need to crop a 20X24 image size to make an 8X10 you have many other things to worry about: the limitations of the film, extreem enlargement, limitations of the printing lens, enlarger allignment, easel defects, and paper limitations.

Lenses may have manufacturing variances. Example: Leica M lenses have the actual focal length printed on the barrel by the mount. A 50mm might be anywhere from 48mm to 52mm.

Know the limits and purpose of 35mm. If you want to have great results with ease of use {purpose} it is a compromise you will only be able to print up to ?X? size (limits}. If you need to print larger or want better image quality, maybe move up medium or large format enlargement quality would be better but the ease of use can get to be unacceptable.

I know I'm going to get crucified for this. Most 35mm lenses have more resolving power than what is visible to your eye. It is actually a lens or image with more contrast that will appear sharper when viewing.

Hope this helps even though it is not specific.

-- john (mr.-n-mrs.g@att.net), January 04, 2002.


John banged the keyboard and spewed forth: I know I'm going to get crucified for this.

Consider yourself crucified.... :)

-- Colin Miller (miller.photos@att.net), January 05, 2002.


Moderation questions? read the FAQ