Most portrait lenses are wide enough to work with in a room and long enough to provide distance from the subject. Too much wide angle gives distortion to the facial features (bigger noses) and max depth of field. Too much telephoto compresses the face and may not have enough depth of field. The most common focal lengths for film indoor portrait work was between 75 and 120mm. You would also want one with an aperature of f/1.4, f/1.8, or f/2.8 to narrow the depth of field for portrait work, yet not have distortions or compession.
The choice of lens focal length is dependent on the type of camera. Do you have a full-frame or APS-C sensor in the camera? If you have the more common APS-c sensor, then you need to multiply the lens focal length by a factor (usually 1.5) to get the final focal length of the camera and lens you are using. If you have the more expensive professional full-frame sensor camera, then the focal length of the lens does not need any correction factor.
As an example: Your 100mm macro lens on an APS-C sensor camera is really a 150mm lens in focal distance (100mm X 1.5 = 150mm). If you are looking for a portratit lens in the normal range as stated above, you would look for something between a 50mm (50 X 1.5 = 75mm) and an 80mm (80mm X 1.5 = 120mm).
If you have a full frame sensor, then just look for a lens between 75mm and 120mm.
BeakerBob - Past MMMC Club President, current Board Member
yeah the inverted equation of depth of field read about that somewhere anyway yeah I have the 7d and the full frame 5dmkII was thinking about the 85mmL you try that yet?
well bob thanks for getting me in trouble with the wife over yet another lens as she says I said at least it isn't another vortech and she said yeah that would have been cheaper lol..but I have the green light just need to consider it since the other side of the argument is rental and it does make A sense but I know I will like it and not want to send it back decisions decisions hey you 2 want to go in on it? Maybe we each buy a lens and trade off every other month I like the new Canon EF 70-200mm f/2.8L II IS USM Telephoto Zoom Lens for Canon SLR Cameras and one more lens and we have a club how about it? I just got the 24-105L and it rocks . I will get the 85 if one of you guys gets the 70-200. Or this one Canon EF 16-35mm f/2.8L II USM Ultra Wide Angle Zoom Lens
Roger
Last edited by ROGERWILCO357; 04-30-2011 at 11:05 PM.
Reason: lenses