Two months ago I bought a Leica R 21 mm F4, I tried it and I discovered that its vignetting was really heavy, I thought it was faulty so I gave it back. One month ago I bought another 21 mm in another shop but also this has the same problem, though a little bit less. Vignetting is visible at all aperture, the dark corner become more little stopping down but, however are always visible and, moreover, they are not equal in dimension. In a landscape with a blue sky taked at F11 you see in the high corners two little triangles Vivitar, paied then times less, that, as regard this problem, is much very darker. This is really annoying and, I think, unbearable for a lens of this price, also considering that I have a 19 mm F 3.8 better. Can someone tell me if I found two faulty exemplars or this is a tipicall caracteristic of this type of lens. Because in the first case I' ll give it back and I'll continue to look for a normal exemplar, as , apart this problem it is a really good lens.

-- Paolo Lombardi (pa.lom@tin.it), August 23, 2001

Answers

I own two 21/4-R S/A's, one from around 1970 and the other from around 1983, both in mint condition; and I previously owned another 1970-vintage 21/4. The kind of vignetting you describe sounds more like physical vignetting--the kind caused by a filter rim or too-deep lens shade. Optical vignetting, or light-falloff, is very, very slight with the 21/4 S/A and is gone completely by f/5.6. I can't explain why your results are different.

-- Jay (infinitydt@aol.com), August 23, 2001.

I have the 21mm f/3.4 (never used the f/4). It vignettes, but it's not nearly as severe. I couldn't describe the vignetted area as "triangles." There's just a gradual darkening of the sky from center to upper corners. Not unattractive, really. It adds drama. I think the difference between these two lenses is just a matter of some refinement, not like day and night. So I'm inclined to think along with Jay that something might be cutting off the image. But I might also mention that this lens seems to have a lower transmission factor than most lenses, per rated f-stop. You might try opening up about 1/3 to 1/2 stop from your meter reading to see how that might affect your results.

-- Bob Fleischman (RFXMAIL@prodigy.net), August 23, 2001.

I think something may be amiss with your camera body/lens mount. My 21/4 shows what should be the typical vignetting and is not very obtrusive at that.

-- Dave Doyle (soilsouth@home.com), August 23, 2001.

I second everyone else. Mine has no worrying vignetting - did you have a thick filter on it by any chance? That could do it. I use no filter on mine.

-- Robin Smith (smith_robin@hotmail.com), August 24, 2001.