Sigma 600mm f/8 (the gray/green one) I am perplexed about where to post this. This post is about a lens, not a camera. The lens is a perfectly ordinary lens, not an "alternative" home-built or some such. Moreover, it is from the classic era, and made to fit a classic manual camera, the pre-AI Nikons. I don't feel too "casual" about it, either. I am not actually shooting it on a Nikon, so I guess it wouldn't be too welcome there (although there have been posts on it http://www.photo.net/nikon-camera-forum/00LNU1). In fact, this lens was made with dedicated mounts for just about every major (classic, need I say) camera line. Here's the catch, up front, in terms of this forum. Although I have Nikon film cameras and even adapters for this lens to be used on other cameras closer to the classic manual form, I here am posting some pictures taken with the lens on a modern digital camera. I was more interested in getting a handle on the adequacy of the lens for a possible return and so went the ritualistically impure path. I really wanted to give it more of a workout than I could have done on my Nikon F or Nikkormat EL particularly with the additional complications of scanning negatives. Mea maxima culpa. If the assembled masses and the moderators find this to be too impure for this forum, please move it to wherever you think it might go better. Does it make any atonement that the comparison 'normal' shots were made on a Canonet QL 17? An earlier post about 500mm lenses of mine was here on the Classic Manual forum, besides. The lens itself is a Nikon mount, gray-green Sigma 600mm f/8 lens. I dropped into the local camera store on Fr?gedæg (also Fredag or Friday), and there it was, gently whispering to me. I had sort of promised myself that I would buy any more 500mm lenses (see my post at link, here on this forum). Shouldn't five of them be enough? Besides, I had got what seemed to be a really fine (IMHO) 500mm lens in the Reflex-Nikkor 500mm f/8, and the two Spiratones, especially the later one, were also decent lenses. So who could ask for anything more? No one would be so obsessed and goofy as to buy a sixth 500mm lens, would they? Except this lens threw me a curve, it was not a forbidden-fruit 500mm lens, it was 600mm! I know that it's not the size that counts. but wouldn't you or your loved one want another 100mm if you could get it? I have been unable to find out much about the lens. It is not black, but gray-green, as said. The actual lens looks much like the later(?) 600mm f/8 black lenses made by Sigma, and is about 110mm from mount to filter ring. Like most of these catadioptric lenses (link), it takes 30.5mm filters mounted at the rear of the lens. On this one, not screw-in, but in a drawer. In addition to the lens itself, there is a matching metal hood that adds about 60mm to the length of the ensemble. I have no front lens cap for this one. The diameter of the lens hood at the end is about 105mm, and the screw thread at the lens is something in the 92mm ± range. My "I Can't Believe It's Not Butter" lid that works fine for the Reflex Nikkor is much too small for this. (It's back to that well-equipped photographic supply emporium, Krogers, with the hood in hand, I think.) Aside from those who will object to the camera, we all know that there is a certain other cabal here who really react badly to mirror lenses. Perhaps their mother was frightened by one when they were in the womb, but they will chime in with a screed about the awful donut bokeh (perhaps their mother was frightened by a policeman with a mirror lens?). The lack of contrast of such lenses will also be alleged. If you belong to this group, this might be the point at which you want to begin composing your response in your mind. The pictures below will illustrate or not the lack of contrast in these shots. These are not manipulated except for size and conversion to sRGB through "Save for Web & Devices.." As with the Nikkor lens, this lens seems to be less susceptible to the donut-bokeh problem than some mirror lenses. It generally shows up on any of them most often when there are strong highlights in the out-of-focus areas. Sometimes there are other bokeh artifacts, particularly an occasional "spikey' effect in foliage. Aside from the 'out-of-focus' areas, focus seemed unusually clear on this lens to me. Things snapped right in and out of focus, and it was usually easy in a larger viewfinder to see where focus was. Even at distance, of course, these very long lenses tend to have very small depths of field. Honestly, and too bad, it is not as easy to get a sharp focus on a moving bird as a modern AF lens would be, but this is a problem shared by all of us who love and use our old "manual" equipment. If it's something that you can anticipate, of course you can prefocus, but a grab shot of a pelican landing is tougher, darn it. I was very surprised by the quality of the lens. While I have and use lots of old and new Sigma lenses, this one seems to be exceptionally fine. It's easily in the same league as the 500mm Reflex-Nikkor, and if I am totally honest, I have to say that I suspect it may actually be a little better. Anyhow, here is the lens. First, a view as seen by my victims, and secondly the lens and hood from the side mounted on some kind of camera that will probably be unrecognizable to the more white-robed of our membership.