Super Telephoto These lenses are the battleships in any nature photographer's fleet. They are relatively heavy and ackward to use/employ. Large, substantial tripods are absolute must haves when using these lenses. Further, there's a whole technique to using these things affectionally known as "long lens technique". Simply meaning, every skill you ever gained shooting with a 200 or 300mm lens does not prepare you for the perfect technique required when working one of these beasts out in the field. Why does anyone suffer through these hurdles? It's all about the results, man. Without these super telephotos, close intimate views into the natural world would be lost. If you're into frame filling images of even the most cooperative wild subjects, one of these lenses will be a must. Add the issue of shooting a totally non-cooperative subject, now you're past the need. Yes, despite the overwhelming prescence of such beasts, super-telephotos are a bread and butter tool for any nature photographer.

• 500mm f/4.0 AF-S - This was my first long lens and even after the acquisition of a 600mm, this lens still fills a void. I think you'll find more and more photographers turning to 500's over 600's due to extraordinary size of the 600 compared to simply the large size of the 500. While the 500 may be large, the 600 is a behemeth meaning it's harder to move around and transport. While this isn't a big deal for those of reasonable health and condition working near their cars. It's a huge problem if you want to do any work out in the field. The 500 definitely has a place for those needing portability and that's how I use mine. Back in the "day", when this was my only long lens--I didn't even have the 300mm, I used this all the time. It performed in almost every respect except in one way. I couldn't to save my life make consistently sharp images with this lens and a TC-20e. Maybe, one out of ten was sharp enough to be acceptable. I've never been able to figure that one out. Whether aperture or shutter speed, I've never been able to figure out why this lens performed so poorly with the TC-20e. On the other hand, I almost always have the TC-14e on giving a 700mm f/5.6 equivilant capability, allowing really close explorations of just about anything. Unless I neet the extra stop of aperture, I hardly ever use the lens without TC-14e. Now that I have a 600, what do I do with the 500? Good question. I don't walk around that much when shooting hence causing the 500's recent inactivity. Still, no amount of optical performance will let you overcome the many travel restrictions on airlines. I have never flown anywhere with my 600. I think it's too large for my travel style. I only pack the 500 and deal with the slightly shorter focal length at the destination. Obviously, leaving the 600 behind to use the 500 isn't much of a concession and it's clearly better than leaving all my super-tele capability at home. The best part is the exact same long lens techniques honed using the 600 can be used with the 500. Being good at using the 600 only makes the 500 a piece of cake. What else can I say other than it's a pleasure to use, super sharp, easy to move around, makes incredible images, easily handled by even the most deminunative of our brethern on an adequate tripod system. Overall, the 500mm f/4 AF-S is a great super-tele bridging the gap between our longest 600mm's and the much easier to use 300mm lenses.while producing superior images. Highly recommended for those not placing small bird photography at the top of their subject lists and needing to move around a bit while out in the field.

• 600mmf/4.0 AF-S - The Dreadnaught of my fleet. By far the largest of my lenses, it weighs in at over 11 lbs making it about 50% heavier than my 500mm f/4.0 AF-S. The 600 mounted on my Gitzo 410, Wimberly Head, flash, and Nikon D2h tips the scales at almost 30 lbs. That's heavy for anybody to carry around their car let alone trying to hike with it. I have done some hiking with it but upon retrospect I could've used the 500 without losing any images. The real difference between the lenses becomes when working static locations. That extra 100mm's increases subject size by about 40%. Even though the focal length size is only 20% different, there's a multiplying affect thus really increasing the size of the subject with the longer lens. I guess you could say, big lens, big subject. As a rule, if I work out the truck, I pack the 600. I see no difference in auto-focus speed between the two lenses. There might be a slight nod to the responsiveness of the 500 when shooting in-flight birds being that there's less mass to move around but on the other hand, I think it's easier to shoot low light images since there's so much mass to move around and therefore minimizing vibrations due to camera shake. Unlike with the 500, I do not "weld" the TC-14e to the 600. I find the 600mm focal length is still useful in it's own right. So, I think you'll find me at least shooting as often with the TC-14e as without. Now, there are special handling issues with this lens. Since it's so unwieldy, you have to take great pains to be careful when moving this lens. It's weight can easily overcome the strongest of our numbers. I always use two hands when carrying the lens. If the lens isn't in its carrying case, it's on the tripod. If not on the tripod, it's in its carrying case. I never try to juggle the lens with anyting other things in my arms. The potential result of a "free-fall" experiment is too great to be other than very consertative when moving this lens around. I breath a huge sign of relief whenever I successful mount the lens before a full day shooting session. Oh, one other thing, I never leave the lens unattended. For the whole idea of keeping "things" from happening, I stand around the lens all the time. If I have to move to another location, the lens and tripod setup move with me even if I'm not using the lens at the time. Once again, this is for preservations reasons. So far, this practice has prevented a couple of unintentional catastrophe's from happening--knock on wood.