Schneider APO Tele Xenar 600/800mm Convertible

I’ve been getting superb results with this latest generation 8x10 telephoto lens, yet it's prompted little discussion in this forum, presumably due to its niche market and high price. This is unfortunate, since I believe it provides the highest resolution and contrast of any 8x10 long lens available today; it is noticeably superior to the Nikkor T 600/800/1200mm convertible and even the popular Fuji 600C. So in the spirit of “giving back” to all the wonderful folks here at the LF forum whose advice has helped me tremendously, I have written up my experiences with the Schneider convertible over the last six months, along with comparisons to the Nikkor and Fuji.

I have no affiliation of any type with Schneider, Nikon, Fuji or any other LF manufacturer or reseller.

Background

When I added an 8x10 camera to my LF arsenal last year, I initially purchased a mint condition Nikkor T convertible (with 800 and 1200mm rear elements) to supplement my Fuji 600C for long-lens shooting requirements. My shooting style includes photographs of distant objects fairly often, and most available reviews of the Nikkor generally concluded that it was a “good” lens at 800mm and “acceptable” at 1200mm. As I gained experience with the Nikkor, I realized that if I were a contact printer or made only moderately sized B&W enlargements, this assessment would seem entirely accurate and there would be nothing more to say.

But for the particular work I do (enlarged prints of 30x40 inches and larger, over half of which are in color), I found it difficult to achieve consistently satisfactory results with the Nikkor T. Nikon does not publish MTF charts for its LF lenses, but for a modern multi-coated lens the T convertible clearly provides less acutance and color saturation than my other top-notch lenses, and for my taste requires pre and post exposure correction to achieve satisfactory results. In particular, I found it necessary to push and slightly underexpose my color chrome film to coax as much acutance and color saturation out of the lens as possible, then to apply aggressive sharpening afterwards (or a higher contrast setting when printing to B&W paper) to achieve a satisfactory print. Also, rigorous stabilization, particularly when using the 1200mm focal length (multiple tripods or stabilizing arms: one for each standard, plus one for the camera body), was needed to have any shot at sharp photographs in the field. These requirements detracted from the utility of the lens: pushing chrome film is not desirable for high contrast subjects; lugging multiple tripods on hikes was out of the question (at least for me!); and even with multiple tripods a slight breeze easily destabilized the 1200mm configuration. So reluctantly I began looking for a better solution.

Schneider had previously sold a high-end dedicated 800mm Tele Xenar HM that was huge and prohibitively expensive, but roughly five years ago replaced it with the smaller, more moderately priced APO Tele Xenar 600/800mm convertible. Schneider publishes MTF charts for all of its lenses, and the Tele Xenar convertible charts showed performance quite similar to its shorter focal length cousins such as the APO Symmar-L. This seemed promising, and based on this information as well as conversations with several folks, I decided to take the plunge and purchased an 800mm APO Tele Xenar, with the intent of purchasing the 600mm rear element if the lens performed well. My presumption was that the Schneider 800mm would outperform the Nikkor 800mm, and likely yield comparable results when cropped versus the Nikkor 1200mm. I could therefore achieve my objectives with the added convenience of reducing my longest focal lengths from two to one. I received the Schneider lens within a couple weeks, and began comparison testing versus my Nikkor.

Comparison with the Nikkor T 800/1200mm

As expected, at the 800mm focal length the Schneider was clearly superior to the Nikkor T 800. Contrast and color saturation was top notch (no more pushing!), and resolution was superior at the corners and even at the center of the image circle. The Schneider holds up well even at relatively open apertures (I could focus at f/12 and get extremely sharp results at f/16, whereas I typically shot the Nikkor at f/22), giving the option of using a faster shutter speed (always good when trying to stabilize a long lens!) when photographing distant objects. The Schneider does require a bit more bellows extension (461mm versus 409mm at infinity focus), but I did not find this difference to be significant.

Comparing the 800mm Schneider with the 1200mm Nikkor is a bit more complicated. The Schneider provides a brighter, higher contrast image in the ground glass and is easier to focus. As actual results go, the Schneider has higher contrast and color saturation, and frequently provides greater detail than the Nikkor despite the shorter focal length. Occasionally, though, I have encountered cases where if everything sets up perfectly for the Nikkor (scene contrast permits a one stop push, virtually no breeze, etc.), the Nikkor may resolve some features slightly better than the Schneider, even though the overall image superficially appears softer. On balance the Schneider produces sharper results more often than not, but the big factor tipping the scales in favor of the Schneider for my usage is that it provides more successful results. The Schneider does not require pushing film; does not require multiple tripods (I usually can get by using one tripod plus a long lens support arm); is more robust in the wind (less bellows extension than the Nikkor 1200mm); and can be shot nearly wide open (the Schneider is extremely sharp at f/16, enabling a fast shutter speed on a sunny day; whereas I typically shot the Nikkor at f/22). In the field I am getting over a 90% image success rate (I must admit the wind still blurs shots on occasion) with the 800mm Schneider. I was only getting about a 50% success rate with the 1200mm Nikkor.

Comparison with the Fuji 600C

I have long suspected that my Fuji C lenses, while quite good, could be a bit sharper when shot at or near infinity, and this was partially confirmed when I purchased the APO Tele Xenar 600mm rear element. Photographs taken with Schneider when viewed under a 3x loupe had more “snap” than those taken with my Fuji 600C, and when viewed under a 10x loupe it was easy to see why: the Schneider clearly provided higher resolution and contrast. Focusing the f/9 Schneider is a bit easier versus the f/11.5 Fuji, plus it is easier to stabilize in the wind (the Schneider requires only 461mm of extension for infinity focus, versus 573mm for the Fuji). As I typically take only short hikes with my 8x10 kit, the Schneider has mostly displaced the smaller Fuji as my 600mm lens.

Close Focusing and Extension Requirements

At the request of one of our forum members, I determined that the 800mm Schneider can focus on a target about 15 meters away using a bellows extension of about 25 5/8 inches (652 mm). Since Schneider has told me that the APO Tele Xenar is optimized for subject distances of 18m or greater, it is possible to use this lens to full effect on 8x10 field cameras with moderate extension such as the Phillips 8x10 Compact II (26 inches maximum extension). However, the sheer bulk of the lens requires a fairly large lens board (a 4x5 Linhof Technika lens board will not work), and the extension it requires (628mm flange focal distance for the 800mm focal length) prevents its use on typical 4x5 and 5x7 field cameras.

Image Circle and ULF Applications

The APO Tele Xenar does not mechanically vignette for quite a ways beyond its rated image circle (400mm IC for the 600mm focal length, 480mm IC for the 800mm focal length), so the lens will cover some or most of the ULF camera formats. Alas, I do not own any ULF platform, so someone else will have to determine which ULF formats this lens can cover. Sorry!

Cost

For a long time I considered the APO Tele Xenar an enormously expensive luxury item, but as one accumulates an 8x10 field kit its value comes more into perspective. The Nikkor T 800/1200 is still an excellent lens combination for many applications, and I ultimately sold mine on Ebay for about $2,800 USD. I purchased my new 800mm APO Tele Xenar for about $3,300, for an upgrade cost of $500. Not cheap, but not exorbitantly expensive either, considering you have the convenience of replacing two focal lengths with just one (plus the Schneider comes with a really nice carrying case). If one replaces a Fuji 600C ($1,150 most recent used sale price on Ebay, as of this writing) with the 600mm Schneider rear element ($795 new price), then the upgrade cost is down to $145. Granted, the Fuji is far lighter and has greater coverage, but if you don’t do much hiking with long lenses or need big ULF coverage (I don’t), then upgrading to a sharper, more easily stabilized lens can be an attractive option.

Conclusion

Excluding possibly the Schneider XXL fine art lenses, the APO Tele Xenar convertible is clearly best of class among modern current LF long lenses. Alas, this lens is far too bulky and requires too much extension to be used on 4x5 or 5x7 field cameras, so if one desires maximum long lens optical quality then an 8x10 or similar camera platform will be needed.

If you make contact prints or moderately sized B&W enlargements (say 16x20 inches or smaller), then the performance differences mentioned above probably won’t make much difference, and the Nikkor T may be a better solution. But if you make large enlargements, shoot color, or just need the highest contrast negatives possible, then the APO Tele Xenar will provide noticeably more snap to your images and more consistent results in the field. I’ve been extremely happy with mine!

Thanks Eric,

I've been thinking about an 800 myself, but I shoot a lot of 4x5, some 8x10, and soon to be 8x20, and I haven't been able to justify the cost for an 8x10-only lens.

BTW, that 550mm Schneider Fine Art appears to be .... a Dagor.

Steve

Thanks for the review. If I can ever afford to go that way, (barrel & packard for me so far) I will be better able to make the choice in a single buy. Thanks, John

I haven't used any of these lenses but I've been thinking about a 600mm for some time so your observations are very useful so thank you for writing them up. However, just looking at paper I must say I am skeptical of your description. The APO-Tele-Xenar 800mm MTF I've seen is FAR behind the APO-Symmar-L (which is superb) and it produces a good bit of distortion as well which may or may not matter depending on your application. The MTF curves would suggest that it shouldn't even hold up at infinity to a good process lens like a Ronar in terms of resolution so its hard to believe that it can out-resolve the Fuji. You claim that the tele outdoes the Fuji in terms of contrast and resolution but often for high quality optics there is a trade-off when a lens appears contrastier than another because the high frequencies have a poor response. In other words more high frequency detail = less apparent contrast at lower frequencies. This is what the MTF for the Schneider would really seem to imply.

I guess the question I have is if you are certain that you really resolve more detail with the telephoto than the Fuji-C because if so one would really need to question the quality of the Fuji which is the lens I've most seriously been considering myself.

Edwin,

I'm a landscaper so distortion in a telephoto lens doesn't bother me. Of course YMMV.

The MTF charts for the APO Tele Xenar convertible can be found here:

www.schneiderkreuznach.com/foto_e/txr_apo/txr_apo.htm

I was looking at the MTF charts of the 300mm APO Symmar-L (which has a similar rated image circle to the 600mm APO Tele Xenar) and also the 360mm APO Symmar (which I own) when I did my spot comparison with the APO Tele Xenar charts. To my admittedly amateur eye, the APO Tele Xenar (particularly the radial measurements) didn't look too bad in this comparison, although I'm sure you know far more about MTF charts than I do so I defer to your judgment.

Regarding the comparison to the Fuji C, it could well be that part of what I am seeing is the result of sample variation and manufacturer quality control. I have had one LF reseller here in the U.S. tell me that he does not stock Fuji because their quality control is inferior to Schneider, Rodenstock et al. Of course other resellers and many owners swear by their Fuji's, so there is hardly any consensus on this point. However, given the relatively price disparity between the Fuji and Schneider, one would hope that part of the Schneider's price premium includes superior manufacturing quality control. I have owned only one Fuji 600C, so I have not tested for any unit variation. I have owned or rented two Nikkor T's, and they both performed similarly, so I feel that its observed performance is most likely a function of its design.

Has any compared the nikkor T1200 to the schneider 1100mm fine art XXL?

Eric,

Since you mention that you were looking at the 300mm Symmar MTF curves I can understand our different impressions. I was looking at the 480mm thinking that it has the closest focal length. Understand that when you use the 300mm for comparison with the 600mm telephoto because they have similar image circles you end up comparing very different angular coverage. Assuming the MTFs are very similar, what they are telling you is that the Symmar performs similarly to the telephoto at twice the angular distance from the center. Another way of looking at it which i think would give an sense of the individual lens formula characteristics would be to compare the portion of the MTF curves needed to cover 8x10 with the 600m tele to the portion needed to cover 4x5 with the 300mm symmar. Then you're comparing equivalent angular coverage which seems dimensionally logical.

For what it's worth, I don't think there is a whole lot to understand about MTF graphs once you understand what they mean and figure out all of the associated parameters on the charts. The difficulty is getting a sense of how a particular curve influences the visual character of an image. I am not an expert by a long shot but I can relate a similar experience from the 35mm world. I've used several different 50mm Pentax lenses and they are all very decent. some years ago Pentax released a really fancy 43mm lens with all sorts praise and great reviews. I have one and it makes those images that just jump out at you with incredible contrast and a particularly 3D look. I absolutely love it. I was surprised later on when I found that tests consistently show it to have lower resolution than any of the much older 50mm lenses. It's only been recently that I've come to understand that this is not at all puzzling but actually makes complete sense.

I think one could argue that for certain large formats, with their relatively small reproduction ratios, lower high frequency response can be beneficial if one values a contrasty image.