Coverage of the Nikkor T ED 360mm, 500mm and 720mm lenses

[Vaughan Bromfield]

Hello

I recently took the plunge into 8x10, and wanted to play around with longer focal length lenses. Nikon made two sets of large format telephoto lenses, the 360/500/720mm set which is rated to cover 5x7, and the 600/800/1200 which is rated to cover 8x10. Practical reports and reviews indicate the 1200mm lens is superb but requires significant dedication and technique to overcome camera vibration issues, not to mention its significant size, weight and cost. Reports and reviews also indicated that the 720mm configuration of the 360/500/720 set covers 8x10 and is significantly smaller, lighter and cheaper.

I decided to find out for myself, my rationale being that I have 4x5 and 5x7 cameras and the lenses can always be used on those.

Made with a Toyo Field 810MII using Shanghai GP3 100 film, developed in replenished ID-11 using continuous agitation 10 minutes at 20˚C. These were my first three photographs using the lenses and they were made from the walkway of a road bridge, so overall image quality (focus, sharpness etc) may not be optimal due to deficiency in my technique and vibration from traffic – particularly the 720mm lens.

Exposure times were 1/4, 1/2 and 1 second (the light was fading so I gave the last image with the 720mm an extra second). The 360mm and 500mm images were made with the lens closed 2 stops from wide open, while the 720mm was only closed one stop, so coverage may be even better with the lens closed further.

Nikon's specifications for image circle are 210mm (5x7) for all three lens configurations. My results indicate the 360mm covers about 230mm which a bit more than the specified 210mm, the 500mm covers about 280mm which is good for whole plate 6½x8½, while 720mm lens fully covers 8x10, with the limits of the circle well outside the 8x10 film area even with the lens closed just one stop.

If you're looking for a long focal length lens for 8x10 the Nikkor T ED 720mm is a good choice.


Nikkor T ED 360mm f8 lens


Nikkor T ED 500mm f11 lens


Nikkor T ED 720mm f16 lens

 

[Steve Goldstein]

Another plus is that the 720mm Nikkor-T at 780 grams is considerably lighter than either the 600mm or 800mm (1650 and 1600 grams, respectively, all weights from the 1994 Nikon LF lens brochure). Not to mention that the front cell of the 360/500/720 takes 67mm filters, whereas the front cell of the 600/800/1200 requires 95mm filters. If you truly need 800mm or 1200mm on your 8x10 you've got no choice, but if you can live with 720mm then as Vaughan points out that is indeed a very attractive option.

 

[ic-racer]

Very nice, I have always wondered about those lenses.

 

[Vaughan Bromfield]

My end-of-year gift to myself was a cheap-and-scruffy Toyo Field 45A as a project camera for bellows replacement and general cleanup. That camera is now the focus of my attention so I'm back on 4x5 for a while. The Nikkor T ED 360mm lens works well on the Toyo Field 45A with a flat lens board: the rear needs to be fully extended and the lens moved to the end of front standard but there is still a lot of travel left for close focus. The 45A doesn't have enough extension to focus the 500mm lens at infinity with a flat lens board but it can with the Nikon 100mm extension board that the kit came with. The 720mm requires even more extension and cannot be used with the Toyo Field 45A. (Toyo made a 100mm extension back for the 45A but even that may not be enough.)

On a Rittreck View 5x7 with either the 4x5 or 5x7 back the 500mm lens on the flat board will focus on infinity with 20-30mm of extension left for close focus; the 500mm lens covers 6½x8½ inch and the back adds another 50mm or so of extension which might get head-and-shoulder portrait close focusing. Even with the extended lens board the 720mm lens cannot focus on infinity with the 4x5 and 5x7 backs, but will focus on infinity with both the extended lens board and the whole plate back with about 40mm of extension left for close focus.

Lastly, the 720mm lens can be used on the Toyo Field 810M comfortably on the flat lens board, though it's getting close to full extension. If I really, really needed to use the 720mm on 4x5 I'd be getting the 4x5 reducing back for the 810M, or using a 4x5 monorail. However with the cost of the back being what it is, it would be cheaper to use 8x10 film and crop the image to 4x5.

Below are two images made with the 360mm lens on the Toyo Field 45A. In both instances I shifted/tilted the lens and caused vignetting: int he photo of the bridge I swung the back and front fully and shifted the front standard and probably ran out of image; in the phot of the seats I tilted the lens to place depth of field over the entire scene and encountered mechanical vignetting from the telephoto lens design (the front optical node is well forward and outside the lens barrel). All are made on Fomapan 400 developed in replenished ID-11 using continuous agitation. The bridge image shows some uneven development in the sky, I'm not sure why.