I just bought a Fujinon W 250mm 6.7 to use on 8x10. When trying the lens, I noti ced that the coverage did not seem as great as I expected. If I use maximum rise and a bit of tilt on my Wisner 8x10 Traditional, I hit the limits of the image circle. Can I be sure that this lens is the one with 398mm of image circle. It i s in a Copal shutter with a silver shutter-speed ring.
I compared the Fujinon 240 A to my new Fujinon W 250 f6.7. The image circle cuts off at the same place with both lens wide open. The 250mm f6.7 does not appear to have any more coverage than the 240mm A.Can this be right? Have I bought the 250mm f6.7 for nothing?
William,
The 250 should have about 60mm of rise with landscape format and 50mm of rise in portrait format (at f/22) (or conversely, 50mm of shift in landscape, and 60mm shift in portrait). You should be able to set the camera up straight on, and then shift the standards or use rise/fall to give you enough displacement to see the 50 or 60mm. 50mm is approx. 2", so shift the FS > 2" and see where the circle falls. If at 2", the corner is just starting to show, then I suspect you have the right coverage.
Don't forget to stop the lens down for the test.
---Michael
Michael, I just did the test you described and the Fujinon 250mm f6.7 has the coverage you said it should. I also did the test with my Fujinon 240mm A, and the image circle cuts off in the same place as the Fujinon 250mm f6.7. Could the 240mm A have more coverage than the 70 degrees it is said to have? I feel I have gained nothing in switching from the 240mm A to the 250mm f6.7.
I believe the rise posted above is just reversed -- 50mm for portrait and 60mm for landscape. For an 8x10 ratio (i.e. 0.8), one should be able to achieve more rise in landscape than in portrait mode. I come up with the same values, but reversed orientation.
Aaarg. I take it back. I misread the shift for the rise, versus the portrait for the landscape.
If you need more movement, try a 10" Wide-Field Ektar. 422mm circle, single coated and designed for color, reasonably priced around $500, and sharp. Potential downsides: kind of big and heavy for backpacking, Ilex shutter may or may not be accurate enough for your needs.
William,
I don't know how the 240 A performs. It's possible it has more coverage than the literature states, but I doubt it, since coverage is the magic word in LF lenses. I don't have a 240A and was considering bidding on yours on Ebay, but decided that I am going to search out an old SC W 210 for my use.
One thing, is your 250 an SC lens? They appear to have cut the coverage of all their W series lenses in the redesign, and they also went to MC glass at that point.
Yes, I think the 250 is SC, but that is okay. I bought it from an individual who bought it from a dealer. The dealer told him it was MC. When the person I bought it from said it was MC, I was skeptical. I am not surprised to find out is it SC. What is interesting is that the 240 A seems to have an 80 degree FOV rather than the listed 70 degrees. I focused the 240A at infinity and used the maximum front fall my Wisner Traditional allows, which is 4 3/8 inch (according to Wisner's specs.) With the back in vertical position, there was about 1/4 inch darkening in the corners. When I put my 250 on and changed nothing, the darkening in the corners was the same. If I focused my 250 to infinity, then the corners were just barely starting to darken. From my comparison, I think the 240 has much more coverage than stated. People on this discussion page implied that I was crazy to use the 240A for architecture, but most shots came out fine. Only when I used much rise and tilt together did I get corner darkening.
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