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Darcy Cote
25-Nov-2009, 23:31
Hi:
I am building a 6x32cm camera and I would like to use this lens on it. What I have read is that you can use it on 8x10 with no movements 312mm at f22. That would work but what I would like to know, if I have the lens wide open at f8, what would the image circle be? Would it work for me as I would like to use this thing hand held at times.

thanks for the replies.

Darcy

venchka
25-Nov-2009, 23:40
Non-expert answer: The image circle is the same. Not as sharp corner to corner wide open.

I wonder if I am correct?

seabird
26-Nov-2009, 04:00
For the SW-120 f8 Nikon's own specifications (from their brochures) indicate an image circle of 200mm @ f8 and 235mm @ f32. See: http://members.iinet.net.au/~cbird/index.html and click om the Nikkor LF lenses link on the LH side.

At least one correspondent has reported to me that the image circle is 312mm @ f32. This is significantly greater than Nikon's specification. I can only report what the Nikon brochure says - I do not own this lens and have no way of validating the manufacturer's specifications.

HTH

Doremus Scudder
26-Nov-2009, 05:17
My Nikkor large-format lens brochure lists a 312mm image circle for the SW120 at f.22 and a smaller 200mm image circle at f.8. (Seabird, maybe you read the circle for the SW90 (235mm) in the next column by mistake?)

Typically, large-format lenses wide open have unacceptable aberrations at the edges of the image circle at large apertures (hence the specs at f.22 normally, where the circle is at its optimum quality). The 200mm image circle given for f.8 does not mean that the circle of illumination is much smaller, but rather that the image quality outside of 200mm is not up to Nikon's standards. You can see what it delivers for you, but I would imagine it would be quite soft at the edges.

Best,

Doremus Scudder

Ed Richards
26-Nov-2009, 07:18
Use TMY-2 and Xtol 1-2 or 1-3, so you get at least 400 ASA. Then you use the camera outdoors. On a sunny day you could shoot f22 at 250 and do fine, and since you should be able to handhold down to 1/60, that would give you a lot of daylight options. Just skip the R29 filters.:-)

seabird
27-Nov-2009, 03:53
My Nikkor large-format lens brochure lists a 312mm image circle for the SW120 at f.22 and a smaller 200mm image circle at f.8. (Seabird, maybe you read the circle for the SW90 (235mm) in the next column by mistake?)


Further to Doremus' post I have checked my Nikkor brochures. Doremus is quite right. The brochures indicate a 312mm image circle @ f22 for the SW-120/8.

Apologies to all for the misinformation. I'll correct the specs on my website shortly.