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View Full Version : 35mm Equivalent of 120mm Nikkor SW?



tgtaylor
15-Apr-2011, 09:20
The comparison chart on the Home Page says it's 17mm. Applying the dimensional analysis that I learned in college:

50mm (35)/300mm (8x10) * 120mm (8x10) = 20mm 35mm Equiv.

Also the chart says that the Nikkor will not support a front rise. However this image taken last week was shot using front rise and a back tilt:

http://www.largeformatphotography.info/forum/attachment.php?attachmentid=54006&d=1302370793

The above is a scan done with an Epson 3200 which will not cover the negative. But note that there is no fallout on the edges.

Thomas

Dan Fromm
15-Apr-2011, 09:25
But normal for 35 mm is 43 mm, not the 50 mm you plugged into y'r formula.

tgtaylor
15-Apr-2011, 09:43
Yep, using 43mm instead of 50mm would explain it.

I never had a 17mm 35mm lens and always thought that it was a fish-eye lens. Pentax has a 35mm lens (17mm 35 equiv) for the 6x7 which is a fish eye. But as you can see from the scan, there is no fish eye distortion on the 8x10 that you would expect using that focal length.

Thomas

Bob McCarthy
15-Apr-2011, 09:47
The Nikon has a huge image circle for a 120mm. The comment was likely meant for those who use it on 8x10 where the image barely fits. Barely means to get infinity in, its best to focus in a little and cover with stops. Focus closer (move lens away from focal plane) and you get more usable (larger)image circle to make movements.

bob

Mike Anderson
15-Apr-2011, 10:22
Yep, using 43mm instead of 50mm would explain it.

I never had a 17mm 35mm lens and always thought that it was a fish-eye lens. Pentax has a 35mm lens (17mm 35 equiv) for the 6x7 which is a fish eye. But as you can see from the scan, there is no fish eye distortion on the 8x10 that you would expect using that focal length.

Thomas

Nikon made a 13mm (for 35mm) that's not a fisheye:

http://www.mir.com.my/rb/photography/companies/nikon/nikkoresources/ultrawides/13mm.htm
http://www.kenrockwell.com/nikon/images1/13mm/distortion/D3R_1156-1200.jpg

...Mike

Ed Richards
15-Apr-2011, 13:15
I routinely use a rectilinear 12mm on 35mm:

http://www.epr-art.com/galleries/c3/