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Harley Goldman
5-Jun-2004, 08:48
Comparing the image circles of the 150mm APO-Sironar-S (231 degrees) and the Nikkor W (210), is the difference significant? I shoot landscape and primarily use tilt and rise. I have the Nikkor and have just occasionally run out of room on tilts and rises. Do you think it would be much of an improvement to get the other lens? There is definitely a cost to change and I am trying to determine if the higher price would buy me much. I am very happy with the image quality of the Nikkor, so it all comes down the extra room.

Ralph Barker
5-Jun-2004, 09:34
Assuming that Rodenstock and Nikon use the same criteria for determining their published image circle data (not actually a safe assumption), you'd get about 20mm (not degrees) of extra image circle with the 150mm APO-Sironar-S - or, about 10mm at top and bottom. Personally, I don't think that is significant enough to warrant the expense of the lens change. But, if 10mm of additional rise would solve those situations in which you've run out of image circle with your Nikkor, then it might be worth it to you.

Ron Bose
5-Jun-2004, 09:35
The 150mm Sironar-S is a sweet lens, one of Kerry Thalmann's future classics. I have a 210mm Sironar-S and like it a lot, but I've never used a Nikkor LF lens.

Having said that, I have a 150mm Sironar-N and have used it twice, between the 110mm SS XL and the 210mm Sironar-S it doesn't get a look in ... My point is, if you have plans for second or third lens and it may make the 150mm redundant, then there's no point in upgrading it.

Cheers ...

Steve Hamley
5-Jun-2004, 09:56
Harley,

I don't think anyone can tell you how much an extra 21 mm is worth! It all depends on how much that occasionally missed or compromised composition means to you.

Steve

Gem Singer
5-Jun-2004, 11:08
Hi Harley,

Stay with the Nikkor (I assume that the one you already have is the 150 f5.6 W), and add a Nikkor 90 f8 SW to your lens collection. It will give you 235mm of image circle to work with. The monetary investment will be less than upgrading to an Apo Sironar-S, and you will then have two great lenses to work with. Look at the Midwest website (www.mpex.com) for excellent selection and prices on previously owned lenses.

Ken Lee
5-Jun-2004, 12:33
"Assuming that Rodenstock and Nikon use the same criteria for determining their published image circle data (not actually a safe assumption)..."



This is an important point: There is often a substantial difference between coverage and useable coverage. Eric Wagner has done some excellent testing on this subject, and was kind enough to mail me some prints which show the images you get at the far reaches of coverage. Not all lenses are useable at their published or claimed extremes. Perhaps Eric will share some of this work in an article soon.

ronald moravec
5-Jun-2004, 18:55
Draw a rectangle with good tools 4x5. Connect the opposite corners to find the center. Then draw circles using the center as a midpoint and half the coverage in mm as the radius of the circle. You can see how far the rectangle can be moved and still be within the circle.

All the above applies as to advertising hype and different mfgr`s tolerances.

Spencer Cliss
6-Jun-2004, 18:50
If you buy another lens, look into the APO Sironar-W (not S, not N). 80 degrees, 252 mm image circle at a resonable size. This lens is sought after, not in current production and somewhat rare.