dh003i
14-Oct-2008, 10:24
Looking at 4 lenses...
150/5.6 Rodenstock APO-Sironar S: $950
150/5.6 Schneider Symmar S: $400 +MC; $260 -MC
210/5.6 Rodenstock APO-Sironar S: $935
210/5.6 Schneider APO-Symmar: $400
Those are prices from eBay searches of either ended auctions or buy-it-now listings. Why are the Rodenstock's so much more expensive (literally arm, leg, and first-born, whereas the Schneider's are just arm and maybe leg ;-).
Looking at these resolution specifications (http://www.hevanet.com/cperez/testing.html), it isn't like the Rodenstocks have significantly better resolution; in fact, average resolution for them is worse, although they have more coverage in each case. Looking at the lens specs (I calculated average resolution from cnt, mdl, and edge resolution at all f-stops), I don't see why the Rodenstocks are that much more:
150/5.6 Rodenstock APO-Sironar S
Image circle: 231 mm
Tilt Degrees Landscape: 18.67
Minimum lpmm: 35
Maximum lpmm: 76
Average lpmm: 58
150/5.6 Schneider Symmar S
Image circle: 210 mm
Tilt Degrees Landscape: 14.28
Minimum lpmm: 38
Maximum lpmm: 85
Average lpmm: 60
210/5.6 Rodenstock APO-Sironar S
Image circle: 316 mm
Tilt Degrees Landscape: 25.05
Minimum lpmm: 43
Maximum lpmm: 55
Average lpmm: 76
210/5.6 Schneider APO-Symmar
Image circle: 305 mm
Tilt Degrees Landscape: 23.7
Minimum lpmm: 54
Maximum lpmm: 76
Average lpmm: 64
I used the Scheimpflug calculations to figure out the maximum tilt of image planes at different distances, given the maximum tilt of the lens (in landscape), and even as close as 1 foot, it's only a difference of 6.4 degrees (33.04 vs. 26.62) at 150 mm and 1.3 degrees (31.57 vs. 30.26) at 210 mm for the Rodenstock vs. Schneider lenses. So what's up?
The 150 mm lenses seem to have more falloff in resolution at the edge (reflected by their minimum resolutions) than the 210 mm lenses.
PS: The resolution tests for the 150/5.6 Schneider don't say whether it was the multi-coated version or not. Does that make a difference for resolution?
150/5.6 Rodenstock APO-Sironar S: $950
150/5.6 Schneider Symmar S: $400 +MC; $260 -MC
210/5.6 Rodenstock APO-Sironar S: $935
210/5.6 Schneider APO-Symmar: $400
Those are prices from eBay searches of either ended auctions or buy-it-now listings. Why are the Rodenstock's so much more expensive (literally arm, leg, and first-born, whereas the Schneider's are just arm and maybe leg ;-).
Looking at these resolution specifications (http://www.hevanet.com/cperez/testing.html), it isn't like the Rodenstocks have significantly better resolution; in fact, average resolution for them is worse, although they have more coverage in each case. Looking at the lens specs (I calculated average resolution from cnt, mdl, and edge resolution at all f-stops), I don't see why the Rodenstocks are that much more:
150/5.6 Rodenstock APO-Sironar S
Image circle: 231 mm
Tilt Degrees Landscape: 18.67
Minimum lpmm: 35
Maximum lpmm: 76
Average lpmm: 58
150/5.6 Schneider Symmar S
Image circle: 210 mm
Tilt Degrees Landscape: 14.28
Minimum lpmm: 38
Maximum lpmm: 85
Average lpmm: 60
210/5.6 Rodenstock APO-Sironar S
Image circle: 316 mm
Tilt Degrees Landscape: 25.05
Minimum lpmm: 43
Maximum lpmm: 55
Average lpmm: 76
210/5.6 Schneider APO-Symmar
Image circle: 305 mm
Tilt Degrees Landscape: 23.7
Minimum lpmm: 54
Maximum lpmm: 76
Average lpmm: 64
I used the Scheimpflug calculations to figure out the maximum tilt of image planes at different distances, given the maximum tilt of the lens (in landscape), and even as close as 1 foot, it's only a difference of 6.4 degrees (33.04 vs. 26.62) at 150 mm and 1.3 degrees (31.57 vs. 30.26) at 210 mm for the Rodenstock vs. Schneider lenses. So what's up?
The 150 mm lenses seem to have more falloff in resolution at the edge (reflected by their minimum resolutions) than the 210 mm lenses.
PS: The resolution tests for the 150/5.6 Schneider don't say whether it was the multi-coated version or not. Does that make a difference for resolution?