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In closing, thanks to all who shared useful information on commonly available lenses for 4x5 per my well-defined needs in the opening post.
As a side note, the interesting thing about my father, a highly decorated USAF combat and test pilot, is that he never bragged. Never mentioned that he had a single commendation. But then, that was the Greatest Generation.
PaulOUT
Yes - in small aircraft vibration and buffeting is by far the major factor. From a Cessna I've found it easy to pan to compensate for the general motion of the plane but only a high shutter speed, and/or a camera gyroscope will compensate for aircraft vibration and buffeting. (With smaller formats, image stabilization in-lens or in-body may be helpful in some circumstances.)Quote:
Originally Posted by Jim Michael
Bill
This is the lp/mm performance measured by Mr Perez of a M 200mm sampleQuote:
Originally Posted by pchaplo
f/11 68 76 38 (Center Mid Edge)
f/16 68 68 34
f/22 60 54 48
http://www.hevanet.com/cperez/testing.html
Still not a lab test but a practical one, and we have to remember that from one unit to another one there is a variability.
I have Kenyon gyro if needed.
Quote:
Originally Posted by Photomagica
Great site. I’m really enjoying his writings, images, and lens tests/comparisons. Thanks.
Quote:
Originally Posted by Pere Casals
Im re-reading all your most helpful notes. Very helpful info and greatly appreciated. The f/5.6 Nikon W’s were tested at f/8 by Danny another forum member here and he found that the specifically the 180mm (and Schneider’s APO-Symmar 180mm) were sharp for 4x5 at that ”one stop down” aperture.Quote:
Originally Posted by Oren Grad
The trouble is that the Copal 1 shutter limits my fastest shutter speed to 1/400 and in real life 1/3-1/2 stop slower than that.
Y'know, if you got a Speed Graphic you could have higher shutter speeds.
William Garnett...who took some really incredible aerials back in the day - often did so while piloting alone with his Graflex held over his shoulder. He'd worked out a routine which took advantage of his intimate feel for lighting, timing, placement, and...when he wasn't simply cutting the engine (which if I remember correctly he did not like doing)...those RPM ranges which presented the least amount of vibration. Amazing work!
...cannot mention William Garnett without paying homage to Bradford Washburn!
Just let me add that, being always insteresting, lens performance can be secondary to obtain good results. How photographer manages DOF, aperture, focusing, alignment, shake, film usage, and post-processing may be more important than ultimate lens lp/mm in the field. For example a film may deliver no more than 50lp/mm in regular low contrast situation, and only with a very contrasty pattern it can resolve more, so other limiting factors may make high lens performance secondary.Quote:
Originally Posted by pchaplo
Also the sharp look of a photograph may be more related to other factors than to resolving power.
I'm a big fan of measuring lp/mm, but I realize that it would be a secondary concept for a true artist. "Dovima with elephants" was made with a good lens, for sure, but this was a 1955 technology lens.
For aerial photography you have to consider if your motion blur/shake is to limit resolving power in practice, making useless optical performance beyond certain level. And optical performance also depends on aperture, and from aperture and film you have a shutter speed that is related to blur/shake. But smaller aperture also is related to "on film" DOF, that will ensure focus if not perfect alignment and flatness.
So, beyond lens performance you also have to make a good balance of the settings, and this may be more important than ultimate lp/mm measured in a lab.