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Old 14-03-2012, 09:36 AM
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gregbradley
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Join Date: Feb 2006
Location: Sydney
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Admitttedly Martin has posted 100% and that will show up the warts but here is one I took at 2x2 binning with a Proline 16803 (about 16 times more demanding of squareness than an 8300 chip due to its size)
and a cheap ($250 or so) Pentax 67 55mm at F5.6:

http://www.pbase.com/gregbradley/image/142065586


There is slight tilt on the right side but minor. At 1x1 binning though the coma is gross. At 2x2 magically it is pretty precise and with the 16803 chip it still shows plenty of resolution at 2x2.


Here is one (sorry its a small image) STL11 and Nikkor 50mm F1.8 which as I recall was sharp corner to corner no coma:

http://www.pbase.com/gregbradley/image/66496862

I know you aren't interested in longer focal lengths but out of interest the Pentax 165mm F2.8 is sharp corner to corner at 1x1 binning wide open on a Proline 16803.

I conclude from this that lens makers have compromises enter in when they make short focal length faster lenses and longer focal length lenses are more likely to be useful than shorter focal lengths. And if you want shorter focal length lenses then there is no point in getting F1.2 type lenses.

There is also a Pentax 67 45mm lens. But per reviews it isn't as sharp as the longer focal length. The 75mm as I recall is considered very sharp. There is a list of Pentax 67 lenses and their ratings if you are interested.

Greg.
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