- Banned
- #21
Pawel Achtel
Banned
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- Oct 12, 2007
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- Location
- Tasmania
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- www.achtel.com
pixel size 30.7mm / 6144 px = 0.005 mm
which gives 200 ln/mm, which is 100 lp/mm
The Nyquist resolving limit would be at 10 microns (100 lp/mm).
Not many lenses can achieve such performance consistently across the entire frame especially at wider apertures. But, they may be fine at f/5.6.
Besides, you don't want the lens to resolve 200 lp/mm, but you do want a lens that has decent contrast at around 50 lp/mm spatial frequency.
We have done hundreds of lens testing using SFR (spacial frequency response) charts and produced MTF at various points in the frame at various f - stops and can do so as a service for your specific lens.
Also, we have been able to resolve beyond the Nyquist limit of the sensor, like this 8k sample frame grab: http://www.flickr.com/photos/achtel/8839311952/
And, for that you do need a lens to resolve 200 lp/mm
which gives 200 ln/mm, which is 100 lp/mm
The Nyquist resolving limit would be at 10 microns (100 lp/mm).
Not many lenses can achieve such performance consistently across the entire frame especially at wider apertures. But, they may be fine at f/5.6.
Besides, you don't want the lens to resolve 200 lp/mm, but you do want a lens that has decent contrast at around 50 lp/mm spatial frequency.
We have done hundreds of lens testing using SFR (spacial frequency response) charts and produced MTF at various points in the frame at various f - stops and can do so as a service for your specific lens.
Also, we have been able to resolve beyond the Nyquist limit of the sensor, like this 8k sample frame grab: http://www.flickr.com/photos/achtel/8839311952/
And, for that you do need a lens to resolve 200 lp/mm