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p.1 #17 · p.1 #17 · Great Stuff on Lenrentals .com Blog re MTF of Wides | |
wayne seltzer wrote:
Roger, Great work! But I am trying to get a feel of what your consistency numbers mean besides a higher number being better. How much difference a score of 7 vs 4 means. Also breaking the number in two, one for center and one for corners.Most of the difference is coming in the corners for most lenses?
Also MTFs for f5.6 or f8 would be more interesting for the WAs.
Looks like you are keeping that Olaf guy very busy lately!
Scott, it's just a relative number, sort of a mental summary. Doing center and outer 1/3 numbers would be better, but the graphs are better yet. I really recommend comparing those and now that The DIgital Picture is hosting them you can pull up the variation graphs for any two lenses and compare them side-by-side.
But basically if if the number gets down around 4 and you pixel peep, chances are pretty good you'll notice the variation. Either all the copies will tend to have a soft corner or with several copies you'll notice a difference in center resolution (the graphs will show you which, or if it's both). Lenses over 7 you'd be hard pressed to find a difference between two copies unless you get unlucky.
Stop down numbers for MTF are coming soon, and will be hosted in the same tool on TDP. But what we've posted so far is two months work. The stop down numbers will trickle out over the next couple of months.
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