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View Full Version : MTF charts explained in short simple sentences


jann1033
01-24-2007, 02:39 PM
ok read 2 articles and still don't get it...i get it's checking for sharpness, contrast etc but don't get all the saggital plane stuff and don't really know if i want to unless i need to know it:lmao:
is basically all i really need to know is it's better to be horizontal as possible with out lots of crazy dips? ( looking at 70-200f4 and 200 f2.8 canons) the prime is much more horizontal the zoom at 70 and 200 starts off horizontal then gradually dips down at the ends. so would the prime be better across the board( figure most would probably be anyway), maybe not by tons but somewhat?

boBQuincy
01-24-2007, 05:21 PM
Higher is better, flatter is better. Anything past 22mm is off the edge of our 1.6X sensors, so lenses that don't perform well in the corners are usually much better than we would expect on most dSLR cameras.

I have one of Canon's poorly rated 55-200 lenses and it isn't that bad on a 1.6X camera (it would be poor indeed on a full frame).

Some zooms (like the better L series) may be as good as some 1.6X cameras can resolve. If we are not looking at more than maybe 6-8 megapixels there may be no gain in image quality by going to primes as compared to the best zoom lenses.

jann1033
01-24-2007, 08:50 PM
thanks you lost me a little but mostly i got the flatter higher is better;)
so in part b are you saying the prime might be sharper in reality but wouldn't look any better than the good zoom on my camera body...my camera wouldn't register the extra sharpness?