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04-21-2015, 12:02 PM   #1
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Photographic Resolution Charts

I just received two double-sided resolution test charts that I bought on eBay. I plan on testing all my cameras (both film and digital) and all of my lenses eventually but I have no idea how to use them. If somebody could help me figure them out. I'll (hopefully) include pictures. I took these with the camera on my phone so the images may not be the best. I'm not even sure if I'm posting this in the right place or not.facebook.com/toddkellerkandcphotography/albums/10152686214802237

04-21-2015, 12:21 PM   #2
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Lens Testing. A Guide to testing camera lenses - Bob Atkins Photography
04-21-2015, 01:41 PM   #3
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I don't have facebook, so I can't see the charts, what is can do I babble about what I know of resolution and I'm sure someone imminently more qualified will tell you I'm dead wrong and give you the right answer.

what I know from reading a bunch of "tech specs" articles is that resolution is most often referring to Line Width to Picture Height. Basically measuring out from image center to image edge, how narrow and close together a group of parallel lines can be before they blend together. The theory being that image center is always the highest resolution of the frame. The picture height depends on whether it's APS-C or FF, obviously since a FF sensor is larger than an APS-C sensor. For example, when reading your standard MTF chart, you can stop at 15mm for APS-C sensors, but you have to continue to 24mm for FF.

With that said, the resolution chart I have basically has a bunch of groups of parallel lines in a bunch of places, with each set of lines getting progressively narrower and closer together. Each set is numbered in that 10 = 1000 and 20 = 2000 etc. If you have a lens (and a chart) that goes up to 40 (4000 lw/ph) you are reaching about the maximum resolution I've seen for any lens out there.

In terms of process, the theory would be to take a live view manually focused image at 10x the focal length and various apertures (1 stop is usually fine). My multi grouping chart allows me to tell for example if the right upper corner is better than the left lower corner, or the right center is better than the left center (which would be decentering), etc. I also would know that f5.6 might be my best center resolution but f8 I get the best corners and slightly less center. 10x the focal length may not be required, but I swear I read that somewhere....lol... so that's what I use. If you print your charts large (maybe 11x17) you might be able to get away will just filling the frame, which could be handy for long telephotos lenses. I know testing my 500mm lens at 50 meters got really tricky!
04-23-2015, 12:08 PM   #4
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Here is some pictures that I put in a album on here.

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