Or: Where's my 5000dpi test-target?
In preparation for some macro-testing I'm still at a loss where I can get a test-target with enough resolution for say 1:2 testing. We're talking about a target with 100-200 lines per mm (simple calculation: The sensor of my D300 has approx 200 scan-lines per mm): this is 2500-5000 dpi!
Unfortunately non of my printers can resolve anywhere close as we're talking here about clean black/white transitions, not some fake 2400 dpi dithering with multiple ink-blots
I was thinking about using a optically minified (as opposed to magnified) version of the Siemens-stars I usually shoot. Imagine holding a 50mm lens at 1m distance aiming at a standard target. Behind the lens there is an image of the test-target that is 20 times smaller than the original, with a resolution that should reach and exceed the sensor resolution. If you now place the camera with the mounted macro-lens pointing at the image you should be able to capture an image of the projected test-target and see how the macro-lens resolves it.
Well, trying this setup handholding shows me that it could really work, but only if you align everything up perfectly and keep the 50mm's aperture open at something around f/5.6.
But what I'm really wondering is: Do you have any ideas of a test-target for macro-shots?
Thomas (beware: Nikon-fanboy and moderator!) My Lens Reviews
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