When I was sorting through a box of junk optics and wanted a quick idea of how sharp/contrasty/and color correction, I would sit about 6' away from a TV, a good loupe in one hand, and test lens in the other... I would hold up the lens towards the TV, and with the loupe would find the aerial image point where the raster on the screen would focus...
I would clearly see how sharp the edges of the pixels were, or if there was a bleed over on the edges, if the color blobbed over those edges, and look at the overall color contrast... Then tilt the lens a little off axis and look again to see if the image degrades...
This quik test help me scan a # of lenses quickly, and gave me ideas of which lenses should be mounted for further film testing... (One old projection Petzval seem to have a unusual "signature" and ended up with machined mounts, and beautiful special effects!!!)
It takes a little practice to learn what to look for, but a useful first test...
Steve K
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