This is the first in a series of tests of the new Voigtlander macro lens. To see all the tests, scroll to the bottom of this pace — below the comments — and click on the ping-back links whose titles interest you. I received my Voigtlander 65 mm f/2 Apo-Lanthar yesterday and tested it off-axis… [Read More]
Archives for 2017
Detectability of visual signals below the noise
I saw this pronouncement on DPR today: The smallest signal we can distinguish from the noise floor is equal to the noise. Signal to noise ratio (SNR) = 1. You see people saying that, or things very much like that, all the time. In some circles, it’s conventional wisdom. There’s only one problem: it isn’t even… [Read More]
Arca Swiss P0 Hybrid head
I’m a big fan of the Arca Swiss C1 Cube. I don’t particularly like their D4 geared head, though. After using the C1 for a while, I find ball heads imprecise and unpleasant to use. However, the C1 can take a while to set up. I tried a combination ball and geared head a few… [Read More]
Interpreting Siemens Star Fourier transforms
A week ago I posted some images of Fourier transforms of Siemens Star photographs, and some interesting discussion ensued. Jack Hogan, one of the participants, has written up a guest post showing an interpretation of these plots. I am grateful to Jack for taking the time to do this. Take it away, Jack: A few… [Read More]
Lens screening pages added
I have been working through the development of a lens screening procedure for the last couple of months. For the past three days, I’ve been writing it up, and have posted it here. It’s far from complete, but it’s ready for a few people to try using it to test their own lenses. If you are… [Read More]
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