The Sony a7R/55mm Sonnar testing with strobe illumination of the ISO 12233 target performed in the previous post got me worried. If the Sony’s shutter affects the sharpness of strobe-lit subjects with a normal focal length lens, would Nikon D800E mirror slap suffer the same fate? I mounted an AF-S 58mm f/1.4G lens on the… [Read More]

One of the unanswered questions from yesterday’s post was, “What degradation does the variable ND filter do to the image?” Today I set out to get a handle on that. I went into a dark room and lit a smaller version of the ISO 12233 target with two Paul Buff White Lightning X1600 (1600 watt-second)… [Read More]

Let’s take a break from the simulations to look at some real pictures. I got a 77mm Heliopan ND 0.3 to ND 1.8 variable neutral density filter and some adapter rings. I screwed the 49/77mm ring onto the Sony/Zeiss 55mm f/1.8 Sonnar FE and aimed it at the ISO 12233 target, which ended up being… [Read More]

I can’t measure sub-pixel camera movement at the sensor, so I have to look for indirect ways to get at it. Are there ways to glean such information from photographs of the ISO 12233 target? I turned to a simulation study to find out. Using Matlab, I created a nearly-ideal camera with a resolution of… [Read More]

I’m looking for a way to do shutter slap testing with sub-pixel sensitivity without spending a lot of money on variable intensity LED Fresnel lights. It occurred to me that I might be able to get what I need using neutral density filters to compensate exposures for different shutter speeds. Before I get started with… [Read More]