Shabar Testing

We spent an evening testing out the equipment. I was trying to adapt my camera to the Shabar and came across a weird effect when using an 'occulter'. For optics geeks - it turns out that the filter location corresponds fairly closely to an image plane as opposed to a pupil plane. When you put a dot of duct-tape there, you block out that location on the sensor. A little circle of tape blocked out the sun. That tape was more in focus with higher aperture. You could also see a purpleish halo.... Strange.