Archives for March 2015

Sorry, I haven’t been posting at my usual rate lately. I’ve been sick; nothing serious, just this season’s mother of all colds. I did manage to get out a few days ago and make this image of a fallen oak tree as a storm was breaking up.   And here’s my favorite grove of trees… [Read More]

I decided that, if I”m going to be able to compare various lenses for hotspotting potential, I need to make the lighting repeatable. That means out with the old, natural light approach, and in with a completely  artificially lit technique. I started out by creating this target: I printed it on a piece of C-sized… [Read More]

There’s a thread on dpr that started with a simple question, which I will paraphrase: I’m going to Europe for a month and want to travel light. Am I crazy to go with a full frame camera and a 55mm f/1.8 lens? Most of the respondents answered in the affirmative, citing the need for versatility… [Read More]

There is an opinion that the hot spots that you sometimes see when lenses not intended for use in the infrared are used there is the result of lens flare. In other words, the light that causes the hot spot is not light from parts of the scene close to the center of the image,… [Read More]

In yesterday’s post, there were some indications of hotspotting with the Zeiss ZF.2 35mm lens. I did a test for that today. In visible light, when I look for non-uniformity in field illumination, I use an Expodisc. I was worried that that technique might induce some artifact that I don’t understand. The sky was overcast… [Read More]