Category Archives: Equipment

A New and Different DSLR ‘Sensor Dust’ Problem

Since I sometimes go off for a week or more to shoot in the backcountry, I’ve worried from time to time about getting a dirty sensor early in the trip and not realizing it until I return… a few hundred or thousand frames later. Yesterday I ran into such a problem on a night photography shoot and didn’t realize it until I moved the photos to my computer and checked them in Adobe Bridge.

The first few shots were fine, but perhaps a half dozen into the sequence I noticed a very black smudge near the bottom of a vertical frame image. (This means it was near the “top” of the sensor when the camera was held this way.) On the next couple of shots the “smudge” moved in bug-like fashion up into the frame, finally lodging close to the middle. This was one strange dust spot – like none I’ve ever seen before. The typical spot leaves a semi-transparent smudge on the image and generally stays in one place on the sensor. (Technically, the AA filter, but you know what I mean…) This one was black and moving – at first as I cycled from frame to frame I wondered if I had a bug crawling around inside the chamber.

Fortunately, I’ve adopted a sensor cleanliness strategy that relies more on post-processing removal than on the futile attempt to keep the sensor in a pristine state of cleanliness. So far I’ve been able to remove the offending blob from all of the images from the shoot that I’ve worked on.

If there is a moral to this story, it might be this – even if you hope to keep your sensor clean, you still need to develop the post-processing skills necessary for dealing with dust specks when they unavoidably do show up.


G Dan Mitchell is a California photographer and visual opportunist. His book, “California’s Fall Color: A Photographer’s Guide to Autumn in the Sierra” (Heyday Books) is available directly from him.

G Dan Mitchell: Blog | Bluesky | Mastodon | Substack Notes | Flickr | Email


All media © Copyright G Dan Mitchell and others as indicated. Any use requires advance permission from G Dan Mitchell.

Using the Wrong Tool for the Job: Which Lens is ‘Best’?

These are things that everyone knows about picking the right equipment for the subject, right?

Use wide angle lenses to shoot landscapes. When people ask what lens to get, I always ask them what they’ll be shooting. If they say landscape I generally recommend something wide rather than something long. Here’s an example of use of a very wide angle lens on a landscape shot:

318

First Light, Banner Peak and Thousand Island Lake

Use long lenses to shoot sports. Everyone notices all of the Really Big Lenses at sporting events. I sure saw plenty of them at this week’s Amgen Tour of California bike race. Heck, I even used one myself to get shots like this one:

887

Riding to the Starting Line, Prolog Time Trial, 2008 Tour of California

But wait a minute…

Sometimes the “common wisdom” can be exactly wrong, or at least it is possible to get interesting results by doing the opposite of the obvious thing. How about a landscape shot with a very long lens:

879

Big Sur Fisherman, Winter Surf

And here is another bicycle racing shot, done with an ultra wide lens. (That’s Mario Cipollini banking into this turn, for the cycling fans out there.)

904

The Peloton Enters San Jose – 2008 Amgen Tour of California

I’ll share one bit of technical information here. All four shots were made with two lenses. Both of the wide angle shots – landscape and cycling – were done with a 17-40mm zoom at the wide angle end. Both of the telephoto shots were done with a 100-400mm telephoto at the long end.

Just to tweak another assumption about “the right equipment,” both bicycle racing shots were done with a Canon 5D – and everyone knows that the 5D is only useful for landscapes and that you can’t shoot action subjects with it. ;-)