*Note: the opinions rendered here are independent of Climax Photo and Digital and belong to their respective owners.
Thom Hogan is a Nikon expert, and has written a Nikon E-book series entitled "The Complete Guide to the Nikon (fill in any model here)".
You can order these books by visiting:
Thom Hogan is a Nikon expert, and has written a Nikon E-book series entitled "The Complete Guide to the Nikon (fill in any model here)".
You can order these books by visiting:
Nikon D200 Review
http://www.bythom.com/d200review.htm
...Sensor cleaning is not much different with the D200 than previous DSLRs, though there's plenty of "landing space" for swabs on one side of the imaging area. Nikon disclaims all but blower bulb cleaning. You can get to the sensor area by using a menu-based mirror lockup function if you have a full battery, but be careful about that--the camera comes with a failsafe: if the battery goes below a certain level you'll get an audible warning and the shutter will close shortly thereafter. There's been at least one report of someone not getting that warning. Always use a freshly charged battery, and don't dally in your cleaning...
Cleaning Your Sensor
Sensor Swabs: the original Sensor Swabs had a fatal flaw--the support mechanism behind the cleaning cloth was not reliable and allowed the edge of the cleaning surface to "break" (bend and reduce pressure, making it not clean well). Moreover, the support mechanism was relatively thick, and if damaged, could produce little plastic pieces that you had to clean up. No more. Photographic Solutions has produced a new version that has a full, thin, plastic "blade" behind the cleaning material. It's now possible to maintain even pressure across the edge without it collapsing, even when very wet. The blade itself is a very soft plastic and can't really be forced hard enough to damage a sensor or filter surface. While you can't quite put as much pressure on the edge as with homemade tools, that's a good thing in most ways. The one problem it may create is for some so-called "welded dust" particles (see note at end of article). But this is easily solved by making the Sensor Swab wetter than usual--which might leave streaks that you have to clean up by using another swab). On the plus side versus the home-grown method is that the Sensor Swabs are still made in a clean-room environment and come in sealed packs. Thus, they're ready to go on demand but you won't be having to worry about keeping your cleaning materials clean as you try to wrap them around a home-grown support mechanism. Yes, they're on the pricey side (US$48 for 12), but you won't be using a lot of them because of the other new tool that's available. Basically, you only use a Sensor Swab when you have a persistent dust particle that isn't removed by brush, or you have welded dust. Nikon and Fujifilm users need Type 2 Sensor Swabs; Kodak Pro 14n, 14nx, and SLR/n users need Type 3 Sensor Swabs.
By the way, it’ll probably take you a few tries with the Sensor Swabs to get it right.
The usual mistakes I see from first-timers are:
- Too much liquid is used, and a streak is left behind.
- You don’t start at one edge of the sensor and swipe past the other edge, leaving dust at both edges.
- Swiping too gingerly, which tends to leave behind a few stubborn spots (and may even make them more stubborn).
- Not holding the support nearly perpendicular to the filter (I use a very slight tilt towards the side I'm moving towards), or lifting one side and leaving dust on the filter on that side.
Trying to “rub” the filter clean (you tend to just move the dust around--once it is on the lint-free cloth, it can migrate back to the CCD if you use improper technique, such as not enough fluid, or rubbing motions; moreover, if you "rub" a really hard particle across the filter you can scratch it). - Doing the cleaning in an environment where there is lots of dust in the air!
Here's a couple of added tips for cleaning:
- Get a headlamp. The Petzl LED headlamps work great, though you look like a geek using one to clean your camera. Using a headlamp lets you put light right where you need it, and even makes it easier to see the largest dust bunnies, if any.
- Minimize the time. Because the Bayer filters in DSLRs use dye inks, I try to keep the amount of time they're exposed to light, especially bright light, to a minimum. That's not to scare you into thinking that if you leave your CCD exposed for five minutes that it'll produce poor color next time you use it; just that light accumulation to dye inks really should be minimized. If you clean in a darkish environment using an LED headlamp and don't take more than a few minutes, don't worry about it. But don't leave the camera's shutter open while you walk around the house or office looking for your cleaning supplies, decide to have lunch, watch a football game, and then come back and clean your camera! (Besides, the longer you leave the shutter mechanism open, the more dust gets into the box that you'll eventually have to clean out.)
- Don't try to see it. A photosite on most DSLR bodies is about 64 square microns. You could fit several hundred photosites onto this hyphen: -. Thus, a dirt particle that covers a photosite or two can be very small--essentially invisible to the naked eye. That's one reason why I discourage use of the Speckgrabber to clean CCDs--you can only see the really big stuff.
Note: Welded Dust This type of spot usually shows up after you've moved in and out of different humidities. The best explanation I can come up with is that it is caused by evaporation directly over the dust spot, which "welds" the dust onto the top of the filter material. In other words, the dust is no longer held just by surface tension, but has actually bonded to the surface. Pollens can be like this, too, as they are slightly wet to start with and can dry on the filter material. The telltale signs of welded dust are two: (1) you can't get it off with a Sensor Brush pass; and (2) they look like a small black spot with a vague ring around it (I call them dust pimples or dust zits, because that's exactly what they look like: a small blackhead that's forming). I've never seen welded dust appear in totally dry environs (such as Southern Utah), but you can make it appear in such places by moving your camera in and out of air conditioned places. I've had the toughest problem with welded dust in Hawaii, especially when going from high up on the volcanoes (dry) to a coastal area (wet). Condensation is a factor in this case, so you can help by sealing your equipment in air-free containers before making the move.
