Visible Dust Sensor Loupe
Sunday, October 5th, 2008
The Visible Dust BriteVue Sensor Loupe™ 7X is for looking inside your DSLR (any brand) in “sensor cleaning mode” (mirror locked up) so as to see dust on the sensor. If you routinely clean dust off of your sensor and you haven’t tried this product this post will change your life. I’m not kidding.
Most people who buy DSLRs buy them with a kit lens and rarely take it off so aren’t plagued with dust problems. But, more serious photographers have a variety of lenses and change lenses often and invariably, no matter how careful we are, small particles of dust can enter the camera’s chamber and land on the sensor. This dust can show up in photographs as spots. There is an entire industry built on getting rid of this dust and I’ve tried pretty much every tool that’s come along. Few work as advertised. This sensor loupe does.
Before buying this product last week my method for seeing how much dust was on my Canon 5D sensor was:
- Change image file format to large jpg (no need for RAW for test shots for dust).
- Set ISO to 1600 (no need to worry about noise in shots to see dust) so as to be able to stop down and still get decent shutter speed (Camera should be in Av mode for this).
- Set the autofocus point to the center dot if it wasn’t set there already.
- Put Canon EF 35mm f/1.4 L lens on camera because it’s relatively light weight and I can take pictures of things at close range with it. Any lens will do though, it does not have to be fast, just able to focus close to do the test in the house.
- Put a clean white piece of paper on my work table. Make sure the paper is absolutely clean, you don’t want to mistake a dot on the paper for dirt on your sensor. Put a paperclip or any small, flat object in the middle of it.
- Stop down to f/22. This will insure that dust on the sensor will show up as black or white dots on the image. If you shoot wide open (f/1.4) dust may not show up.
- Take a shot or two making sure you’re square with the paper with the center dot focussed on the paperclip.
- Pull the card and review the shot(s) on your computer.
- If there is dust, clean the sensor and repeat this process until it’s gone or you’re so frustrated that you accept the dust and shoot wide open with fast lenses from now on (that’s a joke).
This can be a tedious process and I’ve been doing it for many years, first with my 300D, then 20D and now with my 5D. The Canon 5D is a terrible dust magnet because of it’s full frame (large) sensor.
What the loupe does is eliminate the photographic part of the process (steps 1-8 above); if you can see the dust without taking pictures you can clean and then look again without putting a lens on the camera.
You still have to clean the dust off and this can be a frustrating process that seems more like you’re moving dust around from one place to another. But, the loupe makes the process shorter and that means it might be done more which makes for better photographs and less work on the computer getting rid of dust spots. Most importantly for me, when I knew I had dust that I could not get off, I hesitated to shoot at smaller apertures, even when I wanted to because I knew the dust would show up in the images. Those days are over now.
Notes
The loupe does not come with batteries, make sure you buy two CR2025 3v Lithium Batteries which can also be used as replacement backup batteries for your DSLR. The batteries are to power the LED lights inside the loupe which light up the inside of the camera enabling you to see the dust. I’d get some extra batteries, no harm in having a few extra around and they work in many things.
The loupe does not fit all that snugly on the body opening of all DSLRs and you may have to shift it around to get perfect focus. However, that said, perfect focus is attainable and you can see the smallest dust particles with this product.
There are other loupes made for this purpose but I tried and returned one because it didn’t magnify enough for my aging eyeballs. This product has enough power (7x) to do the job for me. I do wear my reading glasses but with them I can see the smallest dust clearly.
Resources
Visible Dust BriteVue Sensor Loupe 7x at B&H
Rocket Blower at B&H
Hurricane Blower at B&H (no rocket fins, smaller)
Photographic Solutions sells various wet cleaning tools. I use Sensor Swabs and their Eclipse cleaning fluid when a blower won’t remove dust or other stuff on my sensor.
Richard, this is very useful information. I’m ordering this tonight from you know where.
Gary, it’s extremely useful, I’m sure you’ll agree.
I really appreciate your review. I, too, will order one. Thanks!
Dave: let me know what you think, I’ll be curious. I’ve used it twice now and it’s a great tool.
Another suggestion: use your computer screen as the target. First, clean your screen! In a graphics application (I use Graphic Converter), create a blank document the same size as your screen (or larger, but make it the same aspect ratio, more or less). Fill it with a light solid color (the default white will do). now, do pretty much what Richard suggests, except
1) Focus isn’t all that important–just set it to the closest. You don’t need to focus on the target. (This is also true if you’re setting a custom white balance, using a grey card for exposure, etc.) In fact, it’s better if the target is NOT focussed.
2) Instead of using a short shutter speed (you’re not taking a “real” photo!), use a LONG shutter speed–maybe 1/2-2 seconds. (You’ll see why in a moment.) I.e., set ISO low.
3) Overexpose by maybe 2 stops–otherwise, the white screen will look gray and dust will be harder to see.
4) Display the image. Don’t worry about the window margins, menu bar, etc.–you will be too close to see those. However, in some graphics programs, you can “present” the image so that it fills the screen.
5) Hold the camera VERY close to the screen. Don’t bother “aiming,” as you’ll see nothing but white.
6) Press the shutter and, while the shutter is open, move the camera around in a small circle (roughly). That will help ensure that any dust on the screen doesn’t show, as it won’t be in the same place during the entire exposure.
When viewing the image, zoom in and move the image around. That can help spot small dust particles or smears–they will move across your screen. What I do is to zoom in and use the horizontal scroll bar (or hold down the shift key and use the scroll wheel on my Kensington trackball) to move horizontally across the screen. I then hit page down and go back the other direction, repeating until I’ve checked the entire image.
Addendum: display the blank target image as large as you can, for convenience.
Also, remember the image you see in the inspection step is “upside down” from the sensor. If there’s a dust bunny at the top of the image, it’s at the BOTTOM of the sensor.
George: Thanks, interesting idea.
Better to open the image in Photoshop, open levels and hit auto. Any dots in the image will be very easy to see after that.
Erik: Great idea. However, most dust is easily seen with even the most primitive image display software but whatever works.
These days I don’t even have to take test shots, I can see almost all the dust in the loupe and I keep repeating the cleaning until it’s gone.