House dust

Images taken in a controlled environment or with a posed subject. All subject types.

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Chris S.
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House dust

Post by Chris S. »

Am working out a protocol to photograph captured airborne particulates for a friend's thesis defense. We expect some components of the particulates to be repelled by glass, so here tried stretched Glad Wrap (kitchen plastic wrap) to hold the dust. Wanting to first work with something other than the lab specimens (we have a limited supply), I tried some house dust. Not surprisingly, it appears to be composed primarily of human skin flakes. There were also numerous larger textile fibers, which I did not include in this view.

The scale bar is a bit hard to read at Web resolutions; it's 50 microns. Nikon CF M Plan 40x SLWD objective, 45 frames @ 0.001 mm ZS DMap. D200 on the Bratcam.

Image

Tesselator
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Post by Tesselator »

Primarily human flakes? Come to my house and I bet you'll find primarily clay and cedar wood particles. Living in a traditional Japanese mud house there's thousands of times more dust from it introduced into the environment than all of the total living human skin contained in it. Kinda of a drag for a photo-studio but at least I know the particles floating in yesterdays coffee aren't old pieces of me. :)

Pretty cool image BTW! Everytime I look at dust through the mic I'm always expecting to see mites and stuff... but never do.

Chris S.
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Post by Chris S. »

Tesselator, your home sounds like a really hard place to keep a sensor clean. That aside, must be an amazing place to live.

I don't see dust mites either--hmm. I had thought they were too small, but after reading your post I looked them up, and it seems that some species should indeed be in the size range we can observe with visible light. Makes me suspect it might be dependent on where one gathers the dust sample. Not sure I really want to find out what I can collect from, say, my pillow. As you say, it's bad enough to think about what is landing in my tea.

Thanks for the good word. Skin flakes don't seem to engender the same interest as, say, flowers or bugs. I know that dust images are pretty routine for microscopes, but was pretty happy to be able to do it with camera on bellows.

Cheers!

Edited to correct typo
Last edited by Chris S. on Fri Apr 23, 2010 10:53 pm, edited 1 time in total.

PauloM
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Post by PauloM »

Chris,

I'm curious about the lighting arrangement. Did you put the Glad wrap against a black background, or does the Bratcam now have darkfield capabilities?

P

Chris S.
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Post by Chris S. »

Paulo,

Yes, I taped a piece of black paper to the post that holds the subject stage--so it was far enough behind the lens to be way out of focus. Lighting was a pong ball diffuser with one Nikon SB-26 speedlight shining through.

I've thought about adding a dark field capability. I can, of course, backlight through standard photographic means. Not sure if dark field would give me much more, but suspect it would.

--Chris

Cyclops
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Post by Cyclops »

Interesting image, and I wonder what those tiny orange particles are! Far too small to find out of course!
I've done this in the past and found dust mites-try lifting a carpet edge and doing a scraping!
Canon 30D | Canon IXUS 265HS | Cosina 100mm f3.5 macro | EF 75-300 f4.5-5.6 USM III | EF 50 f1.8 II | Slik 88 tripod | Apex Practicioner monocular microscope

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