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kevinobrien
05-01-2013, 01:23 AM
Hi Guys.

Here's a question for you. I was shooting pinhole images with my Canon 5DmkII on Sunday using a pinhole made from my camera cover. When I started to edit the pictures I had the scare of my life when I discovered small circles all over the images, and I mean hundreds, firstly I thought my sensor had dust all over it but all the circles are the same shape although some are lighter then the others, there are also some long black marks almost like there is creepy crawly's in my camera. I took my camera out and shot images with the normal lenses and it was fine, nothing at all. I know it has to be something to do with the pinhole but can anyone explain the exact cause please before I write to Canon and ask. They certainly are circles of confusion.

17091

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Marko
05-01-2013, 02:24 AM
maybe oil stains? I'd call and likely bring it in for a good cleaning. Check older lenses to see if u can see oil stains in them.
Try testing with small apertures...
how many images showed up with these stains and what was the aperture - small? Small apertures would show stains more.

kevinobrien
05-01-2013, 10:39 AM
I have tested all my lenses and there is nothing all the images taken with "real" lenses" are fine it's just the pinhole that causes it. it is a real mystery to me.

Realist
05-01-2013, 03:39 PM
Probably something you can't see. Since pinholes are so small I bet something is obscuring the hole and you can't see it without some magnification.

kevinobrien
05-02-2013, 06:04 AM
Ok guys I have finally worked it out with some help from a friend and it's obvious really. It's the circle of confusion phenomenon Apparently. The pinholes tiny aperture creates tiny circles of confusion on very tiny dust particles that normal lenses would not pick up. Something to remember maybe, especially in pinhole photography. I could kick myself for not remembering this I did it at College, another case of learning something and then not remembering it. but thanks for helping out guys.

Marko
05-02-2013, 07:26 AM
sorry to scare the crap out of you with the oil remark then - I have seen oil stains that resemble these though. Glad it's nothing :)

Matt K.
05-09-2013, 09:11 PM
wow, those are orbs, they are invading your camera body. Quick, get an exorcist and get rid of them .... but in all honesty, this is really weird. might be refractions ... who knows ...