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Realist
11-18-2012, 03:49 PM
I tried to make my DSLR into a pinhole camera today by cutting out a thin piece of cardboard, and poking a thumbtack through the middle. The images are extremely blurry, and I'm wondering if the hole is to big, or if something else is the issue here. Perhaps it may not work with a DSLR. Does anyone know anything about pinhole cameras? Here are some test pics.

This one is my curtains.
16405

Here is a self-portrait from about 2 feet away.

16406

Last is some alcohol bottles, because the stereotypical drunk has blurry vision.

16407

ewaizel
11-18-2012, 07:32 PM
You can try Aluminum foil instead. That's in my experiment list with my DSLR.

Realist
11-18-2012, 08:59 PM
You can try Aluminum foil instead. That's in my experiment list with my DSLR.

Well no luck with the foil. I bet the pinhole has to move forward or backward from the sensor, not sure which way though.

Barefoot
11-18-2012, 10:28 PM
What's the in camera aperture you're using?

Realist
11-18-2012, 10:48 PM
What's the in camera aperture you're using?

I took the lens off, and put a piece of cardboard over the opening with a pinhole in it. I've heard of pinhole cameras for 35mm film, they're supposed focus everything I believe.

Doug L
11-20-2012, 09:48 PM
...pinhole cameras ... focus everything I believe.
Never tried to make a pinhole camera, but as far as I figure, the huge depth-of-field is due to the set up having a hugely long focal ratio (because of the tiny aperture). So, moving the pinhole farther away from the sensor might be best. Also, if that makes the exposures become too long (multiple seconds?), a tripod will be mandatory. I wonder if the quality (raggedness or smoothness) of the hole edge affects the image? Anyway, sounds like a fun project. Keep experimenting.

Andrew
11-21-2012, 08:46 AM
The distance of the pin hole should only change the size of the image projected on the plain of the film or sensor. In my own DSLR the camera likes to know what lens is on it and makes adjustment in software for it. Manual lenses still work but there are a few adjustments to make. Make sure everything on the camera is in a manual mode.

asnow
11-21-2012, 08:22 PM
I have no experience with pinhole cameras but here is a link from Chris Marquardt who made his own pinhole camera. Chris has a podcast Tips From The Top Floor and I'm sure if you sent him a question on your problem he would send you his suggestion on a solution

Blog || Chris Marquardt - Photography, Photo Workshops, Videography (http://chrismarquardt.com/blog.php?id=8336047228636757003)

Photography Tips from the Top Floor | The free show about all things photography with Chris Marquardt (http://www.tipsfromthetopfloor.com/)

Realist
11-21-2012, 09:19 PM
I have no experience with pinhole cameras but here is a link from Chris Marquardt who made his own pinhole camera. Chris has a podcast Tips From The Top Floor and I'm sure if you sent him a question on your problem he would send you his suggestion on a solution

Blog || Chris Marquardt - Photography, Photo Workshops, Videography (http://chrismarquardt.com/blog.php?id=8336047228636757003)

Photography Tips from the Top Floor | The free show about all things photography with Chris Marquardt (http://www.tipsfromthetopfloor.com/)

Well I found another video off of the one you posted. Apparently they make pinhole lenses out of body caps for nikon and canon. Those ones are $50. Also went on to explain that like I mentioned earlier they do have a huge depth of field, but they have soft focus. The pinhole cameras are not tack sharp by any means. Well I've learned quite a bit, it's always good to learn something new.

ewaizel
11-22-2012, 12:31 AM
I decided to also experiment a little with this. I created pinhole viewers to watch an eclipse before. I tried to apply the same approach to the camera.

As you can see below, I used aluminum foil and I created a really tiny pinhole. I mean, really tiny, probably 1/4 of a mm. This could be improved by pressing a needle against a hard surface with the foil in between.
I used an extension tube which allowed me to change the distance between the sensor and the foil.


http://www3.telus.net/ewaizel/photo/pinhole_camera.JPG


This is the result. The diameter of the pinhole affects the image sharpness. The bigger the hole the less sharp the image will be.
The distance between the pinhole and the sensor affects the magnification. The smaller the distance, the smaller the magnification. In other words, if you start moving the pinhole away from the sensor the magnification will increase.
The image below was done using a distance of about 5cm.
Almost everything was in focus, the lemon at 10cm of the pinhole and the stove 3 meters away.
I was not getting a vignetting effect like some pinhole negative cameras do. Probably because the sensor was totally covered by the image.
Good luck and keep playing.

http://www3.telus.net/ewaizel/photo/pinhole_pic.JPG

Realist
11-22-2012, 12:35 AM
Well that looks like you did a good job with that. Seems to be working like the pinhole cameras should.