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02/20/2009 10:44:04 PM · #1
Any resources or tips for creating a digital pinhole cap or similar attachments? I'm looking to use it on my Olympus E-520. ' . substr('//www.dpchallenge.com/images/user_icon/21.gif', strrpos('//www.dpchallenge.com/images/user_icon/21.gif', '/') + 1) . ' tph1 pointed me to an online merchant that sells caps, but I suspect some folks here are "drilling their own" and I'd be interested to hear about that. Thanks.
02/20/2009 10:56:54 PM · #2
Pinhole resource would send you "...a .259mm pinhole, approx. focal length of 50mm (unless otherwise specified), approx. f/185" drilled in the center of an Olympus body cap.

I tried myself and drilled too large a hole. Then I put a piece of electrical tape over the hole and made a hole with a pin... Works pretty well. Worth a try if you have a body cap lying around.
02/20/2009 11:38:53 PM · #3
Maybe this will help?

Pinhole Side Challenge with tips
02/22/2009 10:20:24 PM · #4
That did help. Thanks! I tried it today.

I drilled a hole in my body cap, took a square inch piece of heavy duty aluminum foil (Reynolds Wrap, I think), and pricked the foil over a clean buthcer block surface. I spun the foil around a few times, keeping the needle in place and eyeballed the hole to confirm it was round and clear. Then I used electrical tape to tape it over the body cap and hole.

It was nighttime by the I got it all put together, but a few 10 second exposures of our (relatively) bright dining room chandelier confirmed that I did something right. The images are actually fairly sharp.

I'll post some shots soon. I want to take it out in the bright daylight this week...
02/22/2009 10:39:10 PM · #5
Originally posted by bvy:

That did help. Thanks! I tried it today.

I drilled a hole in my body cap, took a square inch piece of heavy duty aluminum foil (Reynolds Wrap, I think), and pricked the foil over a clean buthcer block surface. I spun the foil around a few times, keeping the needle in place and eyeballed the hole to confirm it was round and clear. Then I used electrical tape to tape it over the body cap and hole.

It was nighttime by the I got it all put together, but a few 10 second exposures of our (relatively) bright dining room chandelier confirmed that I did something right. The images are actually fairly sharp.

I'll post some shots soon. I want to take it out in the bright daylight this week...


Why didn't you just get a very small sewing needle, heat it up and run it through the cap?

Sanding away the side you can through with sand paper.

Saving a ton of steps.
02/22/2009 10:49:53 PM · #6
Originally posted by Man_Called_Horse:

Originally posted by bvy:

That did help. Thanks! I tried it today.

I drilled a hole in my body cap, took a square inch piece of heavy duty aluminum foil (Reynolds Wrap, I think), and pricked the foil over a clean buthcer block surface. I spun the foil around a few times, keeping the needle in place and eyeballed the hole to confirm it was round and clear. Then I used electrical tape to tape it over the body cap and hole.

It was nighttime by the I got it all put together, but a few 10 second exposures of our (relatively) bright dining room chandelier confirmed that I did something right. The images are actually fairly sharp.

I'll post some shots soon. I want to take it out in the bright daylight this week...


Why didn't you just get a very small sewing needle, heat it up and run it through the cap?

Sanding away the side you can through with sand paper.

Saving a ton of steps.


That would work, but the sharpness of the images produced by the pinhole is dependent, in part, on the sharpness of the edge of the hole.
02/23/2009 07:28:23 AM · #7
Thank you both. I was under the impression, also, that the pinhole surface had to be pretty thin. The body cap looks like it could withstand a bullet. Well, maybe not, but it is pretty thick. And if it what Spazmo says is true, then it seems like you'd get a sharper edged hole from a thinner surface.

Also, this gives me the opportunity to try different surfaces and different sized holes.
02/23/2009 09:34:37 AM · #8
Originally posted by bvy:

Thank you both. I was under the impression, also, that the pinhole surface had to be pretty thin. The body cap looks like it could withstand a bullet. Well, maybe not, but it is pretty thick. And if it what Spazmo says is true, then it seems like you'd get a sharper edged hole from a thinner surface.

Also, this gives me the opportunity to try different surfaces and different sized holes.


You are correct, the surface should be as thin as possible. The holes we're talking about here are about 0.3mm (0.012") in diameter, and in order to have a "sharp" edge that light from various angles can traverse without interference, the material needs to be much thinner than the hole diameter. Material thicker than a couple thousandths of an inch will degrade performance. Aluminum foil is perfect; it's thin and relatively soft so a smooth round hole is pretty easy to make. It's also cheap and abundant!
02/23/2009 10:18:11 AM · #9
I tried making my own pinhole for the Pinhole side challenge. I followed somebody's instructions on the web and used a piece of aluminium from a soft drink can. (You can cut it with kitchen scissors.) I used a beading needle to make the hole. (Beading needles are the finest needles you can easily get.) I drilled a hole in the center of a body cap and taped the piece of aluminium to the back of the body cap. It worked, but was a little too big to give really good results. I wound up buying a "pinhole".

I saw some "pinhole sets" on e-bay. They give you pinholes of varying diameters. They might be worth experimenting with.

Keep us posted on your experiences in pinhole making. 8)
02/23/2009 10:38:41 AM · #10
The pin hole cap that I made, I first find the center of the body cap and then drilled a 3/16 hole in the body cap took some aluminum tape (used for taping up heater duct joints) placed the tape on the inside of the cap. Took the smallest sawing needle I could find and poke the hole in the middle of the duct tape, from the inside out. Hope this helps!
02/25/2009 06:50:15 PM · #11
Okay, I did it! Not sure what I did or how well I did it, but here it is anyway.

' . substr('//images.dpchallenge.com/images_portfolio/75000-79999/76335/120/768408.jpg', strrpos('//images.dpchallenge.com/images_portfolio/75000-79999/76335/120/768408.jpg', '/') + 1) . '

My pinhole is heavy duty tin foil taped over the body cap.

Some questions. No one does pinhole for sharp images, but I think these could still be sharper. How do I get sharpness? Cleaner hole? Smaller hole?

What are the best needles to use for making a pinhole? Will I get better results using pop can aluminum? A pie tin? Brass shim?

How do I calculate the f-stop? What about the effective focal length? Seems to be about 100mm.

How can I adjust the effective focal length?

Thanks!
02/25/2009 07:10:53 PM · #12
The Feb 09 issue of Digital Camera World (a UK mag, but can be found here in the US) has an article on pinholes with DSLRs. They basically took a body cap, drilled a hole,and taped in a piece of foil with a "pinhole" in it.

Might be a fun adventure for a while...
02/25/2009 08:01:44 PM · #13
Originally posted by bvy:

Okay, I did it! Not sure what I did or how well I did it, but here it is anyway.

' . substr('//images.dpchallenge.com/images_portfolio/75000-79999/76335/120/768408.jpg', strrpos('//images.dpchallenge.com/images_portfolio/75000-79999/76335/120/768408.jpg', '/') + 1) . '

My pinhole is heavy duty tin foil taped over the body cap.

Some questions. No one does pinhole for sharp images, but I think these could still be sharper. How do I get sharpness? Cleaner hole? Smaller hole?

What are the best needles to use for making a pinhole? Will I get better results using pop can aluminum? A pie tin? Brass shim?

How do I calculate the f-stop? What about the effective focal length? Seems to be about 100mm.

How can I adjust the effective focal length?

Thanks!


Check this link. I used this years and years ago for building a 120 pinhole
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