NedL
Allowing Ads
That's about 40-50X -- maybe f4000?!?!?
One more reason to use a flash -- or in this case, a few of them -- or is that against the HOLE-Y Pin-hole Rules?
Hi Sc0rnd. I finally did photograph a bee's face for WPPD a couple years ago with that pyramid camera. Well, it was a yellow jacket but same idea
View attachment 401789
this is almost a "pinhole microscope" because it is much more than 1:1... the negative is on 5x7" photopaper and the face is maybe 1/8" wide. It's difficult to light the subject when it is close to the camera, and the pyramid shape helped a lot with that. This image took 6 or 7 hours with two bright reading lights on either side. Getting it centered in front of the pinhole was difficult. I tried a few times and one time the little hairs on top of the thorax were well defined in the image ( those are tiny! ). I'm certian this image could have been much better if I'd spent more time on it... the pinhole size was a bit too big. I was intent on making the face fill the photo paper.
In macro photography with a lens thin depth of field is a problem. A similar but less extreme thing happens with pinhole. For example, the magnification factor for a plane 1/4" from the pinhole is twice as much as the plane 1/2" from the pinhole. That makes a big difference in the "optimal" pinhole, enough that it matters to the percieved sharpness of the image.
Best thing to do is build a simple camera and give it a try! For more normal macro, like 1:1 or larger, it can do surprisingly well and the pinhole size is not so critical.
Have fun!
FWIW, my avatar image here is a pinhole photo, shot at arm's length with a modified Polaroid 210 on Fuji FP3000b. Exposure time in full sun ran under a quarter second...
is it old or do you still have some fp3000b
Hi Sc0rnd. I finally did photograph a bee's face for WPPD a couple years ago with that pyramid camera. Well, it was a yellow jacket but same idea
View attachment 401789
this is almost a "pinhole microscope" because it is much more than 1:1... the negative is on 5x7" photopaper and the face is maybe 1/8" wide. It's difficult to light the subject when it is close to the camera, and the pyramid shape helped a lot with that. This image took 6 or 7 hours with two bright reading lights on either side. Getting it centered in front of the pinhole was difficult. I tried a few times and one time the little hairs on top of the thorax were well defined in the image ( those are tiny! ). I'm certian this image could have been much better if I'd spent more time on it... the pinhole size was a bit too big. I was intent on making the face fill the photo paper.
In macro photography with a lens thin depth of field is a problem. A similar but less extreme thing happens with pinhole. For example, the magnification factor for a plane 1/4" from the pinhole is twice as much as the plane 1/2" from the pinhole. That makes a big difference in the "optimal" pinhole, enough that it matters to the percieved sharpness of the image.
Best thing to do is build a simple camera and give it a try! For more normal macro, like 1:1 or larger, it can do surprisingly well and the pinhole size is not so critical.
Have fun!
Is there a practical limit for how close you can generally get with a pinhole with good results? There are calculators to give the expected image circle and angle of view for various apertures and focal lengths, but I'm wondering if there are other optical limitations. I'm trying to remember... seems I read somewhere once that closer than a certain lens-to-subject distance starts affecting the diffraction, or circle-of-confusion? or...? Anyone doing closeups with a pinhole? Maybe 2:1, or 1:1?
From the original post back in 2008 "...seems I read somewhere once that closer than a certain lens-to-subject distance starts affecting the diffraction, or circle-of-confusion? or...? Anyone doing closeups with a pinhole? Maybe 2:1, or 1:1?"
I've been gone for a very long time. And this is an old thread. I wonder whether anyone is still interested.
When I read that question, it brought to mind one of the curious things about pinhole. I did a project involving superimposing a light drawn image upon a pinhole image by putting the film back in the holder and drawing in front of the pinhole with a bare light bulb. I was surprised to find that when I got the bulb very close to the camera, the image became blurrier and blurrier the closer I got. The reason for this is that if the object is closer to the pinhole than the film is, the image will be enlarged. Even a very tiny light can be enlarged to cover the entire film area. As the point (this could be any source, in a physical subject or just a point source of light) approaches closer, the resolution will be progressively softened. That is, it will become blurrier and blurrier.
I'm attaching two scans. One, a simple drawing. The other, an image made on 8x10 film using a bare light bulb. Where the bulb image is very small, the line or dot will be made with the light farther away. Where it is enlarged, it is closer to the pinhole than the pinhole is from the film.
What do people use to make really small apertures? I imagine the needle through a Coke can won't be good enough for the tiniest hole sizes.
I use shim stock. If you can find brass material that's the best IMO. Auto parts store or a good hardware store are good sources
I use shim stock. If you can find brass material that's the best IMO. Auto parts store or a good hardware store are good sources
First, I poke a hole. Doesn't really matter how big it is, just so it isn't ridiculously far from the target and it should be a bit larger. Then, I pound the silver with the hole. That expands the metal, closing the hole somewhat, should make it smaller than desired. Then do this back and forth, too big, too small until I get it right. The microscope also helps me insure that the hole is clean. This can take a while, and sometimes I need to start over because it's easy to get a misshapen hole. If there is crud visible in the hole, delicate cleaning with the needle usually works. Maybe compressed air, but it would be easy to blow the whole job away in the wind.
Thanks guys. That's very interesting!
I had a jeweler roll out some pure silver to .003". I have a coil of it about 1cm wide. My process is actually quite labor intensive and fairly complex. It involves using a sewing needle, a pin vice, a somewhat polished anvil, a somewhat polished peen hammer, a set of gauges, and a 50x projection microscope. The gauges are cut from hardwood, sized to 50x the target dimensions so that looking at the image of the hole on the screen, I can see how close to the target dimension it is.
First, I poke a hole. Doesn't really matter how big it is, just so it isn't ridiculously far from the target and it should be a bit larger. Then, I pound the silver with the hole. That expands the metal, closing the hole somewhat, should make it smaller than desired. Then do this back and forth, too big, too small until I get it right. The microscope also helps me insure that the hole is clean. This can take a while, and sometimes I need to start over because it's easy to get a misshapen hole. If there is crud visible in the hole, delicate cleaning with the needle usually works. Maybe compressed air, but it would be easy to blow the whole job away in the wind.
The hole is in the middle of a dome that is formed by the process, much like the jeweler's forming technique "repoussé". One very important result of this process is that the hole is in metal that is extremely thin, much thinner than the original .003". This is far superior to drilled holes, laser or otherwise, because a drilled hole is actually a tube. A short tube, but a tube. This affects the light on a wavelength level. These holes produce absolutely gorgeous diffraction rainbow effects.
The material the hole is made of should be blackened. I've heard of people using paint (!) or black marker, but the best way is to use pure or sterling silver, and then selenium toner. The silver will tarnish naturally over time if exposed to the air, but I don't want to wait so I use toner.
The holes that I make this way produce extremely high quality images. Unless enlarged, they can almost compete with lenses. Of course, a lot of pinhole users would find this objectionable. They think pinhole images should look (at worst) crude and fuzzy. But I love the quality of the drawing that I get with these.
Dominique Stroobant told me that he makes his pinholes by electro etching. We haven't compared our resolutions, but I'm pretty sure they'd match very cl
I had a jeweler roll out some pure silver to .003". I have a coil of it about 1cm wide. My process is actually quite labor intensive and fairly complex. It involves using a sewing needle, a pin vice, a somewhat polished anvil, a somewhat polished peen hammer, a set of gauges, and a 50x projection microscope. The gauges are cut from hardwood, sized to 50x the target dimensions so that looking at the image of the hole on the screen, I can see how close to the target dimension it is.
First, I poke a hole. Doesn't really matter how big it is, just so it isn't ridiculously far from the target and it should be a bit larger. Then, I pound the silver with the hole. That expands the metal, closing the hole somewhat, should make it smaller than desired. Then do this back and forth, too big, too small until I get it right. The microscope also helps me insure that the hole is clean. This can take a while, and sometimes I need to start over because it's easy to get a misshapen hole. If there is crud visible in the hole, delicate cleaning with the needle usually works. Maybe compressed air, but it would be easy to blow the whole job away in the wind.
The hole is in the middle of a dome that is formed by the process, much like the jeweler's forming technique "repoussé". One very important result of this process is that the hole is in metal that is extremely thin, much thinner than the original .003". This is far superior to drilled holes, laser or otherwise, because a drilled hole is actually a tube. A short tube, but a tube. This affects the light on a wavelength level. These holes produce absolutely gorgeous diffraction rainbow effects.
The material the hole is made of should be blackened. I've heard of people using paint (!) or black marker, but the best way is to use pure or sterling silver, and then selenium toner. The silver will tarnish naturally over time if exposed to the air, but I don't want to wait so I use toner.
The holes that I make this way produce extremely high quality images. Unless enlarged, they can almost compete with lenses. Of course, a lot of pinhole users would find this objectionable. They think pinhole images should look (at worst) crude and fuzzy. But I love the quality of the drawing that I get with these.
Dominique Stroobant told me that he makes his pinholes by electro etching. We haven't compared our resolutions, but I'm pretty sure they'd match very closely.
We use cookies and similar technologies for the following purposes:
Do you accept cookies and these technologies?
We use cookies and similar technologies for the following purposes:
Do you accept cookies and these technologies?