A Jim of All Trades

How to make a Pinhole Lens for a (D)SLR

with 2 comments

After making the Pinhole Camera Kit my sister gave me I’ve become really interested in pinhole photography. I’ve been thinking about getting or making another pinhole camera, but didn’t want to do another kit. I had heard of people making pinhole’s for their (D)SLRs, but wasn’t quite sure how it was done. My idea was to poke a hole through a camera body cap, put a pinhole in front of that, and voila – you’d be done! So, I did some searching online, and it turns out people do just that.

Doing various searches on Google one should be able to find different blogs and instructions on how to go about making a pinhole for an SLR. But, since there aren’t nearly enough blog posts about the same subject matter on the internets, I’m going to go over the steps again here.

This is really easy; pretty much everything can be done with household items and you don’t need to be especially mechanically inclined to do it.

Here’s a simple break down of the steps:
1) drill a hole in a camera body cap (the cap itself isn’t the pinhole; you attach a pinhole to it later)
2) make a pinhole in a piece of foil or aluminum
3) fasten the pinhole to the lens cap
4) put it on your camera

Easy.

Okay,  on to the steps in detail:

First off, you need a body cap for your SLR. If you only have one I highly recommend getting an extra one (or two). You’ll be sanding it and drilling a hole in it, so it wouldn’t be wise to disfigure your only body cap. They’re cheap, I got one on eBay for $2.50 delivered.

Begin by sanding its front (the outside surface) down. This might not be necessary but is a good idea. Basically you want to make it smooth and it’ll thin the material which will make it easier to drill through and reduce the risk of shadows or light obstruction.

I put sand paper on a sanding block and simply rubbed the cap back and forth, rotating it as I went to make sure it worked down evenly. I used a mid-grain sand paper to start, then finished with a really fine grain piece. Afterwards I washed the cap and dried it thoroughly to make sure no dust was left on.

Next, you need to find the center of your cap.

I used a digital calipers and double checked with a tape measure. A ruler would work fine. Mark the center with your skull and crossbones pencil. (you can see in the pic that I have a couple of markings… it took me a couple tries to get it right.)

Before drilling, I think it’s smart to make an indentation for the drill bit to seat into. I used a small push-pin and made a small indent so the drill bit would sit right in the center with little chance of moving.

Next you drill a hole.


(you actually want to drill down at a straight 90 degree angle to the cap, not at an angle as pictured)

I used a 5/16″ bit, but something slightly smaller or bigger would work. If you don’t have a drill, don’t worry. After sanding the cap, mine was pretty thin and the material soft enough that I could have just pushed something through if I wanted to. You could probably use a screw and just screw it in then remove it, or push a bigger nail through. If not drilling, I think it would be wise to start with a small screw or nail, then use something slightly bigger, then something slightly bigger yet, till you have roughly a 1/4″ hole.

With the hole drilled, I took a small piece of sand paper, rolled it up, then cleaned out the inner edge of the hole. You don’t want any stray pieces of plastic hanging in there, potentially getting in your shot.

The cap can be set aside now, we’re done with it for a bit.  (and sorry, I missed taking a picture of it at this point. shouldn’t be hard to imagine though)

Next, you’ll need to make the actual pinhole. I used a left over one that came supplied in the kit I got. I’ve made others already though, so will retrace the steps.

You’ll want a thin piece of metal to do this. Aluminum foil works, but it’s rather flimsy. The best to use is probably a piece of aluminum from an empty soda can. Whatever you use, cut it to about one square inch. I’m using aluminum foil for the demonstration.

In the center (doesn’t have to be exact), very lightly press straight down with a sewing needle, and continually rotate the needle as you’re pressing down.

You do NOT want to just push the needle through. ONLY THE TIP should puncture. The hole will be so small that you’ll need to hold it right to your eye and look straight at a light to be able to see through it. We’re talking small, like .2 millimeters-ish.

That’s the hole in the center.

It doesn’t take much force to push through foil, but if you do use an aluminum can, which I would recommend, it will take more effort. Just remember to keep twisting/rotating the needle as you push down. This is done to make a nice even circle with smooth edges for the light to pass through. With a can, you might need to start from one side, then flip it over and finish from the other. It can be hard to do, but makes for a nice durable piece with a smooth-edged pinhole, and that makes for nice uniform pictures.

Before attaching the pinhole to the cap, you want to “black off” the metal. This is done to reduce reflection that can mess up your shots. Some people use black paint or magic marker. I use black photography tape that came with the kit. It’s basically just black masking tape, so if you can find it anywhere, I’d recommend getting it.

I covered the back of my pinhole so that no exposed metal will show when it’s attached to the cap, then covered the entire front of it so there wouldn’t be any reflective surface showing and taped it to the cap.

Here’s a shot from the back with it taped to the cap:

You want it to be centered in the hole you made in the cap (which should itself be centered), so this might mean measuring the placement of the pinhole in the cap. I honestly just did it by eye. The risk is that if it isn’t centered, the images won’t center on the film or camera sensor, and the edges, top or bottom will get cut off.

Also worth noting: Some people even black out the middle with a black marker, but I haven’t tried that. The ink could actually get in the pinhole and obstruct light getting through. I’ve had fairly good results with just a hint of the metal showing in the center, so am leaving as is.

Lastly, just put the cap on the camera, and you’re done!

I am using a Canon A-1, which is a film SLR, so I will not have any sample photos until I finish a roll. I almost hesitated posting this because it would suck if none of the pictures turned out, but I’m pretty confident I’ve done everything correctly and what’s the fun in waiting. There is a lot of other info out there on the web, too, so please do your own research if you’re considering this. With a DSLR, obviously, you’ll be able to tell right away whether it works or not.

This really is easy to do, it only took me about a 1/2 hour, and I was stopping to take pictures along the way. If you’re at all interested in pinhole photography, I hope this helped somewhat; give it a shot!

Written by Jim

April 29, 2012 at 12:55 am

2 Responses

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  1. A very insightful post =)

    ishooteditnblog

    April 29, 2012 at 1:34 am


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