Wednesday, 17 February 2010

Pinhole Camera Photography Project

Part III of IV : Exposing & Developing The Negative Image

In the first post of this series I covered the historical significance of pinhole photography and in Part II we constructed the camera itself. In this post (Part III) we'll expose and develop a negative image on to bog standard photographic paper.

Talking of bogs; a quick word about darkroom and safelight requirements. Before we can load photographic paper into the camera we need a room that's completely dark. Even the smallest amount of white light can spoil the paper. I'm using an internal loo but in winter almost any room can be used at night with curtains closed. Running water nearby is useful but not essential. I always have the "developer" bath on the left, "fixer" bath in the middle and clean water bath on the right. Knowing where everything is before you turn the light out is important for anything you plan to do in the dark.
We are not working with negative film so we can use a red safelight in the darkroom. I'm using a homemade red safelight put together from a small torch, rubber band and a sheet of red cellophane (the cellophane is included in the kit).
Wrap the cellophane around the torch head and rubber band around the cellophane. (n.b. the power of the torch bulb should be no higher than 7 watts and it should be no nearer than 4 feet from where you are working). You'll quickly get used to working in low (red) light; just give your eyes a minute or two and they'll soon aclimatise.
Now it's time to create the pinhole itself. Push the needle through the hole in the outer box (as near to the centre possible) and into the internal black card box. Make the hole as clean as possible, turning the needle to round out the hole. Be careful not to make the pinhole larger than the needle itself.
DARKROOM AND SAFELIGHT ONLY : ACTIVITY
Take out a sheet of photographic paper. With the shiny/emulsion side facing the front of the camera slide the sheet of photography paper fully down the back of the camera. You will be able to detect which is the emulsion side; it will feel more glossy and smooth. Put the lid back on and wrap the two elastic bands around the camera to hold the lid in place. Don't forget to close the photographic paper pack before turning on the whitelight or opening the darkroom door.
Now we're ready to shoot. Exposure times will be longer than you're probably used to, between 15 seconds and 10 minutes at a guess. So the cat, dog, goldfish, kids or F1 racing are definitely no-nos (a Scunthorpe United defender should be no problem though).

I'm shooting the view from my bathroom. It's not ideal weatherwise, that would be a sunny/high contrast day. It's a very dull day, so I'm going to give it about a 3 minute exposure. I know what your thinking. Your thinking "About?? Surely there's a more accurate way than using About!?". Well there is and here it is....the pinhole is the aperature ok? The focal length is the distance from the pinhole to the photographic paper ok? So if the hole is one inch wide and the focal length is three inches, the ratio is 1:3 ok? Therefore our aperture would be f/3 ok? You just need to measure your pinhole and apply the formula ok? Nope? Well you did ask. Try these guideline exposures instead - Bright Sun : 15 seconds, Overcast : 60 seconds, Dull : 2 minutes, Interior light : 5 minutes.

Long exposure times mean there's no way you can hand hold the camera. So you need to position it somewhere solid (a chair, table, wall, ground). When it's in position place a finger on top and open the shutter. Close the shutter when the desired time is up.
You don't need to mix (i.e. dilute with water) the "developer" and "fixer" in the darkroom with only the safelight on. They are, however, temperamental and best used at room temperature. Remember to use rubber gloves when handling them.

DARKROOM AND SAFELIGHT ONLY : ACTIVITY
Remove the camera lid and take out the photographic paper. Using the tweezers, slide the paper into the "developer" (shiny/emulsion side down) for 10 seconds. Turn the paper over and gently rock the bath (agitate) back and forth to remove trapped air bubbles. Watch the negative image appear on the emulsion and allow it to go a little darker than you think is ok (you need to compensate for the effect of the red safelight). It should take between 1 and 2 minutes.
Next, we need to stop the development process. Lift the paper out of the "developer" and put it into the "fixer" (again shiny/emulsion side down) for 10 seconds. Turn it over and agitate (the bath not you) for about two minutes. It's now safe to put on the whitelight.
Finally. We need to wash off the chemicals. Place the negative face down in the water for 10 seconds then turn over (the paper not the bath or yourself) and agitate for a further 1-2 minutes.

And that's it. To dry the negative print you can hang it on a line (inside not outside next to your laundry) with a peg or just lay it out on a suitable surface. Our own negative turned out slightly underexposed (too light). It's probably due to in-camera underexposure but could also be down to insufficient time in the "developer" bath. We can try compensate for this in the final step - "Part IV : Developing the Final Print".


Useful Pinhole Photography Links
f295 - on line community of pinhole photography enthusiasts.
Pinhole Photography : History, Images, Cameras, Formulas
Pinhole Photography Theory
On line gallery pinhole camera images


Pinhole Camera Kit Supplier
Flights of Fancy
3 Linglie Mill
Level Crossing Road
Selkirk
TD7 5EQ
Borders
Scotland

Tel : 01750 22142
Fax : 01750 22147