Saturday, August 30, 2014

Pinholing It!

I read an article just the other day that pointed out that although the high tech electronics of today’s DSLR’s may fail, memory cards may become corrupt or even obsolete, and the mechanics of all mechanical film cameras may break and be rendered useless in time , a simple box with a pinhole is forever!

There is an elemental beauty in a simple pinhole camera. The first one I made was from a cardboard kit that I cut out and glued together. I still have it and it works fine with any standard 35mm film stock. 

The photo above was taken with that little cardboard camera using Kodak Ektar color film.

The only reason I wanted and eventually got another pinhole camera was so I could use 120 film and explore the larger format. I bought a Holga pinhole camera for that, a cheap, plastic toy camera with a pinhole instead of a lens. It does have a mechanical shutter that will eventually break and when it does I can just remove the shutter and simply use the lens cap as a shutter because most exposures are so long that a shutter really isn’t needed.

A couple months ago I received another Holga pinhole camera as a gift. The WPC, or wide pinhole camera this time. The WPC is still a cheap, plastic pinhole camera but this one will allow you to shoot 120 roll film in a wide 6x9, or super wide 6x12 format (the regular Holga pinhole camera shoots 6x4.5 or 6x6). I still haven’t shot with it but am looking forward to doing so this week.

I am a bit of a camera Geek I suppose, and I like to “play” with a number of different cameras and gadgets so I will likely accumulate other pinhole cameras over time. That said, I pretty much have everything I need to take a variety of pinhole photographs with what I have already. I have researched the various films available and their properties. I have studied the work of other pinhole photographers. And I have experimented with several rolls of film over the past 2 or 3 years and I have some creative ideas so there’s really not much left to do but to go out and make some pictures and that is exactly what I intend to do. Stay Tuned!

Saturday, August 9, 2014

Reciprocity Failure

I don’t generally dwell on highly technical subjects in this blog, or rather I should say I haven’t done so for a while, but I am doing a bit of research for my current project and need to get this down somewhere where I can find it easily. I am certain I will forget most of the information I dug up on this subject within a few days so I am afraid I must bore you with it for the moment.

My current project involves exploring black & white pinhole photography. If you’ve been following this blog for any time you know I prefer color film in my pinhole cameras, usually Kodak Portra 400, and though this film is not immune to reciprocity failure I haven’t really had any problems with it, probably because my exposures rarely go longer than 20 to 25 seconds. My “go to” film for black and white photography however, is Tri-X and it is quite sensitive to reciprocity failure – thus my current quest for another black & white film, preferably with an ISO of 400.

In case you have no idea what I am talking about reciprocity failure is simply the tendency of some photographic films to become less sensitive to light the longer they are exposed to light. 

It seems odd that something specifically designed to be light sensitive should become less so simply by being exposed to it more but there it is. Like so many thing in life its just the way it is and we must learn to deal with it. Reciprocity failure is rarely a factor with exposures lasting less than a second but for longer exposures it can have significant impact. 

For instance a film with no reciprocity failure like Kodak BW400CN might require an exposure of 5 seconds in a given situation. A similar film with the same speed (ISO  400) that is subject to reciprocity failure like Kodak Tri-X or Ilford HP-5 will require an exposure of 15 to 20 seconds to properly capture the same image (this information was taken from the published data sheets for Kodak BW400CN, Tri-X and Ilford HP-5 films).  

In addition, reciprocity failure increases exponentially so that the longer the exposure the greater the failure. For example, an image requiring a 25 second exposure with the BW400CN will require an exposure of 150 seconds with Tri-X. This is a 5 times longer exposure for BW400CN but Tri-X requires an exposure 7.5 times longer for the same image. 

Since I generally prefer to shoot 400 ISO film in my pinholes I will focus on those films for now and offer the following notes:

Kodak Tri-X, 400 – If I understand the published technical publication data correctly Tri-X is fine down to about 1/10 of a second. At one second you should add one stop to your exposure. Beyond that it gets complicated and you should consult the technical data sheet (see link below) or just consider another film stock as I am doing.

Kodak T-Max, 400 – This is an excellent film stock with good reciprocity characteristics. No adjustment is required down to 10 seconds exposure. At 10 seconds the technical data sheet recommends a 1/3 stop adjustment (why bother?) and at 100 seconds the recommended adjustment is only 1.5 stops. See link to technical data sheet below.

Kodak BW400CN, 400 – No problem! Apparently this black & white film develops in C-41, color processing just like color films and is immune to reciprocity failure for exposures up 120 seconds.  Beyond that you’re on your own to experiment and find out what works but here’s the technical data sheet below.

Ilford HP-2, 400 – This is a popular C-41 black & white film like the Kodak BW400CN but unlike that film, which has no reciprocity problems, Ilford HP-2 is similar to Tri-X in its susceptibility to reciprocity failure. See technical data sheet below.

Ilford HP-5, 400 – This very popular traditional black & white film is very similar to Tri-X and HP-2 in its susceptibility to reciprocity failure. See technical data sheet below.

Ilford Delta 400 – Another black & white film similar to Tri-X, HP-2, and HP-5 in its susceptibility to reciprocity failure. See technical data sheet below.
Fomapan 400 - Another black & white film similar to Tri-X, HP-2, HP-5, and Delta 400 in its susceptibility to reciprocity failure. See technical data sheet below.

There are other 400 ISO black & white films available but I was unable to find any info on their reciprocity characteristics so I have omitted them for now. 

In conclusion, it seems that although Ilford and others have some very fine and popular emulsions if you’re worried about reciprocity failure you’re better off with Kodak. The T-Max and BW400CN both are very forgiving for exposures of up to about 2 minutes. Unfortunately the latter is only available in 35mm format but T-Max is available in medium and large formats.
I will update this information as I come up with additional data.

Oh, by the way, the image above was taken with my Olympus XA2 on Tri-X.

Saturday, August 2, 2014

Love that Black & White

According to most sources the fastest growing (yes, I said growing) segment of the film market is black and white. I like color, especially some of the newer emulsions like Kodak Portra but there are some things you can only do with black & white film.

I know digital cameras have gotten pretty good at emulating black & white but there is something different and special about images from black & white film. Each film of course, has its own distinct characteristics and should be selected based on what effect you’re trying to achieve. If you also take the next logical step and print them using the traditional or what is called today “true” black & white process you end up with a truly unique, one-of-a-kind image that you can’t get any other way.

The image above was shot at night using the Olympus XA2, a fully automatic, zone focus, point & shoot from the 1980’s on my all-time favorite black & white film – Kodak Tri-X. The Olympus XA2 is fully automatic (except for the zone focus) with shutter speeds from 1/750 to 2 seconds and apertures from 3.5 to 14.

The two trees in the picture are right outside my office window and the light you see is from a “street type” light on a pole just to the left of the frame. The XA2 does not let you know what the selected settings are but considering the composition and lighting I must assume it was f3.5 at approximately 2 seconds.

Some things are just better in "real" black & white.