Holga exposure mystery not solved

The exposure math of the Holga has always been a mystery to me, because it seems to violate the reliable Sunny 16 Rule. The rule basically states that if you set your shutter speed to the ISO of your film and the aperture to f/16, you’ll get a solid exposure in direct sunlight. (For example, if you had ISO 50 film, you’d set your shutter speed to the nearest number, likely 1/60.)

Admittedly, every Holga is a bit different, but I did have one of my Holgas tested with a shutter speed tester, and it came in at a fairly reliable 1/100 sec, which is what it’s supposed to be. As I found out while I measured for The facts about Holga apertures, a stock Holga has an aperture of f/13.3, regardless of the position of the sunny/cloudy switch. So with aperture of roughly f/13 and a shutter speed of 1/100, you should be able to shoot ISO 100 film in bright sunlight and have a proper exposure. (Technically about a half stop over as we’re at f/13.3 instead of 16, but that’s well within the exposure latitude of modern print films, so you should just get a little extra shadow detail).

So why the hell do I have to shoot ISO 200 or 400 film in bright sunlight to get a decent exposure, while I get underexposed mud with ISO 100, which should work perfectly? After thinking about it for a while, I strongly suspected that the plastic "Optical Lens" must have a good deal of transmission loss and was blocking two stops of light, so I set up a test: I pointed a Canon 580EX flash fitted with a Sto-Fen Omni-Bounce diffuser straight into a Holga with a Sekonic L-558R meter (which is extremely accurate and consistent) stuck in the back. I metered the flash through the camera five times with and five times without the lens in place and was fucking shocked by what I discovered: there was effectively no transmission loss. The readings averaged out to differ by only about 1/6 of a stop.

WTF??!? It’s not the lens. It’s not the aperture. It’s probably not the shutter: while I can allow for the possibility that the speed changes over time—it was over a year ago I had it tested—I consistently have the same exposure requirements with all of the 8-ish Holgas I have. What’s left? Light-eating gnomes?

Diana Hooper Bloomfield lecture: "Pinhole and Alternative Photographic Processes", NC, US

Preeminent photographer Diana Bloomfield will discuss her craft at 8 p.m. on Saturday, March 31 [2007] at UNC Asheville’s Rhoades-Robinson Hall, room 125 [Asheville, NC, US]. A question-and-answer session will follow the talk, which is free and open to the public.

Bloomfield specializes in pinhole and 19th century printing techniques, including platinum and palladium, cyanotype and hand-tinting. She received a New Jersey State Visual Art Fellowship, several United Arts of Raleigh Regional Artist Project Grants and the Maine Photographic Workshop’s Golden Light Award.

Via Pinhole Visions

Paul Beard’s homemade Holgaroid

Paul Beard's homemade Polaroid Holga back

Check out Paul Beard‘s sweet DIY Holgaroid (Holga + Polaroid) made of the guts of a Polaroid EE100 and foamcore! He writes:

This project has been brewing for quite a while, but came to a full boil when I got gifted with a couple of boxes of Polapan from Bre Pettis, MAKEr extraordinaire.

The camera was a gift from him as well, and I have regretted disassembling it for quite some time (it worked fine but the pictures were pretty ordinary. So it got chopped up).

There are Polaroid backs for Holgas but they cost money, something I have very little of. I do have time and I’m not afraid to fail, so some foamcare, some glue, a fair amount of backing paper from 120 film rolls (not sticky or stretchy like tape, and it’s light-proof) and I made a box to put the lens at the right distance.

So far pictures have been tough to get, as the days have not been terribly bright and 80 ISO film @ 1/100 second is a bit challenging.

But I’ll get some.

More photos of the camera in his Homebrew Holgaroid set in his photoblog on Flickr.

Wet plate collodion workshop with Kerik Kouklis, Philadelphia, US

Here’s a very interesting-looking workshop with Kerik Kouklis (I have it on good authority that his workshops are excellent):

Wet plate collodion, one of the earliest photographic processes, has been experiencing a resurgence of interest in recent years. This resurgence is primarily because of the beauty and uniqueness of the images created. In this workshop, you will learn how to create wet plate positive images (Tintype and Ambrotype) as well as wet plate negatives. Through a combination of discussions, shooting sessions and darkroom time, participants will learn how to incorporate this process in their own photography.

Cameras and wet plate holders ranging from 4×5 to 8×10 will be available for students to use. Students are also encouraged to bring your own view camera as well. This workshop is open to anyone with an interest in 19th century techniques.

The one-weekend workshop runs 9 am – 6 pm, May 5–6, 2007, at Project Basho, 1305 Germantown Ave., Philadelphia, PA, US.

Check out the complete workshop schedule at ProjectBasho.org, including a two-weekend pinhole workshop with Scott McMahon for Worldwide Pinhole Photography Day.

RolleiClub re-launch SL66 site

RolleiClub.com have just re-launched sl66.com, a resource site for the Rollei SL66 6×6 medium format SLR camera system.

The site says:

The SL66 was and still is the only medium format camera combining five unique features:

  • Built in bellows (5cm or 2″)
  • Reverse mounting of the lens (retro)
  • Tilting the lens up and down 8 degrees
  • Completely mechanical design
  • TTL metering with special hood SL66 (SL66 E and SL66SE have built in TTL metering)

I hadn’t heard of the system before today, but it looks interesting! A bit like the Fuji GX680, but a bit more flexible and a lot more friendly to handle (I haven’t shot one, but the Fujis are massive).