Ektar 100 Long exposure test 2

Triboro / RFK Bridge, 2019

I photographed this at the very end of blue hour late in the summer. The scene metered at F/ 11.5 @ 2 min. Using a phone based app for Android OS called Reciprocity to calculate reciprocity failure. An exposure time of 3 min 45 seconds was suggested. My actual exposure was rounded to F/11 @ 4 min.

I’ve observed that reciprocity failure is less of an issue with Ektar below the 15 second mark. If you rate the film at 1/2 box speed or open your exposure by a full stop in the scene you should have a good negative to work from. Beyond 15 seconds there is still more research to be done.

Long exposure on Ektar 100, Study 1

Ektar 100 over exposed by approximately 1.5 stops over in a low light situation. The scene was metered at F/32.4 @ 4 seconds. The exposure time was F/32 @ 8 seconds. There is a strong lean towards warm tones with yellow being noticeable in the highlights and red / magenta in the shadows. I like the feel and texture of this treatment of the film.

Questioning the source

I’m always trigger shy when using the internet as a source of information. Over the last week or so I’ve been deep in research mode working on long exposure calculations for a specific film stock. Like the ouroboros the internet at large has done a complete circle back to the very first answer provided by google. This time, however, it was repeated by an anon and they claimed to be its creator. When they failed to provide examples, I called them out. “Pic’s or it didn’t happen” They got upset and deleted the info they originally provided.

Reciprocity failure and Kodak Ektar 100

When using Ektrar 100 for long exposure work Kodak’s data sheet leaves any exposures beyond one second up to user tests. This is a not much more than educated guesswork at a steep price. Since I’m using a studio camera with narrow apertures and exposures of longer than eight seconds its been a rabbit hole to say the least.

The extended exposure work on Ektar film isn’t common. It’s not an easy film to work with from my research. I’ve done a deep dive on Google and Reddit. While professionals and artists are using it, no one is pushing this emulsion to its limit.

Most of the sources concur that for exposures less than 10 seconds you should expose for the metered time. However the internet is a web of contradictions, with a few sources recommending extending exposure times at one second to compensate for reciprocity failure. The most accurate measurement being offered by a phone app that caps time limits at 220 seconds. With most charts being vague at best and non-existent in all cases beyond 5 minutes.

Currently I’m working through a few test rolls exploring some simple exposure situations requiring long periods of open shutter time. If anyone is working with this emulsion in this way please leave a comment or send me a message. I am very interested in your work and process.

Abstraction in contemporary architecture

A study of light and shadow on the abstract shape of the Oculus in lower Manhattan