Welcome to the third instalment of my Long Exposure Test series. In this part, I am looking at 5 readily available colour negative films and how adjustment of longer exposure times effects the outcomes. As with previous two articles in this series, I am attempting to refine the long exposure techniques for the purposes of my ongoing Where We Meet photography project.

For this part, as we are dealing with colour negative film, so methodology and processing requires a bit of a tweak. Here’s what’s covered in this article:

Test Methodology

In picking the methodology, my intent was to limit variability to the film alone as much as practically possible. 


For tests in this part, I used a Mamiya 645 Pro camera with a 45mm Mamiya Sekor C lens. Where required, I attached Cokin ND filters to extend the metered exposure time. 


For all films, I have used my go-to C-41 development kit, Argentix C-41 Powder Kit. This is 1L powder kit is packaged for retail distribution in Canada by film friend Jacques Brodeur at Argentix. 


Light metering was performed for mid-tones using my iPhone 6 and the Pocket Light Meter app. Over the last few years, I have found this app quite useful and effective for both digital and analog photography. Unfortunately, it looks like this app is no longer maintained, so this would be one of the last projects where I have used it. 

Exposures and reciprocity failure

The aesthetic of colour photography that I am aiming for in long exposure is somewhat different than black and white. Since I am looking to deliberately underexpose shadows for richer colours, exposure test cases are expanded.
For each film, four exposures are made – at the metered value (highlights less one stop), 2x metered exposure, 3x metered exposure, and 5x metered exposure.

All exposures are made during the blue hour time – morning twilight or just around sunset, at some of my favourite locations along Toronto’s Waterfront – Tommy Thompson Park, Colonel Samuel Smith Park and Humber Bay Park East.

Films tested

This is the third installment of the long exposure tests. Previously I covered low speed black and white films in part one and high speed black and white films in part two.

In this article, I cover the following colour films:

  • Kodak Professional Ektar 100
  • Kodak Professional Portra 160
  • Kodak Professional Portra 400
  • Kodak Professional Portra 800
  • Fuji PRO 400H

EM keeps hinting at part four but as I mentioned previously, we will keep this under the wraps for the time being 😉 


Kodak Professional Ektar 100

True to Kodak’s marketing claim, Ektar delivers vivid colours, particularly when slightly underexposed and/or overdeveloped. In long exposure situations, this film seems to be closest to “reality” exposure at the adjustment of 2x of time metered.

A more important characteristic to note, however, is the creative latitude this film offers, from deep and rich tones of a full colour spectrum to a cool and washed out tones of overexposed film, as can be seen in the fourth frame below, exposed at 5x metered exposure. For me, as noted in Blue Hour article previously, the preference is exposure as metered.

Kodak Professional Portra 160

Portra 160 delivers a stunning consistency of colour and well balanced tonal range. The reality exposure for Portra 160 in long exposure scenarios seems to be with the adjustment of 3x metered exposure time. Over four exposures, variability in colour spectrum and rendering is marginal, with purple tones getting more pronounced with extended exposure time.

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Shorter exposure delivers a more of a blue tone. The red side of the spectrum is more prominent, however, when longer exposure times are used. Portra 160 offers solid range with consistency in colour spectrum that is truly impressive. This allows for a very manageable dynamic and tonal range.

Kodak Professional Portra 400

I was truly surprised to see a pronounced difference in behavior between Portra 400 and Portra 160. Unlike Portra 160 and very much like Ektar, Portra 400 offers the richest tonal palette when slightly underexposed.

Just like Ektar’s, Portra 800’s “reality” exposure adjustment seems to be 2x metered time. The tonal range changes slightly as exposure time is extended. From deep and rich tonal range of “as metered” exposure to a washed-out teal quality of predominant blues when exposure is adjusted 5x metered time.

Portra 400 offers a solid balance between creative colour variability and consistency, but is most certainly behaving in a way inconsistent to Portra 160.

Kodak Professional Portra 800

Long exposure and a high-speed film are always somewhat of a contradiction. Still, for completeness, I evaluated Portra 800 in this test as well. Surprisingly, “reality” adjustment for Portra 800 seems to be full 5x metered exposure time. Tonal range is at its best when exposed at metered, or underexposed by about 2 stops, but dynamic range seems to be optimal with full 5x exposure adjustment.

Otherwise, Portra 800 is as consistent and balanced in terms of colour spectrum. With Portra 800, one can count on colour rendering with minor variability in purples, which seems to be inverse of what was going on with Portra 160.

Fuji PRO 400H

Putting Fuji’s PRO 400H through long exposure paces was a mystifying experience. This film is solid and consistent, “reality” exposure is set at 2x metered in a long exposure situation. Pro 400H renders colours in a very cold fashion, quite unlike Fuji’s slide favourites or Kodak Ektar.

Some can see this as an advantage, when a cool pastel look is called for. Of all films tested, Pro400H delivers the most consistent performance in terms of colour spectrum and dynamic range as one tinkers with exposure times.

Part three conclusion

The joy of film is total absence of a “correct” answer to use of the medium. Thanks to advances in digital, the world of correct exposures and accurate colour temperature has freed up film world to creative experimentation.

The long exposure tests I conducted just reaffirmed the richness of creative options film photography offers.

It is often assumed that C-41 emulsions restrict creative options due to a limited variability of the development process. Colour negative films offer a great potential for experimentation and different feel to images. While my preference for Where We Meet project is slightly underexposed Kodak Ektar 100, I am saving printed copies of all 20 images above for a future reference.

This adds to a catalogue of ideas for future projects and experiments!

~ Toni

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