Exploring and understanding colour negative film

[glass]

When I moved to 120 film from Medium Format digital, I did a lot of testing to understand film latitude and how best to optimise exposure and development.

The test method I used was to set camera exposure based on an incident reading, then shoot a color checker chart, a black cloth shirt and a white cloth shirt. My aim was to work out how much I could over/underexpose the scene, and still retain texture and tonality in the black/white shirts. This would give me the total usable latitude of the film.

I then wanted to establish the 'optimal' exposure value of the film, assuming the total dynamic range of the scene was around 3 stops. For a 3 stop scene, would the colours, tone curve, film grain and scanner noise be 'better' (my subjective view) with mid grey at box speed, under or over exposed?

Film	My subjective optimal exposure (vs box speed)	Black cloth retains slight tonality, no texture	White cloth retains slight tonality, no texture
Fuji Pro 400H	+2.5EV	-1EV	+6EV
Kodak Portra 400	+0.5EV	-1.5EV	+6EV
Kodak Portra 160	+0.5EV	-2EV	>+7EV (scanner limited)
Kodak Ektar 100	+0.5EV	-2.5EV	+3EV

The highlight limit of my Epson V850 Pro scanner was around +5.5EV, after this the whites would be too noisy. This was using Multi Exposure mode and SilverFast. I suspect with a professional scanner, Kodak Portra 160 would exceed +7EV.

Regarding highlights, these could be further extended by Pulling during development. For all the tests above, I used Tetenal Colortec C-41 and stuck precisely to the temperature and times specified. My agitation method will have an affect, as will my metering technique, but my results should be replicable to within +/-1EV.

Summary
I would not shoot Fuji Pro 400H at box speed. At 400 I find the film muddy. However, at 100 it looks gorgeous.

For the Kodak films, their box speed seems more realistic. I consistently found increasing +0.5 stop gave better colours, contrast and saturation for a 'normal' scene, but that could be my metering method. (It isn't my camera as I'm using flash).

If I were shooting an event and I had limited time to setup each shot, I'd want to be shooting Portra 400. This film lets me get away with really bad settings! The resulting photo may not be optimal, but it will still be saleable.

Portra 160 trades speed for even extended latitude in both shadow and highlights and finer grain.

Ektar 100 is different. This film records an enormous amount of detail and offers amazing tonality and picks up subtle changes in hue. It appears to trade highlight range for increased shadow detail and colour information. Having so much tone and colour detail captured makes Ektar a pleasure to work with in post processing. However, I find if exposure is out by more than 1 stop, results can be poor and a pain to fix in post.

Conclusion
Fuji Pro 400H is what enticed me to move from Digital to Film. Ektar 100 is what enticed me to stay! Portra 160 and 400 are great, but for their purpose I would probably stick with MF Digital.

 

[soulstar89]

thanks for the testing and write up.

 

[Pioneer]

Thanks. Good write up.

I usually prefer working with black and white but when I do work with color film 8 times out of 10 I am using Portra 800.

 

[DREW WILEY]

The problem with your methodology is that you are thinking as if the dynamic range of a black and white film were involved, rather than how specific hues reproduce best along the scale. You also fail to disclose exactly how you are metering. I don't want to make too much fuss of this; but based on a great deal of experience, I would never recommend exposing Ektar at other than box speed (100). You have to expose it just as carefully as a slide film. And being higher contrast than the others, it is also very important to filter at the time of the shot for serious imbalances in lighting Kelvin temperature. For example, on a clammy overcast day when the illumination is rather bluish outdoors, you need something like an amber 81A warming filter at the time of the shot; otherwise you'll get a cyan shift almost impossible to post-correct. But it sounds like you're on your way to some extent, so have fun! Ektar can do amazing things once you really understand it. I've been printing 8x10 Ektar sheet film these past few weeks, but optically, using an enlarger in the darkroom. I printed a few 6x9 roll film shots too, with equally good results.

 

[GLS]

I usually prefer working with black and white but when I do work with color film 8 times out of 10 I am using Portra 800.

Sounds expensive!

 

[halfaman]

I have always use Fuji 400H for the splendid tones in caucasic skin but I don't like it for general photography. Too soft and dull and also grainier than Portra 400.

Portra 160 is the all-around film for me regarding the color palette and contrast. Next would be Portra 400, a real workhorse.

 

[MultiFormat Shooter]

I did a lot of testing to understand film latitude and how best to optimize exposure and development.

Impressive write-up! Thanks for sharing.

 

[Gimenosaiz]

Hi!
Thank you for sharing this, I enjoyed a lot.
I use Portra 400 and 160 most of the times that I shoot color. I think that Portra 400 can be pushed +1, but I prefer to overexpose it. Its tones and textures are not as realistic as Fuji 160 but depending on the scene I prefer Portra over Fuji. That say, I think that Fuji is more "digital" than Portra and in some circunstances I prefer this. Soooo ... I love all of them
Kind regards,
Antonio

 

[Sirius Glass]

A few weeks ago I accidentally shot Portra 400 and ISO 3200 and all the negatives printed well.

 

[soulstar89]

A few weeks ago I accidentally shot Portra 400 and ISO 3200 and all the negatives printed well.

wow thats three stops under exposed.

 

[Sirius Glass]

A few weeks ago I accidentally shot Portra 400 and ISO 3200 and all the negatives printed well.

wow thats three stops under exposed.

I would guess that it would have gone further under exposed and still produced usable prints. Many photographers do not realize that black & white and color film can handled fourteen levels of exposure, unlike the films Ansel Adams used. The problem is getting all the exposure levels on one sheet of paper. That is why for many all the endless mindless Zone System testing for black & white film can be reduced to Zones 0 & 1 and Zones 9 & 10 to get the limits. But for most, they can use a spot meter so pick an area to set in Zone X and set the lens for the equivalent Zone 5. On the other hand endless mindless testing does help the film manufacturers' bottom line.

 

[foc]

I would guess that it would have gone further under exposed and still produced usable prints. Many photographers do not realize that black & white and color film can handled fourteen levels of exposure, unlike the films Ansel Adams used. The problem is getting all the exposure levels on one sheet of paper. That is why for many all the endless mindless Zone System testing for black & white film can be reduced to Zones 0 & 1 and Zones 9 & 10 to get the limits. But for most, they can use a spot meter so pick an area to set in Zone X and set the lens for the equivalent Zone 5. On the other hand endless mindless testing does help the film manufacturers' bottom line.

I think we often underestimate the exposure latitude of modern film.

 

[DREW WILEY]

Just depends how deep in the dumpster you want to dive to scrounge a meal. Fourteen stops? - of what? Garbage-in/ garbage out. No black & white film can comfortably handle that kind of range without a trick developer that compresses the midtones. The ones that once could, like Super XX, are no longer made. Today's films have less range, not more. Sure, you might get something going way out of bounds with a color neg film too; but how much quality will be left?

 

[Sirius Glass]

Just depends how deep in the dumpster you want to dive to scrounge a meal. Fourteen stops? - of what? Garbage-in/ garbage out. No black & white film can comfortably handle that kind of range without a trick developer that compresses the midtones. The ones that once could, like Super XX, are no longer made. Today's films have less range, not more. Sure, you might get something going way out of bounds with a color neg film too; but how much quality will be left?

"No black & white film can comfortably handle that kind of range" ====> comfortably is the operative word. That is the possibility, but it is very hard to work with that kind of range. I have gotten fourteen stops with black & white film in the west when there is a great subject to brightness range, and again the problem it printing it on paper. While there can be that wide a latitude on film, sticking to nine Zones allows one to work in a darkroom to print it.

 

[George Mann]

I would never recommend exposing Ektar at other than box speed (100).

We have and we do (@ 80), and it turns out just fine (with better skin tones to boot).

 

[Alan Edward Klein]

Curious what you intend to shoot? Landscapes, portraits, etc? What are you going to do with the results? Print? post on web?

 

[Alan Edward Klein]

Are you wet printing or printing digitally?

 

[Arcadia4]

There is a very interesting comparison of under /over exposure of colour negative professional film by canadian film lab; for Fuji 400H, Portra 160, Portra 400 & Portra 800: between -3 and +4 stops

http://canadianfilmlab.com/2014/04/24/film-stock-and-exposure-comparisons-kodak-portra-and-fuji/

which demonstrates the latitude of CN film; below is the comparison. In this particular scenario +2 stops was considered the corrrect exposure for the situation

 

[foc]

There is a very interesting comparison of under /over exposure of colour negative professional film by canadian film lab; for Fuji 400H, Portra 160, Portra 400 & Portra 800: between -3 and +4 stops

http://canadianfilmlab.com/2014/04/24/film-stock-and-exposure-comparisons-kodak-portra-and-fuji/

which demonstrates the latitude of CN film; below is the comparison. In this particular scenario +2 stops was considered the corrrect exposure for the situation

Excellent link for exposure comparison. Thanks for posting.

 

[DREW WILEY]

People are making apples to oranges comparisons. Some CN films, esp amateur ones, are engineered with a very wide latitude because careless exposure and less than ideal film storage conditions are likely. But something else has to be sacrificed to achieve this. Pro portrait films have their own requirements, but skintone reproduction would be a high priority. A film like Ektar is in a different category, capable of higher contrast and saturation overall, but for this reason inherently less forgiving of exposure or color temp errors. People do sometimes deliberately overexpose it; yet in most cases it's because they don't understand how to properly K balance it to begin with and default to antique generic advice about CN films, which are not in fact all the same in this respect. But an ASA 80 tweak vs box speed of 100 for Ektar is a minor preference in this overall discussion, not worth arguing about.

 

[Gimenosaiz]

Hi!

Another interesting link!

https://carmencitafilmlab.com/how-exposure-affects-film/

Cheers!
Antonio