Actual dynamic range of color negative (highlights)

macmx

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Hi there,

I often find myself in a situation with a high contrast scene, where I have deep shadows and then just a single highlight (such as a window or a bright wall), where I want to retain some highlight details, but otherwise get as much shadow detail as possible.

Does anyone know, how many stops I can overexposure color negatives (Portra 400 and 160)?

People say that color negatives "love light" but there must be some upper limit. If I knew this upper limit, I would know how much I could overexpose and not risk blowing out the highlights, rather than exposing on the safe side, and losing some shadow details.

I don't mind bringing down the brightness in post - simply trying to get as much detail as possible.

I am thinking of a scene such as the image below.

TrineSondergaard_Interior_37_copy-987x987.jpg


Any help is much appreciated. Thank you.
 
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It's a bit of a myth that color neg has a lot of exposure latitude. It's actually fairly limited for "best results," though "decent" results are nothing to worry about. For slower ISO 100 films, you'll see color shifts after about one stop overexposure, and about two to three stops for ISO 400. Highlights lose contrast a couple stops later. Both will get grainier and less sharp with more exposure, of course.

Best bet is to shoot ISO 400 film, expose for the indoor scene, and live with the resulting window scene. Or do what the pros do: stick ND gel on the glass or hang it up outside.
 
Years ago I did a test with some of the Portras for exposure latitude. It’s one of the albums on my Flickr. Over and underexposed, normal development, and then scanned and corrected to look normal. You can compare the nominal exposure to the grossly overexposed ones.

Long story short, expose for the room and you likely get decent highlight capture or the window. Will it lose contrast or exhibit some color shift? Possibly. But it will still be pretty good.
 
Yes, you will get noticeable color shifts as you reach the upper limits of negative density with Portra 160 and 400, but there will likely still be some information on the film, even in a situation like the example. Your result, if we're only talking about digital presentation, will depend a lot on the dynamic range and responsiveness of the scanning hardware you are using. You might have to combine information from two scans of the same negative, if your equipment cannot compress everything into one single scan.
 
Portra 400 highlights

Portra 400 highlights

I've seen some tests done by shooters and labs that show Portra 400 with a density corrected scan looking great 4 stops over.

Here are a couple images I shot exposing for the shadows, letting the highlights fall where they will. I remember the wheel barrow shot was wide open f:3.5 1/15 at about 9am. So you can figure how over the par outside the hall was.

I recently had a camera malfunction and the shutter didn't close before exposure ( medium format SLR) I thought I was at 1/1000 but was probably at 1 or 2 seconds. Big weird color shifts there.

LP doorway copy by Chip Greenberg, on Flickr

old church by Chip Greenberg, on Flickr
 
I would also like to suggest flash. It's fairly easy to illuminate a room with a strobe and meter for the window to get a perfectly even exposure of both in-and outdoors
 
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