Mixing Portra 160 & Portra 400

[berarthbun]

Last year I started to start shooting more color film. Mostly I use Portra 160 sheet film. This year I'm looking to shoot more medium format film. To that point I have a question regarding the mixing of Portra 160 and 400. I'm getting ready to shoot a joiner style image of an old rusted truck in a field on medium format. There could be around 175 or so individual shots that make up the entire image. I have enough film on hand if I use both Portra 160 and 400 for the shots. The finished negatives will be scanned and printed at a size of 4 1/2" x 4 1/2". I can't imagine that there would be any noticeable difference in grain structure between Portra 160 and 400 at that size. I'm not looking to nit pick the difference. If there is any noticeable difference, it could actually work for this particular image. I welcome all opinions.

 

[Paul Howell]

You might want to look at the data sheets for each film to how different the curves are, you may find a difference in contrast that could be noticeable in your project.

 

[BrianShaw]

Grain-wise, you won’t see a difference. Color-wise, you probably won’t be bothered by a minor difference.

Since you are not nit-picking, I think you’ll be fine. Enjoy.

 

[MattKing]

Looking at the curves, there are some slight differences in spectral sensitivity.
If your project was one that required nit-picking, that might mean that you needed to be careful with light sources in order to have consistency.

 

[Lachlan Young]

I've attached the official Kodak comparison of Portra 400 and 160. Other than that, 400 is a little warmer in overall 'neutral' balance.

 

[Sirius Glass]

You could get the film speeds mixed up and shoot some rolls at the wrong speed.