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The other day I thought I'd try 'shooting a specific film', i.e., post-process all the shots from the day with one particular film emulation preset, Kodak Portra 160 in this case. But when I sat down to process my shots I wondered if it mattered if it was important to manually set the WB to 'daylight' since Portra 160 is a 'daylight' film.

I first set my shots to 5500 (~ daylight) and then ran the preset, the results were not what I would expect from Portra 160 in the same lighting. The shots were from my back yard with relatively afternoon cool lighting and I've shot actual Portra 160 in this same situation.

Is my assumption incorrect in that I should set the WB to 'daylight'? Do film emulation presets take some WB into account. In this case, I'm using the VSCO film emulation presets.

Luckily I shot some Portra 160 and some digital shots of the same scene a while back, here are the results:

enter image description here

As you can see, setting the WB to Daylight resulted in a cooler photograph than if I set it to Auto compared to actual Portra 160.

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  • \$\begingroup\$ I also use and love Portra (although I prefer the 400). I'd be curious to see your results with the preset along with different white balance selections. \$\endgroup\$
    – mattdm
    Jun 12, 2014 at 2:36
  • \$\begingroup\$ You're right, I need to post some examples, will do! \$\endgroup\$
    – Shizam
    Jun 13, 2014 at 16:54
  • \$\begingroup\$ *cough* *cough* \$\endgroup\$
    – mattdm
    Jul 12, 2014 at 7:02

2 Answers 2

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I think the problem lies in your expectation that the Portra film shots are going to strongly show the effects of different color temperatures.

While it's true that Portra 160 (or any commonly-available color film these days) is daylight balanced, color prints and scans of color negatives are always color corrected as part of the process. The photo you're trying to match has already had the white balance "fixed" by the person printing or scanning the film.

If you shot reversal film (for transparencies or slides) your expectation would be more accurate, since there's no correction applied after the photo is taken.

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  • \$\begingroup\$ Ah, hrmph, I'll have to go look back at my scans and see if thats the case in the software too. Thanks for the suggestion! \$\endgroup\$
    – Shizam
    Aug 26, 2014 at 23:31
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I think so. It seems like you may have applied the same bias to the RAW data twice. What were your results when you combined "Auto WB" with the emulation preset? Also, depending on your RAW convertor "Daylight" doesn't always exactly equate to 5500°K, 5200°K, or any other particular temperature as there is sometimes some compensation on the magenta/green axis as well as the blue/amber (color temperature) axis.

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  • \$\begingroup\$ What do you mean by "It seems like you may have applied the same bias to the RAW data twice."? \$\endgroup\$
    – Shizam
    Jul 17, 2014 at 17:06
  • \$\begingroup\$ I mean it appears the light at the time you shot was higher than 6700°K but you set the WB @ 5500°K, so you had already applied a fairly significant offset before you applied the results of the Porta 160 preset. The preset then applied additional WB offset because it likely assumed the photo was taken using either Auto WB or a WB set to the actual temperature of the light. \$\endgroup\$
    – Michael C
    Jul 17, 2014 at 22:25
  • \$\begingroup\$ " it likely assumed the photo was taken using either Auto WB or a WB set to the actual temperature of the light" I think that is the problem, the preset assumes you shot in daylight WB (or corrected to daylight WB) where I expect it should behave like Portra film which just has a color shift if you're not in Daylight. \$\endgroup\$
    – Shizam
    Jul 18, 2014 at 0:13
  • \$\begingroup\$ No, I think the presets assume you used Auto WB. And Daylight does not always have the same color temperature. If you shoot at 5200°K at high noon, your pictures are going to have a cool cast. If you shoot at 5200°K during the golden hour, your pictures will have a warm cast. That is regardless of whether you are using manual WB set at 5200°K on a digital camera or film balanced for 5200°K. \$\endgroup\$
    – Michael C
    Jul 18, 2014 at 4:35
  • \$\begingroup\$ Agreed. I would expect if I shoot with actual Portra 160 film, in different color temperatures, to result in different casts, and I'd expect a Portra 160 preset to do those same casts and thats what I want to happen. The problem is, as you see in my image example, the color cast isn't the same as actual Portra 160 film. \$\endgroup\$
    – Shizam
    Jul 18, 2014 at 16:37

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