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View Full Version : What base color corrections do you make on your favorite color film?



Asher Kelman
3-Nov-2011, 22:44
Do you always use your color film at the rated 5500, 3200 or 3400 the MFR gives. I was told today that 100G Kodak slide film can give extra pink skin in normal daylight without a filter.

So have you found that you need base line corrections for a daylight film even when the temp of the light is 5500 degrees K and the meter suggest no cyan or magenta adjustments?

For sure there must there's a detailed discussion here of this already, but I failed to find anything on my searching.

Thanks in advance!

Asher

Daniel Stone
3-Nov-2011, 23:04
Asher,

we are lucky here in Los Angeles to have relatively even sunlight throughout the year. Take an evenly toned subject out in the sun at 11am-1pm("high noon" time approx), and photograph them. Nothing spectacular, but enough to see if that "pink skin" becomes problematic. I've personally found it to be a little blue with E100G, so I add an 81A filter if I feel it'll help. A polarizer sometimes helps clean some of the haze and blue effect on the film(especially E100G).

If you're shooting in the studio, measure the color temp of your strobes/hotlights. You can always gel the lights so you don't have to filter the lens.

I like E100G. I like Provia even more. Especially in broad sunlight. Provia supposedly has a built-in UV filter, so it helps cut through some haze, and also reduces the "bluish" effect that high-noon sun can give. Its also nice having to not put a UV filter on the lens before shooting(another thing to remember ;).

Another thing to consider: use a lab that processes your film in chemicals made by the same manufacturer as your film(Fuji chems for Fuji films, Kodak for Kodak). I've found that having E100G souped in Fuji chems tends to make them more blue, IDK why, but it has happened on more than one occasion. My Provia was fine in the Fuji chems, but when souped in Kodak chems(or so the lab told me), they came out slightly cooler than the sheets(duplicate shots) developed in Fuji chems. Maybe this has something to do with a slight difference in pH? I don't really care. I'll just toss a warming(81A) filter over the lens from now on when shooting with E100G. Not hard to do, and no extra exposure compensation necessary.

I think you're overthinking a lot of this stuff you're "planning" on doing. Just shoot it man! Then get it drum scanned and do the minor tweaks in post. Get shooting :)

-Dan

Asher Kelman
3-Nov-2011, 23:11
Another thing to consider: use a lab that processes your film in chemicals made by the same manufacturer as your film(Fuji chems for Fuji films, Kodak for Kodak). I've found that having E100G souped in Fuji chems tends to make them more blue, IDK why, but it has happened on more than one occasion. My Provia was fine in the Fuji chems, but when souped in Kodak chems(or so the lab told me), they came out slightly cooler than the sheets(duplicate shots) developed in Fuji chems. Maybe this has something to do with a slight difference in pH? I don't really care. I'll just toss a warming(81A) filter over the lens from now on when shooting with E100G. Not hard to do, and no extra exposure compensation necessary.

I think you're overthinking a lot of this stuff you're "planning" on doing. Just shoot it man! Then get it drum scanned and do the minor tweaks in post. Get shooting :)

-Dan

Interesting ideas on different MFR impacting the chemistry! When I dropped of some 100G today to The Icon lab, I was asked if I used a filter to prevent the over pink effect. I did not! So I'm a tad concerned. Will find out tomorrow. This was indoors with window light at 1-2 pm. When I got to measuring the light at about 4 pm, it was 5500.

Asher

Mark Woods
4-Nov-2011, 08:13
Hello Asher, if you're really interested in zeroing out your film, go to this link:

https://cameraguild.com/member-resources/techtips/reading-L.A.D.-plotted-characterist-curves.aspx

This is an article I wrote awhile ago about this very subject. The chemistry doesn't matter if you do the test accurately. Whatever the base CT is will be determined by reading the density of the 18% gray card. It's approximately 1.00 1.00 1.00 RGB. The densitometer is set at Status A, the same as the work print.

Enjoy the article and let me know what you think.

Drew Wiley
4-Nov-2011, 09:37
I've never had a problem mixing Fuji and Kodak chromes in the same E6 run. That sounds like a quality control issue with a certain lab. But agreed about the 81A filter.
I keep one of those in every single camera kit I own.

Asher Kelman
4-Nov-2011, 11:35
Thanks Mark!

I'm studying the article. I need some time to digest the graphs! But I can guess from that article that color correction might be very complex in the shadows.

Drew,

That seems a good idea, adding an 81A filter, especially shooting outdoors. I wonder whether the 81A filter would be good for all films. Will Crocket has published his "Conquering Color Correction" (http://faculty.mdc.edu/rabruna/Lighting%20CC%20guide34.pdf) and has a list of corrections for various films, but not 100G!


http://openphotographyforums.com/2007_OPF_AK/Will_Crockett/Neutral Rendering Point.PNG

According to Will, all the Fuji are are neutral 200-350 degrees K below the 5500 degrees K that MFRS publish for their daylight films.

I discovered a nice manual nomograph here (http://www.vetigastropoda.com/photo/mired.html) but there's also a wonderful dynamic interactive Color Temperature Nomogram (http://micro.magnet.fsu.edu/primer/java/photomicrography/nomograph/index.html) for Wratten Filters where one can drag a line connecting the original source and film-desired temperatures and then the recommendation for the best filter or no filter is given.

Working so much with digital cameras, I've been spoiled to simply include a grey card and then correct colors in processing the image later! So now, I am getting up to speed to have the light corrected for film and it's a whole new discipline that takes me back 30 years when I carried around Wratten filters! Your recommendation for using an 81A is a good start for my new thinking. Thanks!

Asher

Mark Woods
4-Nov-2011, 12:00
Asher, if you do the tests I recommend, you could write your own book on the CC for a given film. The CC filters just bring the film back to the CT you determine will give you the best results.

Hang in there! You're going to shot great images.

Atul Mohidekar
4-Nov-2011, 23:09
I use KR1.3 warming filter to shoot in the shadows, especially at high elevations, to minimize the blue/purple cast on the transparency film.


// Atul

Asher Kelman
6-Nov-2011, 10:08
I use KR1.3 warming filter to shoot in the shadows, especially at high elevations, to minimize the blue/purple cast on the transparency film.


// Atul

Atul,

How much leeway do you find you have in controlling the blue with various warming filters. Do you just work by the look of things, view through the filter or use a color meter? For a transparency, it will be what it will be so it seems to matter more.

Asher

Atul Mohidekar
6-Nov-2011, 11:44
Atul,

How much leeway do you find you have in controlling the blue with various warming filters. Do you just work by the look of things, view through the filter or use a color meter? For a transparency, it will be what it will be so it seems to matter more.

Asher

First a correction: I meant I use a KR3 warming filter, not a KR1.3. There is no KR1.3 filter, there exists a KR1.5 warming filter, but its effect is too mild, only slightly warmer than an UV or a skylight filter.

I just use my judgment to figure out when to use the warming filter, I don't use a color meter. I look at the scene with and without the filter and then decide whether it should be used. I used to carry a KR6 warming filter, but found it too strong for most occasions (except in the shadow of trees at very high altitudes, e.g. near Tioga pass on Hwy 120 in Yosemite).

Since I print digitally, I can also correct the color cast in Photoshop before printing.


// Atul

Daniel Stone
6-Nov-2011, 11:47
Asher,

It sounds like you're worrying too much about exacting color balance, IMO. I used to do the same thing, the transparencies had to be "perfect"! Yes, this is the optimum desired result, however if you're scanning your film, color adjustments can be made during the scanning process(the best way, like with drum scanners, in particular the DPL software), or after it(not the optimum way, but it can work).

Unless your final product IS a transparency(like in the commercial days, film only, which would be matted chromes for display to show A.D.'s and clients), I'm guessing your final product is going to be a print, probably digitally exposed on conventional materials, or LF inkjet. If this is so, why not just use the film that gives you the most of what you're looking for right out of the box, and then make slight corrections in the scanning process? IMO, this will give you, the artist, the greatest artistic control over your print/product, and less money in the long run(not to mention less headache) of complex filtering, color metering,etc...

Just shoot! Maybe with an 81A/B/C if you need a bit more warmth, etc...

-Dan

Asher Kelman
6-Nov-2011, 13:50
Asher,

It sounds like you're worrying too much about exacting color balance, IMO. I used to do the same thing, the transparencies had to be "perfect"! Yes, this is the optimum desired result, however if you're scanning your film, color adjustments can be made during the scanning process(the best way, like with drum scanners, in particular the DPL software), or after it(not the optimum way, but it can work).

Unless your final product IS a transparency(like in the commercial days, film only, which would be matted chromes for display to show A.D.'s and clients), I'm guessing your final product is going to be a print, probably digitally exposed on conventional materials, or LF inkjet. If this is so, why not just use the film that gives you the most of what you're looking for right out of the box, and then make slight corrections in the scanning process? IMO, this will give you, the artist, the greatest artistic control over your print/product, and less money in the long run(not to mention less headache) of complex filtering, color metering,etc...

Just shoot! Maybe with an 81A/B/C if you need a bit more warmth, etc...

-Dan

Yes, Daniel, it's for chromes for printing to Cibachrome paper in an 8x10 enlarger. It's my entry to Ciba paper and baby steps. If I start with a perfect chrome then I'll have no problem getting a great print at the outset as I'm sending that out initially. Then I'll directly expose the Cibachrome at 8x10 and then larger and larger.

I'm currently using the 8x10 as a point and shoot for my Ciba learning curve. So that's why filters are important. Of course, if I scan the image, I can always correct color before printing digitally. So I get a second chance!

Thanks again fro your input.

Asher