Colour Balancing Advice

[SeanEsopenko]

Does anybody have any advice as to what I can do before taking a picture to assist with colour balancing film? About all I know, pre-shutter, is to use a filter for artificial lighting (fluorescent filter for fluorescents, tungsten filter for incandescents). Is there anything I can do to better colour balance overcast days and shady areas?

[Peter De Smidt]

Overcast days tend to be bluer than sunny days. You could use a skylight or perhaps a slightly stronger warming filter. It really depends on what effect you're trying to achieve.

[SeanEsopenko]

Overcast days tend to be bluer than sunny days. You could use a skylight or perhaps a slightly stronger warming filter. It really depends on what effect you're trying to achieve.

Oooh, so that's what a skylight filter is for, or at least one of it's uses? I have a 1A and 1B filter (from a used camera store's $5 filter bin). Didn't know what they were for exactly but I picked them up because they were cheap.

[Drew Wiley]

There are all kinds of light balancing filters available. For outside use on days when the
light is too bluish, you want warming filters starting with 81A, then 81B, and sometimes
even 81C. These are varying degrees of amber. For precise results you can acquire a
color temperature meter to specify exactly what is needed; but these are fairly expensive. So for starters, just buy an 81A and 81B and experiment with your favorite
color film.

[Daniel Stone]

What type of film? Are you shooting negatives or transparencies? If its with chromes, then color balance is more critical, since its more of a "finished product" vs. a negative, which needs a print, or scan to see whats there.

Personally, an 81a filter is always in my bag when shooting color, it helps keep the shadows from going overly blue. I'm moving to shooting transparencies(chromes), having shot color negatives primarily the last few years. So I'm re-learning the filtering :). IMO, we get "spoiled"(if you can call it that ;)) by color negative films. They're great latitude-wise, and can deliver great results. However, filtering at the time of exposure means less work down the road, even when scanning/printing. Yes, EVEN with color negatives.

just my $.02

btw, I picked up my B+W 81A at the local photo swapmeet for $10, deals are out there if you're patient, or save up your pennies for the good stuff.

Ebay can be a great source for filters as well, but now you're competing against people here reading this thread who might have a similar predicament ;)

cheers,

-Dan

[SeanEsopenko]

What type of film? Are you shooting negatives or transparencies?

They're negatives. Now that I know the 81A and 81B filters help with shade colour balancing I should be good to go for a while. Thanks.

[Mark Woods]

If you want to zero out your color balance, a color temperature meter is necessary. Also, an overcast sky is the same color as the sun at the same time of day. There's another important issue and that is do you balance to the skylight (i.e., shade) and let the sun lit areas go warmer? Or do you balance to the sun and let the sky lit areas go cooler? It would seem from the comments that the warming is the preferred method. BTW, a skylight filter is a UV filter that is slightly yellow. A lot of people use them to protect the front element of their lens.

Hope this helps.

[tgtaylor]

IMO, the only filters that you need shooting color negative film is UV, Polarizer, Neutral Density (both solid and split) and the 85 series if you will be shooting daylight film at night or visa verse or under other lighting conditions such as tungsten lighting. All other color corrections are best made in the enlarger when printing.

Rather than getting circular filters which fit only one lens diameter, I'd invest in a Cokin Z filter holder and a few step-up lens adaptors to fit all my lens to the largest Cokin adaptor which I think is 82mm for the Z holder. Then each filter that you but will fit all your lens now and those that you will acquire in the future. The Z takes 4 inch filters which are available from several manufactures at varying prices. Lee makes a Foundation Holder that is practically identical to the Cokin Z.

Pick-up a book on using potographic filters at your local camera store or library and check out the holders and filters on the B&H website.

Thomas

Thomas

[Mark Woods]

Here's a power point from the Kodak website that lays out color correction by using filters. I disagree with the point about correcting in the enlarger. My explanation is a bit long and very technical. It is always best to optimize the image capture with both the correct exposure and correct color temperature for the effect one is after.

[Mark Woods]

The file wasn't uploaded in the previous post. Here's a link. Click on "Filters" for the PP file.

http://motion.kodak.com/US/en/motion/Education/Tools_for_Educators/index.htm

[Helen Bach]

If you don't use filters with colour neg film to correct colour temperature and tint mismatch then you need to make sure that none of the layers are underexposed - given that for colour neg film the box EI or ISO (or aim density speed) is based on what happens somewhere between the toe and the aim point for an 18% grey card rather than what happens up at the shoulder.

This means that, filterless, the greater the CCT+C/M mismatch the more exposure you need to give. Oddly enough the exposure will probably be the same as it would be if the correct CCT+C/M correction filter(s) was used (Because a filter cuts light, it doesn't add any). If you are working filterless, the greater the mismatch the greater the likelihood of one of the other layers moving too far up the curve - that's why a filter helps.

Use daylight film in incandescent light and you need to expose for the blue-sensitive layer. This risks overexposure of the red-sensitive layer if you don't use a filter. The red-sensitive layer may be exposed too high up on the curve, where it is no longer linear and parallel with the lower part of the blue-sensitive layer. Using an 80-series filter reduces the exposure of the red-sensitive layer and to a lesser extent the green-sensitive layer, thus making subsequent correction easier, especially if printing optically.

For colour neg film, because of its greater dynamic range, it's not critical to get the colour match anywhere near as perfect as it is for reversal, especially if you are doing digital post-processing. If you want to use all of the film's dynamic range you do need to get the colour match close, however (this describes my practice most of the time).

It's much simpler to envision than to explain.

Best,
Helen

[Drew Wiley]

I too must reinforce the axiom that certain color temp corrections must be made on
location. By the time you get to printing it's too late - there are certain ways the film
responds or overresponds and you have to account for this when shooting. I'm slowly going through a very refined series of tests with this new Ektar sheet film to determine
exactly where the parameters lie, but I am certain that I need a warming filter or two
in my travel kit. Skylight filters aren't the same thing - they might mildly warm, but are
otherwise for UV control, and to work properly must be engineered for specific types of
film (there are clear ones, slightly pink ones, slightly amber ones, etc), whereas filters
like 81A,81B etc are for basic color temp work and can be used with all types of color
film.

[Mark Woods]

Well Helen, you had to go there! ;-) The other issue is the lack of exposure of a color layer. When enlarged, this creates "noise" or excessive graininess. You can also get color shift. I've dealt with this in my day job as a cinematographer for 30 years. That's why I only shoot B&W. Besides, I like it better. ;-)

[SeanEsopenko]

I'm starting to kind of get this. So let me reword this and tell me if I'm comprehending it properly.


If you don't use filters with colour neg film to correct colour temperature and tint mismatch then you need to make sure that none of the layers are underexposed

This is because in negative film underexposed regions are "developed" away. You can't create information from nothing and this is why an underexposed layer causes colour correction issues. So I have to be critical with underexposure (same as B&W negative film) and for all 3 layers. Shadow area colour correction issues lie in one or more colour layers being underexposed.


Use daylight film in incandescent light and you need to expose for the blue-sensitive layer. This risks overexposure of the red-sensitive layer if you don't use a filter. The red-sensitive layer may be exposed too high up on the curve, where it is no longer linear and parallel with the lower part of the blue-sensitive layer. Using an 80-series filter reduces the exposure of the red-sensitive layer and to a lesser extent the green-sensitive layer, thus making subsequent correction easier, especially if printing optically.

As an example, incandescent light requires more exposure in the blue layer to compensate for the red hued light. An 80-series filter meant to colour correct this will have a sort of blue look to it when I look through it because it is lowering the light of the red and the green layers (similar to how a red filter for b&w is limiting the other colours of the spectrum). If a colour negative film had 10 stops (I don't know/remember exactly how much leeway colour negatives have), correcting the colour balance with filters ensures that each layer is properly exposed with shadow and hilight detail. It's like applying zone system exposure theory to 3 separate layers, maintaining detail in the shadows and hilights by ensuring I don't over/under expose any of the layers.


Skylight filters aren't the same thing - they might mildly warm, but are
otherwise for UV control, and to work properly must be engineered for specific types of
film (there are clear ones, slightly pink ones, slightly amber ones, etc), whereas filters
like 81A,81B etc are for basic color temp work and can be used with all types of color
film.

I was incorrect to assume a Skylight 1A is the same as an 81A filter and incorrect to assume a Skylight 1B is the same as an 81B filter.


If you want to use all of the film's dynamic range you do need to get the colour match close, however (this describes my practice most of the time).

Correct colour balancing will give me the most dynamic range I can get out of colour film from all 3 colour layers. Great, I think I understand the basics now :).

edit: as an addendum, digital cameras white balance automatically in the camera but you're theoretically losing dynamic range by doing this in post processing aren't you? (whether auto-balancing in camera, or with photoshop) If one were to colour correct digital shots with filters then there would be more information recorded with less overexposure/underexposure in each RGB channel. I have RGB levels turned on for the automatic preview of my 5D and I pay attention to any channels overexposing. I frequently see one channel shifted to the right/left of the others but if I used colour correcting filters I could try to wedge all the channels perfectly to the right where the most information is being recorded. White balancing digital pictures through software is just common laziness, isn't it? ;)

[Helen Bach]

I thought that it was worth 'going there' because I prefer to understand an issue than simply remember what I'm supposed to do (which I'm bad at because I'm so ditzy).

The part I mentioned about avoiding underexposure of a layer is indeed because of the increase in graininess at the toe end of the curve (particularly in the blue-sensitive layer, as it would happen), as well as the colour issue.

The part about layers being at different parts of their curves was about colour problems - once one layer is in a part of its curve that is not parallel to the part of the curve that another layer is in you start to have problems because of the differing contrasts between the layers. It can be handled digitally (albeit not straightforwardly) but is problematic (but not impossible) to handle traditionally. There are also the colour issues caused when one layer is so far underexposed that there is no image to be balanced up with the other layers, as you mention.

Sean, you seem to have pretty much got it.

Best,
Helen

By the way, the 80 and 85 series filters may correct to the right colorimeter-measured CCT but there is usually a mismatch in spectral distribution between, say, true 5500 K daylight and 3200 K studio incandescent corrected to 5500 K with a filter. It's not an exact science because of the non-ideal properties of the dyes used in the filters.

[D. Bryant]

which I'm bad at because I'm so ditzy.


Just an aside for those reading this thread, I want to express my admiration for the work that Helen does with large format color negative film.

She is an extremely knowledgeable photographer and I'm fortunate to own a couple of her prints made from large format color negatives. She really knows what she is talking about - take it to the bank as they say.

Helen you are anything but ditzy! :cool:

Don Bryant

[SeanEsopenko]

So I don't have the cash to purchase a colorimeter for a while. Does anybody have some advice on how to eyeball common colour temperature shifts when shooting outdoors and the filter required to correct it? Which filter would I use for tungsten lighting, which for fluorescent, too?

[atlcruiser]

thank you all and especially thanks to helen....i sort of understand this now :) maybe better to say I dont understand it less!

To echo what Sean mentioned above are there any "rules of thumb" with outdoor situations to help get me in the correct ballpark with the 81 series filters?

Also, suggesstions on a color meter?

[Mark Woods]

"White balancing digital pictures through software is just common laziness, isn't it?"
Yes.

If you go to the Kodak website and look at the CT of different times of day and the color of the sky, you will be huge steps ahead in correcting your film on set. Also, if the emulsions don't track parallel, then there is a color shift at that point of the exposure. (The color shift I mentioned previously.) Also, an 85 filter "only" corrects "daylight" to 3400*K (look it up). An 85B is the actual correction in "normal" circumstances. I find that either an 85B or an 85 coupled with an 85D is the correct filter pack for daylight to 3200*K. Finally, each electronic imager has an optimized CT that it responds to. When it's pushed to respond to other CTs, one has the same problems one has with Tungsten film not shot in a Tungsten environment.

Whew! I usually spend 3 weeks on this at AFI. There is also chromatic adaptation.... And others................

[tgtaylor]

I've learned to tread carefully when adding filters.

About ten years back I all but busted my rear end hiking out in the Sierra Nevada with a mid afternoon start to photograph Ritter and Banner Peak at daybreak from Thousand Lake. I arrived within striking distance shortly before dark and with an early morning start arrived on location in time to greet the sunrise.

Shooting both Fuji Velvia and Kodak color negative film with a Pentax 67II and being a novice, I foolishly placed an 81AorB filter on the lens and shot a roll of each. The slides turned out yucky but the prints from the negatives were spectacular: the lab had simply eliminated the filters color cast of when printing. I remember showing them to my sales manager at work and noticed him wince when looking at the slides but smiling and nodding when looking at the prints. If I hadn't used the filter the slides would look just as good as the prints.

Now that I am both developing and printing my films I realize that I can adjust colors in the printing process and seldom, if ever, use the 81 series of warming filters when shooting color negative films. I may not be entirely correct in this assessment but close I'm sure.

The best advice I can offer is to avoid using a filter unless it is absolutely necessary.

Thomas

[Mark Woods]

Thomas, I hate to be blunt. But did you know the CT of the shot when you shot it? Do you think that using a filter that apparently you have no idea how much it will shift the CT is the magic solution -- particularly in the situation you were in? And do you know that at sunrise and sunset the CT of the sun is about 2700*K. With daylight film, that's very warm and probably the "look" that you wanted. 2700* is even warm with Tungsten film. The latitude of the negative stock is well known, but the preciseness that one needs to expose chromes indicates the skill and knowledge of the photographer.

Have a good evening.

[atlcruiser]

mark,
I went to the link on Kodak and learned a lot! It is not nearly as complicated as I thought.

Correct me if I am wrong:
When shooting outdoors with clr neg film it is really up to what i want to see as to how I might filter. The base CT should be around 5500K as a benchmark with adjustments hotter/colder from there taking account sunlight vs skylight and what CT is the goal

Outdoors with clr reversal film it is a much bigger deal to get the correct CT so on can get even exposure throughout the range of the film. I looked back on a bunch of slides and saw the blue shadows :)

[tgtaylor]

Thomas, I hate to be blunt. But did you know the CT of the shot when you shot it? Do you think that using a filter that apparently you have no idea how much it will shift the CT is the magic solution -- particularly in the situation you were in? And do you know that at sunrise and sunset the CT of the sun is about 2700*K. With daylight film, that's very warm and probably the "look" that you wanted. 2700* is even warm with Tungsten film. The latitude of the negative stock is well known, but the preciseness that one needs to expose chromes indicates the skill and knowledge of the photographer.

Have a good evening.

That's precisely my point Mark. At the time I didn't really know how to use filters. Back then I, like a lot of photographers, routinely shot with a polarizer on the lens thinking that it would result in beautiful blue skies and pop the colors which, of course, it does do on the right occasion.

Now I'm wiser and prefer lighter blue skies and know that the polarizer will also extinguish the colors and only use the warming filters if I want to bring a harsh light down to a warmer realm or if shooting in an open shade. But I have stopped shooting transparencies and now shoot color negative so I don't have to reach for the warming filters as I would have to with chromes. You have far greater control and latitude when shooting color negative than you do when shooting transparencies. Note the Kodak's footnote "* For best results without special printing. taken from the date sheet on the new Porta 160 film:

Use the speed numbers in the tables below with cameras
or meters marked for ISO, ASA, or DIN speeds or exposure
indexes (EIs). Do not change the film-speed setting when
metering through a filter. Metering through filters may
affect light meter accuracy; see your meter or camera
manual for specific information. For critical work, make a
series of test exposures.

Light Source
KODAK
WRATTEN
Gelatin Filter*
ISO Speed
Daylight or Electronic Flash None 160
Photolamp (3400 K) No. 80B 50
Tungsten (3200 K) No. 80A 40
* For best results without special printing.

Thomas

[Mark Woods]

Hello Thomas, in motion picture work it's all color negative and I'm well acquainted with it. I understand the latitude, but to get the optimum image, one needs to make the optimum exposure and CT balance. BTW, polarizers will often make the colors more saturate since they can remove any reflection of light that will desaturate the color. They can also make the skin look unnatural since there won't be any sheen as we see every day. If you want to look at the basis of my approach here's a link I wrote for the Camera Guild (cameraman's local union LA Chapter):

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

Enjoy!

BTW, the "special printing" can cause you a world of hurt as Helen mentioned.

[Mark Woods]

Hello David, I'm happy I could help. The Kodak website is really a wealth of information.

[Drew Wiley]

If you want to get the most out of color neg film, expose it with as much care as a chrome. Winging the exposure of balance based on "latititude" simply results in some kind of compromise and not an optimization of what the film in engineered to do. If you can't afford to buy a color temp meter, rent or borrow one for a weekend and take a variety of typical readings. I particularly like the Minolta color meter. The learning curve with chrome film is obviously easier, not only because it is less forgiving
of carelessness, but because you can simply plop the result down on a lightbox and
evaluate what you got without having to print it.

[SeanEsopenko]

If you want to get the most out of color neg film, expose it with as much care as a chrome. Winging the exposure of balance based on "latititude" simply results in some kind of compromise and not an optimization of what the film in engineered to do. If you can't afford to buy a color temp meter, rent or borrow one for a weekend and take a variety of typical readings. I particularly like the Minolta color meter.

Yeah I got into the extra work/expense of large format photography to set myself apart from people who are shooting digitally. If there's something I can do, technique wise, to set myself apart even further, all the better :).

Seems like a Minolta Color Meter II can be had for about $300 on ebay. Much less than the $1000+ I saw for a color meter brand new from B&H. I should be able to outfit myself completely for shooting & printing colour negative film by the end of the year though, so it's all good.

I don't know anybody local to me who has a color meter I could borrow but I'll ask around.

[atlcruiser]

I dont want to hijack but......

What do i need to do when using a polorizing filter? If i am thinking about this correctly the P filter wont change the temp of the light but will it change how my CC filter reacts to the light?