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Education on film grading


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I am reading Dominic's book "Film Technology in Post Production" even as we speak. which has 2 sections on telecine grading, HOWEVER sense I'm not telecining but am going with work prints, I suspect to process of grading is somewhat different. I have not as yet picked up "Motion Picture Film Processing" though I intend to as soon as possible. It may have a section on grading in there. I'll check the links you guys provided, if you do have anything to add, particularly with regards to print grading, I would be most appreciative. thanks-The Captain B)

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Have you read Dominic Case's book?

 

Here is a discussion:

http://www.cinematography.net/Pages%20DW/F...FilmProcess.htm

 

I'm guessing pre-Hazeltine days, there must have been a lot of wedge testing / Cinex strips made...

 

There was a thread on Cinex strips within the past couple of years on here IIRC. Maybe that would help you pick up on the process.

 

Basically, it's almost like making workstrips in still photography. You figure out exposure first (after getting colors within the ballpark) and then figure out color. The key here is doing this quickly. You can waste a LOT of time bouncing back and forth from color to exposure. This is partly due to the non-linear regions of the film response curve. As you change exposure you get color shift. It used to be a lot worse, but despite what Kodak says, you still get it.

 

There's no where near as much art to this as people make out either, at least in my opinion. There's a little bit of wiggle room where you can make skin tones warmer than normal, but it is really more of a science.

 

Do yourself a huge favor: Shoot charts, shoot grey cards, do it with every emulsion, every change of locale and lighting. Balance the cards and charts and you are going to save yourself a huge amount of misery.

 

There's basically two systems of color control: additive and subtractive. Additive deals with three high-speed exposures with red, green, and blue light. Base exposure is controlled with red, again to make life easy and avoid color shifts with exposure changes to as great an extent as possible. Subtractive uses white light which is color-balanced through the use of cyan, yellow, and magenta filters, usually only involving yellow and magenta as cyan serves a similar purpose to red in additive and can be used for density control without having to worry about a change in exposure due to exposure time or F/stop change. Another favor you can do yourself is, if using subtractive color correction, to AVOID stacking CMY filters. Make sure you have a dichroic lamphouse or use additive, making sure your red, green, and blue filters haven't faded.

 

It is systematic, trial-and-error testing using a reference, like the original grey card and test charts under balanced lighting (not to bright or too dim, 5000K color temperature). Once you match your film to them as closely as possible, wasting as little print stock as possible, you have color-corrected the whole scene. There are probably people that are going to come in here and disagree with me on this, but I feel the only way you can keep skin tones constant throughout a film is to NOT color-balance with them.

 

Get those Kodak color viewing filter kits, they're helpful. When evaluating tests with them, remember to look at midtones not white or blacks because they show more color shift than is actually indicated on the filters. Get a film-strip projector, with a bulb of the same color temperature as you intend to use for projection (at least make sure it is close) for easier evaluation of cinex strips, a light box that is either color matched to your projector bulbs or to 5000K with fluorescent tubes, and figure out a way to make cinex strips if you haven't already done so. Make sure the frame you use for testing is representative of the shot as a whole and doesn't have anyone's cast shadow over it.

 

Hope this helps!

 

~KB

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One more thing, you're in the U.S. Call it by its proper name here, film TIMING, not like the damned Brits ;)

THe forum may run in the USA< but the poster is no doubt safely in the UK, that is the problem with international forums, everyone has to deal with teh differences in local usage of the english language. Timing is the US term, although Grading is perhaps more descriptive. As a Canadian I take whatever and adjust, just like I am not phased if someone says they needed a Lorry to carry all their camera gear.

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As timing harks back to timing in development I'd say "grading" is more acurate really. Plus I've seen 'grading' used by at least one US lab.

 

It could be argued it's all science but the best timers (graders ;-) seem to go at it with artistry. I think I said before here "the art of print timing consists of knowing just how misleading the Hazeltine IS.........."

 

 

I once saw Harry Kasper of Filmtronics Labs grade (see I'm trying to be sort of consistent <_< color neg by eye on a light table. Makes me think of Sid's agent (from "The Larry Sanders Show") "He wasn't Old School, he was the school they tore down to BUILD the Old School"

 

-Sam

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I am reading Dominic's book "Film Technology in Post Production" even as we speak. which has 2 sections on telecine grading, HOWEVER sense I'm not telecining but am going with work prints, I suspect to process of grading is somewhat different.

Pages 76 to 83 of the 2nd ed of "Film Technology in Post Production" deal with film grading. There is a bit more in "Motion Picture Film Processing" but it has been out of print for a few years so you will need to find a second-hand copy.

 

As James is in Texas, he could have been excused for calling the process "timing", but he chose not to. As I am in Australia where (like the Canadians) we tolerate a variety of languages, and my publisher is in Britain, I use the term "grading". In any case, both graders and timers tend increasingly to be called "colorists" these days - and as that is an American neologism I spell it thus, even though I inist on the original British "colour".

 

All that aside, grading for print is indeed different from telecine or digital colour correction. However, both are ESSENTIALLY "judgement rather than hard science". The object of the exercise is threefold

  • to correct for errors in exposure or filtering
  • to impose or restore colour continuity to a scene (or sequence of shots:in grading, each shot is called a "scene")
  • to add a mood or feeling to a scene

Print colour and density is controlled by the exposure to R, G & B light in the printing process. There are various ways of doing this, and various ways of determining what is correct (read the book or follow David's link earlier in this thread - or pursue this thread :blink: ). But essentially, all you can do is make the entire frame lighter, darker, or more or less red, green or blue. Of course in the days when cinematographers set everything up completely and correctly in front of the camera, that was all that was ever necessary - and with a good cinematographer, you could often print complete reels with almost no scene-to-scenbe corrections.

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Hey Dominic,

 

If James is going to time optically, won't he need some appropriate equipment? What's the name of the viewing table that colorists used along with the paper tape encoding machine? I've seen them used back in the good old days but never used one myself. You're the most likely help on equipment suggestions. He'll need something common enough that he can grab up for it's worth in metal weight off of Ebay or out of the back door of a downsizing lab.

 

James,

 

I do respect how you're staying loyal to an all optical post as well as doing it all in-house. BUT, I think life would be easier for you if you went DI.

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..............Of course in the days when cinematographers set everything up completely and correctly in front of the camera, that was all that was ever necessary - and with a good cinematographer, you could often print complete reels with almost no scene-to-scene corrections.

The old timers came up through a system where everyone knew their craft inside and out. In this "We'll fix in post" era with know nothings running around with video cameras nothing looks good. I'm thinking of forming a Natalie Kalmus appreciation society. Everyone who worked a film she was on apparently hated her - but the films looked good.

 

http://www.imdb.com/name/nm0436124/

 

http://en.wikipedia.org/wiki/Natalie_Kalmus

 

kalmus.jpg

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James, just send the negative out to be printed. It's time to stop building a lab and start shooting your movie after all these years!

 

You get into printing and now you're talking about a separate ECP line of developer tanks, you're talking about a Hazeltine, some sort of paper tape system to record printer light information, a contact printer, etc. And I doubt you'll do enough print processing to justify the costs of replenishing the chemicals to keep them fresh.

 

Not to mention the knowledge to use all of this equipment properly. Lab work is a highly specialized skill.

 

This is rather like building a car for four years just to take a trip to the grocery store...

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James,

 

I'm sorry, but, I have to agree with David. I'm afraid you'll get pulled under and drowned by the weight of the complex machinery it takes to create an all optical post house. I'd rather see your motion picture creativity than your technical achievement. One computer replaces a half dozen to a dozen pieces of optical post equipment. You can still be in control without having to prop up a pile of antiquated machines.

 

We only say this because we care enough about you to say it.

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To weigh in on this as someone who has attempted the very difficult task of doing the same thing in still photography, I'd recommend that, if you want to cut costs, you stick with one aspect, say printing. You can't develop negatives, develop prints, edit, color-time, soundtrack-stripe all on your own. That's insane.

 

Even well-staffed labs of several dozen or more people often only specialize in say, negative development, or telecine.

 

If there is something that isn't being offered (in still photography, it is difficult or impossible now to find labs that print and finish optically, which prompted some of my DIY printing in the first place), then I can see you setting up equipment to do that particular aspect of film finishing yourself, but all of these services are CURRENTLY offered, and in abundance very near your viscinity.

 

You could probably drive to some of the labs nearest you. No need to reinvent the wheel here!

 

And to all Australians, Canadians, and British members of this forum, I really was just joking about timing vs. grading, as he's from Texas, still apart of the Union last I checked. I agree that the later term is more accurate. Remember, I'm the guy in the U.S. that spells "grey" with an E! Standardization is boring anyway.

Edited by Karl Borowski
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James, just send the negative out to be printed. It's time to stop building a lab and start shooting your movie after all these years!

 

You can't develop negatives, develop prints, edit, color-time, soundtrack-stripe all on your own. That's insane.
David, Paul and Karl - you are probably right - if James is simply setting out to make a movie in the way most people do. But he's come this far, so I guess his intention is to make the damn film from start to finish.

 

Your argument is the same is saying "why go fishing when you can buy a fish from the supermarket?"

 

Where are your souls?

 

Mind you, having spent my life working in the business of developing and printing (and now scanning and so on), I have to agree that he probably is insane to want to do it himself. And we are all the richer on this list for that.

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.............."why go fishing when you can buy a fish from the supermarket?"

 

Where are your souls?

 

Mind you, having spent my life working in the business of developing and printing (and now scanning and so on), I have to agree that he probably is insane to want to do it himself. And we are all the richer on this list for that.

So what would be the best recommendation overall? IE: Which pieces of the puzzle are probably achievable by a solo combat warrior, and which are best left to labs? I personally would have my camera negative developed professionally. That's the one step that if it isn't right screws up everything subsequent. You can always reprint, regrade, etc., etc. but if your negatives poop, you're screwed.

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Well, I've already dug the hole, I just need to fill it up with water and throw in the fish. :D The film will be shot this year, I am in the process of gathering up and saving all the cash I can to pay everyone for production. I plan to shoot maybe November, December for 2 to 3 weeks with 16 hour days, grueling schedule but I've ran the numbers and it's doable. I consider the actual production, post production and sale the final step, in this odyssey I'm on here. The equipment I have isn't all that antiquated, Brey still makes that particular model of film processor and I have a contact printer, it came with the processing machine along with a massive amount of chemicals.

 

There's a few small, nickel and dime things I have to get, but the major purchases have already been done, and at a very, very reasonable price I might add, let me put it this way, my TOTAL investment wouldn't pay for half the cost of a digital to 35mm transfer. We're not gonna get fancy with processing, MAYBE a one stop push at most and that's only because I'm using these older slower anamorphics, (I'd be smarter to use my fast sphericals, but I really want to use all that negative space in my composition.) The replenishing isn't really all that big of an issue, the tanks on the machine are tiny, it was built for small runs of film, they're maybe a gallon each if that. Maybe I'll hire some chemistry grad students from the university who are use to working with chemicals to run the lab while I'm shooting. I'm also gonna try and follow Domiinic's advice and keep color correction to a minimum by again going old school and returning to the days when cinematographers set everything up completely and correctly in front of the camera, so that's all that is necessary and we don't have to correct every single scene.

 

The whole point of doing this this way is that once the support facilities are in place, we can shoot several films. I don't have to shop scripts around, HOPE someone can see my vision, try and live with the micro management of a studio or producer. I green-lite my films, I control their look, I make the profits or live with the losses. I very much respect you, Dave and DO listen to everything you say. I plan on shooting some MOS and second unit stuff first with a small crew if any, processing the footage and printing it. If it looks real bad, I'll try and correct the problems. If I can't, I'll look into alternatives, but I wanna try this. Cool? B)

 

Oh, and I might add, I never built a car fram scratch to go to the store but when I wanted to go autocross and drag racing, I did, 'course now if gas prices keep going up who knows, I got a bunch of electric golf carts out back of the studio....:D

Edited by James Steven Beverly
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One more thing, you're in the U.S. Call it by its proper name here, film TIMING, not like the damned Brits ;)

 

I've been taught to give both names to separate aspects of color correction.

 

Film Timing: Refers to color correction to a print

 

Film Grading: Refers to DI or Telecine color correction.

 

Of course, with the advent of DI to a film out, the line is a bit blurred. Grading is of course more accurate. With the original term "timing" referring only to the amount of time a negative/print is left in the developer.

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Of course, with the advent of DI to a film out, the line is a bit blurred. Grading is of course more accurate. With the original term "timing" referring only to the amount of time a negative/print is left in the developer.

I have to disagree with this. Scene-to-scene density or colour correction cannot be acheived by leaving the film in the developer for different times. It's physically impossible to vary the running speed of the machine to suit different scenes, and in any case, it's not the right way to control density or colour.

 

Continuous contact printing machines from the 1920s on have all used a device called a light valve to control the exposure on the print. Early B&H model D printers and the like were for black and white. The "valve" was a pair of blades placed in the light path in the printer, that opened or closed automatically to different widths for different "lights". A bit like barn doors, they controlled the width of the light beam that was focussed on the slit-shaped aperture that the neg and print travel past. A wider slit results in a longer exposure time in the light beam. So in fact, print exposure is varied by time.

 

Some subtractive colour printers worked slightly differently, with filters: but modern printing machines are all direct descendants of the 1960s Model C printers, which use the same light valve principle in a dichroic light box that separates, controls and then recombines the three additive colours red, green and blue.

 

Although the original timing scale was in printer points, not fractions of a second, it is still a time variation. Hence the term "timing".

 

I always figured that "grading" was like road grading - that is, evening out the bumps.

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Timing seems more accurate to me, because early color systems actually made three separate exposures through red, green, and blue filters, so you had to "time" each exposure with each color.

 

I'm pretty sure the term has nothing to do with development whatsoever. Back in the B&W days, they fine-tuned the developer to achieve a certain gamma for middle grey on the negative (at least so I've heard as I obviously wasn't around in the '50s), but I'm pretty sure that wasn't done for print stock, or was involved at all with the timing department.

 

Dominic: so none of the current optical or contact printers use CMY filtration anymore? Why did RGB take over? It's still a mix of both in the still photography world, although machinery tends to favor RGB and hand enlargers tend to favor CMY filtration almost exclusively.

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It's physically impossible to vary the running speed of the machine to suit different scenes

 

Which is part of my point. Timing is a name that actually pre-dates streamlined motion picture film processing. When a lab tech would literally stand by looking at his watch as the film was in the developer. So technically, the term timing (only considering its root meaning) probably has no place in describing modern color correction practices. Discuss :)

 

At least, that's the tale a prominent ACVL member told me once.

Edited by Jonathan Bowerbank
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Which is part of my point. Timing is a name that actually pre-dates streamlined motion picture film processing. When a lab tech would literally stand by looking at his watch as the film was in the developer. So technically, the term timing (only considering its root meaning) probably has no place in describing modern color correction practices. Discuss :)

 

At least, that's the tale a prominent ACVL member told me once.

 

So it was "timing" as in "developing by inspection". If so, then than makes sense to me. However, the term is, in my opinion, just as relavent then as it is today (at least photo-optically) in that you still have to vary the "times" of each of the three primary color exposures.

 

Even if the thing being timed is different, there is still that aspect involved. I still don't exactly know what is meant by grading; Dominic Case's explanation probably isn't how the term is derived.

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