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Neg Kodak 5201 -> Pos Kodak 2383


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#1 Evangelos Achillopoulos

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Posted 06 November 2006 - 05:29 PM

Hello from Greece

One simple question

Step 1. We take a negative stock Kodak 5201 50D Vision 2 and in total darkness we cut a piece of few feet?s. Without any exposure we send it to a lab that is honoured with the Kodak Imagecare Logo (following Kodak standards using Kodak Kit chemicals).
Step 2. We develop it.
Step 3. We measure the densities with an X-Rite densitometer and we finding it around 0.23~0.25.
Step 4. We are printing, from that negative, a positive in Kodak 2383 print stock according to the Kodak standards ECP-2D process (Same Lab, using analogue LAD the brunette lady) in 25, 25, 25 in printer lights.

So we have a print with total Black?

And the question is:

What are the expected densities of the black in the 2383? (using the particular neg stock 5201)

If someone from Kodak can give a straight answer with numbers it will be much helpful

Regards to everyone from Greece
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#2 John Pytlak RIP

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Posted 07 November 2006 - 06:40 PM

Hello from Greece

One simple question

Step 1. We take a negative stock Kodak 5201 50D Vision 2 and in total darkness we cut a piece of few feet?s. Without any exposure we send it to a lab that is honoured with the Kodak Imagecare Logo (following Kodak standards using Kodak Kit chemicals).
Step 2. We develop it.
Step 3. We measure the densities with an X-Rite densitometer and we finding it around 0.23~0.25.
Step 4. We are printing, from that negative, a positive in Kodak 2383 print stock according to the Kodak standards ECP-2D process (Same Lab, using analogue LAD the brunette lady) in 25, 25, 25 in printer lights.

So we have a print with total Black?

And the question is:

What are the expected densities of the black in the 2383? (using the particular neg stock 5201)

If someone from Kodak can give a straight answer with numbers it will be much helpful

Regards to everyone from Greece



Here is the typical sensitometry of the 5201:

http://www.kodak.com...mp;lc=en#graphs

http://www.kodak.com...on/curveBtn.gif

You normally would color time (grade) your processed negative relative to the LAD Control Film, rather than just print it at the setup balance of 25-25-25. But for a well exposed negative timed relative to LAD, you should expect a neutral black on the print, with Status A densities in the range of 3.0 or greater. As you increase negative exposure, you get a denser negative, and so increase printer exposure, giving even more dense "richer" blacks.

Here is more information about how labs use LAD, which I developed:

http://www.kodak.com.../...5.8.6&lc=en

http://www.film-tech...e...&category=3
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#3 Evangelos Achillopoulos

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Posted 08 November 2006 - 08:05 AM

Dear Mr. Pytlak

It?s my pleasure to chat with you about my problem.

My referral to ?(Same Lab, using analogue LAD the brunette lady)? is going to your ?LAD for KODAK VISION Color Print Film? or ?LAD Control Film?.

When we do DI and we film out the result, we want to have the best black level (density) in our positive 2383 without having to push the color timing in the printer side, because this will affect the white level. Someone will say that we have to grade in a way that when we going to the positive printer to increase the exposure in order to have more dense blacks. But this is wrong because then we going to loose all the highlights.

Moreover DI process is not involving a natural exposed film instead the exposure is being done by the laser or the CRT of a film printer and it?s already using the maximum latitude of the negative. In a proof of that, if we measure the black and the white on the printed negative we get the D-Min and the D-Max of the negative so there is no room for ?As you increase negative exposure, you get a denser negative,?.

I want to understand what the tolerances of the normal black print are in order to evaluate the quality of the LAB that am dealing with.

In my personal opinion along with some other DP that they see the result they say positive Visual density below 3.4 can be evaluated as ?milky black? so I want to understand if your answer, that anything above 3 is good has an artistic tolerance influence. To clarify artistic means: A romantic film will need softer blacks than an action film.

My definition of black is that when its projected inside the theatre should be like the lamp of the projector is OFF and no light is passing to the screen or the black on the middle of the screen must mach the black of the border of the screen as projected.

More over a pre exposed 2383 test strip has a black visual density of 3.64 in that particular Lab and our negative print gives when printed in a positive 2383 gives 3.22.

So what is the range of the black densities with no artistic tolerances?
Shouldn?t has to much the test strip?
Is their any white paper that deals with the tolerances?
What is the experience of other forum members on that subject?

Best regards,
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#4 John Pytlak RIP

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Posted 08 November 2006 - 02:16 PM

When using a DI, the final images may not seem to have as much "snap", or have a truly opaque black in the final prints, mostly due to flare in the optical system of the CRT film recorder. Some have found the easy (but slightly more costly) solution is to use Kodak VISION Premier Color Print Film 2393 for the prints.

5201 should have more than sufficient latitude to capture all the image detail that will end up in the final print. If your DI is correctly exposed, the blackest black in the scene will be just visible above the D-Min on the processed negative, and the brightest highlights should still not reach the D-Max that 5201 is capable of. When you consider the flare of the CRT recording system, you certainly will not exceed the straight line portion of a high latitude film like 5201.
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#5 Evangelos Achillopoulos

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Posted 08 November 2006 - 06:57 PM

When using a DI, the final images may not seem to have as much "snap", or have a truly opaque black in the final prints, mostly due to flare in the optical system of the CRT film recorder. Some have found the easy (but slightly more costly) solution is to use Kodak VISION Premier Color Print Film 2393 for the prints.

5201 should have more than sufficient latitude to capture all the image detail that will end up in the final print. If your DI is correctly exposed, the blackest black in the scene will be just visible above the D-Min on the processed negative, and the brightest highlights should still not reach the D-Max that 5201 is capable of. When you consider the flare of the CRT recording system, you certainly will not exceed the straight line portion of a high latitude film like 5201.


Dear Mr. Pytlak

I read another post and I realised your medical situation and I have been shocked. Am sympathizing you and my honest wishes to overcome that evil. Just be strong and see the example of cyclist Armstrong and what he has achieved.

Now to the subject of this post ?Step 1. We take a negative stock Kodak 5201 50D Vision 2 and in total darkness we cut a piece of few feet?s. Without any exposure we send it to a lab? so there is no CRT printing involved so NO flare issues in my test ?

My questions are still UNANSWERED:

?More over a pre exposed 2383 Kodak test strip has a black visual density of 3.64 in that particular Lab and our negative print gives when printed in a positive 2383 gives 3.22.?

There is a clear difference of a 0.42 Visual density.

So what we have to do to reach the 3.64 visual densities in normal LAD conditions?
And what are the expected densities of the above example (original post)?
Is their any spec sheet that states the tolerances of the expected densities in order to evaluate the quality of printing of a Lab?

So please someone from Kodak give an answer to the above questions or explain me why I can?t have an answer.

Thanks in advance
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#6 John Pytlak RIP

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Posted 09 November 2006 - 09:47 AM

?More over a pre exposed 2383 Kodak test strip has a black visual density of 3.64 in that particular Lab and our negative print gives when printed in a positive 2383 gives 3.22.?

There is a clear difference of a 0.42 Visual density.


You should not expect the black densities in your print to reach the D-Max the print film is capable of. A black density of 3.22 on 2383 is within the range that might be expected for a normal negative. Although not completely opaque, it only lets less than 1/1000 of the light through the print. If you want a "blacker" black, you can try increasing the exposure of the DI, so that it prints at higher printer lights. Or you can print onto 2393, which has higher upper scale contrast and a much higher D-Max.
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#7 Evangelos Achillopoulos

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Posted 09 November 2006 - 10:07 AM

You should not expect the black densities in your print to reach the D-Max the print film is capable of. A black density of 3.22 on 2383 is within the range that might be expected for a normal negative. Although not completely opaque, it only lets less than 1/1000 of the light through the print. If you want a "blacker" black, you can try increasing the exposure of the DI, so that it prints at higher printer lights. Or you can print onto 2393, which has higher upper scale contrast and a much higher D-Max.


Hello

If the 3.22 is producing less than 1/1000 then it?s not correct according to the film projection standards.

But 3.22 how is it translated in contrast 1/900, 1/800? Or less?

Thanks in advance John.

PS. Rising Sun Research found that from a database of profiled positives from Kodak (films samples that are coming from around the world) the average Visual black density for the 2383 is between 3,5- 4.0.
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#8 John Pytlak RIP

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Posted 09 November 2006 - 10:35 PM

Hello

If the 3.22 is producing less than 1/1000 then it?s not correct according to the film projection standards.

But 3.22 how is it translated in contrast 1/900, 1/800? Or less?

Thanks in advance John.

PS. Rising Sun Research found that from a database of profiled positives from Kodak (films samples that are coming from around the world) the average Visual black density for the 2383 is between 3,5- 4.0.


Actually, a density of 3.22 lets only 1/1660 of the light though -- which is quite black. I suspect the survey you cite includes camera original, and not only DI. A normal or overexposed camera original will usually produce somewhat higher black densities than a print made from DI from the same original, due to the slight flare inherent in the DI process.
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#9 Evangelos Achillopoulos

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Posted 06 April 2007 - 09:19 AM

The answer to the original question is:

3.25 to 3.3 visual densities

If the film printing is being pushed by 2 stops the numbers should be around 3.4 ? 3.5
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#10 K Borowski

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Posted 08 April 2007 - 07:32 AM

Hi Evangelos: I wish that the labs that make the internegatives and release prints of films were as attentive to detail as it appears you are. Lately I've been shocked seeing things like large color shifts from one reel to the next, let along exposure or contrast consistancy. You have to understand, first of all, that even a CRT can't give you the full dynamic range that you would get with optical exposure. You're basically limited by the CRT in this case. There are ways of artificially pumping up contrast, as John suggests for instance with printing into Vision Premiere, but simple things such as light scatter (similar to what you'd get by doing an optical blowup or reduction) are going to compromise your ability to get the maximal theoretical density out of the film. You are going to get some "bleed" of light from highlight areas into the shadows, which will reduce contrast, although what you describe seems to be a lack of maximal exposure on the film, suggesting underexposure, most likely. It seems you do your own developing too. A less likely scenario is that your development temperature is too low or your developer times are too short to achieve that fullest density on the negative.

Also, I think part of your confusion stems from the way a log scale works. It is actually quite simple. Basically, the log numbers used in many of Kodak and other film manufacturer's characteristic curve charts represent an exponent, in this case, of the number ten. Therefore, Log 1 would be a 10:1 density, Log 2 would correspond to 100:1, Log 3: 1,000:1, and Log 4 would be 10,000:1. You'd need a calculator, or a Kodak Representative to determine non-integer logs though ;-) Remember that even a camera negative loses some of the detail in the highlights or the shadows, depending on timing, when it's printed onto IP film in conventional contact printing, so you aren't really being fair to your film recorder expecting it to transfer all of the gamma from the digital file to the film, especially as the file may not have the full level of the original scanned negative or HD camera to begin with.

Happy Easter,

~KB
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#11 Evangelos Achillopoulos

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Posted 08 April 2007 - 11:03 AM

Hi Evangelos: I wish that the labs that make the internegatives and release prints of films were as attentive to detail as it appears you are. Lately I've been shocked seeing things like large color shifts from one reel to the next, let along exposure or contrast consistancy. You have to understand, first of all, that even a CRT can't give you the full dynamic range that you would get with optical exposure. You're basically limited by the CRT in this case. There are ways of artificially pumping up contrast, as John suggests for instance with printing into Vision Premiere, but simple things such as light scatter (similar to what you'd get by doing an optical blowup or reduction) are going to compromise your ability to get the maximal theoretical density out of the film. You are going to get some "bleed" of light from highlight areas into the shadows, which will reduce contrast, although what you describe seems to be a lack of maximal exposure on the film, suggesting underexposure, most likely. It seems you do your own developing too. A less likely scenario is that your development temperature is too low or your developer times are too short to achieve that fullest density on the negative.

Also, I think part of your confusion stems from the way a log scale works. It is actually quite simple. Basically, the log numbers used in many of Kodak and other film manufacturer's characteristic curve charts represent an exponent, in this case, of the number ten. Therefore, Log 1 would be a 10:1 density, Log 2 would correspond to 100:1, Log 3: 1,000:1, and Log 4 would be 10,000:1. You'd need a calculator, or a Kodak Representative to determine non-integer logs though ;-) Remember that even a camera negative loses some of the detail in the highlights or the shadows, depending on timing, when it's printed onto IP film in conventional contact printing, so you aren't really being fair to your film recorder expecting it to transfer all of the gamma from the digital file to the film, especially as the file may not have the full level of the original scanned negative or HD camera to begin with.

Happy Easter,

~KB

Karl thanks for your effort to assist me. We are simple try to squeze to maximum the tools we have...

Please read the post from start and you will realize that am not developing films and am not expose any the question is very simple you can try it in your labs and tell me your findings.

We use Cinespace for viewing that has a correction to the latitude issue but in general you are right. Find their web site read about them a bit its very interesting.

You can keep my follow up as its being concluded together with Kodak R&D in France.

My problem was that when we print to Camera negative we can?t push the neg by two stops while we expose it in a film printer in order to get richer blacks in positive.

I realize that this is a trick that?s can be done only with inter negative because it can reach higher densities.

Happy Easter to you also
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#12 K Borowski

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Posted 09 April 2007 - 02:52 PM

My apollogies, I think this is a bit of a language-barrier issue. When you say "we push the negative two stops" and "we develop the negative" and "we print the negative. . ." I assumed that meant you were doingn each of these things in-house, as in you were exposing, processing, printing and processing again all on-site.

I think that you'd be best off talking to Dominic Case on this. He runs a cine lab. I only know what you're talking about because I develop my own color negative films for the still photography I do, and I run control strips and the terms and measurements used are all the same (for the most part).

By saying you are unable to push two stops, do you mean "increase exposure 2 stops"? A "PUSH" in English, at least that of the American variety, is what happens when you eitehr increase the length of time that the film is in the developer solution, you increase the temperature of the developer solution, or you increase the concentration of developingn chemicals in the developer solution to deepen the blacks of the negative by developing the silver halides longer, beyond what they'd be developed to in a development process that is run to Kodak's standard specifications. This confused me before anyway, because, while push processing could theoretically increase d-max in some cases, the increase that pushing would cause in the base fog, the "D-MIN" would often nullify the benefit due to any increase in d-max.

In any case, it sounds to me like you mean more that you can't increase your exposure, i.e. the intensity or duration of the light source necessary to obtain maximum density on the negative. I'd recommend that you try to find a dictionary of technical translations between (Greek?) and English. A lot of times there are a lot of differences between the lay meaning of a word and its technical meaning when you're translating between one language and another. Even between different flavors of English, such as Native English and American English we would say "push" and "time" and "black & white" in the United States whereas in the UK they would say instead "force", "grade" and "monochrome" instead.

If you intensity of CRT exposure, and also cannot increase or modify development, then I don't knw if there would be any solution to your problem, other than printing onto the more contrasty Vision Premiere, as Mr. Pytlak suggests.

I'm sorry, I really don't' know if it is possible to modify the intensity of a CRT. I've actually studied the principals of one of these, and you're dealing with an electron gun. You'd need to increase the intensity of the electron fields generated to increase exposure anymore, which would probably mean increasing voltage or current. Of course you cannot safely increase either of these if the CRT isn't designed for it.

Of course, I completely understand your wanting to get the best possible image from your workflow. I feel the same way. But if the first step in your image workflow chain is strained to your maximum potential, there really isn't any way to fix it unless you somehow can directly improve the intensity of the CRT.

I'll make sure Mr. Case gets a link to this thread. He may be able to help you further.

Regards,

~Karl
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#13 Evangelos Achillopoulos

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Posted 09 April 2007 - 03:45 PM

Yes Karl you are right the language burier can make thinks difficult.

Your guess was right the trick is to overexpose the internegative by 2 stops equivalent of 8 printer lights (push the highlights area higher in the exposure curve) in order when you printing the positive to under exposure by 8 printer lights in order to have denser blacks. This is a common trick that printing houses do, that I wasn?t aware of by that time?

Now I know and I understand that camera negative doesn?t allow this only internegative film because of the extended latitude.

But in general, the numbers for the above question is been posted.

And don?t forget that the question/experiment didn?t involve ANY exposure at all. I?m asking to actually cut a piece of unexposed film (in the dark room), develop it and then print it (normally no change in the printer lights) and measure the visual density of the black in positive. That?s all so NO CRT, NO EXPOSURE a simple experiment in order to be able to judge the numbers that am getting here.

Even thought what generated the question was all about exposure and latitude...

Thanks for your time.

Regards,
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#14 Sam Wells

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Posted 09 April 2007 - 03:47 PM

I still don't understand why you woud seem to prefer to pushing 2383 as opposed to printing on 2393/Premiere.

The perceived quality of a "black" is not neccesarily the same thing as D-max, perceptually this will be determined by the lighter things - especially highlights - surrounding it and in the frame.

-Sam
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#15 Dominic Case

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Posted 09 April 2007 - 07:42 PM

I've just looked through this thread, and I'm trying to dig right down to find the answer that Evangolos is looking for.

If I'm right, the original question boiled down to this:-

The maximum black on Kodak print stock 2383 is around 3.64.
The maximum print-through density from your 5201 negative exposed in a CRT recorder is 3.20.
You are looking for the missing 0.44 density, in order to get the blackest blacks possible on the cinema screen, without losing the whites.

I think that what you are hitting is the limitations of the entire system. Here are a few points - some of them have been raised already in this thread.
  • Don't expect to use the entire density range of the print stock in your image. Rght up at the D-max end you are on the shoulder of the characteristic curve, where you get little or no tone separation in your image.
  • So anything much above 3.20 or 3.30 would be crushed black anyway.
  • As has been stated, 3.20 represents about 1/1,600th of the intensity of light coming from the projector.
  • Most cinema screens don't get much darker than that because unwanted light from the brighter areas of the screen reflects around the auditorium and back onto the screen.
  • That said, 2393 Premiere stock does go blacker, and it has higher contrast: dark scenes with only a bit of bright area do benefit a certain amount - but I believe that is because of the higher contrast (gamma) together with the higher D-max black level.
  • In summary, your definition of black - "like when the projector lamp is off" is not practically possible. Your other reference - it must match the black border of the screen - is a good one, but it's not always possible to get that black.
  • Now, you say the density that you have obtained comes from printing at lights 25-25-25 . That may (or may not) be the light that your lab uses to print a LAD negative. It may (or may not) be the best light to print well-exposed camera negative. That doesn't make it the best light to print a well-exposed digital negative from a CRT film recorder.
  • If you want blacker blacks, you can get them by printing at a heavier printer light (4 or 5 lights would get you about 0.20 to 0.30 increased print density near the shoulder of the print curve).
  • As you say, you would need to increase the exposure in the CRT recorder to compensate for that (and keep the print whites white), and as a result you would get some density in the d-min area of the negative. This would lighten the blacks again.
  • The end result of this would probably be little or no gain in the black density, but a loss of resolution - as a brighter spot on the CRT would flare a little bit more.
  • As you have concluded, this is the limitation of using camera negative in a CRT film recorder. Because intermediate negative 2244 has a higher gamma (and finer grain!) it can give you a wider range of densities on the negative and therefore on the print. But it's too slow for most CRT recorders.
  • Summarising your final point - (which was the original question): what should be the density of black on a print-through from clear unexposed 5201 negative - the answer depends entirely on the printer lights that are used: and as explained above, the correct printer light for a digital negative depends on the properties of the film recorder.
If your real purpose (as you say) is to evaluate the LAB that you are using, then I'd say that if it is a Kodak Imagecare lab then you should have full confidence in the quality of processing - to correct Kodak standards. However, Imagecare doesn't measure the quality of the working relationship between the lab and whoever operates a film recorder. You must be the best judge of that: it is the relationship that is ABSOLUTELY VITAL to the successful use of a film recorder.
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#16 Evangelos Achillopoulos

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Posted 10 April 2007 - 10:26 AM

First of all thanks Karl for asking Dominic to assist me.

Sam I?m trying to reach the limits of 2383 and then, if I reach them, I will try the 2393 which I all ready know that it will work. But have in mind that it?s not the result that matters only, is also the knowledge that am trying to get out of all that. I understand your point the answer is following.

Dominic thanks for your assistance I understood everything very well. It?s obvious that I?m already using this new knowledge on things that am printing already.

Our company Motion FX is a rental house for Digital Cinematography (a Varicam system) and a DI lab for 2K/HD work. We using RSR Cinespace for color management, Final Touch 2K and a lasergraphics printer, we outsource the scanning in Hungary to a Northlight scanner. We outsource the film process to the Kodak Cinelab?s Greece. One of our works went last year to Cannes in the ?semain de la Critique? the feature was the ?Soul Kicking? of Yiannis Ikonomidis.

The whole problem started after CRT printing to negatives, developing and printing positives of 8 features successfully (with the same lab) the last 24 months with everything very well, blacks, whites etc.

Until the 9th feature which suddenly the Kodak Cinelabs Greece prints a positive (zero copy as a confidence test for the DoP) for the first act and the image was having milky blacks? No contrast, very bad?

Immediately everyone blame the DI process? and forced DoP to give me a direct order to add contrast from the printer software. I was against all this and I didn?t want to do it, I was telling them that something went wrong in the lab but they didn?t listen and I been forced to do it.

Because we didn?t have the time to reprint (with the added contrast) the first act of the film due to a deadline for the Thessalonica International Film Festival we left it as is end we continued to print (CRT printing with Lasergraphics Producer) the rest of the acts 2,3,4,5. The DoP changed the Lab and went to another Lab (that didn?t follow the Imagecare practice) in order to do the Zero copy.

So he reprints the first act from the ?bad? negative and WOW the image was stunning!!! He calls me in my mobile while he was in the projection room?

But on a different Lab?

As you can understand all the other acts were awful, crushed blacks and crushed whites?

Something happened that day in the Kodak Lab that didn?t happen again from that day. I have developed and print 5 more features with no problem at all at the Kodak Lab without doing anything different from our side.

Of coarse Kodak never accepted responsibility and I been left with a client feeling vary bad knowing that all this wasn?t our fault. And he knows that Kodak ruing his work? So the least that I can do is to check what happen that day.

During my quest I realize that the tolerances for the positive prints are tremendous they reaching the 0.30 D (therefore almost 9% of the total latitude of 3,5D for 2383) error before an alarm ring. Even though for negatives is as low as 0.02 D (1,3% of the 1,55 D for the 5201). So for Kodak being at the ? 0.23D that day in density at the control strips was OK?

The acceptable tolerances are an issue that someone has to address someday, because in the digital era we are measuring everything and we pushing everything to the limits so tolerances like that are unacceptable, while all the rest (DI houses, Post production houses etc.) we trying to minimize them? even eliminate them.

Regards,

PS. Just for the history we actually film print a LAD to the 5201 and then we skip frames unexposed so the printer lights are set to that LAD which is almost identical with the brunette lady LAD. So there is no problem to adjust the printer lights? and measure the black at the skipped frames area.
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#17 K Borowski

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Posted 10 April 2007 - 03:41 PM

First of all thanks Karl for asking Dominic to assist me.

Sam I?m trying to reach the limits of 2383 and then, if I reach them, I will try the 2393 which I all ready know that it will work. But have in mind that it?s not the result that matters only, is also the knowledge that am trying to get out of all that. I understand your point the answer is following.

Dominic thanks for your assistance I understood everything very well. It?s obvious that I?m already using this new knowledge on things that am printing already.

Our company Motion FX is a rental house for Digital Cinematography (a Varicam system) and a DI lab for 2K/HD work. We using RSR Cinespace for color management, Final Touch 2K and a lasergraphics printer, we outsource the scanning in Hungary to a Northlight scanner. We outsource the film process to the Kodak Cinelab?s Greece. One of our works went last year to Cannes in the ?semain de la Critique? the feature was the ?Soul Kicking? of Yiannis Ikonomidis.

The whole problem started after CRT printing to negatives, developing and printing positives of 8 features successfully (with the same lab) the last 24 months with everything very well, blacks, whites etc.

Until the 9th feature which suddenly the Kodak Cinelabs Greece prints a positive (zero copy as a confidence test for the DoP) for the first act and the image was having milky blacks? No contrast, very bad?

Immediately everyone blame the DI process? and forced DoP to give me a direct order to add contrast from the printer software. I was against all this and I didn?t want to do it, I was telling them that something went wrong in the lab but they didn?t listen and I been forced to do it.

Because we didn?t have the time to reprint (with the added contrast) the first act of the film due to a deadline for the Thessalonica International Film Festival we left it as is end we continued to print (CRT printing with Lasergraphics Producer) the rest of the acts 2,3,4,5. The DoP changed the Lab and went to another Lab (that didn?t follow the Imagecare practice) in order to do the Zero copy.

So he reprints the first act from the ?bad? negative and WOW the image was stunning!!! He calls me in my mobile while he was in the projection room?

But on a different Lab?

As you can understand all the other acts were awful, crushed blacks and crushed whites?

Something happened that day in the Kodak Lab that didn?t happen again from that day. I have developed and print 5 more features with no problem at all at the Kodak Lab without doing anything different from our side.

Of coarse Kodak never accepted responsibility and I been left with a client feeling vary bad knowing that all this wasn?t our fault. And he knows that Kodak ruing his work? So the least that I can do is to check what happen that day.

During my quest I realize that the tolerances for the positive prints are tremendous they reaching the 0.30 D (therefore almost 9% of the total latitude of 3,5D for 2383) error before an alarm ring. Even though for negatives is as low as 0.02 D (1,3% of the 1,55 D for the 5201). So for Kodak being at the ? 0.23D that day in density at the control strips was OK?

The acceptable tolerances are an issue that someone has to address someday, because in the digital era we are measuring everything and we pushing everything to the limits so tolerances like that are unacceptable, while all the rest (DI houses, Post production houses etc.) we trying to minimize them? even eliminate them.

Regards,

PS. Just for the history we actually film print a LAD to the 5201 and then we skip frames unexposed so the printer lights are set to that LAD which is almost identical with the brunette lady LAD. So there is no problem to adjust the printer lights? and measure the black at the skipped frames area.


Hey, no problem. I'm just glad I could find someone that understood your problem. I thought your problem was completely different than the way it actually turned out to be, now that I read Mr. Case's rewording of it.
Although still and cine photography have the same formulae and general principals, I figured I'd hand the ball off here. Printing onto paper (which is the only kind I've done) is different than printing film onto film, although any sort of copying involves an increase in contrast and a loss of dynamic range.

I agree that it is likely you've hit the maximal amount of information that can be transferred from one system to another in your setup. While it's a "digital" file, remember the CRT is an analogue device, subject to the same sort of generational loss that film, and analogue tape is. The only improvement I could think to this system (besides using interneg film or burning straight onto print stock), would be where you had a CRT that is somehow in contact with the emulsion of the film. I'm not sure if that is possible from an engineering standpoint. I bought a film recorder for a few dollars once, but I never got it to work. My understanding is that they're all just very high resolution monitors whose light is focused by a lens onto the camera or laboratory stock. At any rate Dominic is definitely eminently more knowledgeable here. Listen to him, not me! I'm lucky if I have processed 10,000 ft. of film in my entire life, whereas he probably has several hundred million under his belt, if not more. Today I found out that Mr. Case works at the same lab that did all of the processing for the film "The Thin Red Line", so needless to say, I am even more impressed. I had no idea you're working for such a big outfit Dominic!

In any case, hope we've both been of some help and that you can visualize the whole process in your head.

As far as labs go, I have plenty of experience with that: when working with analog media like film, it is CRITICAL to have a lab whose owner you know personally, whether that means taking him out to dinner or talking to him for a few hours on the phone about his kids. You are going to get different results from every lab, no matter how highly they're ranked by Kodak. Maintaining perfect chemical control is impossible. Then of course, the matter of color timing is an incredibly subjective, intuitive thing.

Personally, I'm still pretty terrible at it after two years. I'll go through twenty sheets of 8x10 paper before I get a good print sometimes. When you're dealing with shots that are intentionally shot with color casts through filters or other means, this just adds to the opportunity for a misunderstanding. Again, a good relationship and a COMPLETE understanding between your organization and the lab are essential if you want to get back the results you've envisioned. It's possible to take a poorly-printed neg and print it elsewhere, but you don't want to add complexity to the process by adding nonstandard processing variables to it.

Perhaps, since I'm sure you're working with millions of dollars of equipment already anyway, I would recommend you get a transmission densitometer (which allows you to measure the D-max and D-min off of your film) so you can doublecheck to make sure the lab is getting everything right. Again, color timing, and chemistry control are as much arts as sciences, but if you're getting results that are widely off, you'll be able to let them know how far off they are, in definite, scientific terms.

You DO expose test charts or test CRT patterns on the film you run through the recorder for reference, don't you? At the very least you want to have gray cards or something exposed on the film as a reference guide.

You're kind of under the impression that all film of a certain type is the same. Ideally it would be, but there are variations that creep in from emulsion batch to emulsion batch. If you make the lab's job easier with charts and concrete instructions (don't badger them though; you don't want your lab angry at you), you're eliminating what is probably the biggest part of the problem at this point: the problem of inadequate communication between your crew and the crew at the lab.

(It'd help if both parties speak Greek, as anti-idiomatic as that is in English ;-) )

Regards,

~Karl Borowski
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