LAD Strips

Nitin Sagar · August 14, 2004

i want to have the following stuff...

1.Kodak TAF for 5218,5242

2. Unexposed LAD strip for 5218,5242 aND OTHER STOCKS IN VISION2

hoping to find it here...

John Pytlak RIP · August 14, 2004

I developed the LAD control method. I also developed the original TAF based on the work of Kodak researcher R.W.G. Hunt. Kodak supplies tools like LAD and TAF to laboratory customers and film-to-video transfer houses. Not normally needed by cinematographers.

http://www.kodak.com/US/en/motion/products/tools/

http://www.kodak.com/US/en/motion/support/....1.4.11.8&lc=en

LAD is supplied as processed control film. There is no need for multiple film types for LAD, as stock-to-stock differences are timed/graded relative to a single camera negative LAD. The master positive, duplicate negative, and print are intended only as representative references.

Likewise, one TAF usually is used to aid in telecine setup.

Check with your Kodak technical rep in India, or perhaps your lab could spare some samples.

neal · August 14, 2004

On a related question...how would I go about obtaining a Grey Card Plus? through my local Kodak rep as well?

Thanks in advance John, you're the best.

Nitin Sagar · August 14, 2004

In India it is said that the LAD standard provided by Kodak is not "appropriate".....

If I take unprocessed LAD Strip and process it in Indian LAB...i should read the LAD provided by KODAK..????

As a Cinematographer( :o also Producer) what matters to me is......WHEN a POST HOUSE burns/records me a 5242 master negative...i should be able to process it anywhere in the WORLD as long as that LAB follows the processing to obtain the LAD supplied by KODAK...

am i right or am i wrong????????

Edited August 15, 2004 by Nitin Sagar

Phil Rhodes · August 14, 2004

Hi,

> In India it is said that the LAD standard provided by Kodak is

> not "appropriate".....

What?

Why? How? In what way?

> should be able to process it anywhere in the WORLD

Well yes, that's the idea. This may be one of those circumstances where it probably doesn't matter in minutiae what standard people use so long as they all use the same one.

Phil

Nitin Sagar · August 14, 2004

Hi,

> In India it is said that the LAD standard provided by Kodak is

> not "appropriate".....

What?

Why? How? In what way?

> should be able to process it anywhere in the WORLD

Well yes, that's the idea. This may be one of those circumstances where it probably doesn't matter in minutiae what standard people use so long as they all use the same one.

Phil

"not appropriate" might have been a wrong word....in the nut shell...the LAD of the test strip(Processed in indian LAB) do not match to the given value of the manufacturer ...so in turn DP's tune themselves to what the LAB is capable of(...rather than LAB getting to specified LAD value)

... in my case i've just got 3 years of experience...i shot my debut film S16..processed at Frank Cramel's FTS Singapore( Kodak Image Care ).PERFECT PROCESSING.

35mm print is being made thro DI...the post house is recording a 5242...they claim they can process it only at A PATICULATR LAB.......the reason they give is calibration of there recorder to the LAB.

the LAB's calibration for processing is(should B) LAD. which means that if this LAB is getting a different LAD than the given value for LAD patch... either the LAD patch values are wrong or the LAB is not doing the processing correctly?

at the risk of being the black sheep .....i think(and some what belive) that the LAB is at fault and not the LAD values suppled by KODAK

i m not even sure if this paticular lab where the inter is being processed follows kit chemistry....

Dominic Case · August 17, 2004

Labs (particularly Image Care accredited labs) follow many more process parameters than just the LAD aim (which is simply a mid-grey). If it's an Image Care accredited lab, then it will be controlling the process on standardised sensitometric strips, and producing results that are consistently within tolerance of the Kodak aim. That tolerance is equivalent to about one third of a stop - day to day, hour by hour, month by month.

Originally, Kodak established a LAD system for setting up duplication and printing control. It was based on a starting point of 0.80R, 1.20G and 1.60B, which then approximated to an 18% grey exposure on the current colour neg stock. (John Pytlak will remember which it was as it is his system). But at the time there was (can you believe it) only one neg stock available.

In the many years that have intervened, manufacturing aims for colour negative have changed slightly as technology has advanced, so that shooting an 18% patch no longet gives anything very close to the original LAD aims. This doesn't mean that the lab is processing wrongly.

"Kit chemistry" simply means that the lab is using prepacked chemicals supplied by Kodak, rather than mixing its own and monitoring the results by regular chemical analysis.

John Pytlak RIP · August 17, 2004

For complete background on the use of LAD, my paper "Simplified Motion-Picture Laboratory Control Method for Improved Color Duplication" was published in the October 1976 SMPTE Journal, Volume 85, p781.

As Dominic notes, use of the Laboratory Aim Density control system assumes the laboratory already has a good system of printer and process control, and that the characteristics of the raw stock duplicating and print films are also well controlled (including proper shipping and storage conditions). The Kodak ImageCare system helps participating laboratories with control tools (e.g., process control surveys) and specifications:

http://www.kodak.com/US/en/motion/support/imagecare/

Here is information about the LAD Control System, with the aims for each film:

http://www.kodak.com/US/en/motion/support/....4.11.8.6&lc=en

The gray in the LAD Control Film has a Status M density of red=0.80, green=1.20, and blue=1.60. It is printed to a 1.00 density neutral gray (END) on the print. Aims for each duplicating film assure optimum curve placement for master positives and duplicate negatives. All films in the cut negative, regardless of film type, are color timed (graded) relative to the LAD control film using an electronic color analyzer. As Dominic notes, although the variety of films in use today can be accomodated by color timing relative to LAD, there should be no expectation that they will all print exactly like LAD (e.g., print at TAPE 25-25-25). Likewise, the Status M densities an 18% gray card exposure produces on the negative will vary with film type, and are NOT intended to match the LAD patch. (Incidently, the gray patch in the "LAD Girl" control film is NOT an 18% gray).

Some laboratories may have their own control methods, but these methods often share similarities to the LAD control method, usually based on a mid-scale gray patch printed to specified aims.

Digital Intermediates require additional control methods, since the tone scale and color reproduction of the image can be modified digitally, and there are additional factors in scanning and recording (e.g., flare) that can affect tone scale. Kodak has developed a "Digital LAD" and other tools to aid in control:

http://www.kodak.com/US/en/motion/support/....4.11.8.8&lc=en

Nitin Sagar · August 18, 2004

For complete background on the use of LAD, my paper "Simplified Motion-Picture Laboratory Control Method for Improved Color Duplication" was published in the October 1976 SMPTE Journal, Volume 85, p781.

where do i lay my hands on this paper?