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PUSH without increasing Contrast


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#1 Hamid Khozouie

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Posted 09 June 2005 - 10:04 AM

In pushing , increasing contrast & grain is obvious.For reducing the contrast, these options are useful or not ? Do you have any suggestions ?
*Selecting a low contrast film.
*Using of filters like ultracon.
*Using of varicon , or flashing.
*Do we can change the PH of chemicals and reducing the contrast.
Thank you.
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#2 David Mullen ASC

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Posted 09 June 2005 - 10:11 AM

I think the best option is starting out with a wider-latitude, lower-contrast film because it is more effective than flashing or LowCons at increasing shadow detail.

Only problem is that all these methods of lowering contrast also make grain more visible, and pushing makes the image more grainy, so if you try and lower the contrast of a pushed image, you will see the grain easier.

However, you should try a low-con stock, maybe pushing Expression 500T or the new Fuji F-400T.
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#3 John Pytlak RIP

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Posted 09 June 2005 - 03:33 PM

I think the best option is starting out with a wider-latitude, lower-contrast film because it is more effective than flashing or LowCons at increasing shadow detail.

Only problem is that all these methods of lowering contrast also make grain more visible, and pushing makes the image more grainy, so if you try and lower the contrast of a pushed image, you will see the grain easier.

However, you should try a low-con stock, maybe pushing Expression 500T or the new Fuji F-400T.

<{POST_SNAPBACK}>


Here are the Kodak "low contrast look" stocks:

http://www.kodak.com....4.4.4.12&lc=en

http://www.kodak.com....4.4.4.20&lc=en

"Pull Process" can certainly reduce contrast, but be careful that speeding up the processing machine to reduce developer time doesn't shortchange the "tail end" solutions and washes.

Filtration, flashing, and soft lighting are the traditional tools that can be used to reduce contrast.
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#4 Tim J Durham

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Posted 09 June 2005 - 03:51 PM

Here are the Kodak "low contrast look" stocks:

http://www.kodak.com....4.4.4.12&lc=en

http://www.kodak.com....4.4.4.20&lc=en

"Pull Process" can certainly reduce contrast, but be careful that speeding up the processing machine to reduce developer time doesn't shortchange the "tail end" solutions and washes.

Filtration, flashing, and soft lighting are the traditional tools that can be used to reduce contrast.

<{POST_SNAPBACK}>


Do they teach the Ansel Adams zone system in film school? It seems like that would be directly relevent to cinematography. I had to learn it in college, but I was a fine art major (photography) at the time and it was one of the few things I remember actually having to WRITE about in art school, 'cept for my art history classes.
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#5 David Mullen ASC

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Posted 09 June 2005 - 06:50 PM

The Zone System has its followers in cinematography, but to some degree, it can only be applied in a generalized, conceptual way. The system is really designed for b&w still photography where you can control gamma through processing -- and contrast through printing -- in order to "place" tonal elements in the original scene into the Zones you want them to fall.

In other words, you have a low-contrast scene where most of the information lies in the middle zones, you can increase the gamma in processing and print on more contrasty paper, maybe with filters, to place the darkest elements and lightest elements at the far ends of the Zones and create an image with a full range of tones from white to black.

Motion picture color cinematography is too automated in processing, and too resistant to changes in gamma, to make the Zone System as effective, plus you have limits on types of print stocks.
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#6 Hamid Khozouie

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Posted 10 June 2005 - 08:47 AM

"Pull Process" can certainly reduce contrast, but be careful that speeding up the processing machine to reduce developer time doesn't shortchange the "tail end" solutions and washes.


Dear John
When we push we want to increase ASA ,not decrease it (pull)

However, you should try a low-con stock, maybe pushing Expression 500T or the new Fuji F-400T.


The best way as dear David says is better to select low contrast stocks.
But is there any idea about PH IN CHEMICALS ???.......
Thank you for considerations.
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#7 Jarin Blaschke

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Posted 10 June 2005 - 12:25 PM

Reducing the PH of a developer will basically do the same thing as leaving it in the solution for less time.
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#8 John Pytlak RIP

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Posted 10 June 2005 - 01:05 PM

Dear John
When we push we want to increase ASA ,not decrease it (pull)

The best way as dear David says is better to select low contrast stocks.
But is there any  idea about PH IN CHEMICALS ???.......
Thank you for considerations.

<{POST_SNAPBACK}>


The on-line H-24 Kodak processing manual shows the effect of changing processing parameters, including the chemical concentrations and pH:

http://www.kodak.com.../h248/h2408.pdf

Most labs vary the developer TIME to push or pull a process, a few might use TEMPERATURE, none that I know of change the pH or process chemistry.
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#9 Hamid Khozouie

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Posted 12 June 2005 - 05:36 AM

Most labs vary the developer TIME to push or pull a process, a few might use TEMPERATURE, none that I know of change the pH or process chemistry.

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I means , we change time developer for PUSH & at that time changing PH may be reducing contrast .
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#10 L K Keerthi Basu

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Posted 12 June 2005 - 09:49 AM

I means , we change time developer for PUSH & at that time changing PH may be reducing contrast .

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As John said,I have heard only about increasing the Time and Temp for achiving the PUSH process. When we alter the PH, developing will not be under our control.Some times when changing the Chemistry they may lead to decompose the equaliberium of the formula, they cause some color shift and even make the chemical fog,because I tried this before.
In earlier Black and White film processing some were increasing the Ph of the formula with the excess alkalis to finish the work very fast but this is not the right way. They buildup high contrast negatives.

L.K.Keerthibasu
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#11 David Mullen ASC

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Posted 12 June 2005 - 10:25 AM

I means , we change time developer for PUSH & at that time changing PH may be reducing contrast .

<{POST_SNAPBACK}>


ECN2 processing at labs is highly standardized so you wouldn't be able to alter the chemistry anyway unless you owned your own lab; there are other customers using the same bath as you remember.

In the 1970's there was a lab in New York called TVC which had a process called ChemTone, a form of chemical flashing combined with pushing, used for movies like "Taxi Driver". It didn't cause an increase in contrast because it caused an increase in the base fog level (i.e. blacks were less black.) TVC & ChemTone no longer exists.
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#12 Luke Prendergast

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Posted 12 June 2005 - 04:42 PM

With E6-type reversal processes +pH will shift to magenta, -pH to green-yellow. Don't know about the effect on negative processes.
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#13 Hamid Khozouie

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Posted 13 June 2005 - 02:01 AM

In the 1970's there was a lab in New York called TVC which had a process called ChemTone, a form of chemical flashing combined with pushing, used for movies like "Taxi Driver".  It didn't cause an increase in contrast because it caused an increase in the base fog level (i.e. blacks were less black.)  TVC & ChemTone no longer exists.

<{POST_SNAPBACK}>

Dear David
How can I further information about this method ??
Thank you.
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#14 David Mullen ASC

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Posted 13 June 2005 - 03:08 AM

Trouble is that TVC Labs kept the details of ChemTone a secret and then they went out of business, probably more than a decade ago.

Other problem is that in order to deviate from standard ECN2 processing & chemicals, you'd either have to own your own lab or be able to take over someone else's. So unless your best friend owns a lab and will let you alter the processing for your projects only, you can't really change the ECN2 processing set-up because other people send their film through the same bath (push or pull processing is an easier adjustment since it means just changing the amount of time the film spends travelling through the machine.) So while I'm sure some simple experimenting could probably recreate ChemTone, no lab would let you do that.

Instead of chemical fogging, you could try combining flashing with push-processing, plus use a low-con stock.
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#15 John Pytlak RIP

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Posted 13 June 2005 - 02:55 PM

Searched the Internet for Chemtone information:

http://celebrities.t...ches_John.shtml

In 1975 the TVC labs introduced a chemical process called Chemtone (developed by Dan Sandberg, Bernie Newson, and John Concilla) that was a much more sophisticated version of flashing. Chemtone 'was first used on such films as Harry and ..."


http://www.groupsrv....opic.php?t=2896

Quote:
peterh5322@aol.comminch (Peter H.) writes:

A name like Chem-Tone may be registered as a trademark, but not copyrighted.


Very true and I doubt that Danny ever thought to "protect" the term
back then. But what was "chem-tone" (sounds alot like a paint,
but that was kemtone)?

I remember talking to Danny and he made a point that when he
developed Eastman color negative that he didn't "add any salt or
pepper" as he refered to other labs processes.

Was this a variation on positive processing like skip-bleach?


Chem-Tone was TVC's name for forced processing combined with chemical flashing
(as opposed to optical flashing).

This process allowed the use of available lighting in many shots in NASHVILLE,
1975.

However, the intercutting of the conventionally processed ECN in the rest of
the show with the Chem-Tone footage was quite jarring to me during theatrical
projection. (This might not be so noticeable in video.)


Certainly there are chemicals that can be added to a process to produce chemical fogging. But producing a little fogging uniformly in a controlled manner is the trick!
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