CI of Blank Film

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Ornello

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Jorge said:
AH, but there is the rub Ole, this thing that you are assuming. The reality of it is very simple, I will send you a blank negative and you will tell me to what CI I developed it, you can send me a negative you have made and I will tell you what CI you developed it. Lets see who gets closer......

I also disagree that the "correct" CI has to be determined by a standard test negative. While I am sure Il douche bag will disagree, we do our "own" CI every time we expose a piece of film to a step wedge with known density gradient.

There comes a time when talking about theoretical ideas has to yield to the reality....Arguing that a piece of blank film has a CI just because it was "assumed" it was developed as the test strip done before IMO is ludicrous.

In the end some might enjoy this kind of pseudo intellectual discussion...I dont, I think I have explained as well as I can what I mean, I leave you all to hash this out.

Here is hoping we get the "Ignore this thread" button soon....


CI means what Kodak says it means: it's their term. There is no 'correct' CI, any more than there is a 'correct' speed of a tennis ball crossing the net. Where did you get that notion?

CI (gamma, G-bar) represents a degree of development. Kodak says so, in so many words.

You can't 'disagree that the "correct" CI has to be determined by a standard test negative.' There is no 'correct' CI, and the only way to measure CI is with a process control strip. You can't disagree with Kodak's definition, any more than you can disagree with the length of a mile. A mile is a defined term, and you have no say in the matter. CI is a defined term. Contrast can be measured any way you want, but Contrast Index is a term defined by Kodak.

You are a very confused person, Jorge.
 

Ornello

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psvensson said:
You have all gone absolutely insane.

Nope. 'Insane' is a legal term. You mean 'mad'. You want to express it this way: "You have all gone absolutely mad."
 

fschifano

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Stephen Benskin said:
So, according to Sandy it would be impossible for me to run a blank sheet of film to test for the amount of chemical fogging that would occur at a given CI...

Yeah, I think that's right. How can you tell with any certainty that there is fog unless you have a baseline measurement with wich to compare it? The only way to do it is to take a piece of film fix it out and measure the density of the support and gelatin. Then take a piece of unexposed film and run it through whatever developer you want and measure that density. What you'll have are TWO points on a chart. You can turn them into a slope if you like, but it makes no sense. What it will tell you is how much base fog you are getting with a particular developer and processing technique and that's all. But what the heck do I know. I'm just an old school, street smart, wise ass New Yorker and you probably don't want to hear what I REALLY think about all this.
 

Jorge

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Kirk Keyes said:
Hi Jorge!

I didn't mean to imply that a lot of usefull information could be derived from a blank piece of film developed to a particular CI. And you are right, you cannot determine the CI of a processing run merely from a blank sheet of film. I beleive I said that in my orginal post. I would be a fool to argue otherwise.

Steve did point out that one can determine the base+fog level from that blank sheet of film. That's about all.

But the sheet is still associated to a particular CI.

Kirk, IMO this is a circular argument, you cannot determine a slope unless you have two points, but then every point along that line will have a "slope" associated with that line. So what comes first, the chicken or the egg?

YOu and Ole are arguing that every single point along the line has an associated slope and as such a piece of blank film has an "associated" CI if it is developed in the same way a previously calculated CI. WHile this might be theoretically true, it can only be proven if you have previously calculated a CI , along the same lines that you can only "associate" a slope to a point only after you have drawn the line....SO far neither you or Ole have told me what is the slope of a point with cartesian coordinates 2, 5....

I took the time to explain my position to you given our past exchanges, but I am really done with this....I really think it is a waste of time, like you I rather masturbate to porno.....
 

Ornello

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fschifano said:
Yeah, I think that's right. How can you tell with any certainty that there is fog unless you have a baseline measurement with wich to compare it? The only way to do it is to take a piece of film fix it out and measure the density of the support and gelatin. Then take a piece of unexposed film and run it through whatever developer you want and measure that density. What you'll have are TWO points on a chart. You can turn them into a slope if you like, but it makes no sense. What it will tell you is how much base fog you are getting with a particular developer and processing technique and that's all. But what the heck do I know. I'm just an old school, street smart, wise ass New Yorker and you probably don't want to hear what I REALLY think about all this.


I'm outa here...gotta develop some film..don't know what CI, and don't care...but I do know exactly how long I'm gonna develop it...
 
OP
OP

Kirk Keyes

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Jorge said:
Kirk, IMO this is a circular argument, you cannot determine a slope unless you have two points, but then every point along that line will have a "slope" associated with that line. So what comes first, the chicken or the egg?

Jorge - think about how process control fits into this. I'm pretty sure that you have a good understanding of this subject. If you have set up a processing system, and you can reliably process your test films to target CIs, you can be pretty darn certain that any other sheet of film, blank or otherwise, will be processed to the specified CI, without any actual measurement of the CI.

So I guess the answer is process testing comes first, and then process control (hopefully) comes second. One most certainly does need to do testing before hand with a processing system that is in control, or at least run a second sheet with that processing batch.

You wrote, "WHile this might be theoretically true, it can only be proven if you have previously calculated a CI , along the same lines that you can only "associate" a slope to a point only after you have drawn the line...."

Yes, I agree that you must already know the development conditions needed to achieve a particular CI. I don't think I ever argued otherwise. As for the line part of that statement, you don't even need to draw the line, you just need to know the coordinates of the two points.

"SO far neither you or Ole have told me what is the slope of a point with cartesian coordinates 2, 5...."

You only have one point (2,5). There is no line. Therefore there is no slope.

Kirk
 

Jorge

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You only have one point (2,5). There is no line. Therefore there is no slope.

THANK YOU! In the same manner I only have a blank piece of processed film...I have no CI......yeah, yeah, but you do if you processed the same way you processed the test strip and calculated the CI...we all got it, makes no sense to me to continue arguing this.....
 

Jorge

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BTW Stephen, if there are two people on this forum who definitly have absolutely no admiration for each other are King and I.....so you are way off base to think this is a "mutual admiration" ass kissing, we just happened to agree on this one instance on the non sensical nature of your blank film example....
 

Donald Miller

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Just to give you all an idea of the calibre of individual that we are dealing with here, I have taken the liberty of copying and posting an email that was sent to me a little while ago.

Donald,

Why don't you say something useful for a change instead of some snide remark? You guys are a bunch of ****ing sheep jumping on the trash the new guy bandwagon.

Stephen Benskin



***I will go on to say that all of the words were spelled out completely in the email that I received.
Donald Miller
 

sanking

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Jorge said:
BTW Stephen, if there are two people on this forum who definitly have absolutely no admiration for each other are King and I.....so you are way off base to think this is a "mutual admiration" ass kissing, we just happened to agree on this one instance on the non sensical nature of your blank film example....

Jorge,

Thanks for that comment.

Sure glad that you cut in the bud the suggestion that we are engaged in any kind of "ass kissing" mutual admiration society.

Sandy
 

Jorge

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sanking said:
Jorge,

Thanks for that comment.

Sure glad that you cut in the bud the suggestion that we are engaged in any kind of "ass kissing" mutual admiration society.

Sandy

Yeah well, the ass kissing suggestion worried me.......lol...
 

smieglitz

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Ornello Pederzoli II said:
I'm outa here...gotta develop some film..don't know what CI, and don't care...but I do know exactly how long I'm gonna develop it...

Make sure to measure the developer formula, dilution and temperature before you do.

You already have the agitation technique down.
 

sanking

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Stephen Benskin said:
I tried to make nice (notice the apology for calling your statement nonsense?), but you continue to berate people. I am just standing up against your arrogance. You began by blowing me off. I just dug in after that.

Remember, there is someone who always knows more. I happen to know something about exposure theory and tone reproduction theory. I’m less knowledgeable in many areas. I might be coming down on you regarding some of your misstatements (and they may be slight) just to prove a point. If you wish to start over and give people the respect they desire, I'm willing to play nice.

If you've noticed the SBR and Luminance thread, I quote Davis' who disputes what you have said, and while your EFS statement isn't exactly gibberish, it is either wrong or the statement was confusing enough to make it appear wrong. I wrote about that.

Hi Stephen,

In response to your message. Your comments in quotes of course.

“A very unwise and arrogant move, especially when you don't know who you are blowing off.”

Gee, this sounds like a threat! So who are you? Member of the Mafia? Have prints in the Met? You going to cut off my source of income? Recommend that Photo Techniques not publish any of my work?

“I'm less knowledgeable in many areas.”

Really? I found that hard to believe. Sorry, I was being disingenuous. In fact I find that very easy to believe.

“If you wish to start over and give people the respect they desire, I'm willing to play nice. I'm big enough to admit we may have gotten off to a bad start.”

Wow. You are a really swell guy! So I kiss your ass and all is forgiven? Ummm, on the other hand maybe we should just play hard ball for a while?

But Stephen, it could have been so different, if only you had made it clear from the beginning that your major purpose was to defend OP, as you did later when you commented, “Sandy, my point about SBR is that anyone can nit-pick someone else. Maybe I should have just said stop attacking OP, but I wanted to make a point. Sorry you missed it.”

Stephen, I am sure that some of us would have embraced you from the start if you had just had the cojones (balls) to state your true intentions at the beginning. But, alas, you did not, so there we are.

Best Wishes,

Sandy
 
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Claire Senft

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I got it.

I have digested all the foregoing. Spirited debate. Thank God for the endless supply of electrons.

I am left with but one bit of confusion?

Jorge, who is Il douche bag II? How does he get all that p***sy?
 

sanking

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Stephen Benskin said:
Sandy,

You really are a small, petty, bastard. There is no reasoning with someone like you. What an *******.

Hi Stephen,

Thanks. And no offense taken. Coming from you I consider the comments high praise. (edit, edit, edit in the interests of decorum)

Best,

Sandy
 
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gainer

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Stephen Benskin said:
Sandy,

You really are a small, petty, bastard. There is no reasoning with someone like you. What an *******.
I thought I was leaving this kind of talk behind when I came to this forum.

I guess the first guy who developed a blank piece of film in XTOL in order to find its fogging properties is lucky he got a good batch. Or did he?

It is NOT always possible to predict the exact CI of a process control strip. If it were, there would be no need for those strips. If you are going to correlate fogging vs developing time-temperture as an indicator of CI, it is utter nonsense to do it with a blank piece of film. No matter how closely you control the time and temperature and agitation and even if you always do it in the same phase of the moon, you will never know if you got a bad batch of developer or not. You do not know the CI. The way to measure CI used to be to find the density range over a log exposure range of 1.5 that begins where the local slope of the H&D curve is 0.3 of the average. How do you do anything like that with a blank piece of film?

Luminance is a quality of luminous bodies. Brightness is what reflecting bodies show us of bodies that have been illuminated by luminous bodies.
 

Jorge

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Claire Senft said:
I have digested all the foregoing. Spirited debate. Thank God for the endless supply of electrons.

I am left with but one bit of confusion?

Jorge, who is Il douche bag II? How does he get all that p***sy?

Claire, I dont know who is Il douche bag II, but I do know who is *I*......I bet you know too.. :D
 

phfitz

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Hi there,

Kirk : Just to light it off.

A leason in reality that your parents should have taught you at the wrong end of a 1 1/2" black leather cute removing tool:

'To intentionally waste someone's time is the most vial and disgusting insult desived by the human race. It is exactly to waste someone's one time on earth that we lock people in prison for crimes committed.'

"Cute" never applies to a male.'

Enjoy the rest of your life.
 

Claire Senft

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Questions for Ornello

Ornello tiwce you have posted a copy of a Kodak document. I thank you for you help. My monitor squeezes the document down somewhat and it becomes somewhat difficult to read. The document is about characteristic curves. It makes several mentions of gamma. No where in this document can I find CI mentioned.

Questions:
Is CI mentioned in the document as posted?

If not, how does it help the discussion?
 

Claire Senft

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questions for Kirk, Ole and Stephen

Given: A piece of developed film exposed to a single tone has CI.

I have less interest in theory and than I do in practice.

Having this piece of developed film in front of me, how do I determine what the CI actually is?

Is this information of any practical use?
 

Ole

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Claire Senft said:
Given: A piece of developed film exposed to a single tone has CI.

I have less interest in theory and than I do in practice.

Having this piece of developed film in front of me, how do I determine what the CI actually is?

Simple: You can't. The film doesn't "have" CI, it's been developed to a CI. You can't measure one point and create a curve from it.

Claire Senft said:
Is this information of any practical use?

None whatsoever.
 
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