Portra 160 VC or color negative exposure experts?

2F/2F said:

However, it has three curves (or more in a four color layer film), and they don't exactly line up with each other.

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The curves line up well if the film has been properly processed. This is evident in the fact that film is capable of reproducing a gray scale, indicating tracking of the red, green and blue curves along the linear portion of the characteristic curves.

* * * * *

A gray scale represents changes in exposure. Therefore it seems to me that there should be no significant shift in color a stop or two away from normal exposure in scenes where most everything falls on the linear portion of the curves, but a significant change could take place in the overall look of a scene with a lot of highlights or shadows (off the linear portion of the curves), where exposure changes would be aggravated, or scenes with improper color temperature for the film, as has been mentioned. Just how much color information there is in the highlights and shadows would also be a factor, I'm thinking. Therefore how much change there is, is dependent on the nature of the image itself. Not all scenes will respond exactly the same to changes in exposure.

Significant changes taking place could be also due to improper processing which would cause crossover and non-tracking curves. Therefore the process quality should be evaluated if it has not already been checked.

Tim Gray said:

When I look at the Portra characteristic curves, I do see the green curve having a noticeably different slope than the others.

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Keep in mind that these curves can change with processing. These are Kodak's results; different labs and home processing can give quite different results. I process at home and my curves do not look quite like Kodak's but are reasonably parallel and give a good gray scale when printed.

I have noticed that while I have mixed results with Portra films, but 160NC has been rock steady for me. That said I had no problems with 220 format 400VC until the last roll I shot I had a few frames in the middle of the roll and with the same lighting as most of the roll I could see a slight blue cast. Maybe a cloud was overhead right then, or there was a blue car behind me, or I was shooting from the shade into the sunlight. I probably would have never noticed that the "problem" if it wasn't for the fact that my roll of film was a mixed bag of shots with flash photos and daylight shots at all kinds of angles to the sun. I was just enjoying shooting so I wasn't paying a lot of attention or taking notes but of the three photos with the blue cast I recall one was taken from shade of people in sun and in front of a open garage (box of shade) so I assume that this was more a problem of my failing to meter the shot correctly than the film.

All that said, I have to say that for me at least any problems that I have with Portra and color shift have to do with the device right behind the camera that is looking through the viewfinder.

RPC said:

The curves line up well if the film has been properly processed.

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Take a look at the manufacturer's data for any color neg film, and you will see that the curves do not exactly overlap each other even with perfect factory processing. Thus, in cases of underexposure, not all colors are underexposed equally. When underexposure occurs, some layers are always underexposed more than some others. Because of this, color balance becomes "wonky" in the least-exposed areas.

In the same vein, if you shoot in extremes of color temperature away from that for which the film was designed, a severe exposure mismatch between color layers occurs, because even if certain layers have received enough exposure for everything in the picture to land on the curve, others may not have. For instance, when shooting daylight film under tungsten illumination, the blue-sensitive layer ends up receiving a good deal less exposure than the other two, and you see this most in the darkest areas of the print.

So, to achieve the best color balancing ability, one must give enough exposure to the layer that will be the least sensitive in the given color temperature. I don't know how to do this exactly, but since color neg film allows so much slop, I usually add a stop and don't worry about it.

FWIW, the same thing happens with black and white film, except that in this case, there is one layer of emulsion that responds to the entire range to which it is sensitized. Whenever possible, I give a b/w film extra exposure when shooting in color temperatures far away from the area of 5,000 K.

Juan Valdenebro said:

Hi Mark,

1. No. It's not about brightness. It's about color: it's about the limits a light sensitive color media has when representing a real color and its real transitions to that same color when it reaches its own shadows and highlights... That color representation on film requires a precise amount of light: a bit less light or a bit more light produce, ON NEGATIVE, different color shifts.

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Real you say. Real is subjective in color photography. I know people who call Velvia's colors real, others that call Astia's real, others that call Reala the bomb, and people shooters that say Portra is the absolute best.

All these films provide different palettes of color, none of them are "real".

I do agree that when you are shooting for a very specific result, from a specific film, that will be processed a specific way, and printed on a specific paper; accurate exposure is very helpful.

The result may be what you call real, it is what I call placement and interpretation.

Juan Valdenebro said:

Forget the next steps: wet printing or scanning. Those are not discussed here... Use them as you prefer... This thread's about what happens to film. And if you don't have information on this subject, or believe the amount of light has no incidence in color or color temperature visible on neutral tones, you have the right to that opinion, but you're adding nothing to this thread.

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Jaun,

Unless you are going to display the negative as the the final product, "forgetting the next steps" is silly, in fact it borders on ridiculous.

In fact you allude to that problem in this last paragraph when you talk about the "color temperature visible on neutral tones".

To make a positive image from a Portra negative we have to shine light through it, correct it's balance, not just for the scene (which is arbitrary) but for the orange base (which is affected by processing, age, heat, film batch), and invert it to some media where the paper adds a color bias too.

Papers have their own curves with shoulders and toes that affect how much of a the film's curve will be visible and the color balance. In a straight print (especially from a thick negative) much of the info on a negative falls outside the paper's range. Burning and dodging can bring much of that info into the papers range, but that process is arbitrary.

These requirements are variables, their application is arbitrary, not fixed by law or the limits in physics and the "color balance" isn't "visible" without applying the variables.

Making a positive is a required part of the process; if you want to see color balance in real life, you can't ignore the process of making the positive.

Juan Valdenebro said:

2. No. Not even filtering differently we get identical results.

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I'm not saying that the photos will be exactly the same, I'm saying that the color balance doesn't move much and essentially equal colors are available in the print. The result is fully and absolutely dependent upon the printing process.

How we use the enlarger to place exposure on the paper to create our photo and how much we burn and dodge, is purely arbitrary, just as our color preferences are.

Reality is not what we get on paper, we get an interpretation.

Juan Valdenebro said:

3. Wrong. Magic in your imagination only: to me this is predictable and stable 100%, a science... This is just optics and chemistry... As C-41 is a standard, indeed it's careful exposure and filtering on camera PRECISELY what produces the best color once and again.

Cheers,

Juan

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Sure C-41 (and RA-4) has a commercial standard; some labs are very good at that, some aren't. A perfect standard in practice it is not. Lab complaints here on APUG are ample proof of this.

Not only that, just as for B&W film, the process can be adjusted, with time and or temp, to suit the choices of the photographer's vision. With practice Push/Pull, Expand/Contract are very workable and used regularly with C-41.

2F/2F said:

Take a look at the manufacturer's data for any color neg film, and you will see that the curves do not exactly overlap each other even with perfect factory processing. Thus, in cases of underexposure, not all colors are underexposed equally. When underexposure occurs, some layers are always underexposed more than some others. Because of this, color balance becomes "wonky" in the least-exposed areas.

In the same vein, if you shoot in extremes of color temperature away from that for which the film was designed, a severe exposure mismatch between color layers occurs, because even if certain layers have received enough exposure for everything in the picture to land on the curve, others may not have. For instance, when shooting daylight film under tungsten illumination, the blue-sensitive layer ends up receiving a good deal less exposure than the other two, and you see this most in the darkest areas of the print.

So, to achieve the best color balancing ability, one must give enough exposure to the layer that will be the least sensitive in the given color temperature. I don't know how to do this exactly, but since color neg film allows so much slop, I usually add a stop and don't worry about it.

FWIW, the same thing happens with black and white film, except that in this case, there is one layer of emulsion that responds to the entire range to which it is sensitized. Whenever possible, I give a b/w film extra exposure when shooting in color temperatures far away from the area of 5,000 K.

Click to expand...

Curves may not track perfectly but the point I was trying to get across was that if properly processed they line up well enough in the linear portion to produce a good gray scale. Therefore any exposure changes taking place solely on the linear portion shouldn't show any appreciable shift in color. I agree with you that changes involving parts of the image off the linear portion of the curves will cause some degree of color shift in those areas, and can change the overall look of the image. How much, of course will depend upon the nature of the image itself.

markbarendt said:

Real you say. Real is subjective in color photography. I know people who call Velvia's colors real, others that call Astia's real, others that call Reala the bomb, and people shooters that say Portra is the absolute best.

All these films provide different palettes of color, none of them are "real".

I do agree that when you are shooting for a very specific result, from a specific film, that will be processed a specific way, and printed on a specific paper; accurate exposure is very helpful.

The result may be what you call real, it is what I call placement and interpretation.



Jaun,

Unless you are going to display the negative as the the final product, "forgetting the next steps" is silly, in fact it borders on ridiculous.

In fact you allude to that problem in this last paragraph when you talk about the "color temperature visible on neutral tones".

To make a positive image from a Portra negative we have to shine light through it, correct it's balance, not just for the scene (which is arbitrary) but for the orange base (which is affected by processing, age, heat, film batch), and invert it to some media where the paper adds a color bias too.

Papers have their own curves with shoulders and toes that affect how much of a the film's curve will be visible and the color balance. In a straight print (especially from a thick negative) much of the info on a negative falls outside the paper's range. Burning and dodging can bring much of that info into the papers range, but that process is arbitrary.

These requirements are variables, their application is arbitrary, not fixed by law or the limits in physics and the "color balance" isn't "visible" without applying the variables.

Making a positive is a required part of the process; if you want to see color balance in real life, you can't ignore the process of making the positive.



I'm not saying that the photos will be exactly the same, I'm saying that the color balance doesn't move much and essentially equal colors are available in the print. The result is fully and absolutely dependent upon the printing process.

How we use the enlarger to place exposure on the paper to create our photo and how much we burn and dodge, is purely arbitrary, just as our color preferences are.

Reality is not what we get on paper, we get an interpretation.



Sure C-41 (and RA-4) has a commercial standard; some labs are very good at that, some aren't. A perfect standard in practice it is not. Lab complaints here on APUG are ample proof of this.

Not only that, just as for B&W film, the process can be adjusted, with time and or temp, to suit the choices of the photographer's vision. With practice Push/Pull, Expand/Contract are very workable and used regularly with C-41.

Click to expand...

Hi Mark,

It seems to me you prefer to discuss and avoid adding to the precise thread's subject, instead of adding to the precise thread's subject and avoid discussing... I'll explain it to you again:

OK, as you need it, also consider a) wet printing, or b) scanning, as a part of this... It's exactly the same: it is irrelevant the second step used... What we are talking about here, is how much more or less exposure, (MAIN SUBJECT) close to box speed ISO rating, produce warmer or colder results ON NEGATIVE, as those changes in color temperature are EVIDENT on negative's neutral tones and can be checked BOTH with wet printing and scanning: no matter if you use a) or b) to check results, you just get THE SAME RESULTS when comparing one frame and the next one on a bracketing because all this depends on what exposure produces ON NEGATIVE and doesn't depend AT ALL on analog or digital filtering. Of course we all can affect and change color during printing with analog or digital filtering, but we also have AN ORIGINAL, a precise and physical one, as color precise as slide film, and you can be good or bad at knowing that original. Looks like all your posts are hiding behind the "I'm not good at knowing my negative's real tone" mask...

Thanks for adding to the precise thread's subject (metering and exposure, coolness and warmth on negative) and avoid discussing.

Cheers,

Juan

Juan Valdenebro said:

My question is:

How does exposure affect Portra 160 VC's tone if we talk just about color temperature?

I'm testing it and found it goes both warm and cold with overexposure depending on the kind of light in the scene, and there's no optimal ISO rating: there are optimal ISO ratings depending on the kind of light... I find the best, cleanest, most accurate colors, are obtained after incident metering at 160, 80 and 40, depending on the nature and direction of light, and looks like the change in color temperature is more than visible with a 1 stop variation...

Has someone got similar results?

Cheers,

Juan

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Juan,

If you are using an enlarger as your checking system for two well exposed Portra negatives 1 or even 2 stops apart and adjusting the enlarger exposure to correct for the difference in negative density between the two to place a specific mid tone subject at a specific brightness level on the paper: A 1 or even 2 stop difference between two negatives should provide almost no change in color temperature in the mid tones.

BUT!

If you are not adjusting the enlarger's exposure for the differences in negative density the brightness of your print will change, the change in brightness across the photo may make it look warmer or cooler depending on the subject matter.

If you want a constant color temperature between any two negatives taken on the same film and in the same lighting, you need to change the enlarger exposure; it's that simple.


For clarity I want to make a point. Scanners do make a difference because they don't change exposure. The brightness difference in what they see and are therefore able to catch will show a significant difference between any two differently exposed frames.

There are real and significant differences between analog and digital systems when they are used to check what's in the negative.

The scanning process and it's results are off topic here on APUG.

So I have a question.

Are the results you are seeing checked on an enlarger that has been properly adjusted for the density differences between your negatives?

Hi Mark,

The options for any forum member including you and me, are:

1. Exposure below, at, or 1 or 2 stops above box speed, just doesn't change how warm or cool Portra 160 VC render a given scene. They're identical frames: no color shift. No difference ON FILM.

2. Underexposure or overexposure can make Portra 160 VC give slightly different color temperature to a given scene. Even if we can filter on enlarger to make frames look close on print, or for example make a cold scene look warm, certainly I believe there are differences ON FILM...

I think both wet printing and scanning can show option 2 reflects real behavior of that film. Looks like you think reality is option 1. Do we agree by now?

After years of wet color printing, you and I know how to get the best from a negative, and how to filter in any way we want to make a print look: cooler or warmer... I have made cold shots (done in the shadows without warming filter) look warm after enlarger filtering, and I have also made look neutral a few shots done under orange sunset light with saturated film... You and I know how to do it, both with enlarger and with photoshop... When I cursed my six-year career on photography I had to wet print from color negative for three years, after only B&W years...

I have a better idea: maybe you could tell me what would be, from your experience, the best way to compare two differently exposed frames to see if one of them is warmer than the other one... How would you do it? There must be a way you can imagine: a way you'd trust in... Just tell me how you would do it... Stop wondering about the second step (analog or digital)... Any way comes to mind?

The first answer here and kind welcome, were yours, and you've been very patient and after six posts I know you take this seriously as I do... Maybe I could send you my negatives (they're just a test: could even get lost, no problem...) and see how your preferred procedures interpret them... What do you say? That would be interesting... My email is juanvaldenebro@gmail.com, I'd really appreciate to see your opinion on the same images I've used... I'd send you also information on the incident meterings, filtering (same in all scenes) and f-stop and shutter speed for every shot... I'd send you six scenes, two in the shadows, two on frontal sun and two on lateral sun, and the same three shots for every scene: N, N+1 and N+2...

Cheers,

Juan

markbarendt said:

For clarity I want to make a point. Scanners do make a difference because they don't change exposure. The brightness difference in what they see and are therefore able to catch will show a significant difference between any two differently exposed frames.

Click to expand...

I know this is slightly off-topic, but just to nitpick, some scanners do allow you to change exposure or adjust hardware gain on the scanner.

Juan Valdenebro said:

I have a better idea: maybe you could tell me what would be, from your experience, the best way to compare two differently exposed frames to see if one of them is warmer than the other one... How would you do it?

Click to expand...

I know this wasn't directed at me, but here's a thought. It could very well be wrong; if it is, please correct me - I want to learn.

What I'm going to say will ignore the color balance/dye spectrums of the printing paper and/or scanner. Let's assume this part of the equation is ideal, though it certainly does make a difference. There are two possible references for 'neutral' in a color neg.

The first is the negative base. Balance out the negative base to be neutral, adjust exposure to suit the picture, and colors will fall where they fall. I would think this option would reveal the 'true' color balance of the image of the film, relative to the color temp that the film was designed to be shot in (5600 K in this case).

The other possible reference would be a gray card in the frame. I'll admit there are possible variations here - a black card, a white card, or any other pure neutral tone in the photo. Regardless, the concept is the same. Adjust exposure, color balance the print/scan for the pictured neutral tone to actually be neutral, and the rest of colors will end up where they end up. This method would compensate for color temperature differences in the light from the film's native balance (5600 K). Obviously, we all know that if you shoot in warm sunset light or through a warming filter, you don't necessarily want to balance your grays to be neutral - they actually *are* warm. However, using this method in consistent light and a step chart should let you see how shadows and highlights might differ in color balance.

In practice, I don't think I strictly adhere to either method. They both can provide a good starting point, but then I adjust the color to be pleasing. But if you really want to 'find out what's on the film,' then I don't think we can just adjust for pleasing colors. However, it's still a useful test for determining which film works better for you.

With overexposure or underexposure, at some point you are going to get into the toe/shoulder regions of one or more of the emulsion layers. When you do, color balance in that tone would have to change. This has already been stated by other - I think we all agree on principle that under/over exposure can change the color.

Juan Valdenebro said:

Thanks for the welcome, Mark...

Indeed I used a B+W 81B filter on my Nikkor 105 2.5 for all the shots in the test

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The 105 2.5, the holy grail of old school Nikon portrait glass, I will someday own one.

Tim Gray said:

I know this wasn't directed at me, but here's a thought. It could very well be wrong; if it is, please correct me - I want to learn.

What I'm going to say will ignore the color balance/dye spectrums of the printing paper and/or scanner. Let's assume this part of the equation is ideal, though it certainly does make a difference. There are two possible references for 'neutral' in a color neg.

The first is the negative base. Balance out the negative base to be neutral, adjust exposure to suit the picture, and colors will fall where they fall. I would think this option would reveal the 'true' color balance of the image of the film, relative to the color temp that the film was designed to be shot in (5600 K in this case).

The other possible reference would be a gray card in the frame. I'll admit there are possible variations here - a black card, a white card, or any other pure neutral tone in the photo. Regardless, the concept is the same. Adjust exposure, color balance the print/scan for the pictured neutral tone to actually be neutral, and the rest of colors will end up where they end up. This method would compensate for color temperature differences in the light from the film's native balance (5600 K). Obviously, we all know that if you shoot in warm sunset light or through a warming filter, you don't necessarily want to balance your grays to be neutral - they actually *are* warm. However, using this method in consistent light and a step chart should let you see how shadows and highlights might differ in color balance.

In practice, I don't think I strictly adhere to either method. They both can provide a good starting point, but then I adjust the color to be pleasing. But if you really want to 'find out what's on the film,' then I don't think we can just adjust for pleasing colors. However, it's still a useful test for determining which film works better for you.

With overexposure or underexposure, at some point you are going to get into the toe/shoulder regions of one or more of the emulsion layers. When you do, color balance in that tone would have to change. This has already been stated by other - I think we all agree on principle that under/over exposure can change the color.

Click to expand...

Hi Tim,

Thanks for your kind answer... I think I'd do it just like you said...

One option is getting a neutral base print for each frame, and see where colors fall and how they change: that would be how I'd do it if I had my color enlarger here... (Right now I can wet print B&W only...)

I agree: making a gray card neutral on every shot print, as you say wouldn't represent the real scene's mood or color temperature (and that's precisely what we want to get both on negative and print) but it would help to compare color shifts between frames...

I hope Mark will lend a hand checking the negatives... I asked him because here in Barcelona no pro lab (or any kind of lab) wet prints using color enlargers anymore... All of them scan... If I could ask any lab for wet prints, I think by now I would have no doubt at all about my results... And I explained my lab the test, and what I was looking for, and they know about pro scanning a lot more than I do... And the results for direct sun are normal: one or two stops of overexposure makes the film have better, warmer and more real "as seen" colors... (Greens and shadows suffer a lot at box speed...) But what surprises me, is that with soft light scenes (in the shadows, with their normal cool cast) box speed is clearly warmer than +1, and going beyond that +2 is even colder, so it's inverse...

I'd really like to see another opinion without any digital process involved...

Cheers,

Juan

Juan,

I see also that you are passionate about this, that is good.

No we still don't agree.

I'm going to assume, since you have not answered my question, that the tests you have done are related to scans. Your results are consistent with what I would expect from scans.

There are significant differences in the results between using a scanner and using an enlarger, the process fundamentally different so it is quite tough though to give you a proper answer or opinion without knowing one way or the other.

Don't get me wrong here, I'm not against scanning film or having a lab do it for you; but making us guess about your process is simply bad manners and APUG isn't the right place to discuss the results generated by scanning negatives.

Below I've provided a procedure to check color temp differences using an enlarger. I do this regularly with rolls from my Holga.

Please show us a bit of respect and let us know how you got your results before beating this dead horse anymore.

Juan Valdenebro said:

I have a better idea: maybe you could tell me what would be, from your experience, the best way to compare two differently exposed frames to see if one of them is warmer than the other one... How would you do it? There must be a way you can imagine: a way you'd trust in... Just tell me how you would do it... Stop wondering about the second step (analog or digital)... Any way comes to mind?

Click to expand...

I have essentially explained the procedure already, but here we go again; use your enlarger, choose a single neutral subject in the scene as your reference point, make a good print form one negative, put the next negative in the enlarger and adjust the enlarger exposure to print the reference subject at the same exact brightness on the paper. Repeat this for each different exposure.

Color balance differences can then be judged in the neutrals.

Juan Valdenebro said:

I hope Mark will lend a hand checking the negatives... I asked him because here in Barcelona no pro lab (or any kind of lab) wet prints using color enlargers anymore... All of them scan... If I could ask any lab for wet prints, I think by now I would have no doubt at all about my results... And I explained my lab the test, and what I was looking for, and they know about pro scanning a lot more than I do... And the results for direct sun are normal: one or two stops of overexposure makes the film have better, warmer and more real "as seen" colors... (Greens and shadows suffer a lot at box speed...) But what surprises me, is that with soft light scenes (in the shadows, with their normal cool cast) box speed is clearly warmer than +1, and going beyond that +2 is even colder, so it's inverse...

I'd really like to see another opinion without any digital process involved...

Cheers,

Juan

Click to expand...

Juan,

I guess I can firmly assume from this post that your test results were from the pro lab.

Just FYI, how to deal with a lab is "on topic" at APUG.

I'd be happy to try and print your negatives to show the consistency of temperature.

That won't help you get prints you like from your local labs, all it would prove is that you could get consistent color balance with an enlarger and a wet print.

Basically if you are going to use the local lab you need to learn how to expose for their system.

Differences in density will affect their raw scans.

The other wildcard with labs is how they correct color, they can be tricked.

Shoot a graycard shot on one frame, don't use any filters for that shot.

Shoot the rest of the roll with or with out filters as you see fit.

Have your lab color balance to the gray card shot and use it for the rest of the roll. The rest of the roll will show the effects of your over/under exposure, filters, whatever.

This will take some practice and cooperation from your lab, talk to them about this technique.

markbarendt said:

Have your lab color balance to the gray card shot and use it for the rest of the roll. The rest of the roll will show the effects of your over/under exposure, filters, whatever.

Click to expand...

This is how motion picture is often treated, in 'one-light' transfers. Balanced to the gray card at the beginning of the roll, and the rest is just transferred the same.

markbarendt said:

I'm going to assume, since you have not answered my question, that the tests you have done are related to scans. Don't get me wrong here, I'm not against scanning film or having a lab do it for you; but making us guess about your process is simply bad manners and APUG isn't the right place to discuss the results generated by scanning negatives. Please show us a bit of respect and let us know how you got your results before beating this dead horse anymore.

Click to expand...

Tim, I don't get you wrong, but on previous posts I wrote how I explained the lab my test and what they should look for when scanning... I haven't made APUG guess anything... Apart, even if scanning is not a process discussed on APUG, this thread is not about scanning at all, but just about forum members opinions on COLOR VARIATIONS ON FILM DEPENDING ON PLAIN EXPOSURE: A 100% ANALOG SUBJECT. I kindly invite you again, for the second time because you didn't answer before, to tell us forum members if your opinion on this thread's subject is number 1 or number 2: Opinion 1 is: Exposure below, at, or 1 or 2 stops above box speed, just doesn't change how warm or cool Portra 160 VC render a given scene. They're identical frames: no color shift. No difference ON FILM. Opinion 2 is: Underexposure or overexposure can make Portra 160 VC give slightly different color temperature to a given scene. Even if we can filter on enlarger to make frames look close on print, or for example make a cold scene look warm, certainly I believe there are differences ON FILM... And another thought: I think, and maybe some more people do, a scanner can be used to examine two film frames and find out if they have tonal differences caused by different exposure. I guess there must be ways to do it for a skilled technician dedicated to scan... But for what matters here on APUG, I am waiting on opinions by members who might have found those tonal differences using analog procedures like wet printing. I don't care about the system used as long as it shows my 100% analog (film + different exposure) variations.

markbarendt said:

I'd be happy to try and print your negatives to show the consistency of temperature. That won't help you get prints you like from your local labs, all it would prove is that you could get consistent color balance with an enlarger and a wet print.

Click to expand...

Why do you want to do such thing instead of looking for the truth?... You clearly say you'd “try” to show the consistency of temperature... What if you're wrong and there's no such consistency from -2 to +3? I know -too- how to use both digital and analog ways to make prints that show such pretended consistency, but it doesn't mean that consistency is IN FACT on film frames... Precisely this thread's about finding ways to see REAL FILM BEHAVIOR instead of filtering for similar prints...

markbarendt said:

Basically if you are going to use the local lab you need to learn how to expose for their system.

Click to expand...

We agree here. And that's acomplished after my test done through their scanning and printing. That's why I did it that way with them. But, I want to be sure if wet printing can show me the same results... To be more specific: I want to wet print my best color frame (say a +2 one) including skin, grass and neutral tones (floor) with the natural warm look as the real scene was, and then I want to compare it with the best possible filtering for the frame I consider underexposed (box speed), cool and with horrible greens, to know how they differ after all filtering efforts with analog procedures are done... That's what would speak clearly: those two small wet prints compared... Maybe you get them identical and I'd be very surprised, and then you'd be right and overexposing would not be necessary... I keep my mind open... And thanks for offering your kind help: I think that would be great... I think I should send you a few negatives if you tell me where to send them...

markbarendt said:

Shoot a graycard shot on one frame, don't use any filters for that shot.

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I have done what you say some other times, with studio strobes and models to show real fashion color on neutral light, but I think for this test it's irrelevant... Please allow me to explain why: first I did include grays so I could easily check coolness or warmth as on a gray card... Those grays were the floor and buildings... I already saw changes on them as my prints show... And about using the warming filter or not: it doesn't make any difference in this case, because all the roll was done with the filter on, so if film really has variations, those variations will exist EXACTLY IN THE SAME DEGREE NO MATTER IF A FILTER IS USED OR NOT, because we talk about variations produced by the amount of exposure exclusively.

Mark, I think -as you said- now this thread is kind of a dead horse, and APUG could find interesting your conclusions in a few days if I send you a few negatives and you tell us what you think about film's tone after filtering... Maybe your N and N+2 prints are identical, or maybe you find you prefer one of them... Please tell me where I can send you my negatives... You can write an address here or through my email juanvaldenebro@gmail.com

Thanks!

Cheers,

Juan

Juan,

You are trying to reduce a complex subject into bullet points and asserting that you should be able to check in either scanned or analog manner and get the same result.

Digital and analog checking will get you different results, period.

Discussing the technical bits of digital processes here on APUG is off topic.

If you want tricks on how to deal with your lab, great we can help.

Want to know how to check color balance on an enlarger, I already told you, others can too.

If you want to talk about scanned results and why they are different go to http://www.hybridphoto.com/ or one of the many other sites that talk about scanning film. APUG isn't the place for that.

FWIW

In my experience, using an enlarger, with Portra I get no color balance shift based on negative exposure, that tells me it's not there. When I send it to a lab, I get some differences, but going back to the enlarger shows me again that digital is just different.

The difference is not in the film, it is in the technicalities of the processes.

Please respect our community's culture.

"APUG.ORG is an international community of like minded individuals devoted to traditional (non-digital) photographic processes. We are an active photographic community; our forums contain a highly detailed archive of traditional and historic photographic processes."

markbarendt said:

Juan,

You are trying to reduce a complex subject into bullet points and asserting that you should be able to check in either scanned or analog manner and get the same result. Digital and analog checking will get you different results, period.

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Hi Mark,

I don't think so... If well used, any system reflecting what's ON FILM should be able provide us the same final information: that known as TRUTH. Both systems should agree in what there's on film...

Cheers,

Juan

markbarendt said:

Discussing the technical bits of digital processes here on APUG is off topic. If you want to talk about scanned results and why they are different go to http://www.hybridphoto.com/ or one of the many other sites that talk about scanning film. APUG isn't the place for that.

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Mark,

You're the only one around trying to make this film+exposure 100% analog thread look like a digital discussion. I've told you this several times. I think you already got it: we're talking just about what happens with color ON FILM when light reached film and it went through C-41. Period.

Cheers,

Juan

markbarendt said:

Please respect our community's culture. "APUG.ORG is an international community of like minded individuals devoted to traditional (non-digital) photographic processes. We are an active photographic community; our forums contain a highly detailed archive of traditional and historic photographic processes."

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Mark,

I respect APUG, and this is a serious subject, and I'm a professional photographer long ago... This is a 100% analog thread and I am asking for APUG members opinions based on analog media and procedures. Please respect this thread. If you think I don't respect APUG, get in contact with the Moderators, and they'll contact me or explain this to you...

Cheers,

Juan

Mark,

Weren't you going to print a few of my differently exposed negatives, with identical results on print after filtering? What's your address? Did you change your mind?

Cheers,

Juan

Portra 160vc does have a slight tonal shift. 160nc is much less and maintains shadow neutrality, but 160vc does have a warm shift to it.

Not to worry, though, because this is what makes each of these films unique.

Ken N said:

Portra 160vc does have a slight tonal shift. 160nc is much less and maintains shadow neutrality, but 160vc does have a warm shift to it.

Not to worry, though, because this is what makes each of these films unique.

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Hi Ken,

That's interesting information... Thanks for sharing: I have never used NC... (For natural color I use Astia). I'll remember it in case I use NC...

With VC, more than a shift towards excessive warmth with overexposure, what I can see is that at box speed the film is a bit cooler than real world, and with +1 and +2 under direct sun, 160VC reaches a more natural rendering...

Cheers,

Juan

PM sent with address.