Kodak EXR vs Vision Sharpness

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koraks

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Y'know, I'm really starting to think photography was a miracle in the first place....

Not just one. If you think about it, it's a whole slew of miracles knitted together into a magical blanket.

"Back"? But the rehalogenating bleach brings those halogens with it, right?

Yes, by "back" I meant that the silver once was a silver halide, then metallic silver, and then it's turned 'back' into a silver halide. But the original halide is gone and replaced with a new halide from the bleach.

do emulsions need to be cut (as in the traditional noodle + wash steps)

No. There's a funny moment when we were walking through the Fuji factory that makes color paper and one of our group members asked "so where do you do the noodling?" The engineer who toured us looked puzzled (I guess he thought for a moment she was making an inappropriate remark about things the factory workers may do during overtime, LOL!) In reality, they don't do any noodling & washing in commercial film & paper making, at least not on the Fuji/Kodak (and I assume Harman) scale. Instead, the quantities of the different chemicals are accurately determined and controlled. In home-style emulsion making, you can 'noodle' and wash an emulsion to get rid of the excess halides, but if you don't add this excess in the first place and ensure that all silver (nitrate) and bromides/chlorides/iodides find each other, there's nothing that needs to be washed out.

or is that merely increasing surface area and it would work in other ways?

Silver halide crystal surface area and geometry are mostly controlled by the ripening process and parameters such as time, agitation/stirring and temperature. It's a bit like making chocolate, where you also need a fairly well-controlled process to ensure that the chocolate has a nice consistency and doesn't become chunky/granular.

But won't that get washed out immediately upon development?

Everything in a photographic emulsion is intended to stay put, and due to the solubility of the materials chosen, they in fact do. The silver halides are all virtually insoluble in water. The dye couplers are in fact oily substances that are present in the form of tiny little globules interspersed with the gelatin strands. The gelatin itself is almost a magical substance in the sense that it can repeatedly soak up water and dry again, it's a mesh structure that becomes more open (allowing chemicals to travel through it) when swollen, it quit selectively traps the oily dye globules while allowing developer to pass through, it's resilient to both low and high pH without altering its structure too much, and of course it can be first melted (actually dissolved) at a reasonable temperature and after chemical hardening, it won't melt anymore, which is very convenient in the manufacturing process. Gelatin is such an underrated material!

Bleach is a bit of a confusing name

Yes, I agree. "Silver oxidizer" would be more appropriate.

are you not personally concerned with doing any experiments with motion picture negative but developing in C41? Or do you have ECN2 chemicals?

I've processed ECN2 Vision3 film in both C41 developer and ECN2 developer. I find the colors are best for me, personally (i.e. more accurate/true to life) in ECN2 developer. ECN2 developer is very easy to make at home and requires only a handful of chemicals, all of which these days are easy to obtain in most parts of the world. The only 'outlandish' one is CD3, which can be had off of eBay and several other channels in reasonable home-user quantities.

Thank you again for your patience with all my questions!

You're very welcome! I hope I'm able to answer them satisfactorily and that someone(s) may chime in where I drop the ball!
 
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Crysist

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Not just one. If you think about it, it's a whole slew of miracles knitted together into a magical blanket.
Maybe the first miracle was the hardest, all future miracles must be measured against the first! I saw a chart (on the main author of formate sensitization fame's site) which plotted relative sensitivities of emulsions from Niepce to Daguerreotypes to Collodion to Gelatin and each new sensitizer's effect through time. The 100-1000x jumps in sensitivity are crazy to imagine from where we are now, with emulsions optimized to such a degree that even 4x would have a massive effect. In fact, the allure of producing more stable silver reductions than incident photons was the coolest part about formate.

Imagine if we discover something that works so well we'd need to supersede the "supersensitizer" term and call it a "hypersensitizer".

On that note, are photographic processes that expose and are sensitive to such degrees that the exposure, the latent image, produces enough silver that all you need to stop and fix the one's people refer to as "printing out"? Or do I have that term confused with something else?

Yes, by "back" I meant that the silver once was a silver halide, then metallic silver, and then it's turned 'back' into a silver halide. But the original halide is gone and replaced with a new halide from the bleach.
I see!

No. There's a funny moment when we were walking through the Fuji factory that makes color paper and one of our group members asked "so where do you do the noodling?" The engineer who toured us looked puzzled (I guess he thought for a moment she was making an inappropriate remark about things the factory workers may do during overtime, LOL!) In reality, they don't do any noodling & washing in commercial film & paper making, at least not on the Fuji/Kodak (and I assume Harman) scale. Instead, the quantities of the different chemicals are accurately determined and controlled. In home-style emulsion making, you can 'noodle' and wash an emulsion to get rid of the excess halides, but if you don't add this excess in the first place and ensure that all silver (nitrate) and bromides/chlorides/iodides find each other, there's nothing that needs to be washed out.
Right, plus that'd be a waste of resources and of another step at that scale.

But when you say "nothing needs to be washed out", how can that be? Commonly, you mix AgNO3 and some halide salt KX or NaX. Doesn't a double replacement reaction occur? For all the AgX you make, you also get as much Na/KNO3. Is that not what you need to wash out? It doesn't seem like you can avoid it. Do you mean excess AgNO3 and excess Na/KX get washed out in the wash step of emulsion making? Is the Na/KNO3 fine to keep in the emulsion?

Silver halide crystal surface area and geometry are mostly controlled by the ripening process and parameters such as time, agitation/stirring and temperature. It's a bit like making chocolate, where you also need a fairly well-controlled process to ensure that the chocolate has a nice consistency and doesn't become chunky/granular.
Sorry I was a unclear, I was talking about the noodle process. I was asking if noodling was necessary solely to increase the surface area for the emulsion to be washed easier or quicker and was otherwise not strictly necessary.

But thanks for the comparison, I guess it works with any process that can be seeded by small flecks that could grow a lot, like a saturated sugar solution crystallizing. One thing I'm curious about is what some commercially available gelatin emulsions are like. I've seen the Photographer's Formulary one, there's and Ilford one, I believe Rollei makes some, etc. Grain size, proportion of halides, etc. I saw some good resources for how the balance of bromides and iodides affect sensitivity in collodion, are they comparable? Besides the sulfur in gelatin helping.

I think I have a bizarre interest in what the different combinations do and what's possible with them. 3 layers of different sensitivities common in modern films per color layer, but why not 4? 5? MORE? Will that give us the coveted 30 stop dynamic range? HAVE FUN PRINTING!

How small can the grain size be made? Lippmann and holographic emulsions get them ultra small, do they just not heat the beaker up at all, or could they go smaller? Less time, mix the solution colder? Hmmm. I should probably make a post on the emulsion making forum about these things.

Everything in a photographic emulsion is intended to stay put, and due to the solubility of the materials chosen, they in fact do. The silver halides are all virtually insoluble in water. The dye couplers are in fact oily substances that are present in the form of tiny little globules interspersed with the gelatin strands. The gelatin itself is almost a magical substance in the sense that it can repeatedly soak up water and dry again, it's a mesh structure that becomes more open (allowing chemicals to travel through it) when swollen, it quit selectively traps the oily dye globules while allowing developer to pass through, it's resilient to both low and high pH without altering its structure too much, and of course it can be first melted (actually dissolved) at a reasonable temperature and after chemical hardening, it won't melt anymore, which is very convenient in the manufacturing process. Gelatin is such an underrated material!
Sorry, I was referring to the "washable byproducts" again.

That aspect of gelatin is super fascinating. I can also see why it is confusing to others (there was this thread about reticulation causing image shifts or something that went on and on...), but it's stability is truly amazing. I mean, sometimes I wonder "wait, why aren't the silver halides just falling out?".

I suppose the structure of the "mesh" is on the molecular level. It probably wouldn't even be a problem for the finest Lippmann emulsion. And hardening makes me think it turns into a rock, despite still being on a very flexible film and still being permeable!

I've processed ECN2 Vision3 film in both C41 developer and ECN2 developer. I find the colors are best for me, personally (i.e. more accurate/true to life) in ECN2 developer. ECN2 developer is very easy to make at home and requires only a handful of chemicals, all of which these days are easy to obtain in most parts of the world. The only 'outlandish' one is CD3, which can be had off of eBay and several other channels in reasonable home-user quantities.
It is? I thought it was considered harder. Maybe it's just because it's a whole separate process from C41.

Regardless, that 250D article was totally awesome!

You're very welcome! I hope I'm able to answer them satisfactorily and that someone(s) may chime in where I drop the ball!
Thanks a bunch! I don't mean to throw you so many questions though, haha! Just trying to wrap my head around some parts I'm still fuzzy over or otherwise interested in!
 

koraks

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On that note, are photographic processes that expose and are sensitive to such degrees that the exposure, the latent image, produces enough silver that all you need to stop and fix the one's people refer to as "printing out"? Or do I have that term confused with something else?

A "print out paper" is indeed a photographic paper that forms the entire image through exposure. It does not require any development; only fixing and washing, at least in the case of silver halide papers. There are print-out processes using other chemistry that may require only washing, no fixing; cyanotype is a popular one. What these processes have in common is that they require A LOT of exposure to form an image.

Is the Na/KNO3 fine to keep in the emulsion?

You may want to refer to a more knowledgeable emulsion scientist on this, but yes, as I understand the additional NaNO3 and KNO3 that exists as a byproduct of the AgNO3 --> AgX reaction remains in place and doesn't interfere with the further photographic processes. Since they're soluble compounds, they should wash out on first contact with water. The film and paper making processes don't involve any wet steps after coating, so it must happen only when the paper/film hits the developer or pre-rinse.

I was asking if noodling was necessary solely to increase the surface area for the emulsion to be washed easier or quicker and was otherwise not strictly necessary.

I see; sorry, I misunderstood. Yes, I think you're correct and the noodling is only done to make the wash faster. Washing a solid block of swollen gelatin would probably take days or weeks since the diffusion would be so slow.

I saw some good resources for how the balance of bromides and iodides affect sensitivity in collodion, are they comparable?

I don't know how the commercially available "brush your own" silver gelatin gelatin emulsions compare to wet plate in terms of speed. I'd expect they're in a similar league, give or take an order of magnitude

How small can the grain size be made?

The smallest would be a single conglomerate of one silver ion and one halide ion. A bit like colloidal silver, but in AgX form. I guesstimate the size would be in the order of 50-100A (0.05-0.1nm) or so, given that a single gold atom is something like 100A or so. I don't know how easy or difficult it is to make these unconglomerated silver halides. For instance, when making salt prints, which basically involves forming silver chloride in situ on the paper by consecutively coating sodium chloride and silver nitrate on it, I don't know if any clustering/crystallization really takes place. I wouldn't be surprised if this is exactly what you describe: singular AgX-es. Just a lot of them all bunched together.

It is? I thought it was considered harder. Maybe it's just because it's a whole separate process from C41.

ECN2 developer is even simpler than C41 developer, and even C41 developer is fairly straightforward to make. There are various recipes online, including on Photrio, and I've collected a few on my blog as well. The main 'challenge' is that they call for minute amounts of potassium iodide which may be somewhat challenging to dose precisely when making small batches. When making my own C41 developers, I saw small differences between my conconctions and commercial FujiFilm chemistry. I never really looked into it very deeply; the differences were small to the point of negligible for my own purposes. I choose to use the Fuji stuff because it's convenient, reliable, keeps very well and basically it's just a whole lot easier than weighing out stuff myself. But ECN2 is so simple to make and I've got all the ingredients anyway, so I prefer to make that myself.
 
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Crysist

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Sorry for not responding so soon!! I appreciate your responses!

A "print out paper" is indeed a photographic paper that forms the entire image through exposure. It does not require any development; only fixing and washing, at least in the case of silver halide papers. There are print-out processes using other chemistry that may require only washing, no fixing; cyanotype is a popular one. What these processes have in common is that they require A LOT of exposure to form an image.
Ah, is that more a trait of certain processes or is it a certain class which has its own benefits?

You may want to refer to a more knowledgeable emulsion scientist on this, but yes, as I understand the additional NaNO3 and KNO3 that exists as a byproduct of the AgNO3 --> AgX reaction remains in place and doesn't interfere with the further photographic processes. Since they're soluble compounds, they should wash out on first contact with water. The film and paper making processes don't involve any wet steps after coating, so it must happen only when the paper/film hits the developer or pre-rinse.
I see, that makes sense!

I see; sorry, I misunderstood. Yes, I think you're correct and the noodling is only done to make the wash faster. Washing a solid block of swollen gelatin would probably take days or weeks since the diffusion would be so slow.
Got it!

I don't know how the commercially available "brush your own" silver gelatin gelatin emulsions compare to wet plate in terms of speed. I'd expect they're in a similar league, give or take an order of magnitude
I'll have to add them to my "to do" list of things to try!

The smallest would be a single conglomerate of one silver ion and one halide ion. A bit like colloidal silver, but in AgX form. I guesstimate the size would be in the order of 50-100A (0.05-0.1nm) or so, given that a single gold atom is something like 100A or so. I don't know how easy or difficult it is to make these unconglomerated silver halides. For instance, when making salt prints, which basically involves forming silver chloride in situ on the paper by consecutively coating sodium chloride and silver nitrate on it, I don't know if any clustering/crystallization really takes place. I wouldn't be surprised if this is exactly what you describe: singular AgX-es. Just a lot of them all bunched together.
Right, I've seen some of these figures used on a more theoretical basis but didn't know, between how the crystals are dispersed and layered with crystals of differing sizes, how much it neatly corresponds to a resolving power. For example, a crystal might be a bit smaller than when you can have those crystals "record" contrasts.

ECN2 developer is even simpler than C41 developer, and even C41 developer is fairly straightforward to make. There are various recipes online, including on Photrio, and I've collected a few on my blog as well. The main 'challenge' is that they call for minute amounts of potassium iodide which may be somewhat challenging to dose precisely when making small batches. When making my own C41 developers, I saw small differences between my conconctions and commercial FujiFilm chemistry. I never really looked into it very deeply; the differences were small to the point of negligible for my own purposes. I choose to use the Fuji stuff because it's convenient, reliable, keeps very well and basically it's just a whole lot easier than weighing out stuff myself. But ECN2 is so simple to make and I've got all the ingredients anyway, so I prefer to make that myself.
Oh cool! I was mainly concerned if it added some other steps or conditions. Besides remjet removal, I guess that's the big one.

You have ALL the ingredients? I know I have an interest in this stuff and intend to mess around with it, but some people really seem like they keep a bunch of compounds like a well-stocked spice cabinet lol

Thanks for all your help, koraks!
 

srb383

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I've skimmed through this discussion so forgive me if some of these points have already been stated but to offer some potential insight.

Kodak Vision compared to the previous Kodak EXR stock primarily saw an improvement in sharpness for the cyan dye layer (red sensitive layer), aside from that they're mostly the same. But it must be noted that you can't trust all published stock specifications, the published specifications are a "customer aim" and in some cases smoke and mirrors. For example, below are the published MTF plots between EXR 500T 5298 and Kodak Vision 500T 5279. You'll see ridiculously high acutance for 5279.

unnamed (2).png
unnamed (3).png


For comparison, below are real lab tests from a coating engineer at Kodak between 5298 and 5279 when they were in production. Modulation for 5279 and 5298 were in fact equivalent for the yellow and magenta layers, with improved sharpness for the cyan layer of 5279.

unnamed (4).png


And for further confirmation, below are controlled tests of Macbeth charts for 5298 and 5279 from Kodak back in the late 90s, scanned back (downsampled to full hd).

5298.jpg
5279.jpg


John Sawyer employed more tabular grains in 5279 than 5298 (which utilized more polymorphic grains), this of course means decreased scattering in the emulsion during exposure. If you pay attention to the edges of various patches, you'll see greater density for both stock. This is due to development inhibitor archimeric releasing couplers, during development there is more oxidized color developer where density is formed near where density is not being formed (edges), this allows the DIAR couplers to further increase development for those areas and is the reason why modulation in various stock MTF specifications exceeds 100% for mid to low spatial frequencies. It's essentially equivalent to an unsharp mask. But keep in mind, since this takes place in development, the latent image captured prior still contains a resolution which is the product of the emulsions scattering and halation properties, meaning these DIAR couplers improve acutance of a lower resolution latent image.

For later Vision2 and Vision3 materials, scattering between all layers were improved and the impact of these DIAR couplers were reduced, flattening modulation for low and mid spatial frequencies because modern digital scanners didn’t require the boost in that region but needed increased sharpness out beyond 35 cycles/mm. The impact of the DIAR couplers in earlier Vision and EXR stocks were originally intended to compensate for the acutance lost in traditional contact printing across various generations.
 
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koraks

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You have ALL the ingredients?

Sorry, I missed this or somehow forgot about it. No, I don't have the antifoggant so I simply leave it out. Seems to work OK.

@srb383 this is really interesting, in particular the bit about DIAR couplers which explains the changes in acutance between the product generations!
 

RalphLambrecht

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I had seen David Mullen cited as saying "...the contrast has gone down with each generation (EXR, Vision, Vision-2)" in a video essay, so I went to check these stocks out. I had heard elsewhere that they had a very coveted look due to their rendition in various ways, as well as having super fine grain. But looking at the EXR technical data, I found something I didn't expect. The MTF values for EXR are REALLY high compared to later stocks. Why is that? They seem to be nearly twice as good, they're at least touching 200 cycles/mm when they stopped plotting the charts.

Does this relate to having better latitude, did the Vision line trade sharpness for latitude? Is it because of the reduced contrast? Are the charts even right? I've been confused by this for 2 weeks.

please post a copy of the chart for usto evaluate.
 
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Crysist

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I've skimmed through this discussion so forgive me if some of these points have already been stated but to offer some potential insight.

Kodak Vision compared to the previous Kodak EXR stock primarily saw an improvement in sharpness for the cyan dye layer (red sensitive layer), aside from that they're mostly the same. But it must be noted that you can't trust all published stock specifications, the published specifications are a "customer aim" and in some cases smoke and mirrors. For example, below are the published MTF plots between EXR 500T 5298 and Kodak Vision 500T 5279. You'll see ridiculously high acutance for 5279.

-images-

For comparison, below are real lab tests from a coating engineer at Kodak between 5298 and 5279 when they were in production. Modulation for 5279 and 5298 were in fact equivalent for the yellow and magenta layers, with improved sharpness for the cyan layer of 5279.

-images-
Wow, that's a bunch for the elaborate reply! I was surprised to get a notification that someone was replying after this thread went dormant, heh!

That's true, comparing the Vision 500T gives you a similarly wacky result with the gigantic accutance bump. However, it's not out of line with the other EXRs, rather it seems out of line with the subsequent Vision stocks in the line. But, from the other lab test you showed, it seems to differ from the values on the 5279 tech document while the 5298 seems to agree.

What does this mean? Was the Vision 500T 5279 MTF improperly drawn on the technical document? Then what does that mean for the EXR stocks? They seem to mostly agree with each other, extending far without the giant boost.

50D: EXR_50D.PNG 200T: EXR_200T.PNG

It's strange they sometimes have the plots with bounds that are way too far for the data... I tried emailing someone about it because I noticed a bunch of errors on their sellsheets and tech docs but I had no idea who to contact.

My main interest was about the lower-speed EXR stocks hitting far higher contrasts at/around 100 cycles than the Vision2 stocks and onward. They aren't even measured past 72, it seems. They hit appreciable contrasts at 200 cycles that the Vision3 stocks are hovering around at only 70-100 cycles!

And for further confirmation, below are controlled tests of Macbeth charts for 5298 and 5279 from Kodak back in the late 90s, scanned back (downsampled to full hd).

-images-

John Sawyer employed more tabular grains in 5279 than 5298 (which utilized more polymorphic grains), this of course means decreased scattering in the emulsion during exposure. If you pay attention to the edges of various patches, you'll see greater density for both stock. This is due to development inhibitor archimeric releasing couplers, during development there is more oxidized color developer where density is formed near where density is not being formed (edges), this allows the DIAR couplers to further increase development for those areas and is the reason why modulation in various stock MTF specifications exceeds 100% for mid to low spatial frequencies. It's essentially equivalent to an unsharp mask. But keep in mind, since this takes place in development, the latent image captured prior still contains a resolution which is the product of the emulsions scattering and halation properties, meaning these DIAR couplers improve acutance of a lower resolution latent image.
Was John Sawyer one of the designers? Hm, from your images the effect looks a bit more subtle than I've seen in other stocks that have this edge-sharpening-development effect.

It stands to reason that reducing the scattering would improve these performance, then I imagine at some level the DIAR would become overwhelming. Funnily, I don't see it so heavily in that example! Because I have seen those edge-effects on photos though they're usually in B&W cases.

But, it's good that you introduce color charts because I was curious if low-contrast performance would be better visible on transitions between different colors than small grayscale changes.

For later Vision2 and Vision3 materials, scattering between all layers were improved and the impact of these DIAR couplers were reduced, flattening modulation for low and mid spatial frequencies because modern digital scanners didn’t require the boost in that region but needed increased sharpness out beyond 35 cycles/mm. The impact of the DIAR couplers in earlier Vision and EXR stocks were originally intended to compensate for the acutance lost in traditional contact printing across various generations.
Yes, those bumps seem to be outliers currently, except for slide films. Still, the original Vision 500T seems to itself be an outlier for that DIAR effect at lower frequencies. None of the EXR stocks seem to have that dramatic bump, they seem to be more similarly flat to Vision 2 and 3 than the 500T.

Sorry, I missed this or somehow forgot about it. No, I don't have the antifoggant so I simply leave it out. Seems to work OK.

@srb383 this is really interesting, in particular the bit about DIAR couplers which explains the changes in acutance between the product generations!
No worries, it wasn't too important, I just get surprised how stocked up some people are! The homebrew-equse aspect to formulating different developers/etc is too cool! It's motivating!!! I'm going to make my bathroom smell so strange

...

wait, not like that-
please post a copy of the chart for usto evaluate.
Only when reviewing all the different versions do I get an idea of how chaotic things were. Stocks being introduces then discontinued after less than 2 years. Both lines being present at the same time (there's no Vision 50D, but there is Vision2)

Here is a jumble of them (attached), please note each by the filename. So I'll include some odd ones. The EXR 500T is plotted differently, I suppose because it is the oldest technical document that was not revised to the new style. Mostly 50D and 500T:
EXR 50D: EXR_50D.PNG

EXR 200T: EXR_200T.PNG

EXR 500T: EXR_500T.PNG

Vision 500T (5279): Vision_500T_5279.PNG

Vision2 50D: Vision2_50D.PNG

Vision2 500T: Vision2_500T.PNG

Vision3 50D: Vision3_50D.PNG

Vision3 500T: Vision3_500T.PNG

The source of these docs is Tim Gray's archive to the Kodak Technical Docs.
 

srb383

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My main interest was about the lower-speed EXR stocks hitting far higher contrasts at/around 100 cycles than the Vision2 stocks and onward. They aren't even measured past 72, it seems. They hit appreciable contrasts at 200 cycles that the Vision3 stocks are hovering around at only 70-100 cycles!

Interesting. I know the sensitometer at Kodak Rochester for testing MTF exposes the film with line pairs between 2 cycles/mm to 100 cycles/mm, so modulation past 100 cycles/mm for those EXR plots would be extrapolated. As mentioned prior, stock specifications published by Kodak are "customer aims", I can't say for sure what the history is for those extreme cases like the MTF plot for Vision 500T, but I would assume clash between the marketing department or aims from earlier in development that never came to fruition.

The customer aims are typically cleaned up for publishing, not via averaging multiple samples but by artistically making the plots smoother, you can also see this for characteristic curves. I've ran heaps of ecn-2 control strips for Vision3 stock and have never seen results as clean as the published characteristic curves, from lab tests I've seen from Kodak, neither have they. So in general, take the spec sheets with a grain of salt, if you're looking for accuracy you'd be better off to contact one of the engineers for historical records.

Was John Sawyer one of the designers? Hm, from your images the effect looks a bit more subtle than I've seen in other stocks that have this edge-sharpening-development effect.

Yeah, here's the original demo from John when they introduced the first line of Vision stock. Hope this helps.

 
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Crysist

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Sorry for sitting on this for a while!

Interesting. I know the sensitometer at Kodak Rochester for testing MTF exposes the film with line pairs between 2 cycles/mm to 100 cycles/mm, so modulation past 100 cycles/mm for those EXR plots would be extrapolated. As mentioned prior, stock specifications published by Kodak are "customer aims", I can't say for sure what the history is for those extreme cases like the MTF plot for Vision 500T, but I would assume clash between the marketing department or aims from earlier in development that never came to fruition.

Hm, that's interesting. There are quite a few other stocks (such as B&W stocks) that have been measured past 100 cycles. Would all of these have been extrapolated?

And if these figures are showing themselves to be unreliable, what's causing it and what can we concretely deduce at all? Do I just need to buy some leftover EXR stock and confirm it for myself?

The customer aims are typically cleaned up for publishing, not via averaging multiple samples but by artistically making the plots smoother, you can also see this for characteristic curves. I've ran heaps of ecn-2 control strips for Vision3 stock and have never seen results as clean as the published characteristic curves, from lab tests I've seen from Kodak, neither have they. So in general, take the spec sheets with a grain of salt, if you're looking for accuracy you'd be better off to contact one of the engineers for historical records.

Something like the H-D plots being tweaked makes some sense, but I can only imagine that this occurs to only some degree. Smoothing the plots out and the plots arbitrarily implying twice the performance are very different changes to be made by the editorial department in charge of making the technical datasheets.

Just curious, what results do you typically see in your tests?

Also, what are you referencing for the results of Kodak's internals tests, their instruments, techniques, etc? Is there some reference for this stuff? Do you know someone?

Now I'm curious how to get in contact with an engineer at Kodak.

Yeah, here's the original demo from John when they introduced the first line of Vision stock. Hope this helps.



Thanks a bunch for this! I feel some of the differences are difficult to distinguish from the print, though... For example, even watching the 4k stream I don't see a particularly noticeable improvement in grain and only a miniscule difference in the sharpness test. Either my monitor isn't showing it too well or the differences have been lost in making the print and the subsequent scan of that print.

Anyway, film prints looks so pretty...
 
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