dynamic range of film

Hi everyone.

 

I would just like to inform you about a certain test that Kodak

did on one of their motion picture films (vision 500T 5279).

the test included photgraphing shiny metal spheres that reflect

very bright highlights. The tests confirmed that there were

variations recorded 15.9 stops above 18% gray, which gives film

a dynamic range of about 20 stops.

 

I can't provide you with any links because the tests are described in

some SMPTE documents, which require SMPTE membership.

But here is a link to a post from John Pytlak from kodak that

explains it all.

 

http://www.cinematography.com/forum2004/index.php?showtopic=2649

The dynamic range of print film, especially high lattitude materials like motion picture film or portrait materials like NPS/Reala or Portra NC, is extremely immense. 12-15 stops is the low end of what I've encountered pulling density gradients off of my drum scans from VPS, and doing very long exposure custom prints from badly over-exposed film.

 

The point is: so what? Desktop scanners can't extract all this dynamic range, most minilabs are now scanner based vs optical, those optical based mini-labs are lucky to be accurate with a 2-stop slope with their analog filter tables, and photographic paper can't reproduce the range anyways. Plus, the greater the dynamic range of print film the more muddy it looks because dentisy range remains fixed. This results in narrow color gradients getting compressed and looking fake, much like Reala under over-cast skies. Also, motion picture film is among the most unremarkable of all photographic emulsions, unless you actually like the 'duped down' look with no pure colors or detail.

 

Also, if you talk to Hollywood cinematographers, most bitch about MP film having too much dynamic range vs too little.

Most color negative films can record seperation in detail with scenes that exceed a 150:1 brightness range.However, most color papers used for color negative printing, can only record around a 40:1 brightness range(the blackest black reflects about 1/40th of the light reflected by the whitest white).

 

A properly exposed and processed B&W neg can exceed a 200:1 range, but once again the paper can only record the same 40:1.Of course in B&W work this can be expanded or contracted by varying development, and use of different contrast printing materials.

 

 

Color silde materials also have this same 40:1 limitation in their brightness ranges.

"so what?" Nothing, I just thought that most people belive it to be somewhere about 12 stops. That is why I posted it.

By the way. Motion picture film is as good as still photography negative film. the bad reputation has came from using motion picture film on photo papers. They are made for scanning on MP scanners or

for making prints, nothing else. In their own domain they are as good as all othernegative films.

What you see in cinema is allso not a good reference because you are seeing a print of a dupe.

You should see some scans made on cineon scanners, or at least talk to someone in Hollywood working one one of those machines if you want to judge motion picture film.

Edgar, I'm always fascinated by your posts about cinama film and

movie production. Do you think the 20 stops 500T can record are

more than still films such as NPZ or 400UC can record? And why o why

are Tungsten still films so uncompetitive; I suppose due to lack of

demand.

Why are you fascinated by my posts? I haven't really said anything fascinating, i just try to defend cinematograqphy products because I have seen both sides equally and I can see a lot of prejudgments based on some lousy experiences of misused film in 70's.

 

Since I am not a cinematographer, there is little that I can say

about 5279 other than stuff that I have seen as an observer.

But it is usually known as a contrasty film in cinematography.

It is not used as often today because of the new fast kodak films.

And about the dynamic range of still films, I really have no idea, I just use films, I don't test them. Perhapse you can find out for your self If you can find any data about how much dynamic range do these films you mentioned have.

But I can tell you that 5279 is not the maximum in latitude and dynamic range in cinematography. The new 500T films (vision 5229, and vision expression 5218)are lower contrast films and their dynamic range is even greater. In fact the trend in cinematography is going towards low-contrast linear look that leaves a lot of room for DI work, which is the wave of the future.

 

Tungsten balanced films have always been the standard in cinematography. I belive that first daylight balanced film was introduced in 80's. Today there are only two daylight balanced films from Kodak and eight tungsten balanced films. (ISO 50 and 250)

A text error "(ISO 50 and 250)" part is for the two daylight films I mentioned..

Guys;

 

Look at it this way.

 

You all know that one stop is 0.3 log exposure, and the article claims 13 stops. Ok, 0.3 (log E / stop ) x 13 (stops) = 3.9 log exposure for the range.

 

The average contrast is 0.6 so 0.6 x 3.9 (slope x range) = dmax of 2.34 over fog or mask, or the 'y' axis. (rise x distance)

 

This is certainly within the capability of any common color negative film, as you can see on the EK web site where they post curves.

 

I have posted this before, BTW, and it agrees with what I have said before and is correct. I guess no one believed me before. Maybe you will now. Try a color negative film, it is better than any reversal film for recording the entire brightness range in your scene.

 

Printing onto a duping film gives a far superior transparency as a result. The reason is that dupe films have a higer Dmax than a reversal transparency film giving a higher dynamic range. ECP is an example and the curve is on the EK web site. That is why Hollywood uses color negative. And, you might want to look up my other 'futile' posts on this subject. Maybe if you re-read them it will convince you of the facts.

 

Ron Mowrey

Color slide films and color papers have about the same latitude to record data with but less than ECP due to two different reasons. Color paper does not reveal this range due to multiple internal reflections which limit it to an apparent D-max of 2.0. With proper illumination or by viewing by transmitted light, you can see this detail which is not visible in ordinary illumination. I described an actual experiment in another post for this.

 

Transparency films are limited due to having a D-max of about 3.0 for technical reasons which don't apply to print films which can have a D-max of up to 4.0.

 

Forgot to add this in the previous post.

 

Ron Mowrey

Rowland. we are talking about 20 stops, not 13.

Kodak usually uses 13 stops in their charts, but the actual

dynamic range is off the charts.

 

I wish I had a SMPTE membership to read the full study.

By the way. Hollywood is using negative film because that way they can protect their film from damage caused by high speed printing.

Their negative is printed only a few times, the master positive is printed more times and stays the "access" copy in the future, and

dupe negative (or internegative) is what gets all the beating from high speed printers, It is allso made on ESTAR bases which makes is stronger for that job. Original camera negatives must be acetate based

because they still get cut and spliced phisically without exeption

(at least for cinema releases)

I don't think the standard has to do much with esthetical factors.

E6 is used allso in cinematography (ektachrome, velvia) but mostly for music videos or ads where they want a special saturated look.

Of course Edgar.

 

But, notice the d-max obtained in my example. It is only 2.34. Need I point out that in the published curves by EK, the curve continues upwards, and we know that d-max values of film approach 3.0 above d-min. I was using the example used in the referenced URL and didn't feel that I needed to go through the whole thing for you.

 

In fact, the expected D-max from a film with a latitude of 20 stops is about 3.6, well within the density range capabilities of color negative films.

 

I have routinely made this type of exposure. I have actually made the coatings. I'm fully aware of the capabilities of negative films Edgar.

 

Ron Mowrey

Ok then, I have misunderstood your post.

Edgar;

 

Sorry for being so terse, but I've gotten hyper over this particular subject, I guess. I was roundly criticized the several times I got into this type of discussion when I extolled the virtures of color negative, and then mentioned the quality of motion picture negative films.

 

Also, I really should have been clearer in my first post.

 

Thanks too for bringing this topic up.

 

Ron Mowrey

I know all about your problems, I've been following your discussions about this subject. By the way, it is great to see someone on these boards that is interested in motion picture film, most people have prejudgements about it.

MP films unremarkable? I'll support Edgar here. Sitting in a cinema and watching the fresh first print from a well-exposed camera neg is a magical experience. And it's only the size of half a still frame.

 

Best,

Helen

Actually It is less than half. If you are watching a cinemascope feature then you get 21cm x18cm (this is the maximum surface you get in 35mm cinema) and if you are watching a spherical feature (1.85:1, or 1.66:1) then you get about 21cm x 11-12 cm

and furthermore you are watching a 4th generation image made on fast printers for mass production of prints that don't not even stop from frame to frame to make an exposure (!!)

Instead they just continuously roll both the negative and fresh print film at high speed. Needless to say, there is a lot of room for error and fuzzy images.

Considering all of that I say that film holds amazingly good on screen.

 

But a release print made that way is far from impressive. What is really impressive is a print made from the original camera negative on a step contact printer, or a 70mm blow up print.

Well, most all color negative is capable of that kind of quality. Most cinematographers know how to get the max out of it, but most average still photographers don't.

 

If you notice here, a large percentage of people use transparency film which is generally inferior to negative film in every way.

 

If you want slides, take the original on negative film and make transparencies on print film.

 

Ron Mowrey

Now I wouldn't agree that reversal film is inferior to negative film...

Perhapse it is somewhat lower in resolution, but I belive everything else is comparable and they both have their own unique charms.

Edgar;

 

Given the latitude of reversal vs negative, I think you will concede that this is a point in favor of negative films.

 

Given the ability of negative to print onto print films with that superior tone scale virtually intact and yield superior transparencies, I think you will concede the second point.

 

Given that negative - pos prints can be magnified to theater proportions and transparency films cannot, and that transparency films cannot be duped as well or through as many generations, you will probably concede grain and sharpness as well then.

 

Add to this the more reproducable and controllable process of negative films and the better color correction through masking, I hope you are beginning to see where I'm coming from.

 

I could add more details, but I think I've listed enough. Transparency films are quite good, but negative - positive has the potential to be far superior. Many people use the amateur (consumer) grade of film, and never get dupe positives so that they can make a direct transparency to transparency comparison. I have done that, and the results are stunning. Well, see Helen's comment above. You are getting close to what is seen in a theater.

 

Ron Mowrey

I am just itching to ask: Were black and white movies shot on negatives or positives?

<I>If you notice here, a large percentage of people use transparency film which is generally inferior to negative film in every way</i><P>Good god what a stupid comment.<P>Even an amatuer photographer with a good film scanner can determine the superiority of slide or print film for specific situations. Print film - great stuff, if you have a high brightness range or are shooting in the studio. The superiority of slide film for recording long color gradients under general/low contrast lighting is known by every commercial and digital lab in the free world. Rowland obviously lacks the basic ability to go outside on an overcast day and shoot some scenics with Provia vs his stupid motion picture film and make scans to prove it for himself. Unless you give print/motion picture film a strong brightness range it will produce mushy images, that are bland, muddy, and specifically lack color dimension.<P>The high lattitude of print film benefits wedding photographers, point and shoot cameras, and the mini-lab at Kmart. Given an aethestic choice, it's been shown than strong density range is prefered over lattitude when it comes to a final print. Even the best print films compress strong color gradients to grocery store quality, which is why nature and landscape photographers *don't frikken use print film.* What is of peculiar advantage to print film are typical portrait settings because lighter skin subjects tend to ride in the density rich areas of print film vs the less dense areas of slide film. Hence my example posted here a few years ago using the same subject shot with NPH vs Astia giving the skin tone edge to NPH, but the color detail advantage to an even greater degree to the transparency film.<P>Motion picture film: we've beat this one to death, but the reason Hollywood uses MP film is because it's cheap, easy to process, easy to dupe, and has high lattitude. The stuff is otherwise inferior to short roll, professional print films, or Kodak's marketing dept would be shoving it in cassettes and selling it at 400x mark-up. The Kodak stuff also blocks the piss out of strong colors, which is obvious in any DVD transfer which are frequently made from the master. Even UC 400 will hold detail in areas Kodak's MP film can't, and please don't blame it on the dupe film.<P>If you've see the movie 'Hero' at the theater you'll know what I mean by motion film being crap. This is perhaps the worst film transfer of a major film I've seen in the past 10 years with quality so low I almost walked out of the theater. The Hollywood directors guild should have donated Zhang Yimou a digital MP camera vs having this masterpiece practically destroyed by being shot on film and duped so horribly. I'm hoping the DVD transfer cleans it up.<P>Also, shooting a low density material like print film and trying to expand the tonal range by optically duping on higher density range film does not = slide film. I mean, that's flat out absurd. Optical duping is Fred Flinston technology since even in the early 90's I was using film scanners and recorders to digitally transfer slide scans to print film and print film scans to slide film. Before LightJets hit the scene I'd scan 35mm trannies and make 4x5 digital negs, and then print them on C-type, which almost always produced better results than direct R-type. Once LightJets hit the scene, I was able to make direct prints from the slide, and they were superior to any copy made on neg film.

I was talking about image qualitty only.

Sure the latitude of negative is convenient, but if you look at a transperecy as a finished product, then the latitude does not make any difference. Once you print negative onto a print film you get the same contrast and your latitude is limited just as with a transperecy.

 

Negative is by far a more convenient tool for a photographer or a cinematographer, but I am talking about image quality here.

 

E6 projected in cinema gives the same feeling as an answer print made from the OCN. It does not look inferior. The differences are esthetical (such as a different tone scale, more saturation etc.)

 

Reversal has always had a bad name in cinema because the old reversal films were not E6. With the introduction of 5285 everything changed.

It is stunning.

 

Like I said, talking in general, I do agree that negative film is superior in most ways. But as for image quality, I think the differences are just esthetical (neither is better or worse) and depend on taste.

Oh please, you can't judge motion picture film from a DVD.

Its compressed as hell, and the colors look fake. And it is made from interpositives or dupes, never from original negatives.

I really don't know where did you get the idea that motion picture film is inferior to professional still print film.

Did you ever get in contact with properly scaned MP film?