Page 1 of 8 123 ... LastLast
Results 1 to 10 of 75

Thread: Pulling Slide Film to Increase Its Dynamic Range

  1. #1
    Marco Fantin
    Join Date
    Aug 2014
    Posts
    148

    Pulling Slide Film to Increase Its Dynamic Range

    Hi,

    The high contrast of slide film is both its strength and weakness. It is very easy to lose detail on the highlights: everything that meters above Zone VII is rendered as pure white on most transparency material. I was curious to see if some this detail was recoverable--in other words, if the dynamic range of slide film could be increased somehow. This could be done by under-developing (pulling) the film.

    Information on the topic is very scarce (I found one old youtube video and some vague treads on flickr). Ansel Adams itself in his book "The Negative" dedicated a short paragraph on reversal film, but he wrote the opposite of what I found. He states: <<If development modifications are possible, they will have their primary effect on the low values (higher densities).>>
    Conversely, I found that, as with negative film, the highlight are restrained by under-developing the film. As an afterthought, this is not surprising because the first step of the E-6 process is the development of a negative silver image, that is then reversed. Therefore, the effect of changing development time is the same in both trasnparency and negative film (except for the different contrast of the two media, see below).

    This is what I found in my first experiments. Please compare the two pictures below (both on 4x5 Velvia 50):


    The two images were exposed as indicated above via the zone system, but they were then given different development. The picture with normal development has blown out highlights, and some areas looks too bright. The one that was underdeveloped by half stop shows significantly more details in the highlights. It's not a scientific 1:1 comparison, but I am confident in my metering and I know that without the reduced development, the image on the right would have been too harsh.

    A change in development of half a stop makes quite a large impact to slide film, because its inherent high contrast, as opposed to negative film that has much wider dynamic range (most transparency material records no texture outside Zone II-III and Zone VII, as opposed to Zone II and Zone VIII++ for negative film).

    I made a Youtube video to share my experience on this topic, going a little more in depth. Please let me know if you find something different.
    I am sure that many people use these procedures of development control on a consistent basis, but I could not understand how it worked until I tried it out.



    Some final thoughts and additional information:
    Fuji recommends pulling up to 1/2 stop. So what I have done is not revolutionary. See the manual http://www.fujifilm.com/products/pro..._datasheet.pdf

    The question is why it appears that there is more information in the highlights of Velvia 50 that what is retained after reversing the film, information that can be recovered when under-developing the film.
    I think this is mostly due the color developer bath of the E-6 process: under-developing the film leaves more unreacted silver salts with which the colors can react to.
    Unlike negative film chemistry, in which highly are optical density that linearly builds up with exposure leaving less and less Ag salts, the color developer in E-6 needs a certain amount of unreacted AgBr, a sort of threshold to have minimal density (i.e. texture in the highlights).

    I am a chemist during the day and all this is just fun to think and thinker about for me. If then this reasoning leads to some (minor) artistic improvement of my images, and to some understainding by the readers--this is a nice added bonus.


    I will post more test that compare the same image. Stay tuned if interested.
    Last edited by marcookie; 24-Apr-2019 at 20:03.
    My Youtube Channel - Darkroom and large format tutorials

  2. #2

    Join Date
    Jul 2008
    Posts
    3,901

    Re: Pulling Slide Film to Increase Its Dynamic Range

    Except from Morley Baer's book Wilder shore:
    https://www.jamesgrahambookseller.co...r-shore-signed

    Click image for larger version. 

Name:	Ektachrome_Wilder Shore MB.jpg 
Views:	39 
Size:	145.1 KB 
ID:	190326



    Bernice

  3. #3

    Join Date
    Jul 2016
    Posts
    4,566

    Re: Pulling Slide Film to Increase Its Dynamic Range

    Quote Originally Posted by marcookie View Post
    slide film
    Marco,

    Slide film has more than 4 stops dynamic range, it has at least 6.6 stops.

    See graph 21 in page 8: https://www.fujifilm.com/products/pr..._datasheet.pdf , you have around 2H log exposure dynamic range.

    It is true that you may easily burn highlights, but shadows may have detail well beyond 3.0D. A good scanner may be required to recover those deep shadows.

    If you see the tetenal datasheet you may pull even 3 stops by conserving first development time but decreasing first development temperature to 28.6ºC, https://www.freestylephoto.biz/pdf/p...structions.pdf

    Because of practical precision, Pull is usually done by modifying Temp instead Time.

    If you are interested in that you may find useful learning to calibrate film, this is plotting density vs exposure for different developments, Beyond the Zone System book teaches practical sensitometry knowledge. With reversal process the curve is inverted, but same theory may be applied.

    Regards

  4. #4
    Drew Wiley
    Join Date
    Sep 2008
    Location
    SF Bay area, CA
    Posts
    18,338

    Re: Pulling Slide Film to Increase Its Dynamic Range

    Current slide films "pull" quite poorly. It's pretty much a waste of time. There were some older ones which could handle about half a stop of pull before risk of highlight crossover. The change in pull performance seemed to coincide with newer extremely fine-grained versions of Ektachrome, Provia, etc. I think you will be disappointed, but you can always try. I wouldn't risk anything important. Not much chrome transparency film is left anyway. It remains to see if E100 will be revived in sheets. Those of us who shot chrome films routinely tended to instinctively look for scenes amenable to their inherent contrast range. I was a darkroom color printer, and soon learned that you can get a lot more mileage out of a chrome by learning unsharp masking than by quickie options like pulling or flashing, which tend to have unwanted side effects. In recent years I've switched over to Ektar and RA4 printing, since all my favorite chrome films are now gone, and Cibachrome too. And Pere - Velvia does have quite a bit more sensitized range in the shadows than most people realize, but not much of it is realistically usable. It gets pretty blue and grainy down there. This is a topic where following Zone theory will just get you in trouble. Why? Because color film is exactly that - it involves color, not just a gray scale. Warp that scale, as engineered, and you're likely to distort color reproduction too. I'm not trying to discourage experimentation. It's just that I've been there and done that; quite a bit, in fact.

  5. #5

    Join Date
    Jul 2016
    Posts
    4,566

    Re: Pulling Slide Film to Increase Its Dynamic Range

    Quote Originally Posted by Drew Wiley View Post
    Current slide films "pull" quite poorly.
    Hmmm.... Please read the velvia 50 datasheet, for example, it says "superb push/pull processing" in the first page.

  6. #6

    Join Date
    Dec 2013
    Location
    Nashville
    Posts
    610

    Re: Pulling Slide Film to Increase Its Dynamic Range

    I guess you have a choice: go with what the datasheet says or your own experience.

  7. #7

    Join Date
    Jul 2016
    Posts
    4,566

    Re: Pulling Slide Film to Increase Its Dynamic Range

    I guess fujifilm is very serious in the datasheets.

    I pulled velvia 100 that was accidentally shot at 50 with perfect results.

    So no choice, both personal experience and datasheets tells the same.

  8. #8
    Drew Wiley
    Join Date
    Sep 2008
    Location
    SF Bay area, CA
    Posts
    18,338

    Re: Pulling Slide Film to Increase Its Dynamic Range

    I don't believe it. Most of the Velvia shots you've previously posted look awfully fake color to me. That's fine if it's the creative effect you're after. But if you did methodical testing with calibrated color standards, you'd discover the difference. Old original Velvia 50 would handle about half a stop. That's it; then crossover. The newer 100 stuff, naah. Like I said, been there, done that. Morley Baer's Wilder Shore work was done on Ektachrome 64. I've seen the actual prints, not just the book. He overexposed it and then had it pulled for a slightly washed out look. The Museum director didn't consider it worthy of arts exhibit space, so hung the prints in the natural sciences section. Whatever. Morley got canonized posthumously. At that time he was noted as an architectural photographer, primarily for his deadpan colorful facades of hippified SF Victorians published in Painted Ladies. With the Wilder Shore project he took the opposite tack. And good ole overtly blue Ektachrome 64 was a lot more flexible pulling than the snappier Fujichrome 50 that soon showed up. The first two generation of Provia sheet film pulled the best of them all. Once it went to the current fine grain, that ended. Most push better than they pull. I managed to get a lot of Fuji 8x10 film remarkably cheaply and did lots of experiments with all of them. Velvia is about the worst choice possible if excessive contrast is your worry. I don't understand its popularity unless you're doing a slide show. There is a select suite of hues it does better than other films; and I selected it for that kind of use, as well as when I actually wanted a boost in contrast.
    But when it comes to printmaking, versatile it ain't.

  9. #9

    Join Date
    Dec 2013
    Location
    Nashville
    Posts
    610

    Re: Pulling Slide Film to Increase Its Dynamic Range

    Quote Originally Posted by Pere Casals View Post
    I guess fujifilm is very serious in the datasheets.

    I pulled velvia 100 that was accidentally shot at 50 with perfect results.

    So no choice, both personal experience and datasheets tells the same.
    Which E6 kit did you use?

  10. #10
    Drew Wiley
    Join Date
    Sep 2008
    Location
    SF Bay area, CA
    Posts
    18,338

    Re: Pulling Slide Film to Increase Its Dynamic Range

    Incidentally, I got good enough at predicting would go wrong to deliberately induce certain kinds of crossover using excessive pull. But that was for sake of creative rather than objective results. It's fine to break rules if it serves a purpose.

Similar Threads

  1. does a color negative have the same dynamic range as a regular b&w film negative?
    By dede95064 in forum Darkroom: Film, Processing & Printing
    Replies: 12
    Last Post: 20-Jan-2010, 10:40
  2. What does Dynamic Range Mean?
    By Michael Heald in forum On Photography
    Replies: 3
    Last Post: 23-Dec-2007, 04:01
  3. B&W Film Dynamic Range
    By marschp in forum Style & Technique
    Replies: 55
    Last Post: 8-Sep-2007, 10:22
  4. dynamic range vs 'dynamic range'
    By jonpiper in forum Darkroom: Film, Processing & Printing
    Replies: 8
    Last Post: 21-Oct-2005, 01:39
  5. Dynamic Range with Azo, Pt/Pd, etc
    By Ken Lee in forum Darkroom: Film, Processing & Printing
    Replies: 3
    Last Post: 18-Jun-2005, 13:12

Bookmarks

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •