Page 1 of 2 12 LastLast
Results 1 to 10 of 19

Thread: Dynamic Range of Portra and Ektar (for the Sekonic L758)

  1. #1
    gmfotografie's Avatar
    Join Date
    Jan 2013
    Location
    Austria
    Posts
    138

    Dynamic Range of Portra and Ektar (for the Sekonic L758)

    Hi, im just try to set up my sekonic for those films.
    for a the display... can anyone tell me (round about) the dynamic range for ektar 100 and portra 160.

    (usually i meassure the darks and put them on zone iii and let the higlights go... never mind exactly where to put the higlights...;-) )

    thank you ;-)

  2. #2

    Re: Dynamic Range of Portra and Ektar (for the Sekonic L758)

    Whatever they are, they are HUGE.

  3. #3
    jp's Avatar
    Join Date
    May 2009
    Location
    Maine
    Posts
    4,510

    Re: Dynamic Range of Portra and Ektar (for the Sekonic L758)

    It's big, I just expose adequately for the shadows and not worry about highlights. The range is probably comparable with tmax 400 based on seat of the pants estimation.

  4. #4
    Drew Wiley
    Join Date
    Sep 2008
    Location
    SF Bay area, CA
    Posts
    10,591

    Re: Dynamic Range of Portra and Ektar (for the Sekonic L758)

    They aren't necessarily generically huge latitudes by any means, at least if you expect quality results. Ektar has just about one stop of margin either side of what you get with a typical chrome film (not Velvia). Beyond this you risk crossover or other issues. Therefore placing shadow detail on Zone III is a good idea; but you can still blow out the highlights in high contrast scenes. If you expose Ektar with as much care as you do a chrome, you'll do fine, except in the sense of color balance in shadows, which is a slightly different subject requiring suitable color temp filtration at the time of exposure (it's a myth all this can be post-corrected in
    PS). Porta films are a lot more forgiving, but a different softer look, with Portra 400 having more snap than 160.

  5. #5
    gmfotografie's Avatar
    Join Date
    Jan 2013
    Location
    Austria
    Posts
    138

    Re: Dynamic Range of Portra and Ektar (for the Sekonic L758)

    thank you all
    ...and let the highlights go
    is not really correct.

    i usually messure the overall contrast and if it is about 5 to 7 stops, i dont calculate where the higlights will go... just put the darks on zone 2 or 3 and basta ;-)
    so therefore i feel ok using the portra. i photographed only 4 sheets with portra with good results...outdoors.

    im generelly not experienced in shooting indoors ;-)
    never have done this before with film.....and tomorrow i will be in a nuclear power plant ;-)
    hope to get some good results... will show it to you if its okay!

  6. #6

    Join Date
    Jul 2012
    Location
    Michigan
    Posts
    101

    Re: Dynamic Range of Portra and Ektar (for the Sekonic L758)

    This image is on 120 film Ektar 100 taken early morning
    https://app.box.com/s/mbi6jx0kykx6ga1h6as30l1xibslqy2n
    It was scanned using Pacific Image PrimeFilmPro120 to a 16 bit tiff
    Dynamic range from the dark car hood to the blue sky in Hex is approximately 0035h to F785h

    That is a ratio (in decimal) of 1:1195

    In decibel: 20log(1195) = 61.5 dB

    in "D" units ( I think the old film dynamic range units) : 3.07

    That dynamic range won't be observable unless a TrueColor ( 10 bit) monitor is used, and a 16 bit tiff is viewed in a 16 bit viewer

    Edit ( forgot) In "stops" that is approximately 6 stops.

  7. #7
    Drew Wiley
    Join Date
    Sep 2008
    Location
    SF Bay area, CA
    Posts
    10,591

    Re: Dynamic Range of Portra and Ektar (for the Sekonic L758)

    Well, my office monitor is not the greatest, but even here it's apparent you've got a thud in all the lower zones due to color balance issues. Next time try an 81A
    filter over that kind of shot. Sure, you can post-tweak it a bit, but it will be hell to get clean hues over the whole range unless you get it right at the time of the
    exposure itself. Once there's dirt in the shadows, it's tricky to get it out. Or just switch to one of the Portra products instead. It's a tradeoff. I know... I know. "Looks fine to me". That's because people are just expecting Ektar to look like yet another color neg film. It isn't. That's like driving a Porsche with a temporary
    spare on one of the wheels. It's a performance film. Portra (esp 160) is more of a classic portrait film, engineered for "pleasing skintones" instead of overall
    color saturation. These are all excellent products, but with very different personalities.

  8. #8

    Join Date
    Jul 2012
    Location
    Michigan
    Posts
    101

    Re: Dynamic Range of Portra and Ektar (for the Sekonic L758)

    Thanks Drew.
    Did you mean that an 81A filter would have helped the early morning color cast?
    I have not used filters so far . I see the 81A effectively reduces the color temp by attenuating the blue range

    Here is one using Porta 160 in bright daylight. Sand stone in Sydney. Graflex 2x3 with the Graftar 103mm
    https://app.box.com/s/guawvk0g2ods4g0xlms00t42pvyrpovl

  9. #9
    gmfotografie's Avatar
    Join Date
    Jan 2013
    Location
    Austria
    Posts
    138

    Re: Dynamic Range of Portra and Ektar (for the Sekonic L758)

    great depth of field ...

  10. #10
    Drew Wiley
    Join Date
    Sep 2008
    Location
    SF Bay area, CA
    Posts
    10,591

    Re: Dynamic Range of Portra and Ektar (for the Sekonic L758)

    Yes, that's correct. I always carry an 81A for overcast sky or mildly bluish shadow correction, and light pink sky filter (2A etc) for high-altitude UV issues or minor tweaking, and an 81C for deep blue shadows under open blue skies. Split lighting (some of the scene under deep shade, some under open direct sun) presents
    a trickier problem requiring Zone III preflashing thru a warming filter. Ektar doesn't artificially warm the shadows like Ektar. This means it is capable of cleaner
    natural hues overall (nice for landscape work), but will give cold shadows where they are truly cold. The other direction, skies can go cyan if not properly exposed. Controlling all this is no harder than what Hollywood photographers have done with neg films all along, or what chrome shooters routinely did whenever they wanted more realistic results. Otherwise, if this is an annoyance, just shoot Portra 400. It's a lot more forgiving but will yield a bit more of a classic color neg look. Portra 160 even more. Ektar is what you reach for when you want a color neg film that behaves more like a chrome in terms of contrast and clean saturation.

Similar Threads

  1. Dynamic range of (new) Ektar 100
    By Lachlan 717 in forum Darkroom: Film, Processing & Printing
    Replies: 4
    Last Post: 18-Nov-2010, 14:15
  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
  •