How is Portra "optimised for scanning"

Discussion in 'Color: Film, Paper, and Chemistry' started by tomfrh, Dec 18, 2017.

  1. Ian Grant

    Ian Grant Subscriber
    Ads Enabled

    Messages:
    20,057
    Joined:
    Aug 2, 2004
    Location:
    West Midland
    Shooter:
    Multi Format
    Kodak had issues with surface artefacts also known as micro reticulation, this became an issue when digital negative scanners were used for minilabs, it was the gelatin supercoat rather than the emulsion itself. It was causing interference patters due to scanner resolutions and appeared as excessive graininess, you could print OK optically. Kodak resolved this to a large extent with improved hardeners a number of years ago.

    However in more recent years they've made even greater improvements making their films far better for scanning. In simple terms the Gelatin super coat is now much flatter, no longer has a matt look. Kodak make similar statements about improved optimisation for the newer versions of other films (Tmax etc).

    Wet mounting for scanning or optical printing was one way to overcome these problems, a technique that goes back to the mid 1920's but of course it's not practical in commercial d&p labs/minilabs.

    Ian
     
  2. Chris Livsey

    Chris Livsey Member

    Messages:
    646
    Joined:
    Aug 10, 2008
    Shooter:
    Medium Format
    A discussion on the Vision3 film in another thread is related as Portra shares Vision3 technology and in a little digging I found this:

    https://www.kodak.com/uploadedFiles/Motion/Products/Camera_Films/5203/Resources/5203_ti2657.pdf
    The section on Post Production Scanning links, with a little more digging, to this one
    https://www.yumpu.com/en/document/v...ommendations-for-extended-dynamic-range-kodak

    Which rather changes the OP question about how Portra is optimised for scanning to how should we optimise scanning for Portra!!
     
  3. Poisson Du Jour

    Poisson Du Jour Member
    Ads Enabled

    Messages:
    5,407
    Joined:
    Jul 1, 2008
    Location:
    Geelong/Richmond VIC
    Shooter:
    Multi Format
    Groups:
    There are definitely commercial labs that carry out wet-scanning. At least on this side of the world!
    Some of my production work is produced through wet-scanning in a busy commercial lab (there are two other labs). There are a few of us doing this. True, it is a messy and smelly affair and it requires a block of booked time where no other work is done (that is not wet-scan related). Minilabs? Do they still exist??
     
  4. Ted Baker

    Ted Baker Member
    Ads Enabled

    Messages:
    203
    Joined:
    Sep 18, 2017
    Location:
    London
    Shooter:
    Medium Format
    I guessed as much earlier on :smile:
    A typical 16bit film scanner should cope with this improved range easily, where as the DPX scanner format is/was optimised for a particular generation of cinefilm, to make the best use of the available storage space. (10bits per channel)
     
    Last edited: Dec 20, 2017
  5. Chris Livsey

    Chris Livsey Member

    Messages:
    646
    Joined:
    Aug 10, 2008
    Shooter:
    Medium Format
    But are they 16 bit really? Medium format backs were said to be 16 bit, which they were but it was 14 bits padded out, modern Sony cameras for example go down to 12 bit when anything "pushy" is required, just wondering :angel:
     
  6. Ted Baker

    Ted Baker Member
    Ads Enabled

    Messages:
    203
    Joined:
    Sep 18, 2017
    Location:
    London
    Shooter:
    Medium Format
    That's possible, in any case if they can give good results with a transparency then they should have enough room for these newer negative films
     
  7. Lachlan Young

    Lachlan Young Member
    Ads Enabled

    Messages:
    1,577
    Joined:
    Dec 2, 2005
    Location:
    Glasgow
    Shooter:
    Multi Format
    I understand it can also have a lot to do with the nature of the analogue to digital converter - and if it's linear or logarithmic. For example, apparently the 12-bit log ADC's in Heidelberg drum scanners do a better job of making a 16-bit linear file than some linear ADC's of nominally higher bit depth.
     
  8. Arbitrarium

    Arbitrarium Member
    Ads Enabled

    Messages:
    97
    Joined:
    Sep 28, 2016
    Location:
    United Kingdom
    Shooter:
    35mm
    I developed a roll of Portra 160 in the same tank as an Agfa Vista 200 yesterday. The Agfa dried curly as I was expecting but the Portra dried completely flat which really surprised me. So there's that.
     
  9. Anon Ymous

    Anon Ymous Member
    Ads Enabled

    Messages:
    2,111
    Joined:
    Feb 7, 2008
    Location:
    Greece
    Shooter:
    35mm
    Groups:
    All Kodak C41 films I've developed lately dry dead flat. Agfaphoto ones on the other hand...
     
  10. trendland

    trendland Member
    Ads Enabled

    Messages:
    2,628
    Joined:
    Mar 16, 2012
    Shooter:
    Medium Format
    I have real doubts IF in this market situation a manufacturer would improve a film emulsion to optimize scanning properties.
    We may imagine this could be cause also disadvantages in concern of analogue workflow. ( the optimized scan characteristics)
    So from my understanding you have different emulsions today - some are worst if you want to scan - others
    BRING good scan properties.
    And the Kodak Portra familie belongs to last category.
    Am I right - or am I right ? :D....

    with regards
     
  11. trendland

    trendland Member
    Ads Enabled

    Messages:
    2,628
    Joined:
    Mar 16, 2012
    Shooter:
    Medium Format
     
  12. Lachlan Young

    Lachlan Young Member
    Ads Enabled

    Messages:
    1,577
    Joined:
    Dec 2, 2005
    Location:
    Glasgow
    Shooter:
    Multi Format
    My comments were intended to point out one of the more notable differences between the Tango etc & other high end PMT or CCD scanners with a fluid mount capability. There are scanners which will outresolve a Heidelberg, but the Heidelbergs seem to have an edge in terms of what they can usefully dig out of a negative or transparency. Pretty much any high end scanning kit runs rings around your average Epson etc, and for most negative scanning purposes, pretty much all high end scanners are very good indeed - it's really a question of how much resolution you need that's the deciding factor.
     
  13. trendland

    trendland Member
    Ads Enabled

    Messages:
    2,628
    Joined:
    Mar 16, 2012
    Shooter:
    Medium Format
    I see - that should matter also.
    Yes resolution - thats the case of interest.The great point.
    Short answer : max. resolution.
    By the time - Kodak obviously had also propper scan technique in the 90th.
    The machines the used for their Kodak Photo CD.
    The proffesional Photo CD had 4000 x 6000 resolution with 135-36 films (1997!!!!!) this was the killer aplication to normal pc.

    with regards
     
  14. Sponsored Ad
  15. Ted Baker

    Ted Baker Member
    Ads Enabled

    Messages:
    203
    Joined:
    Sep 18, 2017
    Location:
    London
    Shooter:
    Medium Format
    No, :wink: the point being, that all negative film has a latitude that exceeds the capabilities of the print. In black and white you always have the easy option of dodge and burn etc. You could of course do the same with color printing but it's not as straightforward, where as scanning it is easier to make use of the extra latitude.
     
    Last edited: Jan 4, 2018
  16. Bill Burk

    Bill Burk Subscriber
    Ads Enabled

    Messages:
    6,176
    Joined:
    Feb 9, 2010
    Shooter:
    4x5 Format
    This makes sense.

    Also, to state the obvious... it's not Kodachrome (so it doesn't mess with Digital ICE like Kodachrome does).
     
  17. Sirius Glass

    Sirius Glass Subscriber
    Ads Enabled

    Messages:
    28,060
    Joined:
    Jan 18, 2007
    Location:
    Southern California
    Shooter:
    Multi Format
    Groups:

    You can put you doubts aside. Kodak made a concerted effort to improve Portra scanability.
     
  18. DREW WILEY

    DREW WILEY Member
    Ads Enabled

    Messages:
    6,333
    Joined:
    Jul 14, 2011
    Shooter:
    8x10 Format
    If it's on the film and can be recovered using a scan, it can be recovered and printed fully analog. Making and using supplementary film masks might seem like a nuisance, but so is removing scanning fluid. And either way, you've got to clean dust off first. But the real question is what will be the actual quality of those far reaches of film "latitude"?
     
  19. NJH

    NJH Member

    Messages:
    604
    Joined:
    Dec 30, 2013
    Location:
    Dorset
    Shooter:
    Multi Format
    Bit range is pretty much irrelevant to most ADC systems, the limiting factor will nearly always be your noise floor. Lots of mythology around ADC, sadly including from those in the various industries either using them or making them.
     
  20. Ted Baker

    Ted Baker Member
    Ads Enabled

    Messages:
    203
    Joined:
    Sep 18, 2017
    Location:
    London
    Shooter:
    Medium Format
    I'm sorry that's just nonsense, bit range is very relevant particularly in scanning, as the film never represents a linear measurement of the light in a scene. Consequently you need quite high precision in one part of the range and less in others.

    As a simple example 18% of the range is roughly half of the range that our eye perceives in terms of brightness.
     
    Last edited: Jan 5, 2018
  21. trendland

    trendland Member
    Ads Enabled

    Messages:
    2,628
    Joined:
    Mar 16, 2012
    Shooter:
    Medium Format
    Well - I insist on my opinion.
    It is quite clear from history also. Scanning issues wasn't issues before 1995. It was a real niche and I am sure Kodak never mind about (exeptions would have made sence for proffessional films during 1996 - 2000.)
    With 2000 the big boom from scanning began (to the same time we noticed digital cameras with pore characteristics).
    And after this time improvements made sence (caused from massive scanning trend) we may fixe the year 2005 BUT to this time Kodak was still in the midle of its big crisis.
    From were should came the money to new emulsion design for better scan characteristics.
    Remember also Kodak cut the money for film research in 2004 if I remember correct. The later improvements (after 2004) came (without exeption) from research made in the years before 2003.
    And within this period scanning of film was no issue to a manufacturer producing billions of films - (most for the target group of amateuric photograpers who need films only one time a year : during holidays).
    But Ian gave us a hint - so look above :
    Kodak reformulate the gelantine supercoat via improved hardeners.
    That should be done within the years I reffered (2000 - 2005).
    Sirius Glass - so pls. let us speak about a optimization in regard of scanning issues from Kodak.
    And not about a reformulation/improvement of the emulsion concerning the Portra family.
    (and other films )

    That's all I intended to state - because I can't imagine a manufacturer these days will spend money (with extreme costs) and this should stand also to the last 10years - because a small group of costumers had problems from scanning.
    And sure I remember Kodak spoke about improvement of Portra to have better scanning characteristics!
    But as I mentioned so many times before
    you should not believe everything to 100% companies tell you.
    Make your own thoughts about - then it often becomes much more clear.
    So the statement of Kodak is better to understand as M A R K E T I N G ...:D:D.
    And we should know : They optimized their films (via simple method with the use of improved hardeners)
    with regards

    PS : Thank you Ian Grand - by the time - for you competent factual information.
     
  22. trendland

    trendland Member
    Ads Enabled

    Messages:
    2,628
    Joined:
    Mar 16, 2012
    Shooter:
    Medium Format
    Well - Ted Baker - that should be a point,
    you mentioned, I have to think about first.:wink: so thank you therefore.

    with regards

    PS : .... Glad about to realize I am not allways right .... (hope you recognize the irony :whistling::whistling:)
     
  23. NJH

    NJH Member

    Messages:
    604
    Joined:
    Dec 30, 2013
    Location:
    Dorset
    Shooter:
    Multi Format
    People were talking about 16 bits, can you tell me what the actual sensor device ADC bit depth of these devices is, their noise floor and actual SNR at the read out (in other words the real number of useful sensor bits)? This is fundamentally not the same as the number of bits output from a system, or for that matter what is useful for doing software based signal manipulation.
     
  24. Ted Baker

    Ted Baker Member
    Ads Enabled

    Messages:
    203
    Joined:
    Sep 18, 2017
    Location:
    London
    Shooter:
    Medium Format
    On the box it says it 16, but I would not be surprised that it is just marketing and it's 14, which would be enough. But 12 bits for a linear AD would be the absolute minimum, maybe 10bit if the negative was perfect and no tonal corrections are needed. In this context a bit of noise would actually be helpful.

    It is very straight forward to test this, create a scan and save with a gamma of 1 (real gamma of 1) and 8bit, this will basically turn your scanner into a scanner with an 8bit A/D then try and make your corrections/post processing.
     
    Last edited: Jan 5, 2018
  25. Sirius Glass

    Sirius Glass Subscriber
    Ads Enabled

    Messages:
    28,060
    Joined:
    Jan 18, 2007
    Location:
    Southern California
    Shooter:
    Multi Format
    Groups:

    The last time I looked a few years ago, there were few true 16 bit per color cameras, many 14 bit and 12 bit per color cameras because there were problems building 16 bit analog to digital converts that would work in digital cameras.
     
  26. Les Sarile

    Les Sarile Member
    Ads Enabled

    Messages:
    2,047
    Joined:
    Aug 7, 2010
    Location:
    Santa Cruz, CA
    Shooter:
    35mm
    Nikon Coolscan 9000 + Nikonscan ICE has the best implementation of ICE that I have tried especially when used with Kodachrome. Below is a perfect example of how it works without introducing any strange artifacting found in others particularly Canon's FARE.

    [​IMG]
     
  1. This site uses cookies to help personalise content, tailor your experience and to keep you logged in if you register.
    By continuing to use this site, you are consenting to our use of cookies. If you have a Photrio account, please log in (and select 'stay logged in') to prevent recurrence of this notice.