I surrender and have to admit the error of my faulty memory. In doing
my own investigation I have discovered essentially the same as you've
described here. Also the additional piece of information that older
measurements of film's dynamic range didn't count what can now be
extracted with good scanning technique... as you yourself have
described. I looked for specific claims on Kodak's website but didn't
find anything except a comment by a film maker that Kodak's latest movie
films give him 14 stops. But I also saw some of the claims of up to 19
stops and not that this was bundled with a comment about extensive
scanning work to extract what's there.
I also had to review DPReview's measurements of dynamic range in their
various test and discovered that the full-frame Canons and Nikons of the
last few years (but not the very latest) test at 8.4-9.2. The big
surprise was the OM-D E-M5 which (from reading the graph) appears to be
in the lead at about 9.5.
Chuck Norcutt
On 5/2/2012 11:27 AM, Ken Norton wrote:
>> You are quoting DR numbers for film higher than anything I have ever
>> seen. What I'm interested in is not the AG dynamic range but what Kodak
>> or Fuji says about their films.
>>
>> Numbers I'm familiar with are more like 5-6 stops for slide film and
>> 9-11 stops for negatives. Do you have some non-AG numbers to dispute that?
>
>
> Maybe tonight I will be able to pull up my test scans of Ektar 100.
> I'm gone 4-5 days a week and don't always have the appropriate
> computer with me that has the files. And when I do have that computer,
> my schedule does not always allow me to do these kinds of things.
>
> As to my wild claims about film, it is almost universally agreed that
> Ektar has between 12-14 stops. What is funny is that the latest
> variations of Portra far exceed that, but I personally haven't tested
> the range, just enjoyed it. There are claims that the newest Portras
> (160NC and 400) can capture anywhere from 16-19 stops depending on who
> is doing the claiming. I cannot substantiate those claims, but don't
> doubt them either. These films are in a world of their own. I recently
> shot a project using Portra 400, which unfortunately I am forbidden to
> share the images due to the client's trade secret issues, (I don't
> even have the negs or files anymore as they were turned over entirely
> to the client), but the range of detail at all brightness levels is
> staggering. My understanding is that this film has no less than nine
> layers--three of each color.
>
> I'll have to word picture here, but in one photograph, the device
> reflected my studio lights. I wanted to see how much highlight detail
> was there, so I did a custom scan and proceeded to pull the exposure
> and pull the exposure and pull the exposure. The end result was that I
> could actually see the nylon fabric pattern of my softbox. Yes, this
> also required a pretty good lens. :) But I estimate that I pulled the
> exposure of the scan/digital file back 8 stops and this was still
> right up there near the top.
>
> One thing that Kodak has done an excellent job of with the latest
> formulations is that the film sharpness holds much better now in the
> shadows. In the past, it would get muddy in the shadows, but 160N and
> 400 are both exceptional at holding shadow detail sharpness. Ektar
> still gets muddy. (muddy is relative, one person's mud is another
> person's concrete mix).
>
> As to the claims that slide film only had 5-6 stops--that's pretty
> much false. Even Velvia does a couple more than that. But if you
> consider doing analog prints using "Cibachrome" printing and no
> masking, yes, it's true But masking was a way for darkroom techs to
> recover the hidden two stops that are there but more difficult to
> extract. With a decent scanner that has excellent DMAX capabilities
> (Like the Nikon V-ED or 5000), that's a non-issue and a skilled
> operator will pull quite a bit more out than what the auto mode and a
> flatbed scanner will do.
>
> It is true that the dynamic range (or latitude or whatever else you
> want to call it) of the latest negative films is staggering. To enjoy
> this, you must have a good scanner and good technique. Otherwise, the
> gains are marginal over the best of digital.
>
> DXO did a little brief comparative between the Nikon D800 and I think
> Portra 160NC. The film blew the D800 out of the water when it came to
> the ultimate range. However, not content to let the old technology
> win, they arbitrarily redefined the test to level the playing field by
> messing around with the SNR floor. But then, if you applied their
> other redefinition of ISO's, that ISO 160 film would be something like
> ISO 40960. DXO likes to come up with their own definitions of
> standards...
>
> AG
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