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Is it possible to get wide gamut color out of Scanstation scans (color primaries wider than sRGB/REC709 locations)??


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On the face of it the question may seem absurd, since with film having a larger gamut than sRGB/REC709 and with stills film scanners all handling wide gamut color scans for ages, I'd think a mega expensive pro motion picture film scanner would certainly be able to output in wide gamut color but so far, as best as I can tell, each little sample I have received seems to be locked into sRGB/REC709 primary locations. It doesn't seem to matter whether Print or PrintLog option was used or whether it is DPX16, DPX10, DNG or ProRes4444.

If I look at the DNG output in an exif viewer and look at the Forward Matrix it seems be one incredibly close to sRGB/REC709 primary locations (perhaps just slightly twisted since it seems to be in reference to D50 values instead of D65). If I force programs to assign color primary locations of sRGB/REC709, all files seem to look about the same as just letting programs load them as default. Also I see that the DNG file has the ColorimetricReference tag set to display referred (like a JPG) rather than scene referred (like most true RAW files would).

If I have a display set to REC709 and assign the file to be interpreted as if it is REC709 it looks pretty normal and not all washed out and slightly twisted in color if it was stored in reference to wide gamut color primary locations. Like if you take a ProPhotoRGB image and do that it looks horribly dull. And if switch the display to native wide gamut and view one of the samples assigned to be interpreted as REC709 it look radioactive instead of at least somewhat normal. If I try to load a DPX16 frame into Photoshop it says no color profile found for file, if I assign it to be sRGB it looks pretty normal and about how it looks loaded into Resolve or PremierePro.

Now sure the files are stored in more than 8bits per channel and some samples were log like DPX10LOG and so the gradations are finer than 8bit SDR REC709 and the tonal curve may be way different for like the DPX10LOG files and such, but the color primary locations just seem awfully like they are sRGB/REC709.

One odd side note is that Adobe ACR loads the DNG output looking about 1500K color temp different than Resolve does (interestingly the AsShotXY is D50 as is the shot light source and sRGB/REC709 are based on D65, so 1500K apart so it seems some programs are maybe accounting for that and some not, with the files being listed as display referred, maybe Adobe is technically correct in that it treats them only as pseudo-RAW and doesn't adjust any color temp stuff at all and just loads everything exactly as is once the ForwardMatrix and AnalogBalance matrices are applied, although I suspect the 1500K different look of the ProRes samples and how they load into Resolve or the DPX16 loads into PremierePro or the DPX10Log loads into PremierePro with the LUT applied).

So for all these reasons I feel like the scanner seems to be most likely only giving sRGB/REC709 standard gamut locked color primary referenced output and clipping what the film is capable of (in some frames you even see the gamut plot just straight line up against the edge of sRGB/REC709 gamut which means the original film surely extended past that gamut).

Does anyone have any idea what could be going on? Is there some special setting that the scanner is missing setting in order to get native gamut output from the scanner? Again I am not talking about bit depth or fineness of gradations or LOG vs this or that or anything to do with tonal curve I am talking about color palette, where the locations of the three primaries are set. Now maybe the film is way more saturated than I think and it really is somewhat wide gamut, maybe a little shy of P3 or something but still looks kinda normal treated as sRGB/REC709 color primaries, but then how come the ForwardMatrix in the DNG basically appears to reference sRGB gamut? And if it is some custom semi-wide gamut, then how come some of the files have no reference as to where the primaries should be? How could anything know what the DPX16 data or what not is supposed to be in reference to? Maybe they just default to guessing REC709 if nothing else is there to go by but then how does the user know what to do with the files? And how come the cubeLUT the scanner spit out for the DPX10LOG seems to give the same color look as REC709 primaries?

Thanks.

 

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19 hours ago, Robert Houllahan said:

What Scan Station? Was it in 2-flash? 5K machine or 6.5K machine?

I do find the scans from our Scan Station to be allot crunchier than the Xena scans or the Arriscan.

The Scan Station is very fast.

Thanks. They were 5k mini test scans from the 6.5K machine under 2 flash.

It's not the tonal curves or crunchiness or whether shadows are all there or highlight captured well or there is lots of fine micro-tones and such that are under question in my case. I'm simply wondering about the color gamut, as in the location of the three color primaries that the data is stored in reference to in the files. As in can it capture the intensely saturated cyans, yellows, redorange etc. that film can that is beyond what sRGB/REC709 gamut can handle or is the scanner simply, as hard to believe as it would seem, actually locked into some old school broadcast restricted color palette that is smaller than what film or say P3 can handle. My question is not regarding the usual talk about whether shadows have detail or highlights are blown are nicely separated or bit depth, etc. The samples looked fine enough other than for they seemed to have the color palette clipped to sRGB/REC709 as really intense cyan and red-orange in some frames which just straight line clipped along sRGB/REC709, the film itself clearly had had richer colors than the small, standard sRGB/REC709 gamut could hold (again nothing to do with HDR or shadows or highlights or noise or anything like that, talking color palette primary locations) and more than that what metadata was in some of the files seemed to be sRGB color palette metadata (not necessarily for the tone response curve and certainly not REC709's 8bits, just talking the location of the color primaries).

 

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1 hour ago, David Mullen ASC said:

You would think a lot of fine micro-tones in color would not fall far out from Rec.709... that sounds more like a resolution and bit depth issue.

Thanks.


But actually that is not what I am talking about, sorry for any misunderstanding. I'm NOT talking about the tonal response curve or bit depth or banding/posterization or getting subtle micro-tones of color differentiation or any of the things I see talked about most often.

I am talking simply about what color primaries the data are stored in reference to and surprised that so far there seems to be no way for the scanner to find a way to get wide gamut color data out of the scanner. Everything seems to have colors within REC709. Everything about the files implies they are locked into a small sRGB/REC709 gamut rather than something large enough to hold all the colors that motion picture film can potentially show. And I even see like in one scene with a big orange-red orb how on a gamut plot it's all straight line hard edge against border of the G/R line of sRGB/REC709 (and the file itself has the interpretation matrix that of sRGB/REC709 colors instead of something wide like native gamut of the scanner or something or even P3).

I'm not having a problem with getting subtle shade differences or color differences, I'm having trouble getting files that contain colors referenced to a gamut wide enough to properly contain motion picture film's full palette. It all seems to be stored in reference to the old broadcast video standard palette and thus can't show any colors beyond that at all.

 

 

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39 minutes ago, Tyler Purcell said:

Why would you think it's a Rec 709 color space? What makes you assume that? 

Well as I said:

If I look at the DNGs the samples all have in the metadata a ForwardMatrix1 that is very close to the standard sRGB/REC709 color primary standard forward matrix, just a tiny bit different (and that might be just down to a D50 vs D65 white point).

And if change the entries in the ForwardMatrix1 in the file and then reload it then Adobe programs and Resolve both load them with crazy colors so that matrix IS being used by those programs to interpret the color primaries otherwise messing around and putting weird values into it wouldn't make any difference.

 The matrix the files came with is very far from a really wide gamut matrix like ProPhotoRGB would have and far off from even what a P3 matrix would be like.

Also if I go into any RAW converter program and simply assign the DNGs  a colorspace of sRGB then the colors look just the same as the DNGs do loaded into Adobe or Resolve (minus perhaps a D50 to D65 shift).

If I load say one of the DPX16 files into Photoshop it complains that there is no colorspace associated with the file, if I tell it to assign sRGB then it loads into Photoshop looking pretty much how it loads into Resolve or Premiere Pro and looks pretty much like the DNGs did loaded into Adobe ACR (minus the 1500K difference here) or Resolve and looks pretty similar to the ProRes4444 output from the scanner and pretty similar to how the DPX10LOG looks loaded into PremierePro with the cube LUT the scanner made for it. If I tell it to assign P3 then it looks different and if I tell it to assign REC2020 or ProPhotoRGB then it looks way different and very strange.

If I have my display set to REC709 and assign a profile of sRGB to the DNG and view it in an image viewer the image looks pretty normal and pretty close to how it loads into Resolve. If I do the same with an image that I know is actually say stored in reference to say ProPhotoRGB wide gamut primary locations then it looks way dull and tinted.

If I change my display to native wide gamut color mode and assign a profile of ProPhotoRGB to the DNG and view it it looks radioactive. If I do the same for any sRGB JPH I have the same it then looks radioactive. OTOH if I do the same to a photo I know is in some wide gamut format it looks reasonably normal (a little hot if it is in say P3 which is still a fair bit smaller than PropPhotoRGB).

Maybe I am somehow mixing something up, but I can't think what. If the files are not locked into a restricted sRGB/REC709 color gamut then how come the DNG have a more or less sRGB color gamut matrix associated with them for color interpretation and how come if I simply assing them an sRGB/REC709 color gamut the files act nearly the same and how come if I assing that to DPX and load into Photoshop it then shows the same colors as they do loading into Resolve or Premiere Pro?

I could understand if the ForwardMatrix was just nonsense meant to be ignore for these DNGs or associated just with an embedded JPG preview but exiftool says the DNGs from the scanner have no embedded JPG preview and if I change the entries in the matrix then Adobe ACR and Resolve load the images all messed up with crazy colors.

 

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37 minutes ago, Tyler Purcell said:

Why would you think it's a Rec 709 color space? What makes you assume that? 

images that I know to be in sRGB/REC709 seem to behave (color gamut-wise, again NOT talking about bit depth or fine gradations or LOG tonal curves and whatnot) just like all the sample outputs from the Scanstation that I got. And they don't appear to behave at all like any images that I know to be in wide gamut format (like from my DSLR or stills scanner when used to output in some wide gamut format).

 

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Is there some setting somewhere on the Scanstation 6.5K that sets either native scanner color gamut vs. old broadcast standard REC709 color gamut that maybe the scan operator can't seem to find, that is maybe labelled in some weird, confusing way that makes it hard to find?

 

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Does anyone here think they have any DPX16 or DNG files from a Scanstation 6.5K stored in reference to some wide gamut format (like P3 or REC2020 or more likely native scanner gamut primary locations)? And again, I am NOT referring to the tonal curve of REC2020 or bit depth or LOG or flat or whatnot, simply about the location of the color primaries and whether the color gamut is wide or standard broadcast. Like how the new UHD format blu-rays not just have more bits per channel and have HDR but also store colors in reference to the very wide color gamut of REC2020 even if mostly restricted to the P3 color gamut within that which is still a good deal wider than the old REC709 color gamut of blu-ray and HD broadcast TV. Like how you can look at intensely colored fall foliage and flowers and sunsets and tropical waters and see much more intense colors if you view pics taken with a DSLR and the images processed in a wide gamut color format and then view them on a monitor set to wide gamut format (even if it is still in SDR mode).

Oh, also the metadata in the DNG samples I received has the ColorimetricReference tag set to 1 which means display referred and not scene referred. This triggers Adobe ACR to load the DNGs RAWs as pseudo-RAWs and changes the color temp slider from Kelvin scale to a points scale instead like if you force jpgs to be loaded into Adobe ACR. Which also seems strange. I downloaded some video shot on someone's drone and output as DNG and it had that set to 0 and the same for shooting MLR on a DSLR and then AdobeACR loads them as true RAW and gives you the normal Kelvin slider for color temp.

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I'm confused. How are you testing the output gamut of a file without knowing the input value? Are you just testing on white light? Any tool showing you gamut, would show you "actual" image gamut, which is always compressed coming from the scanner anyway. 

You can't convert a gamut from one type to another, that doesn't ever work. 

Theoretically you'd "add back" the missing gamut information in post when you work in an expanded range. 

Where I understand your reservations about this process compared to shooting on a DSLR in RAW, those imagers and imaging systems are very different than a film scanning system. You run out of dynamic range super fast on a DSLR. Film has WAY more dynamic range. So to compensate for this, we compress the film information and then expand it in post. So it shouldn't matter what the compressed gamut is on the DPX files. Once expanded it should fill in the missing data. 

 

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I am not able to scan to DNG direct with our Scan Station but maybe that is in a later software release.

I generally think the 2-flash is 14bit precision as the Sony Pregius 6.5K sensor is 12bit.

I do not know exactly what Lasergraphics is doing under the hood on the Scan Station but on the Xena scanner there is a Bayer mask transformation matrix to overcome some of the (quite large amount) of color channel cross talk. It is possible that the Scan Station uses a similar matrix or a 3D Lut to manage this aspect of using a Bayer mask sensor and the color dyes Sony used on the silicon.

I could do a comparative test on our Arriscan in 2-Flash which is 16 bit and true RGB.

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6 hours ago, Tyler Purcell said:

I'm confused. How are you testing the output gamut of a file without knowing the input value? Are you just testing on white light? Any tool showing you gamut, would show you "actual" image gamut, which is always compressed coming from the scanner anyway. 

In an image file based upon the normally used tristimulus model, the data has to be stored with in reference to some primary color locations otherwise how in the world do you even know how to interpret the data? You need to know where on the CIE XY chart the R, G and B color primaries are located.

The DNG output file has a ForwardMatrix in the metadata that tells programs how to interpret the data. Color management modules are standardized work in CIE D50 XY and that ForwardMatrix is multiplied by the R,G,B color value to convert it from whatever reference it is in to D50 CIE XY. The matrix in the sample files I received is extremely close to the matrix one would use to convert from data stored in reference to the sRGB/REC709 color gamut (the slight difference might be because the scanner light source was called D50 and sRGB/REC709 use a D65 white point).

And then again, if I load in a DPX16 and tell a program to assume that the data should be interpreted as if was stored in reference to sRGB/REC709 primary locations, it ends up looking pretty much the same as the file loads into PremierePro or Resolve or what the REC709 ProRes output looks like.

 

 

6 hours ago, Tyler Purcell said:

You can't convert a gamut from one type to another, that doesn't ever work. 

It's done all the time. If you have an image in say AdobeRGB and are viewing on a screen set to sRGB any color managed viewer will conver the gamut from AdobeRGB to sRGB so it looks normal on that screen.

 

6 hours ago, Tyler Purcell said:

Theoretically you'd "add back" the missing gamut information in post when you work in an expanded range. 

You can't add back colors that were clipped to begin with. If the data was clipped away, it is clipped away. You can boost some saturation and saturation at bright levels and sort bring some back to an extent, but it won't be the same and it's hard to not get other stuff artifically boosted looking. Also the tints might go all wrong since the color primary location it was interpreted as might not be on a straight line out in saturation from th white point but might be shifted one way or another.

 

6 hours ago, Tyler Purcell said:

Where I understand your reservations about this process compared to shooting on a DSLR in RAW, those imagers and imaging systems are very different than a film scanning system. You run out of dynamic range super fast on a DSLR. Film has WAY more dynamic range. So to compensate for this, we compress the film information and then expand it in post. So it shouldn't matter what the compressed gamut is on the DPX files. Once expanded it should fill in the missing data. 

 

I'm not talking about dynamic range though. Dynamic range and color gamut are not the same thing (although more dynamic range can make the gamut larger in a way, but that is not the part I am talking about). I'm not talking about like SDR vs. HDR. I'm talking more along the lines of color gamut portion of say sRGB vs AdobeRGB vs P3 vs REC2020 etc.

 

I'm talking about stuff like:

https://www.eizo.com/library/basics/lcd_monitor_color_gamut/

https://webkit.org/blog-files/color-gamut/

https://nick-shaw.github.io/cinematiccolor/common-rgb-color-spaces.html

https://www.benq.com/en-us/business/resource/trends/understanding-color-gamut.html

https://www.displaymate.com/Display_Color_Gamuts_1.htm

 

and I'm not talking about stuff like being able to see details inside of a room as well as stuff out the window in bright sun at the same time and I'm not talking about whether you have large steps between each tone or super fine gradations, etc.

 

Camera RAW files tend to not include the color primary locations since the manufacturers get all secretive, but that also is why you keep needing RAW processing updates when a new camera comes out. The software company has to go measure the color filters and sensor and see what the camera captures in terms of where the color primaries should be located and then it knows what the values in the RAW file mean. If we are say 8bit just make it simple, what does say an R,G,B of 255,200,10 even mean? if you don't know where the R, G and B color primaries are you have no clue what 255/255 red and 200/200 green and 10/255 blue means. If the green is located where it is in sRGB/REC709 it means one thing, if it is way, way up there on the CIE XYZ/xxY chartthen it means something else. If the data was in reference to the former but you treated it like it was in reference to the latter then you'd get absolutely nuclear intense looking greens and they wouldn't just have the green component way oversaturated it would also be shifted in tint most likely as well and have too much of a blue or red tint to it as well. That is the sort of thing I am trying to get at.

 

 

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4 hours ago, Robert Houllahan said:

I am not able to scan to DNG direct with our Scan Station but maybe that is in a later software release.

I generally think the 2-flash is 14bit precision as the Sony Pregius 6.5K sensor is 12bit.

I do not know exactly what Lasergraphics is doing under the hood on the Scan Station but on the Xena scanner there is a Bayer mask transformation matrix to overcome some of the (quite large amount) of color channel cross talk. It is possible that the Scan Station uses a similar matrix or a 3D Lut to manage this aspect of using a Bayer mask sensor and the color dyes Sony used on the silicon.

I could do a comparative test on our Arriscan in 2-Flash which is 16 bit and true RGB.

Thanks.

Yeah, the Scanstation 6.5K also has a Bayer sensor like most DSLR so it also has to debayer the file (or in the case of DNG output let the software the user uses do the de-Bayer). From what I read, the Director and Scanity are true RGB per pixel, etc.

The real issue is whether the Scanstation is taking the native color data and transforming it from the native color gamut of the scanner, which is surely pretty wide, and converting it to a small sRGB/REC709 primary locations (long time broadcast standard, but far less than film's color palette and far less than the new broadcast and home video standards) before writing out the data to files. It would seem shocking for them to do that, baffling, but it seems like the samples I have received have had that done to them. I'm not sure if maybe the person doing the scan had some setting somewhere set that is forcing that or if the Scanstation 6.5K simply is really being restricted to that the smaller color gamut or if I'm somehow misinterpreting the files (but then how come the DNG have an sRGB forwarmatrix and so on?).

How are Hollywood studios preserving the full color gamut of 35mm/70mm films they can in and release on UHD if the scanners are clipping stuff to a small gamut on output? Yeah they can still get true HDR out of them, but what about the colors? I know for Wizard of Oz they simply did like a B&W for each of the three Technicolor strips and they probably measured the spectral response for what each strip recorded and then custom ended up capturing the full, rich, huge color palette of three-strip Technicolor. But what about regular films like on single strip full color Eastman or Fuji or whatnot?

If you look at people doing scanning of stills from stills film cameras, you see all sorts of talk about scanning into wide gamut formats and how one should not use sRGB/REC709 if you care about preserving all the possible colors in your slide or negative.

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19 hours ago, Tyler Purcell said:

Why would you think it's a Rec 709 color space? What makes you assume that? 

Also I should clarify, I don't think it is that all the output samples are in REC709 color SPACE, they just all seem to be in REC709 color GAMUT (solely with regard to the xy locations of the color primaries on an CIE xyY gamut plot).

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I would just say that high end “finishing” scans from a Scannity / Arriscan / Director / Xena are actual RGB scans either with a Tri- Linear RGB sensor or a Monochrome Area sensor and pulsed RGB LED lamp. 

Scanners with Bayer mask sensors are fast and can make very good scans but as far as I know they are “dailes” or “archival” use machines for more critical film and tv work.

There is some tradeoff with a color sensor, the dyes used in the silicon mask are not perfect and there is crosstalk between color channels. Any scanner maker has to do some math to figure out how to deal with this.

Color sensors are capable of wide gamut and it may just be a choice engineers made building the Scan Station and a possible feature request to LG as how this in interpolated is just how the software works.

Have you asked LaserGraphics? 

 

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16 hours ago, Robert Houllahan said:

I am not able to scan to DNG direct with our Scan Station but maybe that is in a later software release.

I generally think the 2-flash is 14bit precision as the Sony Pregius 6.5K sensor is 12bit.

I do not know exactly what Lasergraphics is doing under the hood on the Scan Station but on the Xena scanner there is a Bayer mask transformation matrix to overcome some of the (quite large amount) of color channel cross talk. It is possible that the Scan Station uses a similar matrix or a 3D Lut to manage this aspect of using a Bayer mask sensor and the color dyes Sony used on the silicon.

I could do a comparative test on our Arriscan in 2-Flash which is 16 bit and true RGB.

 

I've told you and Perry time and again. All scanning options should be tested with comparison samples posted online. 

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12 hours ago, Larry Baum said:

Also I should clarify, I don't think it is that all the output samples are in REC709 color SPACE, they just all seem to be in REC709 color GAMUT (solely with regard to the xy locations of the color primaries on an CIE xyY gamut plot).

 

Where are samples of these scans...to see? 

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5 hours ago, Daniel D. Teoli Jr. said:

 

I've told you and Perry time and again. All scanning options should be tested with comparison samples posted online. 

I have no recollection of being told this.

Nice in theory but really a moot venture as high end clients already know what they want and can afford to do finishing on our Arriscan for example.

Too many variables in any scanner "shootout" and allot of the business of owning these scanners is knowing what is the right machine for the job and client budget.

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19 hours ago, Larry Baum said:

Also I should clarify, I don't think it is that all the output samples are in REC709 color SPACE, they just all seem to be in REC709 color GAMUT (solely with regard to the xy locations of the color primaries on an CIE xyY gamut plot).

Again did you have a LAD (Lab Aim Density) or TAF (Telecine Alignment Film) or some other SMPTE control film scanned to reach this conclusion?

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5 hours ago, Robert Houllahan said:

Again did you have a LAD (Lab Aim Density) or TAF (Telecine Alignment Film) or some other SMPTE control film scanned to reach this conclusion?

 

It wasn't a TAF. The little sample bit I got back didn't include any of the color or gamma tracking frames at the very start of the print, just a few seconds of the film itself. A TAF doesn't seem to have very saturated colors so not sure you could see much from that. Perhaps if it had one of the fuller color checker type charts, as some prints do, can't recall exactly what this one has on it at the start, some of the colors would be beyond sRGB/REC709 primary locations. It would be good to get those frames included in the full final scan to see what tweaks need to be made to scans from the machine to get them closer to perfectly matching the print, but that seems like a separate issue.

I'm not sure why a TAF scan would tell you any more about the color gamut than just scanning a few seconds of a final print and seeing what the metadata in the DNG output says or seeing how the DPX react assigned different gamut profiles. Maybe one of the more comprehensive patterns would have a few patches out of REC709 gamut and one could try to see if they looked a touch muted relative to the others or see if any program or any profile assignment could bring them back, but that is a bit subtle.

You can easily tell roughly what sort of gamut any jpg image was stored in reference to so long as it has any reasonable amount of color in the scene, apply the wrong assignment of gamut and it will look normal or way oversaturated and twisted or way undersaturated and twisted (and for that file type the metadata would tell you the reference color gamut as well even if the image which 100% white or pitch black).

 

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22 hours ago, Robert Houllahan said:

I would just say that high end “finishing” scans from a Scannity / Arriscan / Director / Xena are actual RGB scans either with a Tri- Linear RGB sensor or a Monochrome Area sensor and pulsed RGB LED lamp. 

Scanners with Bayer mask sensors are fast and can make very good scans but as far as I know they are “dailes” or “archival” use machines for more critical film and tv work.

There is some tradeoff with a color sensor, the dyes used in the silicon mask are not perfect and there is crosstalk between color channels. Any scanner maker has to do some math to figure out how to deal with this.

Color sensors are capable of wide gamut and it may just be a choice engineers made building the Scan Station and a possible feature request to LG as how this in interpolated is just how the software works.

Have you asked LaserGraphics? 

 

I suppose for some reason Lasergraphics might have limited native scanner primary reference wide gamut scans to the Director, but that would seem surprising. Even cheap stills film scanners, even some with Bayer method, allow for wide gamut scans and even full color scanners like Nikon 9000 Coolscan cost like 20x-100x less and came out years earlier and allow wide gamut film scans. So I wonder if maybe there is some weirdly name option that the scanner isn't seeing and has it set to REC709 color gamut when maybe some little setting change could allow for wide gamut. I mean maybe there is something about the scan files I am simply not interpreting correctly, but so far I can't see anything I am doing wrong in that regard, but open to suggestions.

Yeah Bayer sensors are not perfect, but almost all DSLR use them and virtually all DSLR have put out wide gamut RAW files or JPGs from day 1. You lose a bit of color resolution and precision and get more metamerism and so on and so forth, but in terms of primary locations, most of them have them set quite wide indeed, way beyond sRGB/REC709.

I did just ask Lasergraphics the other day whether the 6.5K machine can output data referenced to color primaries wide gamut than those of sRGB. I will see what they have to say, if anything. I've heard rumors that unless you own a machine or appear ready to buy one that they might not talk much, if at all, so I'm not 100% sure I will even get a response.

Someone else using one of the machines asked them a few questions somewhat along these lines and said they got a kinda vague answer that didn't really answer anything and it was sort of an "it's all proprietary secrets" kinda response that didn't make anything clear. I'll see if they get a more clarifying answer to a couple more exactingly specific questions.

In the meantime I was sort of hoping that in one of these forums someone would just be like oh yeah you just have to make sure that so and so setting is set/not set and then you'll get wide gamut reference output. Or, although it would be a shame, a nope, that one limits it with reference to REC709 color primary locations there is nothing the scanner could have done using this machine but so and so brand and model can do that. It's almost impossible to find info on exactly what any of the models from any maker can do regarding color gamut. I found a few vague hints that maybe the Cintels can actually give wide gamut color, but it is not entirely clear (they also seem inferior otherwise to stuff like Scanstation, etc.). It's surprising since in the film stills world it's trivial to find this info for any stills film scanner and people are talking all over about standard and wide gamut scans. But the motion picture world is a much smaller world. I do see that sort of talk a lot in purely digital work flows, but haven't had luck finding a lot when it comes to motion picture film scanned sources, only for digitally shot productions where, in recent times, you can find a lot of talk about wide gamuts and such (or back in the day, when the first digital motion picture cameras appeared when you'd hear some bash them for having small REC709 palettes and poor DR and lacking in the DR of film and it's more rich color possibilities).

 

 

 

Edited by Larry Baum
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Were the scans DNG from negative or print?

I think the DNG files bypass all the color pipeline in the scanner, but I am not sure.

The Scan Station does a base cal which pulses the R,G,B leds individually and then together to find clipping for each channel to set color balance and lamp intensity to the film stock in the scanner.

So I am not sure what kind of color science pipeline stuff happens for DNG after that.

The Sony Pregius IMX 342 is the sensor used, here is one Machine vision manufacturer's sheet which has spectral response stuff on it:

https://www.imperx.com/cmos-cameras/C6440/

Edited by Robert Houllahan
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I've noticed that some in the stills world can concentrate on technical aspects of image that in the cine world could be considered overly fine and rarefied details of image science that few have the luxury to contemplate or study in-depth. After all, the individual pictures flick by at the rate of 24 or more per second. There's much to be done and considered and only so much time to give to the niceties of the single image. I'd say in motion pictures we tend to go with what 'just looks good' and if that means a simple colour science and a simple means of acquiring the end result then that's the way it just is. If I'm way out of line that's fine, just tell me. But I was struck with this thought while reading this thread.

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