Luminous Landscape Forum
Equipment & Techniques => Medium Format / Film / Digital Backs – and Large Sensor Photography => Topic started by: filmcapture on November 14, 2009, 04:00:54 pm
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I recently bought a Sinar eMotion 75LV digital back, and after finishing some shots, I encounter a problem with Brumbaer's eMotionDNG.
I simply drag the Sinar RAW file folder which contains IA, BR and WR files into the eMotionDNG window, but I find there are lots of stuck (white) pixels in the DNG files. Instead, if I go for Sinar eXposure, virtually all stuck pixels are gone. I am not sure if the Brumbaer tool is not used properly, or Sinar's eXposure has an algorithm to mask those stuck pixels though they are indeed located in the CCD sensor. Your opinions shall be appreciated.
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The Brumbaer tool relies on a sensor reference file that used to be supplied on a CD with the back. I believe Sinar now embeds this reference data within the back itself. So, the eXposure software knows where to find this information, but the Brumbaer tool does not.
Most of the features of the Brumbaer tool are now incorporated into the eXposure software. While the Brumbaer tool was a significant contribution at the time, I find that I no longer need it and now use eXposure in my workflow.
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Perhaps this thread might be of help http://luminous-landscape.com/forum/index....showtopic=39071 (http://luminous-landscape.com/forum/index.php?showtopic=39071)
Cheers,
Kumar
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Thanks, David. I used to have a Phase One P25, and I am now trying to find out if the DNG files can be processed by Capture One as well. I just downloaded a trial version of C1 5.0, it's interesting C1 can process the DNG files generated by eMotionDNG without any problem, but it has processing errors for those created by eXposure. That's why I try to stick with Brumbaer tools. I do have the original CD for my Sinar DB, I'll give it one more try if those stuck pixels could be eliminated. Anyway, the Sinar back is new to me, there should have a learning curve. Thanks again!
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Thanks, David. I used to have a Phase One P25, and I am now trying to find out if the DNG files can be processed by Capture One as well. I just downloaded a trial version of C1 5.0, it's interesting C1 can process the DNG files generated by eMotionDNG without any problem, but it has processing errors for those created by eXposure. That's why I try to stick with Brumbaer tools. I do have the original CD for my Sinar DB, I'll give it one more try if those stuck pixels could be eliminated. Anyway, the Sinar back is new to me, there should have a learning curve. Thanks again!
interesting. i never tried the brumbaer dngs with c1.
but i am afraid you will have bad luck.
brumbaer dont interpretate the ref. files with the new generation of emotion backs ( with the newer firmwares , i dont emember which was the first of such fw ), so this are dead pixels cause the ref file isnt eliminating them. might be one bit which is different, stefan stopped to update his programm and than they changed something in the ref and fw. code which made it uncompatible.
well done as many things like this, but this companies never care compatibility except with their own stuff. i never could understand such thinking, its a part of the digging of their own graves these mf companies are doing.
but, btw. try the new LR, i.m.o. its very god how adobe improves and improves their processing. alternatively RPP is very good if not the best converter available. i personally dont like C! too much, cause its always sharpening even at default "ß" settings, and this can create problems if making very big sizes upinterpolating.
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Rainer,
Two dumb questions in a row:
The original Sinar e 75LV conversion has to be done in eXposure before one goes to Lightroom, right?
What is RPP? OK, I found RPP's site, but I notice they don't support Sinar. Does this mean you convert in eXposure and then adjust in RPP?
Thanks, and thanks for all your contributions in the past.
Best,
Mitchell
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Rainer,
Two dumb questions in a row:
The original Sinar e 75LV conversion has to be done in eXposure before one goes to Lightroom, right?
Mitchell
Dear Mitchell,
Yes, Sinar's raw files have to be and are converted into DNGs only in eXposure.
Best regards,
Thierry
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Thanks Thierry,
You are so helpful as usual.
That's what I thought.
But, I guess Rainer is saying that both Lightroom 3 and RPP do a good job adjusting the DNG that comes out of eXposure?
Best,
Mitchell
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But, I guess Rainer is saying that both Lightroom 3 and RPP do a good job adjusting the DNG that comes out of eXposure?
Best,
Mitchell
That's right, Mitchell, Rainer was speaking about the produced DNGs.
Best regards,
Thierry
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Theirry,
Thanks so much.
Mitchell
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interesting. i never tried the brumbaer dngs with c1.
but i am afraid you will have bad luck.
brumbaer dont interpretate the ref. files with the new generation of emotion backs ( with the newer firmwares , i dont emember which was the first of such fw ), so this are dead pixels cause the ref file isnt eliminating them. might be one bit which is different, stefan stopped to update his programm and than they changed something in the ref and fw. code which made it uncompatible.
well done as many things like this, but this companies never care compatibility except with their own stuff. i never could understand such thinking, its a part of the digging of their own graves these mf companies are doing.
but, btw. try the new LR, i.m.o. its very god how adobe improves and improves their processing. alternatively RPP is very good if not the best converter available. i personally dont like C! too much, cause its always sharpening even at default "ß" settings, and this can create problems if making very big sizes upinterpolating.
Hi,
I wondered how RPP compares with Raw Developer. Have you done a comparison?
(By the way, I agree with you absolutely about Capture One.).
Cheers,
Jonathan
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In prefer RPP, but since the 3beta i am back with LR.
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http://www.raw-photo-processor.com/RPP/Overview.html (http://www.raw-photo-processor.com/RPP/Overview.html)
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Hi, here is my experience: I have a large magenta color stuck pixel on my emotion 75LV which only shows when I process the raw images in Brumbaer and then edit in C1 or Iridient Raw Developer (IRD). With IRD however, the hot pixel or whatever it is disappears if I shift the hot pixel threshold slider one position to the left (it's in the SharpNR menu). The hot pixel does not show if I process the DNGs generated by Brumbaer in Lightroom (2.5 or beta 3, doesn't matter); it seems that Lightroom has some way of correcting this automatically. The hot pixel also used to show in eXposure but I downloaded the latest version today and while it showed up initially in the first three or so pictures, it does not show anymore now (don't know why). Captureshop also seems to fix the problem automatically (and surprisingly, the latest version downloaded from the Sinar website is lightyears faster than the one that came on the CD with the back). To make a long story short, the only "problematic" combination seems to be Brumbaer DNGs edited in C1, as C1 does not have a way to correct hot pixels (or at least I haven't figured it out yet). Not sure if eXposure -> C1 shows the problem, haven't tried that. My workflow is Brumbaer (calibrated) -> Lightroom; I am thinking about changing to eXposure for DNG generation but eXposure still puzzles me a big way.... I hope this helps. Martin
I recently bought a Sinar eMotion 75LV digital back, and after finishing some shots, I encounter a problem with Brumbaer's eMotionDNG.
I simply drag the Sinar RAW file folder which contains IA, BR and WR files into the eMotionDNG window, but I find there are lots of stuck (white) pixels in the DNG files. Instead, if I go for Sinar eXposure, virtually all stuck pixels are gone. I am not sure if the Brumbaer tool is not used properly, or Sinar's eXposure has an algorithm to mask those stuck pixels though they are indeed located in the CCD sensor. Your opinions shall be appreciated.
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What puzzles you about eXposure? I use it every day for tethered shooting and processing finished files for clients with no need for any other work in Photoshop usually. Sinar have made it quite easy to understand in my opinion - it looks similar to most other raw processors in structure, function and gui. There is a comprehensive help and people like your dealer or the friendly LL community are there if you need specific help with something. I don't deny it does lack some of the finer features of other processors and may be a little harder to fine tune your pictures to the degree possible in LR but it is fast and stable and worth getting to know. You can always request new features from Sinar in future versions - that is the only way they will know what people want.
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My workflow is Brumbaer (calibrated) -> Lightroom; I am thinking about changing to eXposure for DNG generation but eXposure still puzzles me a big way.... I hope this helps.
In the eXposure browser window, just drag the captured files into a folder on your computer. That's it. You will then have a folder of DNG files on your computer that can be processed by Lightroom if you wish. eXposure also includes more metadata in the generated DNG files than Brumbaer (e.g., lens aperture), which may be useful for digital asset management of your images.
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What puzzles me about eXposure? Well, not the basic functionality but the seeming absence of logic in some operations. An example: I take an exposure under tungsten light - I set the WB on the back to the "Tungsten" setting, I set the input profile in eXposure to the eMotion 75 Tungsten 2009 profile, and I also choose Tungsten as the WB setting in the eXposure processing pane. Why on earth is the image still yellow/orange? Why does the Kelvin reading stay at 5500 when I set WB in the eXposure processing pane to Tungsten? Makes no sense to me (of course I can move the slider to 2850 but by that time my confidence in the software or my ability to use it starts to evaporate. Another issue: why do the previews show severe moire (magenta/cyan edges) where there is none after I enlarge the image with the loupe tool?
I had other issues with the version of eXposure that came on the CD with the back - all images imported with a severe dark green cast, calibration was entirely counter-intuitive (still don't know if the software was applying my calibration settings only to one image or all subsequent images, unfortunately the 6 page parody of a "manual" that came with the software did not help); when I tried to shoot the calibration target the software sometimes refused to acknowledge that I shot an image (in the calibration window, after it prompted me to take a shot of the target, it did not react when I shot the image).
After I read your positive comments on eXposure here yesterday I downloaded the newest version from Sinar's website and actually managed to do some good conversions but still with the white balance issues outlined above (had to fix WB manually with the color picker tool, after that the resulting image was as good as a straight conversion from Captureshop - but in Captureshop, I did not have to touch the white balance.....). Thanks in advance for any suggestions on what I am doing wrong. Regards, Martin
What puzzles you about eXposure? I use it every day for tethered shooting and processing finished files for clients with no need for any other work in Photoshop usually. Sinar have made it quite easy to understand in my opinion - it looks similar to most other raw processors in structure, function and gui. There is a comprehensive help and people like your dealer or the friendly LL community are there if you need specific help with something. I don't deny it does lack some of the finer features of other processors and may be a little harder to fine tune your pictures to the degree possible in LR but it is fast and stable and worth getting to know. You can always request new features from Sinar in future versions - that is the only way they will know what people want.
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What puzzles me about eXposure? Well, not the basic functionality but the seeming absence of logic in some operations. An example: I take an exposure under tungsten light - I set the WB on the back to the "Tungsten" setting, I set the input profile in eXposure to the eMotion 75 Tungsten 2009 profile, and I also choose Tungsten as the WB setting in the eXposure processing pane. Why on earth is the image still yellow/orange? Why does the Kelvin reading stay at 5500 when I set WB in the eXposure processing pane to Tungsten? Makes no sense to me (of course I can move the slider to 2850 but by that time my confidence in the software or my ability to use it starts to evaporate. Another issue: why do the previews show severe moire (magenta/cyan edges) where there is none after I enlarge the image with the loupe tool?
I had other issues with the version of eXposure that came on the CD with the back - all images imported with a severe dark green cast, calibration was entirely counter-intuitive (still don't know if the software was applying my calibration settings only to one image or all subsequent images, unfortunately the 6 page parody of a "manual" that came with the software did not help); when I tried to shoot the calibration target the software sometimes refused to acknowledge that I shot an image (in the calibration window, after it prompted me to take a shot of the target, it did not react when I shot the image).
After I read your positive comments on eXposure here yesterday I downloaded the newest version from Sinar's website and actually managed to do some good conversions but still with the white balance issues outlined above (had to fix WB manually with the color picker tool, after that the resulting image was as good as a straight conversion from Captureshop - but in Captureshop, I did not have to touch the white balance.....). Thanks in advance for any suggestions on what I am doing wrong. Regards, Martin
Dear Martin,
the first thing you have to do, more important than setting "Tungsten" or "whatever" profile in your back or in eXposure, is to make a correct WB with a Macbeth or 18% neutral grey chart. Do your first shot with such a chart in the image and you will be able to calibrate for the available light, correctly. The profiles in the back are only average/default profiles and can give various results: I would never use them. Nothing replaces a right WB. Same with Captureshop, actually. You can then either click on this neutral grey chart with the "Manual WB" in the back menu, or later in eXposure. Doing it in the back will make sure that all following images will be neutral/white balanced. But you can do it later and in a batch process in eXposure, on all the images shot.
Then: there was effectively a "bug" in an earlier eXposure version, which made the green/magenta axis setting being to law in eXposure. That is now fixed since a while.
Previews with "Moiré": this is not Moiré, but simply a rough (sometimes pixelized) display of the image (preview) in order to make it faster to display. When zooming in the application calculates and processes then the full image quality.
I hope this helps.
Best regards,
Thierry
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Dear Thierry,
Thanks for your advice. Sure, I can shoot a Macbeth target at the beginning of every sequence - this works well for someone shooting in a studio, with constant lighting conditions. But I also understand that I should be able to calibrate eXposure, right? I understood the way this was done in Brumbaer (shoot one image of the target in daylight and a second one under tungsten, the software then interpolates between the two for the other settings; when doing conversions I can then choose the corresponding matrix to get reasonably close to accurate WB...). As I often shoot outside under varying lighting conditions, I would like to calibrate eXposure in a similar way so that it would get the initial processed image reasonably close to where it should be and not miles away, at least under one setting (let's say "Sunny" or "Flash").
So, to reword my question: can I get more consistent/accurate initial DNG conversions through calibration of eXposure, without shooting a color target every time? If so, what is the best way of doing that?
Best regards,
Martin
PS: I am still convinced that the WB slider in the processing pane should not stay at 5500K when I select the "Tungsten" setting but should move to around 2850K, could that be a bug....?
Dear Martin,
the first thing you have to do, more important than setting "Tungsten" or "whatever" profile in your back or in eXposure, is to make a correct WB with a Macbeth or 18% neutral grey chart. Do your first shot with such a chart in the image and you will be able to calibrate for the available light, correctly. The profiles in the back are only average/default profiles and can give various results: I would never use them. Nothing replaces a right WB. Same with Captureshop, actually. You can then either click on this neutral grey chart with the "Manual WB" in the back menu, or later in eXposure. Doing it in the back will make sure that all following images will be neutral/white balanced. But you can do it later and in a batch process in eXposure, on all the images shot.
Then: there was effectively a "bug" in an earlier eXposure version, which made the green/magenta axis setting being to law in eXposure. That is now fixed since a while.
Previews with "Moiré": this is not Moiré, but simply a rough (sometimes pixelized) display of the image (preview) in order to make it faster to display. When zooming in the application then calculates and processes then the full image quality.
I hope this helps.
Best regards,
Thierry
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Dear Thierry,
Thanks for your advice. Sure, I can shoot a Macbeth target at the beginning of every sequence - this works well for someone shooting in a studio, with constant lighting conditions. But I also understand that I should be able to calibrate eXposure, right? I understood the way this was done in Brumbaer (shoot one image of the target in daylight and a second one under tungsten, the software then interpolates between the two for the other settings; when doing conversions I can then choose the corresponding matrix to get reasonably close to accurate WB...). As I often shoot outside under varying lighting conditions, I would like to calibrate eXposure in a similar way so that it would get the initial processed image reasonably close to where it should be and not miles away, at least under one setting (let's say "Sunny" or "Flash").
So, to reword my question: can I get more consistent/accurate initial DNG conversions through calibration of eXposure, without shooting a color target every time? If so, what is the best way of doing that?
Best regards,
Martin
PS: I am still convinced that the WB slider in the processing pane should not stay at 5500K when I select the "Tungsten" setting but should move to around 2850K, could that be a bug....?
Dear Martin,
yes, you can "Color Calibrate" and create a color matrix, but the most important, to begin with and to get rid of your "strong" color cast which you seem to have, is the WB. After that, if the default color calibration does not fit your taste you can create your own one in eXposure, like in Brumbaer. But most of the time it is not necessary. Necessary is to shoot a neutral grey, at the beginning of a session. Even if the light changes a bit, it will not affect that much, unless the weather goes from sunny to cloudy, or else. But then simply re-shoot a neutral grey and that's it. Really not a big deal, and other backs do work the same way. That will for sure get you "reasonably close", as you put it, believe me.
A color calibration comes then in a SECOND step, not before making a WB, respectively to replace it.
As for the slider in eXposure being at 5500K, am sorry, but I have not tried the latest version of eXposure and can't speak without experience. I would contact Sinar to ask them the question.
Best regards,
Thierry
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Hi Martin,
As Thierry said the green cast problem that requires high tint settings to correct is now gone - it didn't affect image quality it just meant that tint needed to be around 70 instead of 0 for the average image. But the WB settings are pretty bad to be honest - I import pictures taken with the Sunny setting on the back and have a bizarre WB of something like 4327 for the temp and -37 for the tint.... who knows why - I have told Sinar and so has my dealer, but so far there is no firmware update in the back to make them more normal. If I click on the preset 'sun' setting in the WB preset of eXposure I get 5600 and 0 tint - surely the back should be the same. I don't know why the tungsten WB preset setting in eXposure is at 6000K instead of 3400 or thereabouts. But I don't use these presets anyway, and have shot my own Macbeth card targets for a sunny day, a cloudy day, inside my studio in daylight etc, and I use these along with a grey card WB with further custom fine tuning to my taste. I don't know anyone who uses the WB presets in LR for example and expects them to be accurate, but I do hear you on the back's presets. I encourage you to lobby Sinar to fix this, along with the low quality preview that shows screen moire. I recently complained to my dealer about this softness of the small size previews, and wished we could perhaps have a setting for higher quality previews at the base size. I think most computers are powerful enough now to deal with the increased processor demands required to produce a better preview in a short time, and even not, if there was a setting to change it for slower machines that would be good.
Ben
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Dear Thierry,
OK, I take your advice to shoot the color target at the beginning of every session. I look forward to the next time I shoot a regatta from a fast moving motor boat - I will wave the macbeth color target in the air in front of my lens and do my best not to get it blown away; perhaps I will even manage to get a focused shot of it if I ask the skipper to hold it for me :-). And next time I shoot my dogs I will train them to hold the macbeth chart in their mouth for a while :-). Maybe I should not be using a medium format digital back unless I want to change my priorities and start shooting models in a studio for some worthwhile magazine. Apologies for my sarcasm, the idea just amuses me (I know that under ideal conditions, shooting the target first of course makes sense and yes, I know I can do it before I get on the boat and before I start shooting my dogs.....)
To complete my education as to white balance - in the light of your recommendation, what use if any are then the preset color profiles in the back or in eXposure if they do not get me even remotely close to correct WB? If I set "tungsten" on my Nikon D3 and then process the raw files in LR/C1/NX2, the images do not show a heavy yellow cast (and I am not even talking about the custom camera-specific presets at the bottom of the Develop module in LR). Why can't I rely on the e75 / eXposure dream team at least to comprehend from my settings ("tungsten" dialled in on all fronts...) that the raw file should be processed with a WB of around 2800K and not 7000K or whatever other irrelevant setting the software chooses? Your reply seems to indicate (and reinforce my suspicion) that the WB presets in the back and in eXposure are totally dysfunctional - not like "not entirely accurate" but more like "miles off the mark, completely useless, only pretending to exist" - I find this hard to believe. My experience tells me this - if I shoot a color target at the start of every session, then I see no need to fine tune calibration - it is all there, three clicks in curves in PS and I am done, paste the settings across all subsequent files. My logic then suggests that (a) the inbuilt profiles in the back and eXposure should get me close to the correct WB in situations where I can't/don't want to use the color chart, then ( if I do not like these profiles, I can calibrate. This is how LR works for supported cameras, n'est-ce pas?
Curiously, I get no casts with Captureshop, it just seems to get the initial color balance very close, most of the time even under tungsten lights. It even gets gray clouds gray (and not blue) and fine dark structures (like aerials on roofs) are shown black, without magenta or blue edges (I have experienced all of the above issues with Brumbaer and the version of eXposure that came on the CD; have not tested the new eXposure fully yet). But of course Captureshop only saves Tiffs and offers only very crude adjustment tools, so back to eXposure and do my best to make it work.
Maybe this is a naive suggestion: Can't Sinar persuade Adobe to start supporting its backs in ACR and develop a few working custom profiles for Lightroom? Unlike studio photographers, I don't really need to shoot tethered and would welcome a more straightforward workflow, including the ability to download/process images on Windows computers.
Best regards,
Martin
Dear Martin,
yes, you can "Color Calibrate" and create a color matrix, but the most important, to begin with and to get rid of your "strong" color cast which you seem to have, is the WB. After that, if the default color calibration does not fit your taste you can create your own one in eXposure, like in Brumbaer. But most of the time it is not necessary. Necessary is to shoot a neutral grey, at the beginning of a session. Even if the light changes a bit, it will not affect that much, unless the weather goes from sunny to cloudy, or else. But then simply re-shoot a neutral grey and that's it. Really not a big deal, and other backs do work the same way. That will for sure get you "reasonably close", as you put it, believe me.
A color calibration comes then in a SECOND step, not before making a WB, respectively to replace it.
As for the slider in eXposure being at 5500K, am sorry, but I have not tried the latest version of eXposure and can't speak without experience. I would contact Sinar to ask them the question.
Best regards,
Thierry
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Hi Martin,
In my experience if you have a few saved calibration targets that will be perfectly fine. So one for sun, one for a cloudy day, one in the shade etc. Then just select these and apply them later when you import from CF card. I agree with you about the strange presets in the back - contact Sinar tech support and encourage them to fix it. But in practice you can just apply a setting to all your pictures as soon as you have imported them in a couple of clicks, so it's not a bad problem in my opinion. For example, to get you in the ballpark just apply a WB of 2800K to all your tungsten shots by making the first one 2800K then command-c that picture once selected in the contact sheet, select all, then command-v to apply the settings to all the pictures. That is a quick step and does the same as the back would have done anyway.
Ben
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Dear Thierry,
OK, I take your advice to shoot the color target at the beginning of every session. I look forward to the next time I shoot a regatta from a fast moving motor boat - I will wave the macbeth color target in the air in front of my lens and do my best not to get it blown away; perhaps I will even manage to get a focused shot of it if I ask the skipper to hold it for me :-). And next time I shoot my dogs I will train them to hold the macbeth chart in their mouth for a while :-). Maybe I should not be using a medium format digital back unless I want to change my priorities and start shooting models in a studio for some worthwhile magazine. Apologies for my sarcasm, the idea just amuses me (I know that under ideal conditions, shooting the target first of course makes sense and yes, I know I can do it before I get on the boat and before I start shooting my dogs.....)
To complete my education as to white balance - in the light of your recommendation, what use if any are then the preset color profiles in the back or in eXposure if they do not get me even remotely close to correct WB? If I set "tungsten" on my Nikon D3 and then process the raw files in LR/C1/NX2, the images do not show a heavy yellow cast (and I am not even talking about the custom camera-specific presets at the bottom of the Develop module in LR). Why can't I rely on the e75 / eXposure dream team at least to comprehend from my settings ("tungsten" dialled in on all fronts...) that the raw file should be processed with a WB of around 2800K and not 7000K or whatever other irrelevant setting the software chooses? Your reply seems to indicate (and reinforce my suspicion) that the WB presets in the back and in eXposure are totally dysfunctional - not like "not entirely accurate" but more like "miles off the mark, completely useless, only pretending to exist" - I find this hard to believe. My experience tells me this - if I shoot a color target at the start of every session, then I see no need to fine tune calibration - it is all there, three clicks in curves in PS and I am done, paste the settings across all subsequent files. My logic then suggests that (a) the inbuilt profiles in the back and eXposure should get me close to the correct WB in situations where I can't/don't want to use the color chart, then ( if I do not like these profiles, I can calibrate. This is how LR works for supported cameras, n'est-ce pas?
Curiously, I get no casts with Captureshop, it just seems to get the initial color balance very close, most of the time even under tungsten lights. It even gets gray clouds gray (and not blue) and fine dark structures (like aerials on roofs) are shown black, without magenta or blue edges (I have experienced all of the above issues with Brumbaer and the version of eXposure that came on the CD; have not tested the new eXposure fully yet). But of course Captureshop only saves Tiffs and offers only very crude adjustment tools, so back to eXposure and do my best to make it work.
Maybe this is a naive suggestion: Can't Sinar persuade Adobe to start supporting its backs in ACR and develop a few working custom profiles for Lightroom? Unlike studio photographers, I don't really need to shoot tethered and would welcome a more straightforward workflow, including the ability to download/process images on Windows computers.
Best regards,
Martin
Dear Martin,
You are right, and I said it, like Ben, the default in-camera profiles are not accurate, for whatever reason which I don't know. And yes, do contact Sinar to make them work on it. This being said, in-camera profiles are only DEFAULT profiles, made under certain light conditions, which (should) bring you close enough with the first shot, most of the time very close, but sometimes not.
And as said by Ben, yes you can do and save a few CC's and then select them according to the light with copy/paste
BUT I insist on the fact that shooting a grey chart at the begin of each session is a life-saver. If your initial light isn't exactly the same as the one you have shot your CC for, then you have no way to correct it accurately. The grey chart makes it possible to bring your image(s) to the exact values of "neutrality". That is why I do (did) never bother to use those in-camera profiles, accurate or not. I do understand that it is not convenient in some situations, like the one you have described (funny ), but I believe that it is possible without a big deal to quickly shoot such an image at the beginning.
Best regards,
Thierry