"True Colour" Scene File
 

Paulo Ciccone, one of our members and HD100 contributors, just emailed me a link to the results of his tests with a DSC Labs colour chart.
He has successfully calibrated for chart and created a "true colour" scene file recipe.

Here's the web page with the full article: http://www.paolociccone.com/hd100-calibration.html

A few people have emailed me asking about ITU-709 colour space match settings, and I haven't had the time or resources to create such a file. I imagine Paulo's scene file will fill that gap.

It is also interesting to note the results of colour cast on the default matrix settings. Some others have mentioned it before, but Paulo clearly demonstrated what is going on with the Cine matrix. It looks like it has a very warm response compared to the calibrated one.

Thanks to Paulo for the great article. You've inspired me to write up articles in html format!

Thanks Paulo for taking the time to perform this calibration.

I'm looking forward to trying these settings.

I'm glad you spent the time to maximize color space. I like the idea of leaving color correction for post production. For those who perfer not to, the JVC offers a lot of internal control.

I might have to break down and buy a DSC chart. You have to wonder how closely our cameras are calibrated.


Also, Tim thank you for this link.

Hey Tim.

Thanks for the sticky. Initially I tought about posting the article in the forum but it became soon to complex in formatting, with all the pictures and links. HTML was the logical choice. I used Adobe Go Live to format the page, my first attempt to use the program. I'm actually quite impressed with the flexibility of this application.

Take care.

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Paolo

You're welcome Steven. Hope it helps.

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Paolo

WOW very cool - thanks!
 

"A director must be a policeman, a midwife, a psychoanalyst, a sycophant and a bastard."
- Billy Wilder

Excellent work, Paolo.

One thing I found myself wondering: With the IRE range adjusted to the extremes of the DSC chart, just how "white" and "black" are those are corresponding targets on the chart? Wouldn't a scene with lighter or darker elements get clipped? For example, the black target on the chart compared to a piece of black velvet.

Thanks.

DSC has some detailed documentation on their website. Particularly interesting is a paper presented by their founder at a SMPTE conference. He's more qualified then myself to explain the fine points of colorimetry and calibration. My understanding is that their charts are calibrated to reproduce pure white and black and so, when properly lit and exposed, the chart should reach the maximum available for the camera.

Once you know that the camera is calibrated at the limits of its range you should set the zebras to warn you well before you reach those limits. Of course this could be problematic in a run-and-gun situation. I have my zebras set at 85-95%. Also, DVRack, the program that I use for monitoring, has zebras for light and dark areas.

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Paolo

That's a good question, and it should be noted that Paulo's scene file does not utilize knee or black stretch, so the dynamic range is much more limited than the cinewide setting. So yes, with knee set at 100%, the whites will clip much earlier than with knee set at 80%. There will also be less shadow detail than if black stretch were increased.

I've chosen to implement Paolo's color matrix, saturation, and gamma settings while retaining Tim's black stretch and knee tweaks.

I'll see how it goes.

Tim, my understanding of the knee function is that it generates a smoother transition between the highlights when clipping happens. In doing this the knee circuitry actually reduces the amount of data that is recorded. It has a nicer look but the range is more limited with the knee active.

In a run-and-gun situation you might want to use my configuration with a 90-95% knee in order to stay on the safe side. In a controlled environment it actually gives you more range to disable the knee and keep the levels in check.

Of course I could be wrong :)

I decided to re-run my test and verify what really happens with the knee enabed.

A picture is worth 1000 words so here are several snapshots of the WFM from my config file with knee at different values:

Knee 100%
Knee 95%
Knee 90%
Knee 85%

We can see a pretty strong flattening (clipping) of the highlights as we increase the knee value.

I also took some snapshots of the black stretch. The knee is left at 100% while increasing the stretch value. Use the "Knee 100%" image as a reference for black set to "Normal".

Stretch 1
Stretch 2
Stretch 3

It seems to me that the stretch causes a whole shift to the upper range and that's why I didn't use. It does make the black chip look more round, but it affects a lot of other things too. Again it is perfecly fine as a look but my goal was to get as close as possible to 1:1 representation.

BTW, Tim, big mistake on my side about the color shift on the Cinelike and your CineWide config. I did't realize that switching to another config changes the white balance. I balanced at the beginning of the test and never changed it, assuming that the camera kept the 3200K value. My apologies, I'm gonna retake those samples after setting WB at every switch. I'll update the article asap.

Take care.

--
Paolo
http://www.paolociccone.com

That's cool Nate, I'm eager to see your conclusions.

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Paolo

I'd noticed that and wondered about the white balance. How about white balancing and then getting a reading. Now place the reading on a preset and rerun the test for the cinelike gamma. The colors won't punch as much as the standard gamma but they transition more smoothly. Excellent work and I like your scene file. If you get a moment can you load my scene file and take a look at if for me on your chart?

Click here for scene file or Here for screenshots.

Thanks,

Yeah, I would suggest using preset 3200K if you already confirmed that your lights are exactly 3200K. The way the scene files record EVERYTHING, including the value set in the A & B white balance is frustrating. I didn't realize it at first either.

Not quite. The dynamic range of the CCDs is much greater than the dynamic range of the video data encoded to tape or of a standard video monitor. Your chart represents probably only about 4 stops of exposure. You should set it in front of a window on a bright day and compare the knee settings. You'll find that the knee brings the wider dynamic range of the CCD into the effective range of what we can record to tape. There is a cost however, and you've shown it in your knee tests. Values that were previously above the knee point get shifted down. Therefore the white chip is no longer 100% white, but you can now expose detail in white values brighter than the white chip. For the most part the knee should be able to extend the dynamic range at least 1 stop, maybe 2. This gets us closer to the way film negative handles highlights, (but not that close.)

Black stretch works essentially the same way, but on the other end. It takes a bit of the lower mid range to use in the shadows so that the blacks are not entirely crushed. Black stretch should not affect any values in the mids or highlights.

Talk about potential for embarrassment :) I reshot everything and updated the web page. Instead of using the preset at 3200K I switched to a different config and white balanced every time. Much better now. Sorry for the mistake.

Interesting stuff about the knee and black stretch. I'm still not convinced that the knee doesn't cause data loss but I'll defintely try to get some real life test as you suggested.

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Paolo

Hi Stephen. I'll be glad to look and test you scene file. I'll probably do it tomorrow, today I had to re-shoot the whole thing ad I need some rest :)

I'll post an addendum to the article with your scene file asap.

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Paolo

Hi Paolo,

I have a question for you, since you used HDVrack to calibrate the DSC chart. When I output the build-in SMPTE Colorbars of the HD-100 into HDVrack, the colors are not in the 'spot' on the vectorscope. They have a considerable offset.
As far as I can follow with the HDVrack is that the original software has been made for DV which is using another colorspace then the HDV ITU-709.
I asked this question to the Serious Magic guys if they use the 709 color space or not when using HDV, but their forum if offline already for several weeks. So I have no feedback back yet from them.
My question now is: When you calibrated the DSC chart on HDVrack, is it now right or not considering the build-in color bar is not showing up right.
My 'real' Philips Vectorscope is in the repairshop, so I cannot verify.

Marc do you have the HDV pack?

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Paolo

True Colour Scene File
 

This is my first post to the forum and I must say that I am very impressed with how you guys are prepared to share your valuable knowledge and experience with us lesser mortals.
Thanks to Paulo for your scene file. I used your scene file settings to set up my HD100 at the weekend and shot some test footage to see the results. The colour reproduction is very accurate to the props I used in the scenes which were shot in my small studio using my stills lighting rig which are flash units with controled modeling lamps. I also shot some exterior shots and bearing in mind that it was a damp, overcast day the footage was very clean and had no colour casts that I usually experience under these shooting conditions. I must say I liked the resulted image quality; I have been playing around with the Cine Gamma scene settings and found that in some conditions whites and blacks seem to suffer from strange colour casts. Like Paulo I want to see as accurate a colour rendition as I could get so what colours I see with my eyes is reproduced on tape and carryout any adjustments to look in post.
Unfortunately I don't have enough knowledge to post any of my test footage here for you to see; as soon as I get it together I will certainly share my results with you; especially as I was also testing out my new Fujinon wide angle lens which I know from various posts that the community is eager here about. From my point of view this new lens improves the picture qulaity beyond any of my expectations; the images are a lot crisper and sharper than on the stock lens. There is also a lot more control for DOF. I believe it's well worth the investment I made and has confirmed my belief in this camera as a serious bit of kit for the independant film maker, especially when you consider it's price.

Please forgive me for my descriptions as I am not a video techy; I do not work professionally in the video industry, I work in the film industry making armour and props and it has always been my ambition to get behind the camera to produce my own independant features. This was the main reason I chose the HD100 after trying out a demo unit. I was struck by it's picture quality and it's filmic look to the footage. We have already shot our first short and are halfway through editing so I am getting to know the camera's strengths and weaknesses. I must say I love the camera and have been glued to the posts on this forum so I can get the best out of this wonderful camera. I am not, in any way a video tech, but I am eager to learn. Unfortuanately, I use FCP5 in my workflow so have not been able to capture my footage nativly, as yet. I am using a Kona card and converting to another codec.

This is a great forum and now I have actually dipped my toe in the water, I am sure that I will be a regular contributor.

Paolo, yes I have the HDV pack. You want me to do some tests?
I don't have any DSC chart though...

No Marc, I was just asking to be sure that you have the HD Monitor option avalable. It's my understading that the HD pack implements the right colorspace for HD monitoring. I didn't test the camera bars with DVRack but I'll do it soon.

--
Paolo

You're very welcome. Glad to hear that it works for you too.

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Paolo

Hey Steve.

I copied your file directy to my SD card, configured the camera to the same values of my test by using my configuration as a reference. I then loaded your file, set WB and recorded 7 seconds of chart and took the same snapshots I took with my previous test.
Your files are here:

7-second .m2t clip
Snapshot used for histogram
Histogram
WFM and VScope

Hope this helps.

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Paolo

Thank you for doing that. Your chart reveals what I was trying to accomplish. Pulling the reds down. I think the red's are hot in all my RGBY separations. Now with this scene file the skin tone is better (to me).

Lattitude zoomed to 88mm
Skin tone on a fair person.

Thanks for doing that...

24p?
 

Lattitude zoomed to 88mm
Skin tone on a fair person.
...............................................

For those two files: was that shot in 24p mode?

You're very welcome Stephen.

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Paolo

Paolo:

Have you updated yet the article including Tim's recommendations/suggestions?

Thanks,

Luis

30p mode...

Hi Luis.

Yes, I reshot all the samples after setting the WB for each file. The new version has been posted Saturday so the current snapshots, clips and histogram charts are the correct one.

One thing that I didn't mention is that I did some additional tests for the sharpening control. Im quite convinced that the disabling the sharpening blurs the images a bit while keeping the sharpening at minimum seems to be the right setting in order to get a nice sharp image that is still soft enough to not look like video.
I also checked the effect of incremental sharpening with a WFM and you can clearly see the addition of video noise.

--
Paolo
http://www.paolociccone.com

Thanks!
 

Paolo,

Thanks a lot for this great effort from your part, specially because you have been willing to share all the information with this cybercommunity.

In terms of white balance: you use the settings and then WB, or WB and then load the settings? I remember that that was an issue brought by Tim with his efforts. If I do not recall incorrectly, I think we needed to load the setting, then do the WB. I assume is the same you have found...

In regards to the sharpening, what is the setting you particularly recommend?

Again, thanks!

Luis

Paolo,

FYI, The DVRack software guys confirmed there is a color space problem in the HDV mode for the HD-100. It uses 609 currently. It will be fixed in the next patch.

Just a small contribution to a community that helped me so much :)

That is correct. The problem is that the HD100 stores the values of the A and B WB presets together with your configuration. If you, for example, had A WB at 4300K and B WB at 3200K when you saved a configuratio to the SD card, they will be restored when you reload that configuration. I didn't realized it the first time I calibrated the camera. BTW, WB is also affected by the ND filter so be sure to reset it every time *anything* changes in your setup.

Just a step above the "OFF" position, it's labelled "MIN"

--
Paolo
http://www.paolociccone.com

Marc, good to know and a little disappointing. Did they say if there's an ETA for the fix?

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Paolo

Nope, They said to wait for the fix. At the time of the implementation of the HDV, they didn't had a HD100 to testout. They used another camera which apperently did not have the right HDV specifications and used another color space.
They are going to try if they can make an 'auto' color space setting, otherwise it will probably a menu setting they will add.
I hope all your work was not for nothing now.

I don't think so. I'm rechecking the settings with the FCP VScope. I'm trying to find a way of feeding the camera signal to FCP with the minimum amount of "jumps" :)
I see that Serious Magic is Folsom. I could drive theretoday and bring them my HD100 for testing. Do you know the name of your contact in Serious Magic?

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Paolo

Marc, thank ou for your concern. The Gamma, black and master black settings are not affected by this. I switched the camera to DV output for FireWire and cheched the color matrix and it's fine. There is a good article about the different color spaces and compensation for checking 709 on NTSC monitors at http://www.dsclabs.com/product_reviews.htm Check the "Image optimization" document.

My configuration is still the closest to 1:1 representation for color, if anybody can get any closer I'll be happy to change my parameters. As it stands now I believe that this setup is superior in accuracy and color rendering than the stock scenes.

For the first time, since I bought this camera, I'm getting the vibrant colors and image quality that I was expecting. I believe that, if you shoot the same scene with, say, Cinelike24pHD and my config, you'll be able to verify the difference by naked eye.

Ciao!

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Paolo

Yes I tried your settings, the colors make indeed a difference :-)

My contact at Serious Magic is Benoit Ambry about the subject.

Serious Magic is Folsom... I didn't knew that. Great guys at Folsom.
I worked with them at Barco Belgium two years ago.

Paolo, in an earlier post someone said that they would use your color settings, but use tim's black stretch/knee tweaks. would this through off the colors drasticly? And are your settings acceptable for film out?

No, mixing my color matrix settings with Tim's gamma and black stretch should not change the color result. I don't want to start arguing about this but I believe my settings, as published, will give you more latitude. But make your own judgement. Take a look at the results from the WFM and vectorscope that I publicshed. Your goal is to make the white chip register at 100 and the black chip at 0. If you look at the result of my gamma/black settings you see that it's pretty damn close to that.
Shoot the same scene with both settings, bring them into your NLE and check the result on a good monitor. Use what you like the most. Using the SD card it's a snap to switch between configurations. Keep in mind that I configured the camera for a "neutral" look. My target is to use all the limited bits available to capture as much as possible, leaving the job of altering and clipping those bit in post. Your approach could be different.

Depending on your type of shooting this could be right or no. You mentioned filmout and so I guess you're gonna shoot in a controlled environment where you can check the light levels. In this case my setings will give you the wide latitude , I believe close to the maximum available with this camera.
The one setting that you might want to change is to switch the detail to "MIN".

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Paolo
http://www.paolociccone.com

Paolo,
Have you done any tests with the detail setting?

I'm interested in determining the effects of this control.

To me it appears to actually go beyond turning off any artifical enhancement. The image appears to be blurred

Hi,

DSC also makes a skin tone chart. Just wondering if you got the set of DSC charts or the single chart. The reason I ask is because the "true color" setting seems to make skin tone too rich and the suttle nature of gradients surrounding facial features seems to be missing. Browns and pinks are too saturated.

What are you findings where skin tone is concerned?

BTW: Don't get me wrong. Your work is excellent. I was wondering if you see the same thing I do where skin tone is concerned using the "true color" scene file.