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-   -   TrueColor configuration for XH A1 (https://www.dvinfo.net/forum/canon-xh-series-hdv-camcorders/116993-truecolor-configuration-xh-a1.html)

Paolo Ciccone March 20th, 2008 12:43 AM

Quote:

Originally Posted by Dirk Bouwen (Post 845121)
hard to find any similarity between both approaches - which I theoretically should expect, to certain extend in the pure color settings & matrices.

It all depends on the tools used. I don't know what Wolfgang used to calibrate the camera but different chart are going to give different results. It's interesting that Dennis Wood was able to reproduce the values in the monitors when dialing the same settings and using the same style of chart, although he employed the backlit version. This gives a measure of reproducibility and objectivity about TrueColor.

Quote:

What I question a bit, is the theory about sharpness.
While we don't have information about the working logic of the sharpness circuit of the A1, pretty much all video cameras use the same approach. They take a perfectly fine signal and add "detail" by drawing darker pixels in the areas of high contrast. The artificial "enhancement" of video images is well documented by several sources including Scott Billup's "Digital Moviemaking" and Stu Maschwitz "The DV Rebel's guide". The senosr of the camera, if the lens is in focus, will capture a perfectly good image. It might look a little soft but the sharpening can be added in post using After Effects or similar programs, generally leading to better images. This is, of course, assuming that you have the time to post process the clips. If you don't have that luxury then dialing is a couple of points of sharpness is perfectly fine but generally tye factory levels are way too high.

Quote:

I also read something about the dynamic range of the A1 versus the JVC
In my testing the JVC's range is wider, as expected since the camera is $2000 more than the A1. The XDCAM can turn even more, around 9 fstops, again, perfectly expected given the price range of that camera.

Quote:

With a clear pitch towards filmic settings, and with also a lot of respect to the searchers for the perfect neutral preset, I doubt this is really the aim of most A1 users.
Actually I got the commission to develop TrueColor A1 exactly by a client who is filming with a couple of these cameras. The goal here is to obtain the most out of the camera with the least amount of "bias". This approach is generally preferable if you try to develop a specific look for narrative work. This is because you will have all the power of your grading suite to work on the full spectrum of colors. If you shift the camera to a part of the spectrum and drop a series of wavelengths in order to create a look in camera you will never be able to regain them later on. On the other hand you will be able to shift everything as radically as you want in post and then recover and fine tune at your liking.

TrueColor is just another tool in the arsenal of the shooter. BTW, the name was given to it by one of the moderators of the JVC forum, not by me. It just stuck :)

Paolo Ciccone March 20th, 2008 12:46 AM

Quote:

Originally Posted by Brandon Freeman (Post 845139)
I'm looking forward to trying this preset.

One thing -- I have found that turning the Master Pedestal down to -9 actually clips out some black areas (as in, I can't pull that information back up at all).

You know, you are actually right, I meant to raise that value a couple of notches but I forgot. The initial setup for the DSC chart asks to move the master black so that the black chip falls in the zero IRE point but the chip is, of course, partially reflective. A more accurate configuration would be to keep it around 1-1.5%. Try at -7 and let us know.

Rudy De Smedt March 20th, 2008 05:27 PM

Another blue ...
 
Hello,

also being a new owner of a A1 I am looking for good presets. This TrueColor looked very interesting to me. When applying it I also remark much of blue.
I saw some other people have the same problem. Any solution/suggestion how to correct this ? (I have no calibration equipment)

Greetings,

Rudy

Jack Walker March 20th, 2008 06:31 PM

Quote:

Originally Posted by Paolo Ciccone (Post 845409)
You know, you are actually right, I meant to raise that value a couple of notches but I forgot. The initial setup for the DSC chart asks to move the master black so that the black chip falls in the zero IRE point but the chip is, of course, partially reflective. A more accurate configuration would be to keep it around 1-1.5%. Try at -7 and let us know.

Thank you for this correction. I also had found this with the black and wondered if I had set something wrong.

Bill Grant March 20th, 2008 06:32 PM

Hey All,
I did some testing with the true color today, and I noticed that the color changed so radically, that I had to re-white balance from other presets. Once I did, I found that the blue went away. I also raised my sharpening to -6 and the ped to -7. I think it looks good. I also seemed to get a light boost somehow. This one might be a winner. I will post results when I get them.
Bill

Dennis Wood March 21st, 2008 12:43 AM

Dirk the approach using charts like the ChromaDumond makes a lot of sense and is well established in industry. The colours in these charts are spectrophotometrically accurate and comply with SMPTE 274M colorimetry. There is really no better way to calibrate a camera as human perception, LCD calibration, monitor calibraton etc. are all taken out of the equation. It's not perfect, but I've yet to stumble over a better solution.

Dirk Bouwen March 21st, 2008 11:47 AM

I hear what you're saying, all, and really: it is very interesting.

I was one of the first wave of A1 owners, and have been playing with quite a few presets ever since then (DVInfo was the major focus for me, but also Wolgangs' website was quite interesting). Like probably everyone with an A1, I spend quite some tapes and hours, capturing, comparing, ... in establishing a shortlist of presets, that could serve my purpose - because after all, not all shooting purposes are the same.

Also true - like probably again quite a few A1'ers, I've sometimes been disappointed after I shot the final footage, even after a lot of experimenting. Looking for something more cine-look, I went over the DVX-emulations towards, VIVIDRGB - and this one in particular - put on a pedestal by some in this forum - has entirely mislead me, because greens suddenly go to... brown. Something I experienced in the field, and I don't say I'd spoiled my footage, but I was not happy either, this type of exaggeration was one street too far.

The increase in gain by applying presets is not really new - it's not so much surprising me.

You convinced me to do some further testing with this preset. Paolo, I'm sure you did a great job, let there be no discussion about this, thank you very much to set direction.

Bill Busby March 21st, 2008 01:00 PM

Dirk, I've noticed your posts before regarding green looking brown. I've never seen this at all.

The only weird thing I've seen is with certain shades of purple being blue, no matter what preset and/or WB is used. Wolfgang's site at one time had something about this but I can't locate it anymore.

Lonnie Bell March 22nd, 2008 10:06 AM

I will play with this setting this weekend.

Bill Grant - looking forward to your findings on your adjustment and maybe a nonCC screen grab or two...

Pat Reddy March 22nd, 2008 10:28 AM

Thanks Paolo for this new preset (and everyone who has been tweaking it and Taj and Dennis who coded it for us). I watched a PBS show on Ansel Adams this week. They focused a lot on how his goal with large format landscape photography was to acquire a film negative with all the latitude he needed for artistry in the dark room.

Of course the XH-A1 will never have the latitude of film, but I am excited about emulating this general approach with the A1.

Cheers,

Pat

Phil Taylor March 22nd, 2008 11:24 AM

True Color Preset
 
It is interesting that Adams and Mourtensen (http://thescreamonline.com/photo/pho...mentnotes.html) used very interesting Post techniques to arrive at what they considered the best work they could command. I studied Adams and became fairly good at achieving his look through darkroom practices, in photographs, which I love. Color, not so good but in B&W the darkroom is your slave once you are a little experienced in the dillutions and timing techniques. I also did, or attempted to reproduce some of the Mourteneen effects but the results were not nearly as predictable and some were good while some were terrible. As for video, especially digital video, one has a fair amount of latitude in the post process. But it takes a lot of time and work to achieve the manipulated results one is looking for. But I really enjoy all of this, the struggles we all go through in pushing the envelope to achieve a desired result. Great A1 stuff here and right on. Shoot a good non manipulated negative (positive) and do with it what you wish in post.

Dennis Wood March 22nd, 2008 05:17 PM

Paolo doesn't own an XH-A1, otherwise like the JVC (an excellent write up on initial HD100 colour tuning, then tweaks after field use on his website), I'm guessing he'd tweak the living daylights out of this one. I do have an XH-A1, and the rear illuminated DSC OSG's, but I'm much lower on the learning curve when it comes to the myriad of parameters possible. Like Paolo, I share an intense interest in wringing all that is possible out of the digital realm.

To complement Paolo's work we'll be doing a similar exercise with the HV20, XH-A1, EX1, and HPX500 looking at color rendering, dynamic range, ISO rating, and resolution. This is more to characterize these cameras in terms of adapter use, but the results should be interesting.

There is no question that the XH-A1 (and all the Canon cams up the scale) as well as the Sony EX1 offer an amazing feature set to tune the camera's beyond most user's understanding. What I can offer to do is take requests from this thread with regard to changes to the preset and see what effect they have on the waveform and vectorscope. We'll start the test series likely this week.

Bill Grant March 22nd, 2008 08:14 PM

Here's some experimenting I've posted on vimeo. Enjoy...

http://www.vimeo.com/user405235/videos

Dennis Wood March 22nd, 2008 09:24 PM

Bill what did you think? I have to admit that although the truecolour was the darkest, it also looked the best to me. One thing that I would look at changing is the black setting to expand the blacks a bit from their crushed level in the preset. It would be interesting to try this in post and see how it looks.

The VX2100 is still the king of the affordable DV cams in terms of light sensivity IMHO, but that barrel distortion at full wide is huge!

Paul Mailath March 22nd, 2008 10:03 PM

[QUOTE=Dennis Wood;846910I have to admit that although the truecolour was the darkest, it also looked the best to me.[/QUOTE]

I thought so too but surely the point of the truecolour preset is to retain the maximium amount of information so the image can be altered in post therefore an 'in camera' comparison is not valid.

In fact while comparing any other preset on any one or a mix of camera's we are comparing a 'finished product' (an image with little work to do in post) whereas the truecolour preset is set to give the best raw image which theoretically can be manipulated in post to give a 'better' finished product.

in rereading this it sounds like I actually know what I'm talking about - that's highly unlikely, it's just my limited understanding of the preset and how it works


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