XL vs. XH Custom Preset adjustment scales

[Jay Stebbins]

On the H1 the presets for Color gain and Matrix were on a "-9 to +9" scale, correct? The A1/G1 is on a "-50 to +50" scale.

Is the range the same with many more steps on the A1 or has the range been expanded? I ask as I am fully engulfed with the presets right now. I unfortunately do not have access to a H1. I have been playing with the presets from the H1 library.

So I am trying to ask... If the Color Gain on the H1 was set at 3 would it be 16 or 17 on the A1?

I am also assuming that presets like coring @9 on the A1 were also 9 on the H1.

Thanks,
Jay

[Chris Hurd]

Thanks for starting this thread. You and I have the exact same interest and ever since I posted the XL-translated-to-XH custom preset files, I've been meaning to put this before the group to get some feedback and corrections.

First of all, the preset files that I posted are borrowed from our XL H1 presets download library, and all I've done is to make a rough translation in order to get some XH-compatible CP files circulating around here. However, while these particular custom preset files work perfectly in an XH camera, they're not entirely accurate to the original XL versions. For example if you put Steven Dempsey's PANALOOK or DISJECTA custom presets in both an XL H1 and an XH A1, they're not going to match.

So I'm asking for help from you guys to assist with finding the tweaks which actually will match up the XL and XH versions of any given custom preset.

And I'm fairly certain that the process is primarily just a matter of finding the XH preset that will match it to the default look of an XL H1. It's important to note that the XL and XH cameras do not match each other right out of the box. You think they would, because they share the same CCD block and Digic DV HD image processor. But they don't. So we need to quantify exactly how they're different and develop the required presets to get them to match. Therefore it would help if we had the flip side of a matching XH preset too -- that is, an XL custom preset that would match the default look of an XH camera. Once that's established, the rest of the work, which is the process of matching any given XL preset to its corresponding XH preset and vice versa, should be fairly simple.

In fact I think I have most of that work accomplished already -- assuming that it's correct, hopefully you guys can verify whether it is or isn't -- and that procedure is outlined below.

First we have to look at how the Custom Preset parameters compare between the XL and XH camcorders. This will focus on the XL H1 and we can adapt it to the XL2 later.

The list of adjustable parameters within the Custom Presets menus in both the XL H1 and XH series camcorders is identical. However what's dissimilar about them is that the scale of adjustment for some of these parameters is different between the two series of cameras (while the scales of certain other parameters remain unchanged). So let's look at what is the same and what is different between the Custom Preset parameters in the XL H1 and XH series cameras. And that's pretty simple: most all of the color adjustment parameters have changed, while the other non-color adjustments remain the same.

Custom Preset adjustment parameters unchanged between the XL H1 and XH series:

GAM Gamma
KNE Knee
BLK Black Level
PED Master Pedestal
SET Setup Level
SHP Sharpness
HDF Horizontal Detail Frequency
DHV Horizontal / Vertical Detail Balance
COR Coring
NR1 Noise Reduction 1
NR2 Noise Reduction 2
CMX Color Matrix
CPH Color Phase

The preset parameters listed above comprise the basic image setup adjustments, as well as the various image sharpening and noise controls. The only color adjustment parameter which is unchanged is the Color Phase scale. It's basically just an overall hue control which will shift the image either red or green. Like all of the other color adjustments in the XL H1 custom preset menu, the CPH control is on a scale of -9 to +9. However, all of those other color adjustments are on a different scale in the XH series cameras.

Custom Preset adjustment parameters now changed between the XL H1 and XH series:

CGN Color Gain
RGN Master Red Gain
GGN Master Green Gain
BGN Master Blue Gain
RGM Red-Green Matrix
RBM Red-Blue Matrix
GRM Green-Red Matrix
GBM Green-Blue Matrix
BRM Blue-Red Matrix
BGM Blue-Green Matrix

The preset parameters listed above comprise the basic color adjustments available in the XL H1 and XH series camcorders. In the XL H1, each of these parameters is adjustable on a scale of -9 to +9. In the XH series camcorders, the scale for these parameters changes to -50 to +50. Plus, the total range of adjustment for each of these color controls is greater than it is on the XL H1.

So the question becomes, what is the relationship between these two scales (XL vs. XH), and how do you translate an XL H1 color preset over to an XH camcorder? I think I have the first part of this question figured out. I've used it to provide a partial answer to the second half of this question (the full answer won't be known until we've figured out how to match the XH to the default look of an XL and vice versa).

Jay wanted to know if the XH range is the same as the XL but with many more steps, or has the range been expanded. The answer is that the XH range has indeed expanded over the XL range, and also there are now many more steps in the XH range than there were in the XL range.

Continued in next post...

[Chris Hurd]

...continued from previous post:

At first glance, when you look at the two different scales of -9 to +9 and -50 to +50, it might seem a little confusing as to how they can relate to each other. But when we take into account the increased range of the XH series scale and how it directly compares to the XL range, it actually begins to make very good sense. The key is understanding the relationships between the ranges. Canon USA has given us that information, and that's what we'll use as the basis for finding the formula to translate an XL series Custom Preset into an XH series Custom Preset. Canon USA states that the range of adjustment for the color preset parameters on the XH series camcorders is 140% of the XL H1.

Basically this means for any Custom Preset color control, the range of adjustment on the XH A1 and G1 is forty percent greater than the corresponding control on the XL H1. Since the adjustment scales go in two directions (either greater than or less than the default "0" position), we can assume that the forty percent increase in range means twenty percent in each direction from the center default starting point.

[ XH scale ] equals 140% or 1.4 times [ XL scale ]

[ XH scale ] equals [ XL scale plus 20% in each direction up or down from the 0 position ]

If we're going to express the XH scale as 140% of the XL scale, then we also need to be able to express the XL scale as a percentage of the XH scale. This is important because since the XL adjustment range is less than the XH adjustment range, we should therefore refer to it as a percentage of the XH adjustment range. And once we refer to the XL range as a percentage of the XH range, then the process of transferring one scale to the other becomes remarkably easy. So, to express the XL scale as a percentage of the XH scale, for the sake of figuring a percentile we'll refer to the XH as a value of 100. We know that the XH is 140% of the XL, so the question is, 100 equals 140% of what number? And that number is 71.5.

100 equals 140% of what number? Answer: 71.5, because 71.5 + (40% of 71.5 or 28.5) = 100

Notice that the math is a little rough! 40% of 71.5 is actually 28.6, and when you add 28.6 to 71.5, you get 100.1, not 100. But this doesn't need to be exact, and we can't dial in fractions of a Custom Preset adjustment step anyway. So for the sake keeping things easy, we're going to compromise and shave off a tenth of a point and simply say that if we put the XH adjustment range on a scale of 0 to 100, then the corresponding XL scale would be 0 to 71.5. In fact, let's make things even easier and leave everything in whole numbers. Then the corresponding XL range of adjustment would be 0 to 72. You'll see how convenient this simplification is in a moment. For now, we have an XH range that we know to be 140% of the XL range, and from that information we're able to determine that the XL range is roughly 72% of the XH range. Now let's convert some scales.

The XH color preset adjustment scale of -50 to +50 now begins to make a lot of sense. It's basically a 100 step scale, and that's what percentages are all about. So, using a 100 step scale of -50 to +50 for the XH range, and knowing that the XL range is 72% of the XH range, we can plot the XL range relative to the XH range using the XH scale of 100 steps. And thanks to that 100 step scale, this is pretty easy to do. 72% of 100 steps is 72 steps. Going in each direction up or down from the center default "0" position on the XH scale in 72 steps, the XL range is -36 to +36. We've allowed for the 40% increase of the XH range. The XH range of 100 steps (-50 to +50) is 140% of the XL range of 72 steps (-36 to +36) on the XH scale.

All that's left is to convert the XL range from the XH scale to the XL scale. And look how easily it fits: -36 to +36 converts very well to the XL scale of -9 to +9. Obviously, every step on the XL scale equals four steps on the XH scale (36 equals 9 times 4).

Therefore when translating an XL H1 Custom Preset color adjustment to an XH equivalent, you limit yourself to using plus or minus 36 steps of XH custom preset adjustment scale to accomodate the limitations of the XL range relative to the XH range. And you multiply the XL preset number scale by a factor of four to get the equivalent amount on the XH preset number scale.

XL color preset value of + or -1 equals an XH color preset value of + or -4
XL color preset value of + or -2 equals an XH color preset value of + or -8
XL color preset value of + or -3 equals an XH color preset value of + or -12
XL color preset value of + or -4 equals an XH color preset value of + or -16
XL color preset value of + or -5 equals an XH color preset value of + or -20
XL color preset value of + or -6 equals an XH color preset value of + or -24
XL color preset value of + or -7 equals an XH color preset value of + or -28
XL color preset value of + or -8 equals an XH color preset value of + or -32
XL color preset value of + or -9 equals an XH color preset value of + or -36

However there are at least two problems with this technique. First, it doesn't take into account the fact that the default image of the XH series camcorders does not match the default image of the XL H1. Therefore the simple conversion factor of 4 color steps in the XH color presets to 1 color step in the XL color presets does not produce an accurate match between the two cameras. What's missing is the neccesary XH custom preset tweak to get it to match the XL default image. Once that's been determined, then it should be a simple process of getting the colors aligned using the 4:1 ratio in adjustment steps as noted above.

The other problem with this technique is a curious matter regarding the CGN Color Gain parameter. We've just established that we should impose a limit of plus or minus 36 steps on the XH scale of -50 to +50 if we want to emulate the limited range of the XL H1. In other words, if we crank up the Color Gain on the XL H1 to a setting of +9 and we want to duplicate it on an XH camcorder, then we should dial in a setting of +36 (let's ignore the fact that we still need an XH tweak to match a default XL image). If we dialed in a Color Gain setting of +50 on an XH series camcorder, that should represent a 20% increase in color saturation over the XL H1 (because the XH series color range is 140% of the XL H1, or an additional 20% in each direction up or down from the mid point). The problem lies in the down direction. On the XL H1, a Color Gain setting of -9 is completely devoid of color. The color has been dialed out all the way, so that you're now shooting a B&W monochrome image. That setting of -9 to get B&W on the XL H1 should equal a setting of -36 on an XH series camcorder. But of course it doesn't. Setting a Color Gain of -36 on an XH camcorder still shows color. Color information doesn't disappear entirely until you've dialed the Color Gain all the way down to -50. While you might expect it to work that way, it does sort of throw off the notion that the 40% increase in color range is split evenly above or below the zero setting middle point for the Color Gain parameter.

Perhaps the key to matching an XH camcorder to the default XL H1 image lies in the Color Gain preset? It's time to examine the color output from both XH and XL series camcorders using a vectorscope. I guess that's where this is heading next.

Suggestions, corrections, disputes, disclaimers, refutations etc. are strongly encouraged at this point!

The attached image is a graphic which illustrates the differences in CP adjustment scales. Click to see it big!

[Jay Stebbins]

Well done...

Out of courtesy, I am going to wait a few days before I ask my next question.

I believe Disjecta is getting an A1. I am sure he will be tweaking his own presets. I have a feeling he will be able to add some more insight to this.

Chris, thank you taking the time. I am going to build another preset with the conversions, and compare the two. I unfortunately don't have a XL-H1 to make the more important comparison for this quandary.

Thanks again,
Jay

[Chris Hurd]

As usual I used way too many words. I should find a way to boil all that down into three or four paragraphs. What it all comes down to is that the presets in the library that I uploaded the other day do not match their XL H1 originals, and I could use some help to get them properly translated.

[Raymond Toussaint]

Thanks for the effort Chris!
It is good to be done, people already talk about 'the A1 presets" that is the unconverted ones. They forgot the understanding that these are original XL sets.

It is also a question for the left or right part of the brain, are you translating by math or by emotion? Today it is math, but remember that the colorsignal does not has a linear gain during the proces.

[Jay Stebbins]

Horizontal Detail Frequency & DHV Balance

Can anyone explain what exactly this is and how do you use it your advantage properly?

The next question will be about the three gamma curve settings and their relation to intended output/delivery... Whether it is just or a look or does it have some importance with the gamma curves on tvs and projectors?

[Jay Stebbins]

Today i shot some footage with the retooled preset called HVX from member Benton

Gam:1
Knee:Low
Blk: Pressed
Ped: -5
Set: -2
Sharp: 2
Hdf : H
DVH: 0 (it should have been set to 2 or 3)
Cor: -2 or -3
N2 1&2: off
Cmx: 1
Cgn: 5
Cph:0
Rgn:2
Ggn:1
Bgn:2
everything else is O

I reset the following
Cgn 20
Rgn 8
Ggn 4
Bgn 8

I think I like the original setting for my tastes. But then again, I am looking for a look for my project.

The beginning of this sequence goes between the two presets, then after the first transition I use the preset I like better. I am sure it will be adapted some more. I am however looking for opinions and advice.

http://www.jaystebbins.com/movies/Boattest.mov

Chris I put this in the clip sub forum already...

[Chris Hurd]

That's from an XL H1 preset submitted by our own John Benton at http://www.dvinfo.net/conf/showpost....8&postcount=52 -- there appear to be two versions of it and I don't know why I never got around to updating the XL H1 download library with those two submissions. I'll try to get that updated today, along with the XH versions. Thanks for pointing them out!

[Floris van Eck]

Have the custom presets in the sticky section been updated to reflect the XL versions more accurately or are they the conversions that were made in the very beginning?