DCamProf - a new camera profiling tool

[howardm]

I'll try to get a 0.9.11 MacOSX static build out tonight (after parent/teacher conference  )

Do people find the MacOSX build useful or am I wasting  my time?

[torger]

I'll try to get a 0.9.11 MacOSX static build out tonight (after parent/teacher conference  )

Do people find the MacOSX build useful or am I wasting  my time?

I think a download counter would be more reliable than getting replies in this thread, I've now put up a link to this thread from my web page, but I guess most people that downloads won't be members in the forum, they just read, find the link and download.

I will go for a vacation over the weekend now so there won't be any 0.9.12 for at least a few days at least

[howardm]

Oh, I suppose.

But that would require effort 

It'd be nice if box.com made that available w/o spending $45/month which aint gonna happen.

Maybe some other method.  Anyone got a suggestion?

[AlterEgo]

It'd be nice if box.com made that available w/o spending $45/month which aint gonna happen.

why do you need to pay ? this is not a gigabyte traffic... I keep builds in my free box.net/box.com account... you do not have thousands of people downloading it... I think the most ever downloads for my build was ~25 recently... a lot of people will build themselves... so just use a free account... and free account has some counter where you can see how many times somebody downloaded or at least attempted to download the file

[howardm]

I didn't see any free option for download counting or stats.  It wanted a business plan upgrade at $15/month x 3

Anyway, I signed up for bitly.com which does what I need and future links will (assuming I remember) be bitly.

[AlterEgo]

I didn't see any free option for download counting or stats.  It wanted a business plan upgrade at $15/month x 3

Anyway, I signed up for bitly.com which does what I need and future links will (assuming I remember) be bitly.

there are no special options, it is just there in a simple form, w/o any details - see the simple counter ? "3 downloads or attempts"

[howardm]

Thanks much, I had not noticed that and I do wish web designers would stop with the 'light grey text on white' meme.  Usability sacrificed on the alter of trendiness.

Apparently 6 brave souls have downloaded 0.9.7

[torger]

I have about 50 downloads of the 0.9.7 source archive. It should have spanned only one week, but due to the bugs in 0.9.8 - 0.9.10 it got some more downloads. The page itself got 650 views the first 15 days of September, and the tutorial about 450 in the same period. So nothing massive, but a noticeable interest. The interest seems to be rising after the tutorial was published.

When searching on "camera profiling" on Google (using incognito page to not get personalized result) the dcamprof page is still as far back as page four. I hope and think it will rise as time goes by, as there really isn't much software out there in this genre. DCamProf can do things no commercially available software can do. It's command line though, but Argyll is too and it does pretty well so I think DCamProf will find its users sooner or later . Meanwhile it's nice to have some brave early adopters.

[Frederic_H]

Seeing hue shifts in skies that weren't so obvious previously, despite a very relaxed LUT.
Will investigate tonight...

[Alan Goldhammer]

DCamProf can do things no commercially available software can do. It's command line though, but Argyll is too and it does pretty well so I think DCamProf will find its users sooner or later . Meanwhile it's nice to have some brave early adopters.

I for one am following this with a great deal of interest.  I'm waiting until a few more of the issues have been sorted out and the weather turns a little colder (the best time for sitting at ones work station running various programs).  I don't mind command line as I've been using Argyll for some years now.  Keep up the good work here!!  I've been reading through the tutorial.

[torger]

Seeing hue shifts in skies that weren't so obvious previously, despite a very relaxed LUT.
Will investigate tonight...

Bad LUT bends are not manifested like this (smooth hue shifts), if you would have that you see things more similar to posterizing. It's quite difficult to make bad LUT bends visible in real images as one have to have a gradient that exactly hits the area of the bad bend. That's why I think plot analysis is an important tool when doing more advanced design otherwise those bad bends are easily missed.

We've had a recent history of troubles in the highlights, rolling off towards clipping is a quite difficult problem, so there can be yet a problem there. First thing would then be to disable the curve we've had issues with by setting KeepFactor to 1.0 (default 0.0) in the Curve section. In the neighbor "dummies" thread there was an issue with magenta cast close to clipping (which does not happen in the latest 0.9.11), but the magenta here seems too far off from clipping to be related to that.

However skies can go from cyan to magenta for real, a bit depending on where the sun is and atmospheric conditions. DCamProf keeps saturation closer to clipping than typical bundled profiles so it may have just made a real sky hue shift more visible.

If it's not there at all with the bundled profile, then it's probably a problem. If it's just more visible it's probably not a bug, but it may be an undesirable look to you. Then letting it desaturate more can be an option. You can then reconfigure the tone reproduction rolloff to this for example:

    "Rolloff": {
        "KeepFactorHueCurve": { "CurveType": "Linear", "CurveHandles": [ [ 0,0.0 ], [ 360,0.0 ] ] },
        "LowSatScaleHueCurve": { "CurveType": "Linear", "CurveHandles": [ [ 0,1.0 ], [ 360,1.0 ] ] },
        "HighSatScaleHueCurve": { "CurveType": "Linear", "CurveHandles": [ [ 0,1.0 ], [ 360,1.0 ] ] }
    }

(read data-examples/ntro_conf.json for an explanation of the parameters)

Another more advanced configuration would be to use the stretch operator to even out light blue sky colors, like you can even out skin color.

When it comes to these type of color issues, if there is a bug it's most likely related to the tone reproduction operator, so what one can do is to render a linear profile (no tone curve) and have that as a reference to compare with. If the color shift is not there with the linear profile it is a problem. One can of course also compare to the bundled profile and I would do that as well, but then keep in mind that there's a (minor) risk that they have already done things like smoothing out colors.

[torger]

I for one am following this with a great deal of interest.  I'm waiting until a few more of the issues have been sorted out and the weather turns a little colder (the best time for sitting at ones work station running various programs).  I don't mind command line as I've been using Argyll for some years now.  Keep up the good work here!!  I've been reading through the tutorial.

Thanks for the interest. When I think it's stable enough for a wider audience, probably meaning that it's been out for a while and used for some period with no needs to update, there'll be a release of version 1.0.0. Hopefully it's quite close

[Frederic_H]

Even with the former curve or the rolloff changes the shift is still there. It looks a bit better in the clouds with the stock profile (attached) though there's some magenta on the right too.
As you can imagine we're close to clipping, and to make matter worse it's an area corrected by an LCC.

I'll check if it's present in the linear profile too. Your suggestion to even out the blue area looks like the way to go.

edit : apparently not relaxed enough according to the table

[torger]

Note that a ICC 3D LUT consists about 50% or so of out of gamut values, values that are not given by the native profile, values that DCamProf just needs to make up from thin air. Normally those values are never displayed as no real color will cause them to appear, but you can force them by extreme white balance settings.

The jaggies on that curve can be such values, ie not really affecting the image quality. I'm thinking about smoothing each curve and may do that at some point, but it's a quite difficult 3D problem (ie you can't really just smooth that curve in isolation as it affects others in 3D) and it's easy to disturb "real" entries which happened in the first attempts.

Making ICC LUTs that look smooth from every angle in a viewer is quite difficult, and it's not contributing to image rendering, which means I've put it on a low priority. The difficulty to make an ICC LUT due to all those out of gamut entries was a problem that took me by surprise. The DNG profile LUT doesn't have this problem as they work with multiplications and additions rather than absolute output values (but that has other drawbacks such that it's not possible to alter the neutral axis).

[torger]

Commenting on the actual image, if I would guess I don't think the magenta cast or cloud edge is an issue due to a bad LUT bend or a bug, I think the color is there in the original, and it's visibility is magnified due to the shape of the tone curve.

If you look at the stock profile's clouds you can see that it's lower contrast than in DCamProf's rendering. Take the cloud fragment in the bottom left corner as an example, in the stock profile it almost disappears into the surrounding sky, while in DCamProf the cloud edges are more visible.

This means that the manually made LUT curve (the one you make with the curve tool and then copy to a JSON file) does not compress the highlights as much as the stock profile. To get a result more similar to the stock profile try compress highlights more in your curve. This will lower cloud contrast and desaturate the colors, so the "cast" (which I think is a natural sky variation) will be less visible and the clouds will also look more uniform.

(For readers unfamiliar with this manual curve -- this is a special step required by Capture One only. It may be possible to extract it from the LUT and by that copy the stock profile's curve, say by probing the neutral axis, but so far one have to design it manually and I don't think it's that bad as curve design is a matter of personal taste too, the stock curve is not necessarily the best.)

[howardm]

v0.9.11 Mac OSX binary is up...........

https://app.box.com/s/4y3kq5laepy1yp18i69t006jt9zpv0bd

Interestingly, the OSX binary is only 6.3MB (and static) whereas the Windows one is 14.

[Alexey.Danilchenko]

Oh, I suppose.

But that would require effort 

It'd be nice if box.com made that available w/o spending $45/month which aint gonna happen.

Maybe some other method.  Anyone got a suggestion?

Google Drive - does not cost a penny

[howardm]

Thanks but the only reason I mentioned that was that box.com didn't *seem* to offer a simple (read: free tier) download counter but that was only because when I looked, no one had d/l'd it yet.

[AlterEgo]

Interestingly, the OSX binary is only 6.3MB (and static) whereas the Windows one is 14.

it is not... I include 3 versions of manual and tutorial as standalone self contained files... otherwise it is ~8MB + ~100Kb OMP .dll

[Frederic_H]

Commenting on the actual image, if I would guess I don't think the magenta cast or cloud edge is an issue due to a bad LUT bend or a bug, I think the color is there in the original, and it's visibility is magnified due to the shape of the tone curve.

If you look at the stock profile's clouds you can see that it's lower contrast than in DCamProf's rendering. Take the cloud fragment in the bottom left corner as an example, in the stock profile it almost disappears into the surrounding sky, while in DCamProf the cloud edges are more visible.

This means that the manually made LUT curve (the one you make with the curve tool and then copy to a JSON file) does not compress the highlights as much as the stock profile. To get a result more similar to the stock profile try compress highlights more in your curve. This will lower cloud contrast and desaturate the colors, so the "cast" (which I think is a natural sky variation) will be less visible and the clouds will also look more uniform.

(For readers unfamiliar with this manual curve -- this is a special step required by Capture One only. It may be possible to extract it from the LUT and by that copy the stock profile's curve, say by probing the neutral axis, but so far one have to design it manually and I don't think it's that bad as curve design is a matter of personal taste too, the stock curve is not necessarily the best.)

It's there in the prelim profile too (no additional curve) and you're right more highlight compression certainly helps to fade it. However the effect is visible in darker areas such as the sky too. I could try to even out the tones there I suppose.