Menu

Show posts

This section allows you to view all posts made by this member. Note that you can only see posts made in areas you currently have access to.

Show posts Menu

Messages - c2s07

#1
Feature Requests / Re: Auto contrast adjustment for H.264
February 02, 2019, 08:37:32 PM
Well, ALO can increase the contrast somewhat, but it's not going to maximize the output range like how "auto levels" in Photoshop works, which is essentially what I'm currently doing in postprocessing.* Furthermore, ALO cannot seem to be enabled in M-mode or when Highlight Tone Priority is active, both of which I use.

* By the way, there is a difference between increasing contrast by modifying the tone curve, and by stretching the levels; I think the latter should be tried first, though in some cases it shouldn't be taken to the extreme.
#2
Feature Requests / Re: Auto contrast adjustment for H.264
February 02, 2019, 12:28:34 PM
Yes, I think you understood the question: maximizing scene-dependent contrast. It's the varying lighting conditions that pose the problem. During continuous video recording, I can't fix and maximize the contrast for some low-contrast scene such as when the sun is behind my back, because if I turned the camera to face the sun, a lot of shadow/highlight details would then be lost to clipping.

So in this sense, the static picture style contrast is a bit inpractical. Instead, it would have to be adaptive; evaluated for each video frame*, auto-adjusting itself in very fine steps (so that the viewer doesn't see when the value is changed) in order to maximize contrast without causing clipping. But now I seem to recall some discussions on these forums, stating that ML cannot have very fine control over the picture style settings and the internal values they use?

* The ML histogram seems to be already making the statistical calculations to find out how severely the highlights are clipped, so at least the calculations shouldn't be too heavy.
#3
Feature Requests / Auto contrast adjustment for H.264
February 01, 2019, 06:39:40 PM
Here is what I would like to be able to do in ML.

I tend to record videos with minimal contrast in picture style, HTP enabled, and enhancing contrast by stretching levels in post-processing* on the compressed data. But as the compressed data is only 8 bits in bit depth, I've been wondering if it would be possible to do this in-camera, just after picture style is applied. If I recall correctly, the bit depth is still 10 bits / channel at this point. I have some programming experience, but my educated guess would be that this sort of thing is undoable in ML even if I had all the programming experience in the world?

I know we can write LUA scripts, but my understanding is that the scripts can only operate the camera when it is in an 'idle' state, by which I mean that the camera is not currently exposing a still frame, or recording a video clip.

Otherwise, if possible within reason, I'd be interested in looking into this...

* (Avisynth scripting)
#4
Hopefully you don't mind the bump, but I'm interested in hearing whether it would be possible to fix this persisting problem with today's knowledge and experience. I just tried it with the most recent build, and it's still present.

Would you like me to post a video of me operating the camera, where I enable FPS override and adjust the related settings, all the while filming the camera's LCD screen and the button panel? This way, ML developers without 6D could see what the problem looks like exactly.
#5
I knew I recalled some talk about a hotkeys module on these forums... it's been almost exactly a year, too.

Although I haven't been watching these forums too closely during the last several months, I don't think I've spotted any finished modules or other updates allowing custom hotkey assignments to any ML function. As I'm still interested in this, I'd be grateful to hear if there's been any progress.
#6
I would call this "75% manual mode": you decide Av, Tv, and EC, the camera decides ISO. :-)

It would be useful in movie mode as well. For example, on 6D, my current options seem to be:

A) Full manual exposure: you decide Av, Tv, and ISO, the camera decides nothing.
B) Manual exposure with auto ISO: you decide Av, Tv, and set auto ISO, but since there is no EC setting to adjust (for auto ISO), the exposure is fixed at zero EC
C) Automatic exposure: you decide Av (assuming manual aperture lens), EC, and auto ISO is always active, but you have no control over Tv.

Tv priority movie mode unfortunately does not exist. If it did, it would be a workaround for me and other manual aperture lens users, as you could set Av on the lens, Tv and EC on the camera, and then activate auto ISO and let the camera take care of the exposure based on your chosen EC setting.

Canon could have just made the A, P, Av, Tv, and M modes work in movie mode just like they do when shooting still images (in terms of exposure related settings).
#7
Currently this can be done by opening the ML menu, and going to white balance advanced settings. It's not really convenient though, it could use some kind of shortcut key combo. The partially opaque ML menu stays in front as well, making it harder to judge the correct WB.
#8
The intervalometer is already able to capture silent pictures, just enable both and it works. :-)

The large delay between the shots, if not reduced, is going to be a little problematic for timelapses, as it will result in rather high real-time multipliers in the finished videos. For example, 1 frame / 20s = real-time x 480 @ 24 fps.
#9
Hello,

I did a search on this, but it seems this specific case isn't discussed yet.

I've just tried silent pictures for the first time, hoping to replace FPS override for timelapses. With the latter, I've been able to use the LV power save options, but with silent pictures + intervalometer, the power saving doesn't seem to work. I've tried both "Standby" and "While recording" in its options, but the display wakes up every time the camera captures an image (yes, these are not movies). With less than 5 seconds between an image, the display is on about half of the time or so. By the way, do you think it becomes harmful for the screen over time, if the display toggles on and off this way, for extended periods of time?

I also tried disabling image review in Canon menus, but as expected, it didn't affect this in any way.

If the LV power save function cannot be active for 100% of the time (like with FPS override), fortunately I can get closer to it by minimizing the screen brightness... and perhaps by disabling the global draw as well.

Anything I've missed perhaps?
#10
Heh, so we almost got ourselves a complete GND filter effect in ML, after all. If only the strength of the effect and the start/end points were adjustable. :-)

#11
And if you're using Avisynth, you can try DePanStabilize ( http://avisynth.org.ru/depan/depan.html ).
#12
For finding the threshold, I was thinking of suggesting a new histogram option for showing the brightest level present, but I noticed that the spotmeter set to percent unit seems to work well for that purpose. And it's correct that things like contrast in picture styles should be decided first before setting the threshold in zebras settings.

Also, I just noticed I created this thread in wrong subforum; "general discussion / general chat" instead of "using Magic Lantern / general help Q&A". Feel free to move it if you wish.
#13
Hello,

First of all, this thread is not about shooting RAW video (so any thoughts related to RAW video shooting may not apply).

When you use negative values for ML digital ISO, the clipped highlights of course get clamped more as you lower the value. I understand that it's how it works, as ML digital ISO doesn't make truly lower analog ISOs, no problem with that.

However, this reduces the effectiviness of the zebras overlay. If you're using 100%/255 for the overexposure limit (for maximum precision), zebras won't display after the effect of negative ML digital ISO is applied. That's because the clipped highlights are now clamped, and since no pixel will ever be able to reach 100% brightness, zebras will not trigger.

I can always lower the zebras overexposure threshold in relation with negative ML ISO; doing this won't make the zebras 100% accurate, but at least you can see them again.

Is there anything else that can be done, or perhaps looked forward to in the future versions?
#14
In M-mode? When using manual lenses, the Av-mode should give you the most accurate preview.
#15
Hmm... if it really was as dark as the beginning of the video suggests, wouldn't the fire contribute much more to the lighting of the scene, even if it's partially enclosed?

Maybe an ND filter was used here?

#16
Hello,

While recording a video with "HDR video" enabled, the LV display alternates between the low and high ISO exposures, for about 3 seconds each. I was wondering if this an intentional choice by the devs and possibly customizable, or simply an unavoidable behaviour.

As an example, if you're trying to expose to the right in a scene where the lighting often changes significantly (or perhaps your subject moved between the camera and the sun just when the high ISO display kicked in), you might not want to wait for the three seconds it takes until the lower ISO is displayed again. For cases like these, blocking the high ISO display entirely (while recording) would be useful.
#17
I hope you didn't abandon the thought of uploading your hot_keys module yet; I'd still like to take a look at the code, as you made it sound like it might be very close to one of the changes I've been thinking of. I've been reading the code of other modules around here, and it seems it might actually be possible for me to learn to at least edit an existing module, given it's close enough to what I'm aiming for as well. :-)

I know I said I'm not a strong programmer, but I understand the basic logic, and could notice some similarities to what I've dabbled with before.
#18
Thanks to everyone so far. :-)

I wouldn't call myself a strong programmer, and I have no experience in C. But I do have some experience in programming, and in fact posting a sample module for me to look at sounds like a good idea, as I've often learned by some taking time to analyze and edit an existing bit of code. At least it's worth a try.

I'll take a look at dmilligan's list while waiting for Marsu42's upload, heh.
#19
Hello,

How long would it take for a complete beginner to learn modules writing, and what programs would I need? I'm a bit curious about this as I like customizing things, and since my preferences sometimes differ from those of others, custom modules for personal use might be the way to go for me. If it takes at least months to learn this, then it's probably not worth the time for me, as the changes I've been thinking of are relatively simple.

I can give you a few examples, and if things like these cannot even be achieved with modules (or scripts), let me know.

1) I'd like to try to re-assign some of the camera buttons to toggle ML features. For example, the top LCD panel light button (or some other button) could quickly toggle the "LV DIGIC peaking / Edge image" effect instead. Can something like this be achieved with modules?

2) Suppose I wanted to customize the arrow/set shortcut pairs to my preferences. For example, the horizontal arrows would control the basic color temperature (K) value, and the vertical arrows would control the green/magenta shift. And while at it, perhaps the SET-button could toggle the "LV crazy colors / extreme chroma" effect. Can something like this be achieved with modules?
#20
General Help Q&A / Re: Extreme chroma with picture style?
November 29, 2013, 08:52:12 PM
I know, but I wonder if the devs want yet another thread dedicated to "I have a custom shortcut button idea!", at least not until such things are properly doable (which they aren't yet, from what I've understood). :)

So I was thinking it would best to just mention these here for now, and if it becomes possible to assign any feature to any custom button, I'll make a proper feature request later on.
#21
General Help Q&A / Extreme chroma with picture style?
November 28, 2013, 05:50:30 PM
Hello,

I like using Magic Lantern's "extreme chroma" effect for perfecting the white balance. While waiting for a stable version for 6D, I thought I would try creating a similar effect via a custom picture style:

- Landscape style as base
- Maxed global saturation (+4)
- Maxed individual color saturations in picture style editor (2nd tab, R/Y/G/C/B/M)

It's ok, but not quite there yet. I wonder if that is all I can do with the original software?

I also have related feature requests for 6D ML, might as well mention them here.

1) There are several buttons on 6D which are unused in movie mode. If/when possible to assign custom shortcuts, it would be convenient to have the extreme chroma effect toggleable/holdable from a custom button.

2) I wasn't surprised at all to find out that it's not possible to adjust white balance while recording. Perhaps the multi-controller could be utilised here. It's already controlling the white rectangle position, but with an extra button press, a white balance adjustment mode could be toggled:
2a) left/right = Kelvin value
2b) up/down = green/magenta shift
2c) optional: when active, automatically toggle extreme chroma effect as well (replaces feature request #1)

Thanks for reading, and for any thoughts. :)
#22
General Development / Re: Fast Advanced Bracket
October 14, 2013, 09:37:05 PM
That cannot work... it's not duct tape! :)
#23
The spaceship called "Earth"... or a humongous carousel, take your pick. :)
#24
Bump! Sorry, but this is an interesting topic. I've been testing settings on 6D, to see what has changed over the years.

So regarding movie shooting and highlight tone priority, on 6D:

For some reason, HTP seems to only go up to 6400 analog ISO and not higher (at which point the ISO reads 12800 D+). Don't ask me why this limitation. So comparing 12800 D+ to true 12800, using static movie clips shot in a relatively dark corridor: 12800 D+ has shadows with a greenish tint, while the true 12800 has shadows with more accurate colors.

If you're shooting a video in darkness and need a way to brighten up the footage in-camera, this limitation makes HTP inferior to actually using true ISO 12800 or the 25600/H. On top of the latter two, you could try using auto lighting optimizer (a subtle effect), or a custom picture style that attempts to replicate the effect of HTP by lifting tones (caveat: this picture style won't be operating on 14 bits).

Another observation is that 6D won't let you use (true) ISO 25600 in movie mode. Considering that 6D specifications, to my understanding, suggest native ISOs from 100 to 25600, I have no idea why this true ISO 25600 is then blocked in movie shooting, as one would think it's always a better option than 12800 digitally pushed. But I guess this has been the case since 500D.

Feel free to post your thoughts, and correct me where I'm wrong. :)
#25
General Development / Re: Fast Advanced Bracket
September 28, 2013, 01:01:18 PM
I was hoping the tweak eliminated the mirror slap between exposures. :)