Advanced Bracket Features Request

[NickZee]

Thank you nightly builders for the new advanced bracket updates! 

I particularly appreciate the increase in frames from 9 to 15!  Thank you!

I would like to request these updates. 

1.  Add 0.3 and 0.7 EV increment options.

2.  Shutter speed sequence calculator.  In the Promote Control, when you select your shutter speed and EV increment, it calculates the shutter speed range based on the number of frames you select.   The good thing about this is that you get an on screen visualization of the shutter speed sequence (under to over) based on EV and Frames.   See this for an on screen example, http://youtu.be/TstWu67pKj0?t=5m2s  (5:02 to 5:40)

3. Add more Frame from 15 to 40. (just in case you need them  )

4. Faster between shots.  Especially in Autodetect mode.

Thank you again!

[Greg]

2.  Shutter speed sequence calculator.  In the Promote Control, when you select your shutter speed and EV increment, it calculates the shutter speed range based on the number of frames you select.   The good thing about this is that you get an on screen visualization of the shutter speed sequence (under to over) based on EV and Frames.   See this for an on screen example, http://youtu.be/TstWu67pKj0?t=5m2s  (5:02 to 5:40)

Interesting idea.

3. Add more Frame from 15 to 40. (just in case you need them  )

I never needed more than 9x2EV on 500D. We can change it to 20, that looks nice in the ML menu. 

4. Faster between shots.  Especially in Autodetect mode.

Autodetect mode can not be faster. ML must be checked after each shot its parameters.

On the 500D is a fast bracketing - http://www.magiclantern.fm/forum/index.php?topic=8535.0
He is working at full speed continuous mode.

[Greg]

[boogotti84]

Yes pls! for 6D, this will be very helpful! will happily donate £15 / thats $24 for US people to the developer for this function on the 6D
compiled as i can't program

-15 frames upped to 40
yes i need more for creating hdri's for VFX CGI work

- Add 0.3 and 0.7 EV increment options, (more lower EV possible?)

- Shutter speed sequence calculator

- Faster between shots i.e mirror lock up limit mirror vibration, faster shots, continuous shooting?

[Greg]

-15 frames upped to 40
yes i need more for creating hdri's for VFX CGI work

If there are more people who need this function, I do it.
Done - https://bitbucket.org/hudson/magic-lantern/pull-request/293/feature_hdr_bracketing-15-frames-upped-to/diff

- Add 0.3 and 0.7 EV increment options, (more lower EV possible?)

Yes, it is possible.

- Shutter speed sequence calculator

It need a few corrections.

- Faster between shots i.e mirror lock up limit mirror vibration, faster shots, continuous shooting?

I do not have 6D, I do not know how to do it.
Fast bracketing only work on 500D.

[boogotti84]

If there are more people who need this function, I do it.
Done - https://bitbucket.org/hudson/magic-lantern/pull-request/293/feature_hdr_bracketing-15-frames-upped-to/diff
Yes, it is possible.
It need a few corrections.
I do not have 6D, I do not know how to do it.
Fast bracketing only work on 500D.

Thank you greg, is this build on the 6D, 1% Nov build?
http://www.magiclantern.fm/forum/index.php?topic=3904.2775

do you reckon you can get the 0.3 and 0.7 EV increment options? in a build?

Also - Shutter speed sequence calculator

happy to pay you if you can get these two in pls

thanks again

[Marsu42]

If there are more people who need this function, I do it.
Done - https://bitbucket.org/hudson/magic-lantern/pull-request/293/feature_hdr_bracketing-15-frames-upped-to/diff

Good thing alex isn't here right now, he'd get a heart attack - "When the cat's away the mice will play" :-p

- Add 0.3 and 0.7 EV increment options, (more lower EV possible?)

There is a reason for this not being implemented, just like the 15 frame limit (which was raised from 10 after a very lengthy discussion) - it doesn't make sense, or no one could come up with a scenario in which it would. The raw files are so elastic you can easily +-1ev postprocess the exposure, so a too small spacing only is a shutter killer.

Yes pls! for 6D, this will be very helpful! will happily donate £15 / thats $24 for US people to the developer for this function on the 6D

On a final note: I think it's great people supporting ML (donate to the EFF!), but I'd still favor consistency and common sense when coding over someone waving with some dollar bills. Maybe it would be better to do a private binary "code on demand" build for this request and cash in than to do a pull request for all ml users.

[Greg]

Also I think it is not useful.
Maybe I should do the Advanced menu, as is the FPS override?

[Marsu42]

Maybe I should do the Advanced menu, as is the FPS override?

Hmm, looking at the bracketing menu there doesn't seem to be anything to esoteric that it needs to be hidden, also the menu is very small (unlike the fps override). What do you have in mind?

Note that there currently are two problems with the "advanced menu" design:
* it says something about "for experts" and "use with care" which isn't the case if the options are just hidden to avoid clutter
* when you change an "advanced" option it isn't hidden anymore but moves to the "non-advanced" default menu which can create confusion if the changed menu item was part of a logical group that is now torn apart.

[Greg]

I thought about something like this:

if(advanced)
{
    frames (auto - 40)
    fast bracketing
}
else
{
    frames (auto - 9)
}

Is there any difference in image quality between the bracket 4x2EV vs 16x0.5EV?
I always use 2EV.

[Audionut]

Is there any difference in image quality between the bracket 4x2EV vs 16x0.5EV?
I always use 2EV.

Personally I find midtones (-4EV below sensor saturation) to retain sufficient quality.  So I would use 2x4 in your scenario.

CGI guys are always saying different though!

[Greg]

Personally I find midtones (-4EV below sensor saturation) to retain sufficient quality.  So I would use 2x4 in your scenario.

CGI guys are always saying different though!

The 500D when using bracketing 3EV or more, receive poorer quality.
I've never met a scene which requires more than 9x2EV the 500D. So if anyone needs the best picture quality should be enough 18x1EV. A larger number of frames does not make sense.

We have to decide what to do, what to change.

[engardeknave]

How about fixing this issue? I have been lobbying to get this fixed forever.

https://bitbucket.org/hudson/magic-lantern/issue/1661/bracket-in-c-mode-5d2

It seems like other people are having similar or related problems:

https://bitbucket.org/hudson/magic-lantern/issue/1665/hdr-bracket-in-c-mode-when-setting-manual
https://bitbucket.org/hudson/magic-lantern/issue/1691/turning-off-bulb-mode-when-shoot-bulb-mode

[engardeknave]

How about automatically putting each bracket set in its own folder? I would kill for this.

Fast bracketing on the 5D2 as well.

[Audionut]

I agree with what Marsu42 has said.

I don't see any reason why there needs to be 1/3rd stop resolution and you've already added increased frames.

[boogotti84]

Hey Guys hdri's are used for Global Illumination/reflections, these extra stops make a difference, depending on how much of dynamic range your trying to capture. You cant just say that 7 exposures will cover all situations. It depends on the environment what range your trying to capture.

I understand for the average user that 7 exposures will cover all the bases for just image use.
But for the niche VFX artist user, Can make use of these extra exposures. As we are looking to capture dynamic resolution more stops the more resolution. Yes raws you can push and pull them a stop or two. But this is emulated. Yes you can recreate it but your dynamic range will be noisey and less in dynamic range resolution.

I know for the masses using hdris that over 7 exposures is excessive. But for us vfx guys is much needed for accurately capturing the most dynamic range resolution for rendering in cgi.

Spheron HDR Camera
This is used by studios has 26-f stop range in the hdri image. Used for CGI re-lighting
http://www.youtube.com/watch?v=4keIdSE6aZ0
Hdri dome light
http://www.peterguthrie.net/blog/2010/04/vraysun-and-hdri-sky-tutorial/

Greg, i can send you the money by paypal? i'll pm you my email? can you pls work on these features for 6D?
- Add 0.3 and 0.7 EV increment options,
- Shutter speed sequence calculator

[Greg]

I do not want money for my work on ML. A new SD card would be really helpful for me, maybe I can get one for Christmas

I think the main repository we can add a function Shutter speed sequence calculator.

This we need to create another repository :
-15 frames upped to 40,
- Add 0.3 and 0.7 EV,

[boogotti84]

I do not want money for my work on ML. A new SD card would be really helpful for me, maybe I can get one for Christmas

I think the main repository we can add a function Shutter speed sequence calculator.

This we need to create another repository :
-15 frames upped to 40,
- Add 0.3 and 0.7 EV,

Hey Greg its coolio  you can buy an SD card with it, i have no idea, how to program and compile this together, if you or someone can get these features as requested into a compiled 6D build the im more that happy to pay for it... for the time and effort.

[Greg]

My idea:

In the main repository:
- Reduce the amount of frames from 15 to 12 (12x2EV = 24EV this is good)
- Add calculator

If you need more frames change
ML -> settings -> magic.cfg "hdr.frames = 6", enter the value that you need
This method of working, I checked it today.

[NickZee]

But for the niche VFX artist user, Can make use of these extra exposures. As we are looking to capture dynamic resolution more stops the more resolution. Yes raws you can push and pull them a stop or two. But this is emulated. Yes you can recreate it but your dynamic range will be noisey and less in dynamic range resolution.

First off, thank you for the great response to these requests!  Amazing!

I want to reiterate boogotti84 about the benefit for smaller EV increments.  I shoot interiors and the range from the shadows inside a room to the sun outside the windows is so great that without these smaller steps we lose some of the quality/data.  I'm being schooled by the gentleman at http://digitalcoastimage.com/portfolio/content/01_large.html and he recommends the 1/3 or 2/3 stop with 15 to 18 frames (less or more depending on scenario obviously) to capture the data properly.


Thank you again!

[dmilligan]

If you're going to be taking that many pics anyway, maybe consider using the intervalometer instead of advanced bracket. I have a module that can ramp any exposure setting during an intervalometer sequence:
http://www.magiclantern.fm/forum/index.php?topic=8431.0

You can also now trigger the intervalometer to start based on a shutter press, so once you set it up, it would work just like advanced bracket.


You know I've seen this requested by CGI artists several times to have rediculous numbers of frames and small EV increments, and I wonder if it's not simply the stacking of multiple frames that is giving you the good results. I'm an astrophotographer and we use stacking in this manner to reduce noise and increase dynamic range.

In other words, I wonder if this exposure sequence:
-6, -5.5, -5, -4.5, -4, -3.5, -3, -2.5 - 2, - 1.5, -1, -0.5, 0, 0.5, 1, 1.5, 2, 2.5, 3, 3.5, 4, 4.5, 5, 5.5, 6
is the same as:
-6, -6, -6, -6, -4, -4, -4, -4, -2, -2, -2, -2, 0, 0, 0, 0, 2, 2, 2, 2, 4, 4, 4, 4, 6, 6, 6, 6

I think it probably is.

[dmilligan]

Also wonder if dithering would help you guys, if you do that (for wide angles you'd probably need the shift function of a tilt shift lens to do that properly). Here's an example I think you could achieve equal, if not better results with the current 'limited' capabilities of ML:

Rather than 20 exposures with 0.5 EV increments, shoot 4 sequences of 5 exposures with 2EV increments and move the camera a tiny bit (or shift your fancy tilt shift, if you've got one) to dither inbetween each group. Of course you'll need to align them in post, but there's plenty of software to do that automatically.

[Marsu42]

I want to reiterate boogotti84 about the benefit for smaller EV increments.  I shoot interiors and the range from the shadows inside a room to the sun outside the windows is so great that without these smaller steps we lose some of the quality/data.

I really, really doubt that until proven wrong:

If you shoot with 1ev spacing (there's not even the 10 exposure limit if you set it to auto) and then +-1/3ev these in postprocessing, you're getting your 1/3, 2/3, ... steps, and considering these are 14bit raw files with a lot of potential for shadow and highlight recovery there should be no quality loss at all.

[Greg]

Shutter speed calculator sequence seems to be working - https://bitbucket.org/Gr3g01/ml-hdr3/commits/d7eeb042def595b1896ae1f606203c58c024ce31
If anyone has any suggestions on how to optimize this code, I will be grateful.

[engardeknave]

I'm being schooled by the gentleman at http://digitalcoastimage.com/portfolio/content/01_large.html and he recommends the 1/3 or 2/3 stop with 15 to 18 frames (less or more depending on scenario obviously) to capture the data properly.

I just tried a few tests with 10-25 frames and saw no significant difference in the output with Enfuse. But I guess he's using something else. What would that be?