Auto exposure algorithm for shooting - auto iso, ae (autoexpo.mo)

Started by pravdomil, July 20, 2013, 10:19:10 AM

Previous topic - Next topic

0 Members and 1 Guest are viewing this topic.

RenatoPhoto

Quote from: pravdomil on September 15, 2013, 06:32:26 PM
well could you try press shutter half way and remember what values it set, and goto the autoexpo menu and compare with values at the cyan linem, does it match?
Yes it matches.

Now I see that the ISO curve can be displaced up or down and also the same can be done to the AV curve.  So by manipulating these curves I can bring the the shutter curve so that the shutter speed coincides with the brightness value at a lower setting.

I will analyze these curves to better understand how to use this algorithm.

Thanks
http://www.pululahuahostal.com  |  EF 300 f/4, EF 100-400 L, EF 180 L, EF-S 10-22, Samyang 14mm, Sigma 28mm EX DG, Sigma 8mm 1:3.5 EX DG, EF 50mm 1:1.8 II, EF 1.4X II, Kenko C-AF 2X

pravdomil

Quote from: RenatoPhoto on September 15, 2013, 06:55:39 PM
I will analyze these curves to better understand how to use this algorithm.
well now autoexpo is little complicated, this is a prototype, it will be simplified soon I hope

dsManning

Love the work on this.  Some really incredible results.  I had a thought while testing Auto Exposure for a few minutes during a wedding I shot this past Saturday.

Would it be possible to program one of the 'lesser used' buttons (by my day to day use at least) like the DoF preview button, to quickly set 1 out of 3 (Shutter, Fstop, ISO) and have the other two variables 'auto expose' using the same projected graph, based off the 1 constant you set?

I'm sorry if that is confusing.  Best in camera scenario;

Settings are 1/125th shutter, 2.8-11 fstop, 100-800 ISO

Great for outdoors shadow to highlights.  Say for one shot I want to quickly take, I want to shoot as close as I can to f2.8.  My above convoluted question quickly summed up is, would it be possible to press the DoF preview button after you set fstop to 2.8 and have the auto exposure module recognize this and expose with a shallow DoF?

Thanks in advance.

Doyle4

Hi there,

Been asked to post here as Autoexposure hasnt worked on 600D for awhile now, last time it worked was on TragicLantern NewMem, everynightly build i have tried it still dosnt, iv add the module from NewMem for 600D and the module is too old, any ideas?

When the module is loaded the shutter/aperture/iso constantly changed, now it does nothing and manual is still active.


a1ex

That table shows what the compiler thinks it's working, not what's actually working ;)

pravdomil

Quote from: dsManning on September 17, 2013, 12:18:28 AM
Would it be possible to program one of the 'lesser used' buttons (by my day to day use at least) like the DoF preview button, to quickly set 1 out of 3 (Shutter, Fstop, ISO) and have the other two variables 'auto expose' using the same projected graph, based off the 1 constant you set?
well this is most requested feature, firstly this has to be implemented: http://www.magiclantern.fm/forum/index.php?topic=7816

Doyle4

Still not functioning properly im afraid,

What happens now is: When loaded aperture is changed to f/16, shutter/iso stays same as when in full manual.
i also noticed when LV was active (AE does not work in LV as far as im aware) my camera screen showed shutter/aperture/iso change everytime i pressed shutter half way for a few seconds, sometimes pressing half way it wouldnt change any settings and overexpose.

pravdomil


Doyle4

ettr disabled, auto iso disabled. nothing, strange one  :-\ could the module be taken from newmem and made to work with latest nightly?

pravdomil


Doyle4


pravdomil


Doyle4


Marsu42

Dear pravdomil,

I had a look at your module again and am actually very near using it for macro shooting ... but I have two requests / enhancements ideas:

1. Add a max. shutter speed option other than the cameras max. speed, for two reasons: a) I then can tie down the shutter speed to ranges where flash works better or to x-sync speeds, b) using the fastest possible shutter makes the shutter break sooner.

2. As it is, I cannot influence autoexpo except through the menu - for live shooting, this is often to slow. Please add options to modify the min. aperture and the min. shutter speed with the wheels on the camera so it allows for more and faster creativity...

... I imagine the dial turns should be easy to detect for the module since you know what you set through autoexpo, and when the user changes aperture/shutter not just reset it to autoexo values like not but also modify min. aperture/shutter at the same time in the direction the user specified.


pravdomil

Quote from: Marsu42 on October 03, 2013, 02:37:48 AM
Add a max. shutter speed
Please add options to modify the min. aperture and the min. shutter speed with the wheels
I know I know, It's in TODO list. You can make pull request to autoexpo repo.

Marsu42

Quote from: pravdomil on October 03, 2013, 02:35:06 PM
I know I know, It's in TODO list.

Sorry, I didn't want to pressure you, I didn't know that's what you meant by "wheel shortcuts" in your todo list. Feel free to add "max. shutter speed" to it though, you can really customize just about everything in the module, only this (for me) important setting is missing.

djronbxs

should this be disabled when taking bracketed hdr photos ? also are there any best settings for the Canon 550D camera ?

thanks

pravdomil

Quote from: djronbxs on October 10, 2013, 06:31:17 PM
should this be disabled when taking bracketed hdr photos ?
these conflict is not yet handled, planned
Quote from: djronbxs on October 10, 2013, 06:31:17 PM
also are there any best settings for the Canon 550D camera ?
sorry don't have 550D

vertigopix

Hello pravdomil,

Can you tell me if i can use your module with a manual lens (Zenit Helios 44-2) ?
I have tried but bad results... (under exposure)

Maybe it's not done for this usage...  :-[

Thanks a lot !

pravdomil

it should work with manual lenses (with and without chip), but I didn't test it much

ShootingStars

Hi, I've been testing this... from my understanding...

THIS - Aims for fastest shutter possible by going to the lowest aperture and highest iso set. More for street/event photography.
AETTR - Aims for lowest noise possible by exposing for the brightest highlights, aims for lowest iso. More for landscape?

Sorry I am fairly new to auto expo.

pravdomil

this aims for user define exposure curve for each BV value of scene

vertigopix

when I have time, I will experiment with a manual lens.
I hope this week !

But the question is what to configure for the aperture ?