Mirror lock-up trick for handheld shots (poor man IS)

[a1ex]

Idea: http://www.stockholmviews.com/mup/mirror-up.html ("This is especially obvious at shutter speed 1/80s to  1/15s.")
Code: https://bitbucket.org/hudson/magic-lantern/changeset/866be16e840a
Try in tomorrow's nightly build.

Will it work? Worth polishing it?

[ilguercio]

Ok, i just tested it and LV button is awkward to use and it'll prevent normal usage of LV. I have  tried BGMT_PRESS_FULLSHUTTER and it takes 2 pictures, or rather, triggers one normal shot and then another subsequent one where you have to press the sutter again to release the mirror.
SET is clear for me in photo mode (it can be assigned to a function, by menu, but i didn't) . The problem is that i shuold add exceptions here, right?  if (event->param == BGMT_LV && mlu_shake_free && !lv)
so it doesn't get triggered when set is pressed. Uhm, quite a long list, actually...
Quite a problem to assign this function to a button without triggering unwanted pictures but comfortable enough not to spoil the original grip.
Probably not so useful for middle range cameras as they don't recock the mirror in LV. I don't know...

[1%]

Doesn't work in AF for me, just flashes the points, MF is fine. But I'd keep it on if it would work from shutter button. LV button is awkward. Also would be nice to work automatically at shutters under X if set.

I say worth polishing it. The link sold me.

[sutobe]

MF works everytime with the delay time set up in ML menu from locking up the mirror to taking the picture.


with AF enabled sometimes it works.....most of the time it doesn't. I can't reproduce everything that happens.

Pressing LV often just lets the lens focus then stop.

Or focus and MLU but not taking a picture--->only full shutter press makes the camera operable again and takes a pic.

and in 3 of 10 cases it takes a picture.

[a1ex]

Didn't try with AF - the trouble with that is that ML would have to wait until AF is finished.

I'll try to intercept the full shutter; ilguercio's result is promising.

[discocalculi]

Thanks for this!

Looks very interesting. Will try it out!

[engardeknave]

The mirror doesn't go down in liveview though, at least on the 5D2.

[a1ex]

This works quite nice on 5D3, and can set MLU on demand (so the idea of enabling it only for certain shutter speeds is feasible):

Code: [Select]

int mlu_shake_running = 0;
void mlu_shake_task()
{
    msleep(mlu_shake_free * 100);
    SW1(0,0); SW2(0,0);
    call("Release");
    mlu_shake_running = 0;
}

int handle_shutter_events(struct event * event)
{
    if (mlu_shake_free && !lv)
    {
        if (event->param == 0x67 && (MEM(event->obj) == 0x80081 || MEM(event->obj) == 0x800C1) && !mlu_shake_running)
        {
            mlu_shake_running = 1;
            task_create("mlu_pic", 0x1a, 0x1000, mlu_shake_task, 0);
            return 1;
        }
       
        static int mlu_should_be_cleared = 0;
        if (event->param == BGMT_PRESS_HALFSHUTTER)
        {
            if (!get_mlu()) { mlu_should_be_cleared = 1; set_mlu(1); }
        }

        if (event->param == BGMT_UNPRESS_HALFSHUTTER && mlu_should_be_cleared)
        {
            if (get_mlu()) set_mlu(0);
            mlu_should_be_cleared = 0;
        }
    }

    return 1;


[discocalculi]

Tried taking some photos on the fly. It's a bit smoother than the built in Canon feature, but I noticed that sometimes the picture is not taken.

When using a Canon 550D, 0.1 seconds and trap focus, I noticed that sometimes the mirror lock-up would occur, but no picture would be taken until i pressed the shutter.

When changing to 0.2 or even 0.5 seconds the mirror would lock up and a picture was taken and then returned to normal mode without further interaction from the shutter button.

I also noticed that the mirror lock-up would not occur, unless I turned autofocus off from the lens and no picture could be taken, until the autofocus got turned to manual focus on the lens.

[a1ex]

Try latest changeset - on 5D2 and 5D3 it works quite nicely. On the other cameras, it may require tweaking.

[discocalculi]

Thanks. From the few tests I've tried on the new builds, it even works better than the Canon version on the 550D...

[a1ex]

Does Canon has this feature?! or you mean the 2-second self timer?

[discocalculi]

Well, it has mirror lock up. Not very hand-holdable, but...

There are quite a few articles on it. I stumbled on it when I first started shooting with mirror lenses...

5D2, C.Fn III: Autofocus/Drive Mirror lockup 0/1 - Disable or Enable
550D, C.Fn III: Autofocus/Drive Mirror lockup 0/1 - Disable or Enable

Random links:

http://www.cameratechnica.com/2011/04/26/dslr-mirror-lock-up-worth-the-effort-or-not/
http://www.bobatkins.com/photography/tutorials/mlu.html

[a1ex]

Got it - you mean, pressing the shutter twice. ML actually enables Canon's MLU on the fly and automates this.

Would be nice to see some comparisons; at a quick glance, on my 5d3 it seems to have noticeable effect with the 50/1.8 at 1/10 seconds. Not bad.

[discocalculi]

Yes, that's true. Canon requires two presses, which makes ML superior.

Canons model works in an old manner, you press once and decide when to take the picture. I suppose wind , lighting conditions and other stuff might have been the reason for two presses because that way you could measure the scene, and pretty much just wait until the breeze has settled or that "right light" is there/bird in the frame, or whatever...

As long as there's a pause value large enough on ML, it should pretty much everything one can ask for.

Stretching the feature further is probably not possible due the mirror lockup/lack of measure possibilities..

I've just done some quick tests, with a sigma lens that has image stabilisation and without the stabilisation and the MLU feature and somehow got the impression the MLU is better. But needs more testing.

[1%]

Seems to be intercepting perfectly on 600D.

[ilguercio]

As i saw the changeset i took a look at it and as it was pretty simple to change the button i made a few tries. That felt sooo good. I'm going to try the latest changeset, which seems to intercept shutter press and replace it with this feature, when enabled. I'll let you know if it works and if it is useful (i bet so) .

[ilguercio]

Just tried and if i enable all it does is raise the mirror as i press the shutter. I have to press it once more to fire a shot. Something doesn't work.

[1%]

Your camera must be different in that regard. I tried again, works perfectly. Keeping it on

[ilguercio]

Your camera must be different in that regard. I tried again, works perfectly. Keeping it on

As usual with the 50D.
Probably shutter interception doesn't work properly for it?
LED from LV button lights up anyway.

[1%]

Well in modes other than P I sometimes get your problem and the mirror stays locked until you press the button again. So interception isn't QUITE perfect.

[discocalculi]

One thing that bothers me is that the maximum pause is only up to 1 second.

Shooting with long lenses (moon) or macro lenses (extremely small objects), sometimes it can be better to have a pause closer to 4 s, or 10 s to let any camera shake die out. Could it be implemented?

I've also noticed that the feature does not work well with changing shooting mode from one shot/continuous shooting to remote control/2 second remote... Not sure why, but it seems it does not work then...

[discocalculi]

Done some quick tests with a 800mm mirror lens and shooting at a target around some 5 metre away and come to the following conclusion.

No matter what shooting style, live view gave a slight edge of sharpness in my test...

1 ) Photo
2 ) Photo using live view
3 ) 2 second delay
4 ) 2 second delay with live view
5 ) Remote control photo taken
6 ) Remote control photo using live view
7 ) 10 second delay
8 ) 10 second delay with live view
9 ) Mirror lock up (Canon) 2 shutter presses
10 ) Mirror lock up (Canon) live view
11 ) MLU - 1 second delay
12 ) MLU with live view - 1 second delay

The 2, 4, 6, 8 are all sharper than their non live view counterparts.

I perceive the differences between 9 - 10, and 11-12 as somewhat smaller than the differences between other counterparts, this despite contact with the camera in order to activate the functions.

I got the impression that the remote shooting with live view gave the sharpest result, followed by a 2 second delay, and the mirror lock up and all the other live view photos. It's harder to tell which of the ordinary photos that was sharper but I perceived 1 and 9, 11 as quite similar and probably amongst the sharpest ones, most likely due there's not much difference from pressing the shutter one time, or two times (as long as there's long enough pause between the presses).

[sutobe]

tried it with my 550d, I can confirm it not working with Timer mode.

Enabling AutoMLU together with Timer works as usual, so if it's intended that Timer mode is not working with Anti-Shake-MLU, using Timer withAuto MLU still does the trick.

[ilguercio]

One thing that bothers me is that the maximum pause is only up to 1 second.

Shooting with long lenses (moon) or macro lenses (extremely small objects), sometimes it can be better to have a pause closer to 4 s, or 10 s to let any camera shake die out. Could it be implemented?

I've also noticed that the feature does not work well with changing shooting mode from one shot/continuous shooting to remote control/2 second remote... Not sure why, but it seems it does not work then...

There's Canon's proper MLU for that. This is for hand held shooting.