Manual Focus @ Infinity not working

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Re: Manual Focus @ Infinity not working
« Reply #10 on: 28 / October / 2014, 17:00:41 »
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2) MF enabled, set at infinity (SD=65535), pointing at the same subject

S/NL/FL-> INF/INF/INF
DOF/HYP -> inf/1.01 (before halpressing the shutter to get focus); inf/2.87 (after halfpressing the shutter)

Actually I could notice this change in hyperfocal distance because when I activate manual focus the dof calculator frame is always visible, while on the other situation it only showed up only after half-pressing the shutter
Canon A3100IS - 100d
CHDK a3100-100d-1.2.0-3643-full_ALPHA

Re: Manual Focus @ Infinity not working
« Reply #11 on: 28 / October / 2014, 17:02:26 »
And the resulting image from the second shot was out of focus?
Yes, it was, just like the image I show on my first post.
Canon A3100IS - 100d
CHDK a3100-100d-1.2.0-3643-full_ALPHA

Re: Manual Focus @ Infinity not working
« Reply #12 on: 28 / October / 2014, 20:32:38 »
I have a nice little test script that we can try.  I'll have to post it tomorrow - no internet connection from home tonight. 
Ported :   A1200    SD940   G10    Powershot N    G16

Re: Manual Focus @ Infinity not working
« Reply #13 on: 29 / October / 2014, 12:12:43 »
Script posted here :  mftest1.lua

The question this script explores is where the lens mechanical position is when the camera auto focuses versus manually focuses.

To use :
  • Download and install script in CHDK/SCRIPTS folder on your SD card
  • Camera in "P" mode
  • Zoom setting at widest angle
  • Canon continuous autofocus and servo autofocus disabled.  Any face tracking disabled
  • Enter CHDK <ALT> mode and load the script via the Canon script menu
  • Enable Lua Native Calls in the CHDK Miscellaneous menu
  • Point the camera to something off in the distance at infinity ( >20 meters)
  • Start the script by pressing the shutter button
  • Wait while the camera takes three shots - one in auto focus mode, one in AFL mode and one in MF mode
  • Observe the reported SD (subject distance) of each shot on the script console.  Also note the lens mechanical (mecha) position reported on the console
  • Compare the resulting images to determine if they were all focussed at infinity
  • Report results here

The script will allow you to select the focus distance if you want to experiment.  You can also selectively disable the AFL and/or MF options.

It would be useful to let the camera focus on something 6" ( .125 m) away and check the reported mecha position as well.  That gives use the range of the mecha position value.
« Last Edit: 29 / October / 2014, 13:59:14 by waterwingz »
Ported :   A1200    SD940   G10    Powershot N    G16


Re: Manual Focus @ Infinity not working
« Reply #14 on: 29 / October / 2014, 13:44:26 »
    4. Canon continuous autofocus and servo autofocus disabled.  Any face tracking disabled[/li][/list]
    5. Load the script via the Canon script menu[/li][/list]

    4. I don't know how to disable Canon continuous autofocus and servo autofocus. Is it allowed in this model? Ok to disabling face tracking.

    5. Shouldn't I load the script via CHDK ALT mode? How do I load this script outside CHDK?
    Canon A3100IS - 100d
    CHDK a3100-100d-1.2.0-3643-full_ALPHA

    Re: Manual Focus @ Infinity not working
    « Reply #15 on: 29 / October / 2014, 13:58:48 »
    4. I don't know how to disable Canon continuous autofocus and servo autofocus. Is it allowed in this model? Ok to disabling face tracking.
    Not every camera allows this.  Typically, if available then they are in the first couple of menu option on the first tab in the Canon menu that gets displayed when the camera is in shooting mode.

    Quote
    5. Shouldn't I load the script via CHDK ALT mode? How do I load this script outside CHDK?
    It's a normal script so gets loaded the normal script way ( from the Script menu in CHDK <ALT> mode).

    Note :  I made a couple of small edits to my list of instructions.
    Ported :   A1200    SD940   G10    Powershot N    G16

    Re: Manual Focus @ Infinity not working
    « Reply #16 on: 29 / October / 2014, 15:17:44 »
    Thanks.

    Ok, here we go. Below, details from each of the three sequenced pics that resulted from this script execution:



    There must be a slight difference between the first two, but I honestly can't tell what it is. The last one is clearly blurred the same way as when I manually set CHDK focus @ infinity.

    The values:

    S/NL/FL-> INF/INF/INF
    DOF/HYP -> inf/1.01 (before halpressing the shutter to get focus); inf/2.87 (after halfpressing the shutter) (not really sure about this change because I had to look at many things at the same time  :blink: )

    (The values below were the same for the three pics)

    As for the mecha value

    1081 - 1082 - 1072

    SD @ 65,5

    From the Canon side, I switched to P and used the "Mountain & Face" option.

    What do you think?
    Canon A3100IS - 100d
    CHDK a3100-100d-1.2.0-3643-full_ALPHA

    Re: Manual Focus @ Infinity not working
    « Reply #17 on: 29 / October / 2014, 15:20:48 »
    Where you read

    Quote
    (The values below were the same for the three pics)

    read instead

    Quote
    (The values above were the same for the three pics)
    Canon A3100IS - 100d
    CHDK a3100-100d-1.2.0-3643-full_ALPHA


    Re: Manual Focus @ Infinity not working
    « Reply #18 on: 29 / October / 2014, 15:48:39 »
    Sorry about this, one more correction.

    When I said that SD was @ 65,5 I haven't noticed that it was displayed together with mecha.
    The correct readings are, for each one of the three landscape pics,

    infinity - 2.4m - infinity

    As for the short distance test, the SD/mecha values were:

    0.1 - 1253
    0.2 - 1176
    0.2 - 1176

    Before starting this test, I changed the script distance parameter to .3

    This time, none of the pics seem to be in their sharpest focus.
    Canon A3100IS - 100d
    CHDK a3100-100d-1.2.0-3643-full_ALPHA

    Re: Manual Focus @ Infinity not working
    « Reply #19 on: 29 / October / 2014, 18:43:21 »
    As for the mecha value
    1081 - 1082 - 1072
    Quote
    infinity - 2.4m - infinity
    These don't appear to match.

    But what this tells us is as follows :
    • The first image is done in autofocus mode - exactly the same as if you pressed the shutter button while not in <ALT> mode.
    • The second image is done with the camera in AFL mode and the focus set to infinity.
    • The third image is done with the camera in MF mode and the focus set to infinity.

    So the second image seems to demonstrate that the focus can be set to infinity via a script.  The third image displays the "softness" others have complained about when trying to set focus at infinity from a script.  In that image, the mecha position is past the infinity position of the other two images.   It's a little too soon to tell but this might explain why in some of the S100 tests I have seen, nothing is in focus in some of the shots (near, mid, or far object) with a tripod mounted shot.
    « Last Edit: 29 / October / 2014, 18:55:29 by waterwingz »
    Ported :   A1200    SD940   G10    Powershot N    G16

     

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