The SX1 IS Porting Thread

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Offline reyalp

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    Re: The SX1 IS Porting Thread
    « Reply #370 on: 15 / August / 2010, 14:03:35 »
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    Hi,
    First:
    The auto ISO works pretty well in AV mode except that the picture is always over-exposed by about 2 EL. That means that i CANNOT under-expose my shots since even at a manual setting of -2 EL, the obtained exposition is equivalent to 0...
    -> Is there a way to correct (shifting) the exposition in the CHDK Auto-ISO mode ? I looked at the source code (but i'm not a programer...) and i didn't see this parameter when shooting in auto-ISO mode...

    Second:
    In manual ISO value overriding, the lower ISO value i get is 10, in AutoISO it's 16, even when the minimal set value is 10... -> is that an expected behaviour ?

    Thanks for reading this and maybe answering me.
    And thanks for all the devs/testers here...

    K.
    I'm curious what testing you've done to verify that these super low ISO values actually work. On all the CCD based powershots, ISO override below the factory minimum appears to have no effect. See http://chdk.setepontos.com/index.php/topic,3373.0.html for a detailed test.

    The fact that the values appear in the exif is not evidence that it is working.

    The most reliable way to determine how well the ISO override works would be examining the raw pixels values of exposures taken in the same lighting with only the ISO changed.

    The override not working would explain the shots with extreme override being over exposed, and 16-80 is just over two stops.
    Don't forget what the H stands for.

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    Re: The SX1 IS Porting Thread
    « Reply #371 on: 15 / August / 2010, 16:33:57 »
    Thanks Reyalp for the input, and for leading me to this ISO thread.
    I clearly did NOT test the ISO override function extensively as was away from nearly all source of technology these days (apart from the SX1...). I just compared the result with the magnification option on the LCD screen... and i saw the difference between "standard ISO 80" and "CHDK ISO 16". But i didn't test it to see what was really the thresold and the real "CHDK minimum ISO value".

    And for my question : it may indeed explain the "bad" exposure i get...

    I test it (even if only roughly) asap and i report back.
    Thanks again.
    « Last Edit: 16 / August / 2010, 13:00:21 by knib »

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    Re: The SX1 IS Porting Thread
    « Reply #372 on: 15 / August / 2010, 17:04:35 »
    1)
    I can't test the ISO feature deeply now.
    As an illustration, here are two shots i have close at hand. Same subject, same exposure. The first with "standard" ISO 80, the second with "CHDK" ISO 16. They were both shot in jpeg [haven't any good RAW for this atm], so they underwent the same image processing (i.e. : strong and clumsy noise reduction and sharpening). They are cropped/100%:



    You can see the improvement in the importance of the noise with the lower ISO.

    2)
    I tested quickly various CHDK ISO settings. By quickly, i mean that i only use the image luminosity to judge the action of the ISO parameter. It seems that the lowest ISO value is 50 or 64 (below, all the pictures have the same luminosity).

    3)
    It seems that, by setting the minimum auto-ISO value to be 50 [it needs to be set to 3 x 10  in the options], the exposure of the shot is OK. So, the calculation was fooled by the fact that all ISO values inferior to 64 do NOT decrease sensitivity.

    Thanks again for the answer. I hope these informations can help other CHDK/SX1 users...
    « Last Edit: 14 / September / 2010, 04:59:14 by knib »

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    Re: The SX1 IS Porting Thread
    « Reply #373 on: 07 / January / 2011, 11:49:50 »
    Hi

    I'm a newbie in CHDK (using the full beta 2.00H version on a SX1) .
    I would like to know how to toggle overrides /no overrides, since when I use the shortcut half press + left the only thing I'm able to do is to toggle on/off zebra display.

    Best regards


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    Re: The SX1 IS Porting Thread
    « Reply #374 on: 09 / July / 2011, 07:53:17 »
    Hi all,

    is it possible to change the Canon SX1 firmware in order to I have ability to start/stop video recording using USB remote? For now USB remote shots photos in all modes inculuding "Video". :(

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    Offline reyalp

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    Re: The SX1 IS Porting Thread
    « Reply #375 on: 09 / July / 2011, 15:47:03 »
    Hi all,

    is it possible to change the Canon SX1 firmware in order to I have ability to start/stop video recording using USB remote? For now USB remote shots photos in all modes inculuding "Video". :(
    You could use a script.
    Don't forget what the H stands for.

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    Re: The SX1 IS Porting Thread
    « Reply #376 on: 09 / July / 2011, 16:04:04 »
    I woul
    Hi all,

    is it possible to change the Canon SX1 firmware in order to I have ability to start/stop video recording using USB remote? For now USB remote shots photos in all modes inculuding "Video". :(
    You could use a script.
    I would be glad to use a script, but where to find it? I tried to change the standart "Remote" script, for example:

    @title Video button
    :loop
    wait_click 1
    is_key k "remote"
    if k=1 then click "Video"
    goto "loop"
    end

    , but no effect. It seems, Canon SX1's chdk does not understand word "Video". :-(

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    Offline reyalp

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    Re: The SX1 IS Porting Thread
    « Reply #377 on: 09 / July / 2011, 16:36:58 »
    try "video" with a lower case v

    also
    if is_key "remote" then ...
    Don't forget what the H stands for.


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    Re: The SX1 IS Porting Thread
    « Reply #378 on: 09 / July / 2011, 20:29:41 »
    I
    try "video" with a lower case v

    also
    if is_key "remote" then ...

    I have tried a lot of combinations, but only one was executed without errors but no action was called:

    @title Video9 button

    while 1
        wait_click 1
        if is_key "remote" then click video
    wend

    end


    Any other propositions?

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    Re: The SX1 IS Porting Thread
    « Reply #379 on: 10 / July / 2011, 07:29:36 »
    After next series of experiments I found 3 approaches to start video record using usb-remote in Canon SX1. First two are based on standart 2.00H firmware, 3rd is based on SDM 1.85 firmware. Using standart 2.00H firmware you could create two following scripts (in 2 different files):

    1. Video1.bas:
    @title Video5 button while 1 wait_click 1 if is_key "remote" then click "video" wend end

    Open the Notepad, insert the abovementioded string and save under name video1.bas

    2. Video2.bas:
    @title Video5 button while 1 wait_click 1 if is_key "remote" then press "video" wend end

    Open the Notepad, insert the abovementioded string and save under name video2.bas


    3. Video3.bas
    :: use the script from the following url: http://tech.groups.yahoo.com/group/StereoDataMaker/message/8212

    you can store formatting.



    After experimenting with scripts #1 and #2 I noticed then the 1st script starts always but stops recording after 1-3 sec
    if you did press the usb-starter's button more then 0.2-0.3 sec. If you pressed quickly then recording goes successfully.

    Script #2 starts successfully at 100% cases and recording goes on, but in order to stop record you need stop script by "shoot" button, run it again and click usb-starter's button. It would be good to develop this script next in order to eliminate pressing "shoot" button twice.


    I hope this info will be useful.

     

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