Combined exposure and focus bracketing.

  • 38 Replies
  • 6830 Views
  • Publish
    Combined exposure and focus bracketing.
    « on: 14 / December / 2009, 10:11:58 »
    Advertisements
    Quote
    In the beginning I replaced the CHDK diskboot file with the SDM file and then downloaded the script. Was this enough?

    Yes, more than enough.

    Are you allowing enough time between each stack of exposures ?

    The camera did not seem to return the correct, initial focus value in the third set of readings ?
    « Last Edit: 14 / December / 2009, 10:13:39 by Microfunguy »

  • Publish
    Re: Combined exposure and focus bracketing.
    « Reply #1 on: 14 / December / 2009, 10:58:39 »
    The third stack started with pictures in which the closest object (macro) was blurry from the beginning, in the end of the third stack there are tens of pictures in which it seems pretty sharp.

    How can I change the time? I tried it now with the setting for first delay seconds being 10 and shoot interval seconds 15. The result looks like this:

    Time                       18:49:48

    Focal length         4.6
    Aperture             2.8
    Tv bracket           1/5

    Focused distances (from front of lens) 
    and step size                           

        45         0
        47         2
        49         2
        51         2
        53         2
        55         2
        57         2
        61         4
        65         4
        69         4
        75         6
        81         6
        89         8
        99        10
       112        13
       129        17
       153        24
       189        36
       247        58
       360       113
       671       311
      5170      4499
       Inf     60365
    ----------------------------------------------

    Time                       18:50:13

    Focal length         4.6
    Aperture             2.8
    Tv bracket           0.8

    Focused distances (from front of lens) 
    and step size                           

        44         0
        46         2
        48         2
        50         2
        52         2
        54         2
        56         2
        59         3
        63         4
        67         4
        72         5
        78         6
        85         7
        94         9
       105        11
       120        15
       140        20
       169        29
       214        45
       293        79
       468       175
      1184       716
       Inf     64351
    -----------------------------------------

    Time                       18:50:51

    Focal length         4.6
    Aperture             2.8
    Tv bracket          1/20

    Focused distances (from front of lens) 
    and step size                           

        30         0
        31         1
        32         1
        33         1
        34         1
        35         1
        36         1
        37         1
        38         1
        39         1
        40         1
        41         1
        42         1
        44         2
        46         2
        48         2
        50         2
        52         2
        54         2
        56         2
        59         3
        63         4
        67         4
        72         5
        78         6
        85         7
        94         9
       105        11
       120        15
       140        20
       169        29
       214        45
       293        79
       468       175
      1184       716
       Inf     64351


  • Publish
    Re: Combined exposure and focus bracketing.
    « Reply #2 on: 14 / December / 2009, 11:21:48 »
    Now I tried with equal stacking and not auto stacking:

    First delay seconds                    5
    Shoot interval seconds               5
    Number of repeats                     1
    Endless mode N/Y                      0
    Single/Cont/Time/Burst              1
    Tv exposures                             7
    Focus exposures                        15
    Bracket Tv/foc/Both                   2
    Light/Dark/Alternate                  2
    Num of 1/3 EV steps                  6
    Equal/auto/digi 0/2                    0
    Focus-step                              50
    digiscope focus ref                  500
    Blank screen N/Y                      0
    Shutdown N/auto/USB               0
    Save stack N/Y                         1
    Sunrise mode                           0
    TXT/CSV                                  0

    It was supposed to give me 7 different exposures with 15 different focuses each, this is what happened:

    Time                       19:11:17

    Focal length         4.6
    Aperture             2.8
    Tv bracket           1/5

    Focused distances (from front of lens) 

        34
        84
       134
       184
       234
       284
       334
       384
       434
       484
       534
       584
       634
       684
       734
    ---------------------------------------

    Time                       19:11:34

    Focal length         4.6
    Aperture             2.8
    Tv bracket           0.8

    Focused distances (from front of lens) 

        31
        81
       131
       181
       231
       281
       331
       381
       431
       481
       531
       581
       631
       681
       731
    --------------------------------

    Time                       19:11:59

    Focal length         4.6
    Aperture             2.8
    Tv bracket          1/20

    Focused distances (from front of lens) 

        33
        83
       133
       183
       233
       283
       333
       383
       433
       483
       533
       583
       633
       683
       733
    --------------------------------------

    Time                       19:12:19

    Focal length         4.6
    Aperture             2.8
    Tv bracket          2.5"

    Focused distances (from front of lens) 

        30
        80
       130
       180
       230
       280
       330
       380
       430
       480
    --------------------------------------------


    So it worked fine the first 3 exposures, the 4th it took only 10 different focus points, and it just skipped the final 3 exposures completely.

  • Publish
    Re: Combined exposure and focus bracketing.
    « Reply #3 on: 14 / December / 2009, 12:15:45 »
    But you have only set the time interval to five seconds.

    With an exposure of 2.5 seconds, the Canon firmware adds another 2.5 seconds for dark-frame subtraction.

    Increase the time interval.



  • Publish
    Re: Combined exposure and focus bracketing.
    « Reply #4 on: 14 / December / 2009, 13:57:25 »
    With the same equal stacking settings I just posted I set the shoot interval to 5 minutes and it still only took 4 different exposures, now 15 pictures with the first 3 and 18 with the 4th. It still won't take more than 4 exposures.

  • Publish
    Re: Combined exposure and focus bracketing.
    « Reply #5 on: 15 / December / 2009, 09:27:42 »
    Am I still doing something wrong or doesn't the script just work with the 860?

  • Publish
    Re: Combined exposure and focus bracketing.
    « Reply #6 on: 15 / December / 2009, 09:44:04 »
    I will check it out.
    May take a few days.



  • Publish
    Re: Combined exposure and focus bracketing.
    « Reply #7 on: 15 / December / 2009, 09:51:48 »
    I will check it out.
    May take a few days.




    Thank You! If you need more parameters or settings tested just let me know.


    *

    Offline fvdk

    • ***
    • 144
    • Ixus 70 1.01b / 1.02a & Powershot A590is 1.01b
      • My Flickr photo page
  • Publish
    Re: Combined exposure and focus bracketing.
    « Reply #8 on: 15 / December / 2009, 16:41:22 »
    It seems that there are a few bugs so lets hope that David will figure them out. At the moment it seems that a script stops as soon as the camera reaches it's native longest shutter speed.

    In the mean time, here is some explanation of the different parameters and how they work in different situations or in different combinations.

    number of repeats

    This determines how many times a sequence of events is repeated.
    A sequence of events can be:

    A single picture, repeated every X seconds where number of repeats determines how many pictures are taken and shoot interval seconds and / or shoot interval minutes determine how much time there will be between each exposure.
    If however, Endless mode N/Y is set to Y, number of repeats will be ignored and pictures will be taken until the script is stopped.

    A focus stack.
    In this case, number of repeats is probably only useful if you want to make stereo pictures. Lets say that you only want a stack of pictures with focus from the nearest object till infinity, than there would be no use to repeat that sequence as that would only give you the same result twice. shoot interval in this case is ignored because there is just 1 sequence.
    If however, you would like to make a stereo picture than you would need the same stack but you will want to shift the camera between each stack. So, in this case you will set number of repeats to 2. in this example, shoot interval determines after which time the recording of the second stack will start. In order to determine how long the interval should be, it is advised to first record one stack and note how long it takes to complete.
    Lets suppose the time needed to complete the stack is 1 minute and you want to have 30 seconds to shift the camera before the next stack will be recorded, you will set the shoot interval to 1 minute and 30 seconds.

    A series of bracketed pictures.
    In this case, number of repeats will also be 1 as you will only need one picture but with different exposures.

    A focus stack combined with bracketing. In this case, number of repeats will also be 1 as you will only need one focus stack but than combined with bracketing so in this case, Tv exposures determines how many different exposed stacks you will get. Num of 1/3 EV steps determines the f-stop difference between the different exposed stacks.
    shoot interval is ignored since it is still 1 repeat of a sequence.

    Endless mode N/Y

    If set to Y, parameter number of repeats is ignored and the script will run until stopped.

    Single/Cont/Time/Burst

    This determines if a single image will be taken, if the camera will be used in continuous mode, with the cameras Custom Timer or in burst mode were images will be taken as fast as your camera continuous-shooting mode will allow.
    Note that for a bracketed sequence, the camera needs to be in continuous-shooting mode.

    Tv exposures

    This determines how many exposure bracketing images or sequences will be taken and works in conjunction with Num of 1/3 EV steps.
    So if you want a bracketed sequence of 0EV, -1EV, +1EV (3 stops) you will set Tv exposures to 3 and Num of 1/3 EV steps to 3. If you set Tv exposures to 5, you will a sequence of 0EV, -1EV, +1EV, _2EV, +2EV

    Focus exposures

    This setting determines how many pictures you want to take for a focus stack and works in conjunction with Equal/auto/digi 0/2 and Focus-step.
    For example, if you want 5 pictures, with an equal focus step of 50mm, you would use the following settings:
    Focus exposures = 5, Equal/auto/digi 0/2 = 0 and Focus-step = 50
    However, if you set Equal/auto/digi 0/2 to 1 (auto) both of the other settings will be ignored and the camera will automatically take a stack of pictures focused from the nearest subject to infinity.

    A few things are important to remember:
    The camera needs to know at what distance and which exposure it should start the sequence. So you should first make the required settings in the script and than exit ALT mode. Than point your camera at your subject and half-press the shutter so your camera will focus and calculate the exposure. Now go into ALT mode again where your script is still loaded and execute it.

    Save stack N/Y

    If set to Y, a text file with the results of each bracketing sequence will be saved in the STACKS folder on the card. 

    A few examples and the combination of settings required for them

    To take an automated focus stack from the nearest subject to infinity:
    • Number of repeats = 1
    • Single/Cont/Time/Burst = 1
    • Bracket Tv/foc/Both = 1
    • Equal/auto/digi 0/2 = 1
    The camera needs to be in continuous-shooting mode !

    To take an automated focus stack from the nearest subject to infinity and also bracket the stack with 5 stops:
    • Number of repeats = 1
    • Single/Cont/Time/Burst = 1
    • Tv exposures = 5
    • Bracket Tv/foc/Both = 2
    • Equal/auto/digi 0/2 = 1
    • Num of 1/3 EV steps = 3

    This will result in an automated focus stack, repeated 5 times with 0EV, -1EV, +1EV, -2EV, +2EV

    As an alternative, set Tv exposures = 5 to 3 and Num of 1/3 EV steps to 6

    This will result in an automated focus stack, repeated 3 times with 0EV, -2EV, +2EV

    The camera needs to be in continuous-shooting mode !

    To make a simple time-lapse sequence with 100 images with an interval of 3 seconds
    • Shoot interval seconds = 3
    • Number of repeats = 100
    • Single/Cont/Time/Burst = 0

    Alternatively, set Endless mode N/Y to Y and the camera will take pictures until the script is stopped.

    Optionally, set Blank screen N/Y to Y
    The LCD backlight will be turned-off and only very briefly turns-on after each exposure.

    The camera must be in single shooting mode.

    For extended explanation of the different parameters, see http://stereo.jpn.org/eng/sdm/tlapse.htm

    Have fun !







     

  • Publish
    Re: Combined exposure and focus bracketing.
    « Reply #9 on: 16 / December / 2009, 18:43:06 »
    @whatevertsunami:

    Can you download this version and continue your tests ?  :-

    http://www.zshare.net/download/699813481f2a6ba5/

     

    Related Topics