hello.
i have made some tests with full silent picture + stack focus. the setup was 550D + Sigma 150mm F/2.8
1/3 seconds exposure time is very good for macro photography in the early morning, when light is low, the wind is slow and the insects are slow because of the cold temperature. the idea is to take some similar picture like this one
http://www.fotonatura.ro/forum/album/eliz/insects/2010/IMG_24172-74-76-77-78.jpg.htmlthis is a report with problems that i have encountered
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(1) when shooting full silent picture, the lens aperture seem to be stuck wide open.
the camera was set to M mode (manual) and full silent DNG picture. changing the aperture from F/2.8 to F/8 (while ISO and exposure time constant) gives a picture with identical exposure. also the DOF (depth of field) seems to remain the same.
i have tried to press the DOF preview button with full silent picture activated in the ML menu, but instead of preview the aperture (in liveview), i got a picture.
turn off the full silent picture in menu, and the DOF preview seems to work ok, the image will turn dark on the screen when pressing the button.
proposed logic: keep the aperture open to make (first) autofocus, but when stating the stack process the aperture must be closed and kept like this (for minimize the shacking) up till the moment when the stack shoot is finish.
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(2) the whole process fullsilent + stacking, is to slow.
i made a test, it lasted 46 seconds for 5 stacked DNG silent pictures to take. this is quite to much time in realworld for the insect to stay unmoved or for the wind to not move the subject.
if you manage to capture 3 pictures at F11/F16 aperture in a short time like 5 seconds, will probably make this function to get good results in the realworld.
400ms to read the sensor + 1 second to review the picture + 6 seconds to write the DNG + 1 second to do refocus.
is there any way to use the buffer memory to take as many as pictures possible, and writing the pictures after that?
proposed logic :
a) do not wait for image data to be written on the card, before starting the re-focus process. instead use the camera buffer (similar with Canon firmware does on continuous shooting mode on mechanical shutter)
when the buffer is full, pause the stacking process, write the data to the card, clear the buffer, continue the stacking process
b) can live view be turned off while taking the stacked shots if this is speeding the capture process? (
like in this example ). once you made focus on insect, seeing the process on the screen is useless after you start running the Stack function.
c) image review can be turned off for faster speed. but it seems Magic Lantern show me the DNG picture on the screen after capture, even if Image Review is set to OFF in the Canon menu.
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as a conclusion, these two functions combination must be perfected for use in the realworld for stacked macro photography (i mean live subjects).
p.s. i observed that MLV are captured in 3 seconds which is an advantage, but i have used DNG for test to simply the conversion process, because i toked like 500 pictures for this tests. i have used shutter times between 1/10 and 0.8 seconds. no error 70 for me, or any kind of errors.