the double shutter speed rule ruins your video

Started 5 months ago | Discussions thread
John Brawley Contributing Member • Posts: 765
Re: the double shutter speed rule ruins your video
2

Svetlov Misha wrote:

John Brawley wrote:

24 FRAMES per second.

so, with a 180 degree shutter, HALF of the second, or 0.5 seconds is being exposed 24 times

to be clear... half of the sec contains 12 frames... are you sure you know what are you talking about?

Yes. Over the TIME interval of a second, half of the time the shutter is OPEN and lines are being recorded.

The other half of the second is dormant.

This in total. This happens in 1/48th intervals OVER a second.

Here is a break down of that over a single second...

1/48th - Shutter is open

1/48th - Shutter is closed

1/48th - Shutter is open

1/48th - Shutter is closed

1/48th - Shutter is open

1/48th - Shutter is closed

1/48th - Shutter is open

1/48th - Shutter is closed

1/48th - Shutter is open

1/48th - Shutter is closed

1/48th - Shutter is open

1/48th - Shutter is closed

1/48th - Shutter is open

1/48th - Shutter is closed

1/48th - Shutter is open

1/48th - Shutter is closed

1/48th - Shutter is open

1/48th - Shutter is closed

1/48th - Shutter is open

1/48th - Shutter is closed

1/48th - Shutter is open

1/48th - Shutter is closed

1/48th - Shutter is open

1/48th - Shutter is closed

1/48th - Shutter is open

1/48th - Shutter is closed

1/48th - Shutter is open

1/48th - Shutter is closed

1/48th - Shutter is open

1/48th - Shutter is closed

1/48th - Shutter is open

1/48th - Shutter is closed

1/48th - Shutter is open

1/48th - Shutter is closed

1/48th - Shutter is open

1/48th - Shutter is closed

1/48th - Shutter is open

1/48th - Shutter is closed

1/48th - Shutter is open

1/48th - Shutter is closed

1/48th - Shutter is open

1/48th - Shutter is closed

1/48th - Shutter is open

1/48th - Shutter is closed

1/48th - Shutter is open

1/48th - Shutter is closed

1/48th - Shutter is open

1/48th - Shutter is closed

And then within each OPEN shutter cycle....

Shutter is open for 1/48th of a second...

1st line is recorded

-- hide signature --

2nd line is recorded

----3rd line is recorded

------4th line is recorded

--------5th line is recorded

----------6th line is recorded

------------7th line is recorded

--------------8th line is recorded

----------------9th line is recorded

------------------10th line is recorded and so on depending on the resolution of the sensor.

Each line is recorded AT A DIFFERENT TIME within the single 1/48th of a second allocated to record that single frame. Each of the slightly different time recorded lines are assembled to make a single frame but the TOTAL TIME TAKEN to record that frame is still 1/48th of a second.

You flash might occur across lines 1- 4 in this case the first time and then in the same frame at lines 8-10 OR it might cross a frame boundary. You don't know because your strobe isn't starting at the same time and isn't synced to the frame count.

When you record at higher frame rates, the timing of when those lines are recorded CHANGES so the overlap of each strobe on those random lines will also change.

.. are you sure you know what are you talking about?

Are you?

JB

 John Brawley's gear list:John Brawley's gear list
Leica M8 Leica M-E Typ 220 Olympus E-M5 II Olympus E-M1 II Leica M10 +37 more
Post (hide subjects) Posted by
Keyboard shortcuts:
FForum PPrevious NNext WNext unread UUpvote SSubscribe RReply QQuote BBookmark MMy threads
Color scheme? Blue / Yellow