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  #16  
Old 02-16-2016, 02:41 PM
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Quote:
Originally Posted by old_tv_nut View Post
All good advice above.

Reasons why:

Regarding shutter speed: you need 1/30 of a second to capture a full NTSC frame. This is still too fast for good results because the start point and end point of the shutter opening will not be exactly synced to the TV and will show as a light or dark bar across the screen. This bar can be horizontal, diagonal, or other, depending on what sort of shutter mechanism (mechanical or electronic, vertical-moving or horizontal-moving) your camera has. Practically, you need to use 1/15 second or slower.
My Nikon Coolpix S3700 and other digital cameras I've worked with DO sync their shutters to ~60Hz light. I can point my camera at my TV screen with the basement fluorescent lights on, and it will synch to the flourescents (which are slightly off frequency from vertical scan frequency) instead of the TV and a rolling bar on screen will be seen with the camera...Kill the florescents and the bar instantly disappears as the camera syncs to the TV...If I use lights that do not flicker at 60Hz such as incandescent lighting or the sun the camera will always sync to the only source of flicker: the TV.
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  #17  
Old 02-16-2016, 05:23 PM
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Quote:
Originally Posted by Electronic M View Post
My Nikon Coolpix S3700 and other digital cameras I've worked with DO sync their shutters to ~60Hz light. I can point my camera at my TV screen with the basement fluorescent lights on, and it will synch to the flourescents (which are slightly off frequency from vertical scan frequency) instead of the TV and a rolling bar on screen will be seen with the camera...Kill the florescents and the bar instantly disappears as the camera syncs to the TV...If I use lights that do not flicker at 60Hz such as incandescent lighting or the sun the camera will always sync to the only source of flicker: the TV.
Cool!
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  #18  
Old 02-16-2016, 07:17 PM
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Quote:
Originally Posted by Electronic M View Post
My Nikon Coolpix S3700 and other digital cameras I've worked with DO sync their shutters to ~60Hz light.

Now that's a real feature! Expensive SLRs should have that as an option
in the menus. They should not be so hoitsy-toitsy as to not do it!
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  #19  
Old 02-16-2016, 09:16 PM
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The tripod is your friend.

I've always used content recorded on laserdiscs for displaying still frames because then I can turn the set brightness down and up the exposure time on the camera or better, use a lower ISO.
Realtime content typically involves a lot of experimenting. You need a shutter speed which as mentioned before is long enough to get a full sweep but not so long that the image blurs. The shot below is a live broadcast in black and white but took about 20 or so shots to get perfect.



Quote:
My Nikon Coolpix S3700 and other digital cameras I've worked with DO sync their shutters to ~60Hz light. I can point my camera at my TV screen with the basement fluorescent lights on, and it will synch to the flourescents (which are slightly off frequency from vertical scan frequency) instead of the TV and a rolling bar on screen will be seen with the camera...Kill the florescents and the bar instantly disappears as the camera syncs to the TV...If I use lights that do not flicker at 60Hz such as incandescent lighting or the sun the camera will always sync to the only source of flicker: the TV.
What mode is the camera in? Shutter Priority? Full-auto? That sounds more like the multi-point metering is just setting the shutter speed according to how much light it's picking up, not the frequency.
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  #20  
Old 04-25-2016, 06:17 PM
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Originally Posted by old_tv_nut View Post
...Reasons why:...
Another 'graduate-level' explanation from Wayne. Once again, I am less ignorant today than I was yesterday. THANKS!

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  #21  
Old 04-25-2016, 08:09 PM
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Another point - the automatic syncing to flicker rate can only be done with an electronic shutter (a point-and-shoot, or a DSLR in video mode). Mechanical shutters (film camera or DSLR with mechanical shutter in still mode) will generally have the shutter bar problem.
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  #22  
Old 04-25-2016, 08:15 PM
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now thats what a roundie should look like!i could watch that set forever
I have that same model of Zenith and that is exactly what it looks like. They are very comfortable to watch.
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