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To use sync cable with CFV back...

salobaas

New Member
Hi,

I have a CFV with 503CXi and all works fine without cable. I have just a question on understanding if the sync cable would be helpful or not. As I understand the back stays "on" in the default setting for about 1/8 sec in which time the shutter opens and closes. When using a sync cable would the back only stay active between the two sync pulses, i .e. during the actual exposure time and hence have less change for hot pixels to show up? Or will it always be "on" for 1/8 sec?

Cheers, Fons.
 
<1/8 sec. setting

Fons

The setting <1/8 indicates the CFV , when set , that your exposure time is less than 1/8 sec . That could be any value between 1/8 and 1/500 .
If you want a longer exposure than 1/8 , you should set the value to the exposure time rate you are going to use .

I always use the sync cable , when I use longer exposures than 1/8 .
I don't know if it is required or recommended , but I do it to be on the safe side . That does not bother me , when I work from a tripod .

In the user manual it reads as follows :

EXPOSURE TIME
This setting should be changed for cable-free exposure times longer than1/8 second , enshuring that it matches the set shutter speed on the lens . The settings range from 1/8 second to 32 seconds .

The default setting is <1/8 second , because it is assumed , that you are shooting with a shorter exposure time than 1/8 , when shooting manual and not from the tripod .

I hope , this helps . Jürgen
 
Jürgen,

thanks for the feedback. That is what I also understand from the manual, and from that I conclude that the back is "on" for about 1/8s. Since the longer the exposure the more change on noise, I wondered if the back would be on for exactly the time dictated via the sync cable, i.e. maybe only 1/60 or 1/500. This could reduce the number of long exposure noise.

Cheers, Fons.
 
Jürgen,

I wondered if the back would be on for exactly the time dictated via the sync cable, i.e. maybe only 1/60 or 1/500. This could reduce the number of long exposure noise.
Cheers, Fons.

Fons

My understanding is , that the CFV back is "armed" for a time , a bit longer , than the set shutter speed .
I have done a lot of exposures longer than one second and never experienced any noise .
There are photographers here in the forum , who could report their experience with much longer exposure times than one second .

Jürgen
 
My understanding is:

1. The flash sync just serves to indicate that shutter is open.

2. CFV commense to take exposure after flash sync signal is received;

3. CFV exposure for 1/8 sec when "<1/8 sec" is selected, while correct exposure is controlled by shutter of camera/lens.
There is no communication between camera/lens with CFV and CFV has no knowledge of shutter speed but expose to 1/8 sec anyway. I.e. when 1/30 sec is set on camera/lens, it has effective expose of 1/30 sec while (1/8 - 1/30) sec will be expose in total darkness.

4. if longer shutter speed, say 1/2 sec, set by camera/lens while CFV is still set for "<1/8 sec", CFV is still expose to 1/8 sec and has effective exposure of 1/8 sec. That is, the effective exposure is lower of the camera/lens shutter speed and CFV exposure time.
 
Bottom line, with sync cable, is it armed only between the pulses when shorted then 1/8s?

Cheers, Fons.
I believe so. I use the cable all the time, since much of my exposures fall slower than 1/8th sec.
The back remains "on" until the shutter button is released - at which time you should hear a "beep."
Michael
 
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