Olympus-OM
[Top] [All Lists]

Re: [OM] rear curtain sync??

Subject: Re: [OM] rear curtain sync??
From: *- DORIS FANG -* <sfsttj@xxxxxxxxxxxxxxxxxxx>
Date: Fri, 4 Feb 2000 15:50:58 -0500 (EST)

On Fri, 4 Feb 2000, Dirk Wright wrote:

> Assuming that the above is correct, I can't think of the difference it 
> would have on picture taking. For really slow shutter speeds, the stuff 
> illuminated by ambient light would be blurred from movement, and the 
> flash illuminated stuff would be sharp. For normal sync, it seems that 
> the ambient stuff is recorded after the flash fires. For rear curtain 
> sync, the ambient stuff would be recorded before the flash fires. I'm 
> not sure what difference this would make. Anyone? 

  The effects are very different (though not necessarily better
or worse) between the two. With normal synch, the flash goes off, 
then things trail. With rear synch, it is the opposite. 
  With a non-moving subject, there's not much difference, but with a 
moving one...

   Let's say you have a dog running  thusly:

            <-------------------<<<

   To see the difference, you're going to have to be at a lower
synch speed (depending on how fast the dog's running and the angle
of the vector in relation to the lens axis, but let's not complicate
matters TOO much). Let's say you choose to illustrate motion
and the ambient light is low enough to let you go at 1/8th.

       # = Shutter opens

       * = Moment flash goes off

       + = Moment shutter closes

  With normal synch:
           <-------- will appear blurred -------->  
   <---- + --------------------------------------- * # --------<<<
                                    
  Rear Curtain synch:
             <------ will appear blurred ---------->
   <---- + * --------------------------------------- # --------<<<              
    
      
  The results are very different, and which you use depends on 
what you want. I find that when a shot is gesture-critical, timing
wise, rear-curtain is tough to pin down. But the blur leading up
to the flashed figure is what many people are used to in the
depiction of motion, which is why 2nd curtain is a good option to
have. Perhaps because we love best that which we loved first, I 
tend to prefer normal synch most of the time.

                                *= Doris Fang =*








 


< This message was delivered via the Olympus Mailing List >
< For questions, mailto:owner-olympus@xxxxxxxxxxxxxxx >
< Web Page: http://Zuiko.sls.bc.ca/swright/olympuslist.html >


<Prev in Thread] Current Thread [Next in Thread>
Sponsored by Tako
Impressum | Datenschutz