I try to get the slow sync effect that you usually get on some point and shoot camera with the M6TTL ans SF20, just don't know how, can anyone help? Thanks!!

-- Mitchell Li (mitchli@pacbell.net), January 06, 2002

Answers

If you mean the slow shutter speed to allow for ambient fill in darkish circumstances with flash to freeze the foreground, just set a slow shutter speed ...

-- Godfrey (ramarren@bayarea.net), January 06, 2002.

But you can't get rear curtain sync, if that is what you are asking.

-- Phil Stiles (Stiles@metrocast.net), January 06, 2002.

Assuming you are looking for rear curtain sync, depending on the subject and the ambient light level, you might try a short "bulb" exposure and firing the flash manually (cable release in one hand, flash fired with the other in one-two fashion). That would be difficult to physically coordinate, however, and the results would be subject to wide variation. Cartainly not as reliable as rear sync programmed on an electronically controlled SLR shutter.

-- Ralph Barker (rbarker@pacbell.net), January 06, 2002.

Could you please update me on the meaning of "rear curtain sync"...?

-- Lutz Konermann (lutz@konermann.net), January 07, 2002.

Lutz,

In the first cameras with focal plane shutters, the flash would fire as soon as the first curtain was fully open on a sync speed or slower. The problem with that is that for longer exposures, with subject movement, the "ghosting" of ambient lit subject (usually a blur), would be in front of the frozen flash exposed rendering. This looks somewhat un-natural, since movement streaks are usually behind the subject.

Rear curtain flash allows most of the shutter time to occur without the flash firing, until the last micro second before the shutter starts to close (second or rear curtain), which allows the blurred ambient streak to be behind the frozen subject, which looks more natural.

The value of this is dependant on the duration of the shutterspeed, and the subjects movement. Just having the option for rear curtain flash allows some experimenting for effects that can look interesting. Instead of 1/250th of a second flash sync, you can close the aperture and let the shutter stay open longer, with the flash only being responsible for a portion of the exposure and ambient light being responsible for the rest... all on the same frame. Success is hit or miss, but when it works, it looks good.

-- Al Smith (smith58@msn.com), January 07, 2002.

Al,

Thanks for the clarification. I was a bit confused at first by your "in front" and "behind" concept of movement-streaks, suggesting an inevitably *spatial* phenomenon, but read as "before" and "after" in relation to the *time*line of a clearly defined, more or less linear movement it does absolutely make sense to me, now. I do know and like this effect as it may in fact add a dimension to an otherwise "frozen" image, but for my interpretation more one of time than one of space, as I said. However, I didn't know about this rear curtain sync technique with modern cameras, which you describe. I wonder how helpful this may be if the subject turns away after releasing (and before the end of a slow shutter speed exposure)...?! So, I guess that this technique - if available - should be optional, anyway.;o) Cheers.

-- Lutz Konermann (lutz@konermann.net), January 07, 2002.

Hi Mitchell! If I understand correctly, the question refers to combining ambient light with flash at relatively low light levels. The SF-20 is a perfect tool for this technique. When I'm working "handheld" with a moving (or stationary) subject with a shutter-speed range of 1sec. to around 1/30th, I'll set the SF-20's exposure compensation for a half to full stop underexposure, metering for ambient light as usual, so that the flash effect is somewhat subdued. This gives the image a wonderful feel of movement, along with just enough "flash-frozen" detail to add interest. My advice is to experiment with different ratios of ambient-to-flash exposure levels, and maybe take notes for your first roll or so of trials. Before long, this process will become second-nature. Good luck! - John

-- John Layton (john.layton@valley.net), January 07, 2002.