1 Curtain slow sync vs X-sync

Started Sep 8, 2013 | Discussions thread
WFulton Senior Member • Posts: 2,697
Re: 1 Curtain slow sync vs X-sync

Aoresteen wrote:

If I select 1st curtain slow sync and set the shutter speed to 1/250 sec, is this the same as x-sync at 1/250 sec?

My camera in manual mode ONLY allows me to select SLOW SYNC or OFF. Regular sync is not available. I'm using an older strobe with the camera (with a Wein SafeSync adapter due to the the strobe's high sync voltage).

I can set the SLOW to 1st curtain or 2nd curtain. I think I want 1st curtain.


That sounds reasonable.  All electronic flash is X sync (immediate, no delay - as opposed to flash bulbs).

Slow sync and rear curtain sync is X also, but is about something else.

In camera A or P modes, most cameras will set a Minimum Shutter Speed when flash is used, about 1/60 second.   Suppose in an indoor situation, with the flash turned off, suppose the camera aperture is f/5.6 and exposure meters 1/2 second (because it is dim where you need flash).  But reach up and turn on the flash, and the shutter speed jumps to this Miniumum with flash (typically 1/60 second).  Because, you are using flash, and you have no use for 1/2 second.

I am specifically speaking of Nikons, but nothing else is reasonable..

Slow Sync simply bypasses the Minimum shutter and retains the metered 1/2 second shutter (for the ambient... the flash could not care less about shutter speed).  This is for if you care about proper full ambient exposure.  Normally indoors, we don't.

Rear Sync bypasses the minimum also.  Rear sync makes no sense without a slow shutter causing blur from ambient.   So we want Rear sync to put the long blur trail "following" the flash, instead of leading it (as is normal, for normal front sync).

In camera Manual mode, the shutter stays wherever you set it... Automation does not change it.

So then, nothing but Slow Sync makes any sense (it certainly does not set a faster Minimum).

Keyboard shortcuts:
FForum PPrevious NNext WNext unread UUpvote SSubscribe RReply QQuote BBookmark MMy threads
Color scheme? Blue / Yellow