Nikon D90 rear curtain sync will shoot flash twice

First, you have to be in one of the PSAM modes; in the other modes the camera decides whether it needs the flash and in daylight it will decide there's enough light without it. So, after turning the model dial to one of the PSAM positions, press the flash button on the front of the camera to pop up the flash. In these modes the camera will fire the flash if it's popped up, and not if it's down.

To change the flash mode, hold down the flash button (after it's popped up) and turn the command dial. Depending on the chosen exposure mode, your choices may include Fill flash, Red-eye reduction, Rear-curtain sync, Slow sync, Rear-curtain plus red-eye reduction, and Rear-curtain plus slow sync. Refer to the "Flash Mode" section of the manual for full details.

Hi You might need this information. I could write but online informations are very helpful and save time. http://www.digital-photography-school.com/slow-sync-flash
thanks and best regard!

Set the exposure mode to Manual (M) or Shutter-priority (S) and specify the shutter speed yourself. You'll have to set it sufficiently slow in order to see any difference between front- and rear-curtain.

Hi Vilas,
All of those cables will not do. Your Nikon D90 has no PC Socket. Buy a NIKON AS-15 and then just hook Flash Sync Cable to AS-15.
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Check that the terminals on the flash and the camera foot are clean Use a pencil eraser to clean thyem by using a gentle rubbing motion. reconnect and test.


Please rate my help++++Thanks for using FIXYA

If your doing what I think you are then, It sounds like the flash is set too act as a commander for the off-camera CLS flash setup. Check setting e3 and put it in TTL mode. It's called rear or 2nd curtain flash sync.

No. The high trigger voltage in your old unit will damage your D90 for certain.

You need to get a newer flash (US=strobe) designed for digital cameras but don't have to stick to Nikon's overpriced offerings. Metz are excellent and have a high resale value as you can change the dedication model to suit different manufacturers.

Definately a settings problem. The camera will only syncronize on one specific speed. Youe best bet is to use auto. For manual, you'll have to set the shutter speed at the sync speed.

Flash Sync Speed

up to 1/250 X-Sync Speed

up to 1/8000 FP High Speed Sync

Red-eye reduction
Red-eye reduction with slow sync
Rear-curtain sync
Slow sync
Front-curtain sync (normal) Flash Sync Modes

1) i-TTL: TTL flash control by 1,005-pixel RGB sensor, built-in flash, SB-800, SB-600, SB-400: i-TTL balanced fill-flash and standard i-TTL flash
2) AA (Auto Aperture-type) flash: Available with SB-800 used with CPU lens
3) Non-TTL Auto: Available with Speedlights such as SB-800, 28, 27, and 22S
4) Range-priority manual flash; available with SB-800 Flash Control

Make sure the slave is not set to rear curtain or slow flash. Otherwise Send that back to Nikon for service. http://www.nikonusa.com/Service-And-Support/Service-And-Repair.page

This can be that the flash sync speed of the camera is not correct. There may not be enough exposure from the flash to the subject during the opened curtain (shutter) sequence.


Jerry G.