nikon d40 - Why is the shutter speed so long when using the flash in aperture priority?

I'm trying to get the background out of focus (bokeh) and using Aperature(A) mode and setting aperture to lowest value.

Update: I'm shooting in dim light and the flash goes off but the shutter speed incredibly slow (1-2 seconds), even slower than if I put it in full auto (where, presumably, the Aperture would be no wider than in Aperture mode with maximum Aperture .

I did find something in my Nikon Df0/D40X Digital Field Guid (by Busch) that said that in Aperture priority, the shutter speed is limited to 1/60s up to Syc speed. So I assume that means no slower than 1/60s

Here are the photos:

Aperture Priority with Flash (2s Shutter time)

• Exposure : 2s


• F/5.6


• Focal Length: 120mm


• ISO: 100

Full Auto

• 
  

  Exposure : 1/60 s

  
  
  


• 
  

  F/5.6

  
  


• 
  

  Focal Length: 135mm (Ok, that's a little different)

  
  


• 
  

  ISO: 200

  
  

Answer

This is called Slow Sync, which is a technique that allows you to combine flash with an ambient light exposure.

You probably turned this on by mistake. Generally, that's by holding the flash button (the one that pops up the flash) and turning the control wheel.

Your manual is here, see page 47 (in the PDF, technically pg 35 in the actual manual).