*ist ds problem

Hi, I have just bought a used *ist ds and been playing around with it taking a few flash photos and just noticed something weird, I put it on manual and set the shutter speed at 180 started taking photos (with flash) at f5.6 but as I increased the f number it got brighter each time until f20 was greatly overexposed, I kept the shutter speed at 180 all the time, am I going mad, shouldn't it work the opposite way round and am I doing something really stupid help! jacqui.

just tried without flash as well and in manual mode kept the shutter speed on 125 and as I increased the f number made no difference at all, went from f5.6 to f40, kept the shutter speed at 125 and made no difference to the resulting image

Sounds to me like the lens is not stopping down
(i.e. the camera is thinking it is selecting f/16, but in reality the aperture blades are not closing in)

Have you another lens to try (just to eliminate that)?
(You can remove the lens and actuate the aperture 'finger' manually to see if the lens is ok)

Matt

thats what i was thinking /hoping, I have a new lens bought from forum member here turning up in about an hour so I will give it a try, thanks, jacqui.

Hi, it was the lens, when I took it off the lever at the side is very sticky, doesn't move freely at all, so that's going back, got my new lens on now and that works fine.

Glad you got it resolved