when is exposure time measured

[tomasga]

I have an intensifier tube on the front of my Canon D30 that comes on a split second after I press the shutter release button to take a picture. For example, when I press the button there is no light entering the camera, therefore it decides it needs a longer exposure time than needed even though the intensifier tube comes on before the picture is taken. I have tried the self-timers, but they too seem to set there exposure time right after the shutter release button is pressed. Does anyone know how to delay when the exposure time is set?

Thanks

[mdavids]

The camera will normally meter the scene when the shutter button is pressed halfway. If you want it to meter after you press the shutter, you're out of luck. You can always set manual exposure based on the histogram of your shot, or you can have your intensifier come on earlier. I think those are your only options.