Shooting garden lighting

[StuH]

I've been trying to get some atmospheric shots of a garden at night. many of the trees and plants are lit with "PAR38" lights, the deck and other areas, a combination of blue LED, and white halogen.

I'm trying to strike a balance between keeping the background dark, but without underexposing the reflected light in the shadows. Also not sure if i should be shooting at high ISO, which helps with the shadows but off course introduces noise?

I've tried bouncing a flash from my 580EX but this kills the atmosphere of teh shot.

I'm using a 20D with 28-135IS, and a 10-22 EF-S

Any advice on suitable ISO/aperture/exposure.

[nick_bbb]

I would go for a 20-30 second exposure, on tripod, remote release, no flash, low ISO

[bramley]

^ What he said. Consider 'painting with light' with a torch during the long exposure if you need to boost light in certain areas or on certain objects.

[Shadytree]

I would try upto 2 minutes then scale back. Agree low ISO and no flash.

Took this in Thailand with the camera on a table with a remote shutter release, 60 second exposure.