Using ISO outside its "native" range for your camera

[jamesbjenkins]

Hey all,

I just got my hands on a D3 (woo hoo!) and I've been going through everything from scratch all over again. On all my previous cameras, I've never fiddled with setting the ISO outside its native range. I know Nikon uses weird terminology (Lo 1, Hi 1, Hi 2, etc.), and I understand that with these settings, the camera is somehow "pushing" the sensor outside its native range. I understand all too well what happens when you push ISO on the high side. The noise gets ugly pretty quick. However, I have no idea how the camera behaves if you're on the low end.

If any of you guys regularly push your camera outside its native range on the low end, what can you tell me about it? Other than a marginal improvement in noise, are there any benefits of using Lo 1 aka ISO 100 if the native range is only ISO 200-6400?

 

[KmH]

ISO inside the native (base) range is accomplished with signal gain (multiplication factor by electronic amplification).

ISO outside the base range is done entirely with software, and a substantial loss of dynamic range often results when less than the base ISO range is selected.

 

[jamesbjenkins]

I figured there'd be a loss in DR. Doesn't sound like there's much of a benefit to pushing it on the low end.