I just manual focus to infinity and use live view to setup the composition, live view generally boosts ISO for the sake of being able to see at night so even with welding glass over the lens you can see enough to compose. I also set the exposure to just before the camera says it's +3 EV, it's wring most of the time because it doesn't understand what's going on lol, basically you shoot full manual, no metering, no AWB, no AF, you have to tell the camera exactly what it needs to do. Plus in the white balance should boost green tint and cold temperature, manual white balance setup is a must with the ND110 F9-F14 Is generally where you should take the shot, I say this, because if the aperture is too low, it over exposes, too high and the lens is at it's worst in terms of optical quality. With F14 you can shoot daytime for a full minute without issues, it will vary though. F10\30Secs works well too
thank you i wrote all that down will have to try that, when i use live view it is still pretty dark though and with the white balance, which icon would you set it too ie cloud, sun, shade, etc.. or do you set the temperature values yourself
Oh Sorry for late response =S Yeah one thing that may help, I'm not sure about the D90 but you may be able to boost ISO to like ISO16,000 so no matter how dark it is your camera is so sensitive to light you can see right through the ND fliter, the K-5 does it automatically so I'd say it's work manually at least for the D90. with white balance, I use CTE and manually manipulate the colour band based on that, your best bet is to go into the white balance area and take a sample shot, like a fully lit area, then just play with the sample shot, one time will be fine, remember, if you take your shot in RAW you can manipulate the white balance in your RAW development app, but it makes your life worlds easier if its pre adjusted.