Cannot fire shutter on d80

If you are using an older lens the aperture ring will be close to the camera body when the lens is on the camera. In order to set the aperture with a D80 and older lens you must set the aperture ring to "22" or the highest number on the aperture ring available. For newer lenses there is no aperture ring. You set the aperture by setting the dial on the top left of the D80 to "A" for Aperture Priority. You then set the aperture by rotating the front dial on the right side of the camera under the shutter release button. On older lenses, after setting the aperture ring to the highest number, you then set the aperture in the same manner.

failure of the aperture unit is the usual cause - usually the contacts for the phase switch have come loose from the gear. You can find info on this by searching for the problem on the internet, including how to repair it.

I think the aperture is not shutting down to the opening you set it to. In an SLR, the aperture is normally fully open for viewing through the lens. When you press the button, the mirror flips up and the aperture closes to the figure you have set, then the shutter fires. If you have set a daytime aperture and the aperture sticks, you get a wide open aperture and an overexposed shot, but at night, you have set an open or almost open aperture anyway.

It is possible that the shutter is the problem, but the aperture is more likely to go wrong in my experience. It only takes a drop of oil on the blades. There ought to be a button or lever to shut the aperture down for depth of field preview which you could use to test this, or just look in the lens when the shutter fires to see if the aperture closes.

the lens is broken

Seems like your problem on greyish/blurry viewfinder is caused by the camera getting water logged. Get your cam cleaned by Nikon.

The flashing red light usually happens if you have this indicator set in the camera. This may not necessarily be an error.. just a setting that you have put in place in your menu.

Unless you are using high-end Nikon Speedlights with camera and flash set for Auto FP High-Speed Sync, your top flash sync shutter speed on the D80 is 1/200 second. The black band you are seeing at faster shutter speeds is because the second curtain of the shutter begins to close before the first curtain reaches the fully-open position (which is when the flash fires). The higher the shutter speed, the shorter the gap between first and second curtains. To get full exposure with flash, there must be an instant when the shutter is fully open -- first curtain completed travel, second curtain not started yet.

"As the speed increases the final image should get lighter" applies to ISO speed. Higher shutter speeds mean less light reaching the sensor, but that's not the cause of the black bands.

You may be shooting auto and there is too much light. If you want to be sure you are shooting with 18mm @ f3.5 then shoot with aperture priority (the shutter speed will adjust automatically). Ususally at a wide focal length you would want a small aperature (smaller f-stop) so this should not really be a problem.

davidsucklin,
You can use the film lens with the D80, but it it not react to the same settings as it did with the film body, the multiplier factor for the focal length is going to be different and it may be stopped down a bit. When you are shooting in aperture mode are you adjusting your shutter and ISO? The camera and the lens have to be communicating the same info to one another inorder for it to work. First set the camera back to auto mode the check the shot to see the settings (f-stop, shutter speed) test them with different ISO's to see what the camera thinks the settings should be, then go back to manual on the camera and lens and try the shutter priority mode with the aperture ring set at the 2.8 to see if it works then change to Aperture mode with the same settings that can take the picture. If it doesn't work keep in mind som of the older D lenses will drop some functionality (like aperture) in certain configurations. You can verfify compatibilty of your specific lens on Nikon's support site.
randy320sgi

Try CUSTOM SETTINGS MENU 31. (turn off EXP. delay mode).

Do you mean the control panel on top or the big LCD on the back?

The display on top should be showing you stuff like the shutter speed and aperture as you take the picture.

The display on the back will not show you the picture while you're taking it. The D80 does not have a Live View capability.