My nikon d3000 lens is saying it isn't attached when it is, i've tried cleaning it, taking it off and everything and nothing has worked. what do i do?

First, make sure that you have the right adapter to couple this lens to your Nikon. A universal adapter may actually fit and properly click into place but the electrical contacts may not match your Nikon. Make sure the electrical contacts on the adapter match the contacts on the camera body.

If they don't match, get an adapter specifically for Nikon and perhaps, specifically for your camera.

Once you have verified that it is a Nikon adapter, you need to make sure the electrical contacts between the adapter and the camera body are clean. Many people clean the contacts by holding the lens release button down and twisting the lens or in this case, the adapter, on and off ten or more times.

If neither of these options work you may need to contact Opteka, Nikon or both.

If you remove the back cover, there is a flexible circuit on the bottom left that attaches to the rear circuit board. Check to make sure that there are not cuts in the lands caused by impact pressing the flex into the back board components. This is a common problem with this model.

Note: replacing this calls for removal of the mirror box. Nikon stopped selling parts on July 13, 2012. You may be able to find it on Ebay.

Promaster makes many different lenses. Some of their older lenses do not have the electronics to communicate with newer digital cameras, and you have to shoot in Manual mode. Could you tell us which lens you're asking about?

I am assuming it is a TTL (Through The Lens) Viewfinder meaning a mirror, Prism and screen gives you the image. This is based on reality and not any settings. This question confuses me. If something gets in the way and the viewfinder darkens AND the image you take is dark this means there is something very wrong with the lens and possibly with the camera. The Viewfinder image is what bounces off a mirror and when you take the photo the mirror flips out of the way. What is left is the lens, some air space and the sensor. It may be that one of the aperture blades may be moving when it should not. I am close to saying send the lens in and ask for a quote..

Yes. Since the lens does not have the electronics necessary for focusing and metering, you just have to do everything manually. Set the camera's mode dial to M for manual. You can then set the aperture and shutter speed.

Try taking the lens off and remounting it.

Whatever you do, don't force it. Unlike your camera, which has just a 1 year factory warranty, Nikon lenses are warranted to be free from defects for 5 years; and is likely still under warranty.

Contact Nikon Service to have the lens properly serviced / repaired. Having it looked at by an unauthorized repairer or even "messing with it" yourself could void the warranty.

I hope this helps! Please rate my reply - thanks!

Clean the contacts on the camera body and the lens where they meet with a cotton swab lightly dampened with rubbing alcohol.

Remove the lens.Try cleaning the contacts on the camera body and lens where they meet with a cotton swab lightly dampened with rubbing alcohol.

1.the lens is not suitable for newer Nikon DSLR, e.g AI-Nikkor or PC
2.try to clean the mount part at the camera and at the lens with clean-dry cloth
3.probably there`s some malfuntions inside the camera, please refer to your Nikon retailer