red saturation on a nikon 18-200 right side during long exposure

[86reddawg]

I'm new to the world of SLRs and am having some issues with long exposure (4+ minutes) images. I recently bought a Nikon 18-200 3.5-5.6 lens to use on my D5000.

My first experience with a long exposure left some red saturation on the right and upper corners of my pic. I attributed the redness to the moon as the moonlight was hitting the tree...



I noticed it again the other day and decided to take a long exposure with the lens cap and the eyepeice cap on, and I'm getting an image like this:



Am I doing something stupid? Have a setting way out of whack? or is there something wrong with this lens? For what it's worth, the kit lens 18-55mm does not have this problem.

 

[astrograph]

did you use a red flashlight behind the camera?

When doing long exposure photography light reaching the sensor through the viewfinder might be an issue. Be sure to cover the viewfinder when doing this kind of work.

regards,

Philipp

--
Philipp Salzgeber
http://www.salzgeber.at

 

[Leon Obers]

For what it's worth, the kit lens 18-55mm does not have this problem.

Strange, first I should think to limitations by the sensor and electronical capabilities itself. I have seen this in past with more early sensor designs. But as you are writing it is not there using the 15-55mm kitlens, I should say the lens have a strange leakage of light.

Try some other lenses too under the same conditions and settings, and see what you get.

--
Leon Obers

 

[sganger]

Do a forum or google search on the subject. Reviewers and Nikon themselves very rarely (if ever) discuss it, but it's actually a very common problem with digital sensors. The D80 (which I have) is notorious for having a problem with amp glow.

It should be apparent in a long exposure lens cap test like the one you did no matter what lens you use, are you sure it doesn't happen with the 18-55? I suppose there's also the possibility in that case that your 18-200 has a light leak around the mount, but I still don't think that would cause a red glow like that.
--
http://www.flickr.com/photos/_sam
http://poeticdiscord.deviantart.com

 

[Mikael Ejberg Pedersen]

At first look there's written "amp glow" all over it, BUT I don't think so. Only 4 minutes on a new generation chip shouldn't be so bad. Then I saw you said 18-200, and I vaguely remember an old discussion some time ago:

I believe it is the VR mechanism inside the lens, that is emitting some IR light. Yes, even if you have turned VR off. I think the solution was to turn off both VR and autofocus, but I'll see if I can find the discussion again.

 

[Mikael Ejberg Pedersen]

I think the discussion I remember might start here:
http://forums.dpreview.com/forums/read.asp?forum=1039&message=26783756

It filled up to the max allowed messages, and then continued in a new thread. Unfortunately, I can't find that one.

 

[C_4]

If I recall, this is not "amp glow" from the camera sensor, but some sort of IR or heat source inside the 18-200 VR lens.. Turning off the VR function apparently "fixes" this..

 

[86reddawg]

Thanks, that link seems to be exactly the problem I'm running into.