My manual focus keeps slipping...

When I am making long exposures (ok, only 30 seconds) for my astrophotography, I can hear a "tic, tic, tic...." and know that the image is being ruined by vibrations and the fact that the image will now be out of focus. The previous image can be in focus, and the next image after the ticking has stopped will be out of focus. I don't really know what to do to make the focus ring more stable. I have a kit lens, btw.

drevilsmom wrote in post #6984317
When I am making long exposures (ok, only 30 seconds) for my astrophotography, I can hear a "tic, tic, tic...." and know that the image is being ruined by vibrations and the fact that the image will now be out of focus. The previous image can be in focus, and the next image after the ticking has stopped will be out of focus. I don't really know what to do to make the focus ring more stable. I have a kit lens, btw.

What is causing the vibrations? Surely if you use a good tripod and a remote switch, and MLU, this shouldn't happen?

Kind regards, Wim

are you on manual focus, if it's on a tripod have you switched IS off ?

No, it is attached to a clock drive so I can track the stars. Even when it was on a tripod that was low to the ground, it would do it. Do I need to switch IS off? I admit that it is on. How would that help? I do have the MLU function on. I also have it on a 2 sec delay before it starts exposing.

Have alook at this post

http://forums.dpreview​.com …rum=1019&messag​e=28488980

don't know about clock drives

taking IS off shouldn't matter as the lens is supposed to detect when it's on a tripod...but the way i look at it is it can't hurt to turn it off

if you use Live view it's the same as MLU...i'm assuming your using live view to manual focus with the 10X zoom

also i'm a little lost what exactly is the "tic...tic...tic..."? where's it coming from ?

Thanks for the article, bikers1. I'll have to try that. DreDaze, I don't use live view to focus. I take a short exposure shot, usually around 5 seconds, and then adjust. The "tic" sound is coming from the camera. I thought it was coming from where it is mounted, as it seems like I cannot get a good, tight mount on my el cheapo tripod, but when I attached it to the clock drive, I know it is good and tight, and I listened really close, so that is why I suspect it is coming from the lens. The ticking is also not in a rhythm, either.

Manual mode, manual focus, IS off - the lens shouldn't be doing anything - therefore, no noise or change in focus.

gasrocks, I've done everything BUT the IS off, so I'm betting that may be my culprit. Weather permitting tonight, I'm going to find out!

Thanks for all that helped. It was the IS. I was able to take several shots before the clouds rolled in, and I didn't have a bit of trouble. Thank you, thank you, thank you!!!!