8 replies to this topic

[MHamburg]

I have an original Starlight Xpress Lodestar mono guide camera that has served me well until recently. I cannot get rid of what appears to be a cone of readout noise. I have made sure every glass surface is spotless. When I rotate the camera in the eyepiece holder the readout noise rotates with the barrel of the camera. The included photo was made with all external light blocked by lens caps with an exposure every 2 seconds. If no external light is getting through, can the problem be with the camera's electronics? I have already been in touch with Terry Platt at Starlight. Thanks for all and any replies.

Michael

[Jim Waters]

If nothing has changed in your setup it may be time to get another guider.

[italic]

Is it time to make a new dark library for PHD? Did you bump the gamma control slider?

[KLWalsh]

You say ‘The included photo was made with all external light blocked by lens caps…’
I’ve had the experience that some plastic lens caps that are black/opaque to my eye leak IR that can be detected by an unfiltered mono camera. Try taking some shots like the one you posted but with aluminum foil also wrapped around the lens cap. If you still see the same noise pattern than it’s likely in the camera.

[vidrazor]

A modern guide camera is not that expensive, and will have far more resolution and sensitivity.

[MHamburg]

Is it time to make a new dark library for PHD? Did you bump the gamma control slider?

I had the gamma control slider all the way to the right - the darkest possible.

Michael

[MHamburg]

You say ‘The included photo was made with all external light blocked by lens caps…’
I’ve had the experience that some plastic lens caps that are black/opaque to my eye leak IR that can be detected by an unfiltered mono camera. Try taking some shots like the one you posted but with aluminum foil also wrapped around the lens cap. If you still see the same noise pattern than it’s likely in the camera.

Interesting suggestion, but this has never before happened and the consensus appears to be that the camera is kaput.

Michael

[MHamburg]

If nothing has changed in your setup it may be time to get another guider.

I think you are right and so does my wife!

Michael

[KLWalsh]

I had a Meade DSI camera that had died.
The ‘image’ was just white noise.
I put the camera in the ‘fridge for a half hour and it then worked again for a few minutes, then began putting out white noise again.
I opened it up and found that the thermal grease between the back of the sensor and the heat sink was mostly gone. I got some thermal grease from where I work, applied a blob between the sensor and the heat sink, reassembled it, and the camera came back to life.