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audia3td
February 10, 2015, 06:43:38
I tried to capture images with my ccd mono camera (usb) dmk 21au618.as connected to my telescope.
I pointed the telescope manually to Jupiter, got a nice minuscule view of Jupiter and its satellites through the Barlow piece and then I attached the ccd camera, fired the ic capture software, and all I got was a noisy black screen.
What am I doing wrong?
I tried to test the ccd camera in daylight, but I am not seeing anything understandable to the eye (is that normal for ccd cameras, or I have a defective camera?).
I went back to the IC Capture software and enabled the focus and zoom toolbar. To my despair the focus is not enabled. I am attaching the kind of image I am getting from my camera under room lighting. I am baffled, do I have a bricked camera or a defective brain?1752
Thank you for your help.

Michael Kirmse
February 10, 2015, 13:52:13
Hello,

First of all, your camera works fine, don't worry.

The camera itself does not have a lens of any kind to focus the light, thus testing it without the telescope will just result in the gray picture you are seeing.
The focus and zoom toolbar in IC Capture do not work for the same reason, as they are meant to control an automatic lens that is built into some of our cameras.

My first guess for why you just get a noisy, black screen with the telescope is that the cameras automatics are enabled.
When the automatic for exposure is enabled, the camera will not expose the sensor below the limits of the chosen framerate. By default, the dmk 21au618.as is most likely set to 60fps, which would only allow an exposure time of 1/60 second. That is most likely far too short to get a usable image from the telescope.
The gain automatic then tries to amplify the image in order to get a usable picture. This adds the noise, but is probably not enough.

In order to see something, I recommend to go to the Properties menu (right click the live video in IC Capture to get to it) and deactivate the automatic exposure and gain. Then set longer exposure times, until you can see an image. You may want to experiment with the gain as well, as it will help to achieve higher framerates, but be aware that any gain you add will also introduce more noise to the image.

audia3td
February 11, 2015, 01:47:59
Thank you for your reply, Michael! I played with the camera in my backyard, and managed to capture the first images. However it seems I have a few black spots on the image, please see the pic below. Does this indicate a defective camera? 1753

Stefan Geissler
February 11, 2015, 10:25:22
The black spots are dust on the sensor. Clean the sensor. In the FAQ you find some advises:
http://www.theimagingsourceforums.com/faq.php?faq=ic_camerahandling#faq_ic_cleaningsenso r

Stefan Geissler
February 11, 2015, 10:25:22
The black spots are dust on the sensor. Clean the sensor. In the FAQ you find some advises:
http://www.theimagingsourceforums.com/faq.php?faq=ic_camerahandling#faq_ic_cleaningsenso r

audia3td
February 11, 2015, 20:11:19
The black spots are dust on the sensor. Clean the sensor. In the FAQ you find some advises:
http://www.theimagingsourceforums.com/faq.php?faq=ic_camerahandling#faq_ic_cleaningsenso r

Thank you, Stefan! Indeed that was the case. It's tough to be a newbie...