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A Colour CCD Camera for less than £75
The Bolton Group
Is it possible - a colour CCD Camera for under £75? Read on! The advent of the Colour Quickcam CCD Camera (now marketed by Logitech) for under £75 means that the answer is YES. Not only can it take still colour images at up to 640 x 480 resolution, it is brilliant at the live display of the telescope image to an audience. At last several people can "look" through a telescope simultaneously. It can also record videos - imagine panning across the Moon and replaying it indoors! |
 Ganymede, Europa, Io and Jupiter
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Introduction
First things first - the Quickcam camera is an excellent introduction to CCD imaging but it cannot compare with a £2000 SBIG! What it does better is the live display of images, and in colour too. Its refresh/display rate is fantastic so images appear with very little delay. It is great for the Moon and planets, but its lack of cooling means that long exposures are compromised - only bright deep sky objects such as the Orion Nebula are within range. |
 The Colour Quickcam
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The Camera is cheap because it does not have its own power supply and it must be connected to a computer (via keyboard connector and parallel printer port) to work.
It therefore requires a computer right next to the telescope.
To use it for astronomical work we will have to open it, voiding the warranty, and remove its lens.
Our telescope will then become a new high quality telephoto lens for it.
Having said all that, it will provide the best fun you will ever have for only £75($100).
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 Rehoused camera - note 1.25 inch fitting
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Construction
As mentioned above all we have to do is remove the lens and provide some means of attaching the camera to your telescope. The key to opening the camera is the little hole, usually found under a label on the bottom of the camera. By pushing in a small screwdriver a clip can be depressed and the two halves forced apart with a bigger screwdriver. First a word of warning, because of static it is easy to destroy the camera's electronics just by touching it. We advise wearing rubber gloves when handling it, so as to insulate yourself. Once opened the lens can be screwed out revealing a glass window with the CCD underneath. We now have two options - either make a new housing for the camera or reassemble minus the lens. The former can be as low-tech as a plastic aerosol cap, the latter would need some method of attaching the camera-ball to a focuser. For us however, Gerald machined an aluminium housing with a 1.25 inch nose to fit standard focusers. Whatever method the cord needs securely holding as any pull on it could disconnect the top circuit board. Gerald did it with a split cover plate that traps the cable grommet.
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 Jupiter 1998
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Imaging
This is the exciting bit! First a word of encouragement. We were successfully displaying live images and saving them on our first night! The pictures shown left of Jupiter and Saturn were taken on that first night, before we really understood how to get the best out of it. The Moon shots we took a couple of days later when seeing was atrocious. We should improve on them next time around. The camera comes with software called QuictPict which as well as being the picture taking method also provides continuous live images. It is brilliant for viewing the Moon and the planets and showing them to visitors. The three of us were mesmerised by Saturn and its rings at our first attempt. It provides all the usual camera controls, even bulb for time expousres. For image display and taking, it is best to switch off the autobrightness control and adjust the brightness manually to get the exposure right. Because of rapid image display focusing is easy and quick. For the planets we found 320x240 with zoom on to give the best display. A three times tele-convertor boosted image size of the planets but makes pointing harder - you will need a good finder for centring on the chip. For the Moon prime focus should give enough magnification. Image processing has to be done in another package, such as Paintshop. However don't expect miracles - individual image quality is not high but can be much improved by adding several images together. That's about it really - it is very simple and great fun! |
Moon just before full - mosaic of 4 images with 6 inch Schmidt/Newtonian
Stop Press: Logitech, who have taken over from Connectix in marketing the cameras,
have upgraded it to the Quickcam Pro with 30 bit colour (1024 levels per colout as opposed to 256),
but the price has gone up. |
