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I first started attempts with CCD imaging after seeing (and impulse buying!) a Meade Electronic Eyepiece at the Astrofest in London in early 2002.
This eyepiece immediately gave me black and white images through video output to either TV or to my laptop computer. I soon found I could capture, stack and edit images and video files. Now, not only did I have holiday snaps to bore my friends, I had astrosnaps!
I then found the QCUIAG group on the web and thought things could be much improved using a relatively cheap webcam (I did look at prices of 'proper' CCD imagers but..... sometime...) - and what's more I had an interesting project on my hands.
Hardware
The
pieces from the web that I read suggested that the Philips ToUcam range were
suitable for a first attempt so I purchased a Philips ToUcam Pro (model PCVC
740K) - features on the box promised: VGA video (640x480), USB, low light (1 lux),
snapshot @ 1280x960pixels, 24bit colour and support for Mac and PC.
The unit pops out of the box like a three-legged eager animal; then falls over...
I followed the installation instructions (do read instructions and do NOT rush off and plug unit into your PC USB port until the software CD is running and asks for it!) and all installed easily and in three minutes there I was in a little window grinning at the webcam!
Now to take the unit apart and turn the Webcam into an Astrocam....
The egg-shaped case comes apart easily - you will need small hex socket to remove the screw holding the legs on and the two screws holding board to the plastic back - I found one of the Meade sockets from my telescope did the job.
The
left hand image shows side of board with CCD, microphone and red LED (the small
white lump at the top of board). The right image shows reverse of the board with
USB lead.
The board is about 37 mm x 42 mm x 10 mm.
The first thing I did was to remove the microphone by using soldering iron to loosen the two pins holding the device to the board. The LED, which is very bright, took a bit of thinking about. Others say cover with tape etc. but in the end I took courage and just used brute strength and broke it off the board - it came off nice and clean leaving two locations where I can, one day, solder a lead to another LED external to the astrocam case. The board has two mounting holes clearly visible in the images.
To mount the astrocam to my telescope I chose to use a small plastic box with lid tightly secured with four screws. I had read somewhere that the black tubes containing 35mm film had an o/d of 1.25" and sure, I found one, and it slipped into eyepiece holder on the telescope. (I have later found that the 35mm film tubes have a slight taper - you should use the end near the base of tube as other end will not fit.) I cut the film tube off leaving base to a20mm length.
The
next task was to decide best position for board in the box and drill a hole
opposite the location of the CCD chip. A similar hole was drilled in the centre
of the base of 35mm tube. I then glued
the 35mm tube to the outside base of the box - not a good idea - it broke off
after several attempts with various adhesives - so back to three 6BA 1/4"
nuts and bolts to provide a secure fixing. A touch of black paint was added over
nuts and bolts to reduce any stray light.
Add a slot to secure the USB cable into the side of the case and all that
remained was to decide how to mount the board into the case. I did not have any
suitable circuit board mounting pillars so looked around for other ideas - in
the end I cut a slices from a small eraser 
and glued them to the inside
of the case and used the original hex screws to
secure the board after aligning board to centre of hole in the case. I was
worried that I would have to keep remounting board to get chip central, either I
was lucky or the diameter of the image produced by telescope is larger than the
chip, but it seems to work!
See right, my AstroCam mounted on ETX 70AT.
Below shows a picture of the AstroCam mounted on my LX90 using a Meade Flip-Mirror system which provides immediate parfocal switching of the telescope image through a flip mirror between the visual eyepiece and the AstroCam CCD image on the PC:
UPDATE
No longer do you have to have all the excitement and satisfaction of stripping the ToUcam webcam and re-assembling and mounting the circuit board to get you own astrocam - webcam mounting tubes are available from your telescope store!
These tubes just require you to unscrew the lens from the webcam; then screw in the 1.25" adaptor and you are away. I found that when I inserted the adaptor with the webcam attached into the telescope the result was nearly par-focal with my Meade 4000 eyepieces! Furthermore, the webcam adaptor is threaded to take filters!
Have a look at BC&F Astro Engineering UK or Steve Mogg USA for details.
I now plan to have a go at making changes to my original astrocam to allow long exposures - see QCUIAG group on the web.
Software
The software I am using with my AstroCam are
Vega
from Colin Bownes - click Vega dislay below to go to Colin's download page. [Apologies
- maybe this software is no longer available: I have failed with recent attempts to
find the Vega site - please let me know if you can locate it]
This program allows you to capture BMP, AVI and FIT files. It has lots of features and one special one that has helped me - FOCUS. Focus enlarges the CCD image to full screen to assist focus adjustment. Vega is Freeware and what's more Colin does reply to e-mails!
AstroStack
click AstroStack screen image below to go to download page.
AstroStack has some essential tools in order to load and combine a set of pictures (from an AVI video or a sequence of bitmaps) and make it into a detailed and noise free image.
Astrostack can, of course, be used with digital camera images - it has a nice feature of automatically aligning your multiple images.
Of course, all of the above is OK as long as Uncle Bill's operating system allows it!
I have had problems with applications finding the drivers to run my AstroCam, other Webcams and the Meade Electronic Eyepiece! (What's New, I hear you say!)
Vega uses 'Video for Windows' which should normally be sitting there waiting for your call, but sometimes seems lost.
I have had to remove all other 'image' devices and try to unload the hardware as well to get webcam to work. My advice is to try to only install and run with the devices you really want. I had a major problem after using a Creative Webcam on my laptop. Vega would not then see any other device. There were no options in the Vega drop-down list of 'Devices'.
Vega requires that you have 'Microsoft WDM Image Capture' in the Video Capture Devices section of Sounds and Multimedia Properties. I had to delete other entries here before Vega would recognise the AstroCam device.
Colin Bownes replied to my e-mail describing the situation:
to delete ALL the drivers, reboot the machine, then install the ones you need, with the one you need most being installed last (so that it overwrites any common dlls that are used by some drivers.This happens quite a lot. The only way to stop it that we have worked out is
Hope this helps.
Colin
This not only a Vega problem as I had same problem with AstroSnap - yet at the same time my Creative WebCam software would find any device I plugged into the USB port (Creative hardware or whatever)!
From desktop use Start/Settings/Control Panel/Sounds and Multimedia Devices/Devices/Video Capture Devices..
View some AstroCam images - click AstroCam Images