To summarize results of my and Patrick's tests, I think the answer for the "cheap meteor cam" what has been done by the Croatian Meteor Group. Report 2nd Year of Croatian meteor network (2009) http://www.imo.net/imc2009/pdf/segon_andreic_korlevic_imc2009.pdf Slide 3 Describes using the Sony EX View HAD modified to disable the automatic gain control to reach down to 3 or 4 mag with modification by "Filip Lolic". They are using a $270 base camera from Supercircuits based on the Sony ExView HAD chip - http://www.supercircuits.com/Security-Cameras/Dome-Security-Cameras/CD42IRHR This uses the same chip that Patrick has in his Supercircuits IR camera for $85 and that I have in a raw camera board received yesterday - Supercircuits PC402UXP. The problem is that the Sony ExView HAD chip has automatic gain control, automatic brightness and backlighting compensation forced on. The AGC feature has to be disconnected for the Sony ExView HAD chip to function as an all sky cam. After the AGC on the camera board is disabled, it should reach down to mag 3. I have emailed the Croatian Meteor Group asking for a set of instructions on modifying the camera board. Possible solutions are, if the Croatian Meteor Group does not respond are: 1) Is there anyone in the group who is an electronics wiz or has experience in with the old Quickcam modifications (that turned the Quickcam into a lunar planetary camera). 2) Is there anyone in the group who is Croatian? The Croatian Meteor Group might be more willing to respond if a native speaker contacted them. 3) Perhaps the club through some of Patrick's contacts at the UofU could ask the UofU electrical engineering department to work out the modification. This is the kind of project that an electrical engineering student could probably tackle with ease. Patrick did not get below mag 1.5 in his test with Supercircuits PC88WR. Last night I tried with the Supercircuits PC402UXP Super Low Light raw camera camera board with a 90 deg. While the AGC is enabled and cut-off the camera's response, I boosted the gain on my laptop's video board to the max. This gives a grainy image. The TLM was around 2.0 with Orion's belt at the eastern horizon just above city lights. http://www.slas.us/gallery2/main.php?g2_itemId=2736 I'll have to retry this from Little Mtn the next time clouds clear out where there is less light pollution. If you search the web for "Sony ExView HAD" you can find any number of more expensive security cameras that have AGC and Backlighting cutout buttons - but they cost more money - http://www.alibaba.com/product-gs/251834984/1_3_Sony_Super_HAD_CCD.html For example, there is a microscopy camera that has the AGC override and a USB laptop connection built-in - but again at a price - http://www.ptgrey.com/products/chameleon/Chameleon_datasheet.pdf This Chinese direct company seems to have the lowest priced housings with the Sony IR chip in them - http://www.inesun.com/cate-597.html In summary, test moved forward to the sticking point of finding some wiring instructions for disconnecting the AGC, backlighting, white-balance switches on the Supercircuits board with the Sony ExView HAD chip. Personally, I am not electronic educated, can use soldering iron and have built a few circuits out the basic Forest Mims books. Clear Skies - Kurt P.S. - Patrick, if in your wanderings in other newsgroups, you run across wiring instructions - specifically for the Supercircuits PC402UXP board - to disconnect the AGC, please let me know. I found one sheet of instructions for the ExView chip, but the camera board was different.
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Canopus56