modded video camera

[shirva]

Sorry darlin I'm sitting in yard at work waiting on him coming..are you bleeding

[shirva]

Maplins tomorrow for second fan..and build at work on Monday...Davy

[shirva]

this is the finished Samsung scb2000 mod...parts sourced from maplins,,, 2-40mm x 40mm 10mm width fans,1 chrome finger guard,1 micro flick switch. remove the auto iris fly lead from the front circuit board.....the first fan is mounted blowing cold air towards the rear of the sensor board it sits on the lower ribbon cable and under the front top casing screw and I have epoxy glued the top of the fan to the alloy casing at top casing screw.......the second fan is fitted under the top casing blowing cold air on to main camera board and has a chrome finger guard fitted to the outside of the top casing....the auto iris socket is removed from the top casing and a micro flick switch is fitted using a repair washer after to the inside and lock washer,spring washer and lock nut is fitted....locking at rear panel of camera below power point and to the right a space between both circuit boards a hole can be drilled for the cables from the fans to come through....davy

[Carl Reade]

Tidy job on the camera Davy, just need clear skies now!

[Steve_Max127]

Looking good Davy, are both fans wired to the switch? Lets hope you get some clear nights, nlooking forward to seeing some images.

[shirva]

Yes Steve ..switch is really just for testing the before and after on noise and amp glow...pretty pleased with the look of the mod now...still prob need to address the focussing probs I had previous. .still step in right direction. ..Davy

[johnno]

Davy, wont it be better for the fans to blow out . The front fan sucking the heat away from the sensor to wards the back were the top fan picks up this hot air and blows it out because heat rises.

[shirva]

testing of mod....using sharpcap and a usb video grabber here are my findings..................camera in a insulated shed ........camera fired up with blanking cap on lens....fan off ten minute run, camera was running at 28.5 fps... approx17000 frames .....734 frames dropped...................run two no cool down time.....fan on ten minute run no changes to camera settings.....camera running at 29.5 fps...17671 frames...322 frames dropped....................................run three no warm up or cool down of camera.......fan on ten minute run, camera now running at 30 fps....17992 frames ...0 frames dropped........................................................... i do not have any findings as yet,, that if i done three runs with the fan off i would have any different results from above,,,,, but i believe the camera getting run with the fan on has made these results accurate in my humble opinion...i have had a look at the video dark frames fan off and on and cant find any hot/dead pixels will attempt to stack and publish findings...low clouds here so no telescope testing tonight.......davy

[shirva]

duplicate post

[shirva]

hi johnno...i had thought of this, my modification has had my head buzzing hopefully this may give an insight to how and why i have done mod this way....original mod in my mind was to fit a heatsink under top casing to catch rising heat on outside above cut out of top casing i was fitting a peltier and heatsink with a fan...peltier blew out during testing and was rated to pulling six amps of juice...pretty hopeless for running from a power cell...ended up fitting fan only blowing down on to heatsink to make it a cold finger type...having looked at the data carl has been posting and some rethink i was going to give the peltier another go but more reading and thinking on this...when the hot air hits the cold from peltier there is the big chance of introducing moisture inside camera if board components were sealed you would then be insulating and creating more heat.....so being a mechanic i was thinking on a intercooler turbo arrangement type mod of forced air induction ...why try and remove heat when you can stop it being produced in first place....the dedicated astro cameras are peltier cooled to approx -30 this camera electronics cant go to that without causing thermal shock so this was best i could come up with keeping camera mod tidy and functional...feel free to try/change my mod or give opinions ...remember its only a fun hobby and hobbies are for fun and enjoyment....davy

[johnno]

Davy, I was also thinking about the peltier way, but it seems a biggish job to do, bought the peltier but decided not to do it. I can see were your coming from doing it something like a intercooler, but the hot air as nowhere to escape to unless you make holes for it to escape. then you might have other problems like you said that dust will get into the camera. I just did the one fan mod in the top casing blowing it out. I was thinking of getting one of them small digi temp gauges to fit the sensor inside to see what temp it was reaching inside.

[johnno]

I think we will have more problems with moisture and condensation in this country more than others , I've just been outside and already the car is covered with moisture unlike if you was in a warmer climate you wont be having this as much

[shirva]

hi johnno...correct in what you say about dust ect,,had a look for a filter but struggling for one for 40mm fan size....I had forgot to add to my post on mod I had drilled a 6mm hole at front of top casing to vent the air...it fires air out it big time...I can defo see the why folk want to suck the hot air out ...its very logical and was way I was doing my mod...if it dosent get hot in first place then no probs is my view, runs cold from start up...on the test results post I went from a hot un modded cam running 28.5 fps and dropping 700 odd frames to cooling a hot cam on second run halfing the dropped frames and increasing frame rate to 29.5 fps to third run now running cold at 30 fps and dropping no frames all done in a 35 min window....davy

[shirva]

hi johnno... was going to bring my fluke meter home to check temp but don't really think I need to...no looking for perfection so to speak original research done I found that somebody stated if you reduced temp 6% you will half the noise I think I may have done that with the last run with camera running at 30fps and dropping no frames ...cant ask for more I don't think....need some decent nights on scope for full testing...davy

[Carl Reade]

Hi, all after a lot of research I came across fans and blowers that are unbelievably small (the smallest is 8mm x 8mm x 3mm). They run on 3 Volts, not a major problem and I think looking at the circuit diagrams provided by Paul they should be able to run off the lens DC power.

I have ordered a 15 x 15 x 3mm (about 5 pence size) one to test placed next to the front board at the rear of the CCD so that the air is focused to the chip area. My theory is that such a small fan, which runs at 10,000 - 15,000 RPM will be able to deliver decent cooling at the hot target area without adding any weight and dragging in any unwanted dust etc anywhere near the chip face.

As soon as I have the results I will post either good or indifferent. I have added a link for everyone to have a look. Any thoughts welcome.

Cheers Carl

http://www.taiwantrade.com.tw/MAIN//resources/member/4645/productcatalog//26fcbbe3-94db-4a24-91c3-4f99e4f892b8_96_201100009338_L.jpg

[johnno]

Blimey Carl, never knew they made them that small, you'll have no trouble slotting that midget in.

I was thinking about sticking one of these on top with probe inside near the sensor.

http://www.ebay.co.u...=item2a2442483f

[Carl Reade]

Blimey Carl, never knew they made them that small, you'll have no trouble slotting that midget in.

I was thinking about sticking one of these on top with probe inside near the sensor.

http://www.ebay.co.u...=item2a2442483f

I could'nt believe it myself. The one thing I am lacking is a digital thermometer so at the moment I will have to test with live dark frames. They also do blowers so lots of options. Heres hoping for an even better result. A company called rapid sells them and Farnell.

Have looked at peltier cooling and there are just too many negatives, weight, current and moisture etc to justify it.

Cheers Carl

[shirva]

Created a monster. ..lol Davy

[shirva]

Johnno...I bought a volt /amp LCD from hk it was junk nowhere near accurate and the adjustment screw would not calibrate it...try one for tropical fish tank...Davy

[shirva]

Carl..what air displacement are midget fans producing. .I thought using bigger fan displacing more air over larger surface and keeping full board cool a better option. .can but try,, all a learning curve lol..weather stinking up here yet...Davy.

[Carl Reade]

Davy, the spec sheet states 8.75 L/Min, speed at 14,000 RPM. It certainly wont make icecream. My thinking is that due to its size I will be able to focus the air flow directly at the chip area compared to using a bigger fan, bit like a torch beam and a laser.

Results remain to be seen could be useless, a large fan may work a lot better. I await its arrival, I have my specialist mounting kit ready (Bluetac) lol.

[shirva]

Hope it works out..will take my meters home and test heat from camera mod on and off and can compare results. ....took stills from the video test and had no dead hot pixels that I could see ..done check in Photoshop seems ok....Davy

[shirva]

Aargh forgot meters..at work tomorrow. ..

Pick them up then..Davy

[shirva]

Update on temp readings from camera .....all internal readings done by a fluke 78 multimeter ...camera UN cooled..ambient temp 23c camera temp 24c.......fan on temp dropped 1c in 30 min....stripped camera and reversed the fans to blow hot air out....ambient temp 27.7c fan off camera temp 30c 30 min of testing ..fan on 10 min ..temp 27c.....conclusion. ..fan sucking hot air is best method but only reducing camera internal temp by 3c after 10 min ...leaving fan running to test over longer period.....Davy

[shirva]

Tested for over an hour did not reduce temp any better than 3c....where now I ask...back to drawing board ...Peltier time methinks. ...Davy