Here's the situation - I appear to get image degradation if I use TEC with my OSS DSI, it is stated on the relevant Yahoo group this can be caused by moisture in thr camera housing - and that the cure is to bake the camera in a dry (not gas) oven at about 120F (that is about 50C right?). Question is - has anyone at IIS done this and if yes how (temp is a bit low for a domestic oven and I really dont want to damage the camera)...
For something like a CCD camera I'd be pretty wary of putting it in any oven....
Can you not disassemble it and gently dry it out?
Maybe place it in a sealed box full of desicant - bags of silica gel used as moisture absorbers in various things. You can also get silica gel for reducing moisture in cupboards and wardrobes etc
An oven - I can see that ending in tears somehow!
too radical...that was my thinking too, then again - for dessicant to work would require disassembly, hardly any less radical. The heating is gentle - baking is a bit of an overstatement for 50C and this chap:
I sure wouldn't be putting the whole camera in the oven (whatever brand). But I susspect just like the SBIG's there must be a desiccant plug of some kind in there, I just hope they've made it removeable so you can recharge it?
I have to recharge mine on my SBIG occcasionally. It's quite a hot temp but would depend upon the composition of the plug in your particular camera I expect. And mine needs to be baked for a long time. I think it's about 3 hours at 180 degrees C. Googling "desiccant plug" provides infor relating to the SBIG stuff.
Perhaps worth understanding the distinction between camera housing and CCD housing too. There's usually a chamber surrounding the CCD and that's what the desiccant plug attaches to.
Whilst there is a desiccant plug on my SBIG ST7E, there is no desiccant plug on the Orion Star Shoot Deep Space as it really is a budget ccd camera.
In terms of should you?
Well, I plan to bake mine (as Craig Stark suggested on the Yahoo newsgroup), before I next use it, as the last time I had it out with the TEC powered on, I was getting lots of blue haloes around stars.
If the water can escape with baking ie evaporation there must be "gaps" in its construction - then the dessicant should be able to suck the moisture out through the same gaps without disassembly.... just a thought.....
I think the problem doesn't so much as lie in the temp of the circuitry, but any plastic components supporting... and how well regulated the temp in a domestic oven actually is, especially at such low temps - not much margin for catastrophe.....
If the water can escape with baking ie evaporation there must be "gaps" in its construction - then the dessicant should be able to suck the moisture out through the same gaps without disassembly.... just a thought......
I do not think so, as you heat the chamber the air will expand (Boyles law) and thus the moist air will flow out of the chamber, this reduces the moisture present by the same %age as the volume displaced (50% or more should be easy), once at the higher temp the difference in water vapour concentration between the chamber air and the oven air will allow diffusion processes to remove more water but this is also enhanced by the higher temp when compared to diffusion only for the dessicant only approach.
I had the same problem, got the same advice from the Orion starshoot yahoo group.I decided to take it back to Bintel who replaced the unit without a problem.Its got a one year warranty and it makes sense to make use of that
I have been considering making a Biltong drying box, (to make biltong of course), but I think an answer to your problem could be solved in much the same way. Here is a suggestion found on the www for making a dryer.
"Make your own Biltong Maker
Take a largish cardboard box and place a false bottom of cardboard about 15 cm from the bottom with a dozen ventilation holes, say 20mm diameter. Fix 2 light bulbs underneath this, ensuring they do not touch the cardboard surfaces. Fix a couple of steel or wood rods close to the top for hanging the Biltong. (or the camera) Make some ventilation holes in the lid and close. Switch on the light bulbs. The heat will rise to the top causing dry air to escape. Within a few days you have your Biltong!"
As all you want to do is dry the camera out very gently, this would be a (basically) cost free way of doing it, and you could test the temperature generated with say 2 x 60 watt bulbs, and use higher or lower wattage bulbs to reach your target.
If it doesn't work, you can always use the drier to make biltong, or you can eat the camera.
I have also attached a picture of a similar idea, also for biltong making, to show you what it looks like.
Some folks keep cameras in a small cupboard with a light on all the time, as the heat generated will maintain sufficiently low humidity to prevent the lenses from growing fungus.
Hi John, my 1.5 cents worth !
I'd probably throw a temp gauge in the jerky maker if it was me, you can get a bucket load of heat into a box with lightbulbs ! and you'd need to regulate it. Personally I'd dismantle it and play with a hair dryer and then fix a silica gell sachet into the unit. I've done it with my Meade DSI. For the amount of moisture it is likely to pull in the gel should only need changing every 18 months, mind you I found the gasket on my unit was pinched in the factory, so I made my own and replaced it, so I expect there should be little or no moisture getting in now. It may be something as simple as a dismantle and inspect to confirm the gaskets / o'rings are sound and then you don't have to bake it, baste it, char grill it or boil it
