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cwgeib
December 17, 2009, 15:29:18
Last night I set up to do some flexure testing of my rig in the Dayton, OH area. Outside temperature when I started was about 27F. I was unable to complete my testing as the temperature dropped to around 23F and my
DFK31AU03.AS camera which I use as a guide camera started to act erratically. I use PHD guiding and normally don't experience too many issues. Last night I'd get 2 to 10 1.5-second frames then a period of time (random up to 30 seconds or so) of absolutely nothing. Or I'd get some garbage signal that would crash PHD. I switched over to the IC software that came with my DFK and experienced the same very erratic behavior. Upon checking, I discovered the data sheet online states a max temperature operating range of -5C to 45C. Turns out -5C is 23F which is what my camera was experiencing. My question is, how do others keep the camera warm when atmospheric temperatures have dropped below the operating temperature of the camera? Have you used dew heater strips? Thanks in advance.

Chris Geib
Dayton, OH

cwgeib
December 20, 2009, 19:48:57
How do you operate these Imaging Source cameras below 23 F? Thanks!:at-wits-end:

Stefan Geissler
December 21, 2009, 11:17:51
Chris,

it seems, there are not many people using this camera at -5C (23F). Unfortunately I have no idea how to operate this camera at this temperature. Heating may is an idea.

creeker
December 21, 2009, 15:28:18
Chris,

it seems, there are not many people using this camera at -5C (23F). Unfortunately I have no idea how to operate this camera at this temperature. Heating may is an idea.

Hello
This is very disturbing to me. It appears I should have studied the specifications closer before I purchased my DBK 31AU03.AS. Not functioning below 23℉ would seem to make this camera worthless for most of the Northern parts of North America & Europe during the winter months. I can't believe that IS designed a camera for astronomical use, that can't be used below 23℉. Most of the cameras on the market today are cooled or are able to be cooled to sub zero temperatures for better performance. This January Mars will be favorable for imageing, and in the
colder climates, this camera can not be used. My club members will be laughing at me when I tell them, I'll have to try and heat my camera or use it in the summer. Expecting an astronomical camera to function below 23℉ is not being unreasonable. Many CCD camera users live in areas that have night time temperatures that fall below 23℉, (including Germany). IS advertising should make these facts more known. I have been preparing an observatory to use my camera for planet imageing, I guess I will be purchacing a new camera. Not from IS
Ed

creeker
December 23, 2009, 17:20:54
Hello Stefan
I am working on a solution for this problem. I have made a dew heater to fit the camera. This heater will run off a pulsed controller so as to regulate the temperature. I made a close fitting box to cover the dew heater and camera. This box is constructed from an insulating material used in homes.
It is like "bubble pack" used for shipping, but the two outer layers are aluminized. It is about 6mm in thickness and the air spaces are about 6mm. A probe from a digital thermometer will be in the box, taped to the rear of the camera, to monitor the temperature of the camera housing. If this is successful, I will use a Kendricks dew controler, with it's own temperature sensor, that can be set to turn on an off at a temperature above an ambrient setting. After the holidays I will keep you posted as to my success. Seasons greetings and have a good holiday
Ed
P.S.
Here in Connecticut at noon, it is -4℃, 5:00AM it was -12℃ Astronomers are a crazy bunch. :-) Saturday we got 30cm of snow, my daughter lives little SW of Washington DC got 60cm.

Kokatha man
December 24, 2009, 02:03:31
Hi Ed.....I'm sure a heater could be utilized to raise the temp to within the working range (not that down here in Oz we have to worry about those sorts of temperatures....!)

FYI this camera WASN"T designed as an astro-camera by IS.....they just happen to be good video cams for said application!:-)

Regards, Darryl.

JohnM
December 24, 2009, 02:43:15
I've used my DMK down to some fairly low temps, but evidently not low enough to see any effects.
Here where I am, we have plenty of way below zero Fahrenheit this time of year.
Next time it quits snowing and we get some clear skies, I'll do some runs to try and see just where mine starts to show effects of cold.
I imagine something like a Kendrick heater strip could be used to get the camera electronics warmed up just enough to function, but not warm enough to start adding noise.

JohnM
December 27, 2009, 17:34:32
This morning we had favorable conditions to image the Sun in Ha.
So, I set up at a temp of +10F. I thought the DMK21AUO4 was going to work at that temp. I got 2 AVIs and then IC Capture locked up on the 3rd one.
Hmm? I have a Kendrick heater on now and I'll wait awhile and see if after the camera has warmed up it begins to work again.

astrogerard
January 10, 2010, 21:11:55
I have used the dmk31af03 at -10 celcius without any problems.
Problems started after upgrading to IC Capture 2.1. Lockups and crashed occurred. Reverting back to version 2.0 solved this problem.

My conclusion is:
- The DMK can operate succesfully at -10 celcius or warmer
- Version 2.1 of IC Capture is crap

Gerard

Emil
January 10, 2010, 23:47:06
Are you sure it is a camera isue, and not for example a wiring problem??

I can use my DMK21AU at about -8c without any problems (it can't get much colder here). At those temperatures, the usb-cable is a lot stiffer though (but I use a pretty thick one to avoid cable issues).

Stefan Geissler
January 11, 2010, 08:46:48
Problems started after upgrading to IC Capture 2.1. Lockups and crashed occurred. Reverting back to version 2.0 solved this problem.

I agree, this is annoying and should not happen. However, we use this version on many different computers without any problems. Also in different OS starting at XP and ending at 7 64 bit. Since I do not know, which OS and computer model you use, I can not help. Also it may is helpful to know, what you have done. There as an IC Capture version, that locks up when an image should be saved using the FileSave dialog of Windows. This has been fixed.
However, for using the FireWire and USB cameras, there is no difference between 2.0 and 2.1.

astrogerard
January 11, 2010, 18:52:40
However, for using the FireWire and USB cameras, there is no difference between 2.0 and 2.1.

Well the difference on my system is huge. With V2.1, which was downloaded between xmas and new year, I wasn't able to save more than one or two avi's until the program crashes. Reverting back to 2.0 instantly solved this problem.

As I understand there's no functional difference I'll stick to 2.0 for the time being.

FYI some requested details are:
Camera: DMK31AF03 12 v externally powered via split-cable
OS: Windows XP Pro SP3
Computer: HP nc8430
FireWire Interface: onboard Texas Intruments OHCI IEEE 1394 Host Controller
Driver version: 5.1.2535.0


My apologies for the other readers. My intention is not to hijack this thread.
I did respond to the temperature question as the DMK's aren't that afraid of the cold.

Gerard

Stefan Geissler
January 12, 2010, 09:45:59
Hi Gerad,

no problem hijacking the thread. Do you have an idea, how big your captured AVI files were, or how long did you capture? I guess, you used the Y800 uncompressed codec setting.

I will try to reproduce the problem.

Stefan Geissler
January 12, 2010, 12:23:33
Gerard,

I created a new thread regarding the AVI capture problem: http://www.theimagingsourceforums.com/showthread.php?p=32935

bdeclerc
January 16, 2010, 20:16:51
I can confirm that I've had no problems operating DMK camera's at temperatures as low as -10C (last year, even a DMK31 at -15C).

Besides the software-discussion, you might also look into some other components that might cause problems. Most USB-cables are not designed to operate at low temperatures, so that could be the cause, connectors will also shrink when cold, which might cause connection-instability.

The DMK camera's also pull quite a lot of current out of the USB-port, more than most devices (though still within spec), so if the drop in temperature causes issues with power supply that could also result in some negative effects - at lower framerates the camera uses less power, so setting it to 3.75fps might show better stability.

cwgeib
March 10, 2010, 16:06:26
Last night I set up to do some flexure testing of my rig in the Dayton, OH area. Outside temperature when I started was about 27F. I was unable to complete my testing as the temperature dropped to around 23F and my
DFK31AU03.AS camera which I use as a guide camera started to act erratically. I use PHD guiding and normally don't experience too many issues. Last night I'd get 2 to 10 1.5-second frames then a period of time (random up to 30 seconds or so) of absolutely nothing. Or I'd get some garbage signal that would crash PHD. I switched over to the IC software that came with my DFK and experienced the same very erratic behavior. Upon checking, I discovered the data sheet online states a max temperature operating range of -5C to 45C. Turns out -5C is 23F which is what my camera was experiencing. My question is, how do others keep the camera warm when atmospheric temperatures have dropped below the operating temperature of the camera? Have you used dew heater strips? Thanks in advance.

Chris Geib
Dayton, OH

Just thought I'd offer an update. I bought an extra AstroZap heater strip and wrapped the DFK31AU03.AS in it the other night. Temperature was around
20F and I had no problems running the camera with heat applied.