Odd artifacts with new ATIK 383L+

[TrickySpot]

Hi Guys,

Just got a ATIK 383L+, took some test shots last night, pushing the camera all the way to 20 degrees below 0 and I got what I thought is ice in the photo...is this possible??? See attached!

Thanks!

[ncjunk]

Yes it may be ice.

You can end up with moisture inside the camera and when it is taken to a low temperature ice forms.

If you google atik 383 ice you get a couple of hits suggesting leaving the camera for a couple of days in a zip lock bag with dissicant. Most cameras also come with a dessicant filled tube that attaches to the camera to remove moisture.

Also cool down in 5 deg steps and dont go all the way in one go. I always prefer ramping down or up the cooling in steps to avoid any thermal shock.

You should be able to sort it out.

Sent from my GT-I9003 using Tapatalk 2

[Gina]

Yes, that certainly looks like ice. I got the same effect in my DSLR sensor when super-cooling with too much moisture in the camera. Much of my work on the DSLR cooling project involved methods of getting the humidity down low enough.

[perfrej]

I have to agree - you're all frosted up. I run my CCDs at -30°C or -35°C all the time and have never seen a frosted glass before. Thanks for the peek

/per

[ollypenrice]

Most if not all of the newer Atiks have a removable dessicant plug. It's a black slot head screwdiver thing at right angles to the optical axis near the front. Just take it out, dry it thouroughly, dry the camera thoroughly, and reassemble. I don't think the 383 has a heated chip window like the 4000 and 11000 but check this in the manual. Activating the chip window heater if you have one can't be done from Artemis Capture. You have to go into EEPROM to do it but the manual is clear on this.

Atik deal with temp and internal dew control very well indeed, at least on the last few cameras of theirs that I've had.

Olly

[RAC]

Just swap out the dessicant by following Atiks advice and all will be good. Another good idea it when cooling it down just go to about -5 and leave it there for a few minutes befor going to say -25. I've had to change the dessicant on mine once after buying it but after that its been perfect.

If you don't have spare dessicant then just pop the dessicant out of the camera then put the dessicant in the oven at about 180degC for and hour or so, pull it out let it cool for a minute or two the put it in the camera.

[NickK]

Yup the christmas card look is ice. Once the desiccant is changed it will disappear.

As others have said - you can regenerate the desiccant by putting in an oven.

[Kbramley]

I had icing on my 383L+ too, I emailed the chaps at Atik and they posted me 6 fresh dissicant tabs, great service, especially considering I had bought the camera second hand. I now keep the camera in a sealed lunchbox with a bag of dessicant just to keep it extra dry.

[Velvet]

some nice pretty ice crystals there dessicant for a few days.... should dry it all out

velvet

[Chris Rowland]

As everyone says, ice. One thing I've found is that if you leave the camera cooled for half an hour or so the ice seems to go away. I guess that what happens is that it sublimes and freezes out on somewhere that's colder. Atik seem pretty good at supplying desiccant tablets and they are pretty easy to change.

Chris

[Nathan_Pembs]

Also cool down in 5 deg steps and dont go all the way in one go. I always prefer ramping down or up the cooling in steps to avoid any thermal shock.

May be a daft question, but was is thermal shock exactly? Just bought an Atik too (314E) but the "warm up" function doesn't seem to do anything, the fan keeps going. I don't like the idea of just turning off the cam if I could damage it.

[ncjunk]

I believe its when different materials expand or contract at different rates causing failure or fatigue over time.

It shouldn"t be an issue with astro cameras, i've not heard of any failures, but i prefer to gradually change the temp anyway to reduce any posible stress on the materials...the poor little things!

Sent from my GT-I9003 using Tapatalk 2

[NickK]

The warm up function tells the camera to slowly cycle up the temperature.

The watercooled 11000 is an example where the temperature delta can be substantial and warming up too quickly could cause stresses that break the glass/sensor.

[Gina]

Yes, I provided a slow warm-up on my Peltier cooled 1100D DSLR with warming up from -15C taking over an hour. I always use the warm up feature on my CCD cameras.

[ollypenrice]

The warm up function doesn't affect the fan, which keeps going. Maybe if you don't have the two stage Peltier it doesn't do anything, I don't know. On our large format Atiks you click Warm Up and it says 'Warming up'. Usually the temp just starts to rise slowly for a while then the status changes to 'off.' Sometimes it acts the goat and goes colder before going warmer!

Olly

[TrickySpot]

May be a daft question, but was is thermal shock exactly? Just bought an Atik too (314E) but the "warm up" function doesn't seem to do anything, the fan keeps going. I don't like the idea of just turning off the cam if I could damage it.

Hi Nathan, you have my 314E :-)

I never had any problems like this with the 314, hence my surprise with the 383 on the first night! I store mine in a zip lock bag now with 100 small silica gel bags.....but I can also image very successfully at 1 degree, with dark frames.

[Nathan_Pembs]

Hey Martin, good to see you on here Last night was clear, so the 314E got first light (for me anyway) Totally different to using a DSLR, got to get used to setting the exposure etc. Also what image on the screen in Artemis is a rough copy of the "actual" image taken. A great camera!

[TrickySpot]

Hey Martin, good to see you on here Last night was clear, so the 314E got first light (for me anyway) Totally different to using a DSLR, got to get used to setting the exposure etc. Also what image on the screen in Artemis is a rough copy of the "actual" image taken. A great camera!

Nathan, not sure I understand your question correctly? I think you may be thinking the same thing I thought when I first used Artemis, but I can't put it into words.....below is what I do, it works for me, but

I guess all I can say is, I stretch the image until I'm happy then save it still as a FITS. The stretch info gets saved into the FITS file I think, but the actual raw data is not modified. After a while you'll get a feeling for whether the single shot is good/bad for a whole imaging session. And then shoot away until you get tired or the sun comes up. Then you'll be left with a whole lot (say 10 x 10 min) of alrighty looking photos. I don't know what you going to use to stack, I use MaximDL, but Deep Sky Stacker seems good and is free. And when you stack the magic happens, one really good image should come out of all the alrighty ones. Then I do a final stretch, balancing between noise and detail, export to JPG and switch to Photoshop for final editing. Noel Carboni's actions for photoshop are a blessing, they fix up a lot of my mistakes! My very very rough website shows how single frames become better images when stacked.

http://www.neutronbridge.com/astro.htm

This might all be old news to you, just ignore me then!

[Nathan_Pembs]

I've just been used to using Backyard EOS with a DSLR, where what you see on screen is what you get, compared to the grainy "live view" on Artemis. I use DSS to stack the FITS, which then gives you a final TIF file to edit in Photoshop

[tferrari]

I had a similar issue. Using new desiccant pellets with my 383L+ did not solve the frost issue during rapid cooling to -20C. However, as per ATIK's advice, heating the tablets in the oven at 200C for 90 minutes, cooling them to room temp and leaving them in camera for 24 hours solved the frost issue when rapidly cooling. Zero frost occurs now.

One risk with frost appearing on the sensor is that it has the possibility of leaving behind traces of thermal compound.

If you have any issues, just contact ATIK. They're pretty good.

[RAC]

I had a similar issue. Using new desiccant pellets with my 383L+ did not solve the frost issue during rapid cooling to -20C. However, as per ATIK's advice, heating the tablets in the oven at 200C for 90 minutes, cooling them to room temp and leaving them in camera for 24 hours solved the frost issue when rapidly cooling. Zero frost occurs now.

One risk with frost appearing on the sensor is that it has the possibility of leaving behind traces of thermal compound.

If you have any issues, just contact ATIK. They're pretty good.

Yep after having oven dried desiccant pellets in my 383L I just got straight to -25 and see no problems. Makes me think the desiccant pellets aren't perfectly dry to start with even out of the packet.

[pubquiz]

I had the same thing (though not quite as much ice) happen on my QHY8....as well as the desiccant advice ....I now use an attached tube for it full of the little orange balls type of desiccant

I also use a 2" dew strap wrapped around the nosepiece ...QHY do a heated window add on but I have found the dew strap seems to work.

Tom

[Herrman]

Hi,

My 383L also suffers from icing, I've found that the problem goes away once the camera's been running at set temperature for 20 mins or so. Swapping the desiccant pellet for a dried one also helps.

Regards, Herrman

[TrickySpot]

Thanks for all the answers! I now take it down to 1 degree and take a 5 min exposure, then drop down the rest with no ice at all. The heat from the 5 min exposure clears the water vapor on the sensor. I just hope that storing it with desiccant bags will eventually remove the moisture all together. Built in desiccant tabs (x3) have been replaced and baked, but don't do the trick alone, maybe they also need time to work fully.

Cheers,

Martin