first light dissapointment

[geordie85]

I've finally managed to get out tonight and try my new (to me) Atik 383l that I got off astrobuysell.

I'm unsure whether I've been ripped off or maybe I've done something wrong.

All my subs have black lines running through them. I was using a Skywatcher 12V, 17AH power pack to only power my CCD 

Here is a quick stack.

 

Edit: they only seem to be on long subs. I've just checked a few of the 10 second subs I took whilst framing and there's no black lines in any of them

[wxsatuser]

Low voltage?

[Waldemar]

Yep, low voltage may be the problem. 17Ah is not that much for a camera that may use ± 3A when the TEC is working. on max capacity
Be sure your battery is fully charged.
What you see in your image may be the power drain peak when your TEC is switching on and off?
Did you try a mains connection with the adapter?

Second: what about your USB connection? dubbel shielded high quality cables? length of the cable? running next to a powercable? Induction and interference may be the problem too...

Most of the time the cables coming with cameras are not very high quality.

Waldemar

[geordie85]

Thanks for the suggestions.

It does seem to have only occurred when cooling was on. I was running at -20 and then at -10. The black banding seemed to be alot worse at -20.

I'm sure the power pack was fully charged but I'll put it on charge again today and test it out later on. I was using the leads that came with it.

If the problem still persists, does anyone have any ideas how I can power it? I was thinking about getting the mains supply from FLO but I'm unsure if it can be used outside because of dew.

[theastrodragon]

1 hour ago, geordie85 said:

Thanks for the suggestions.

It does seem to have only occurred when cooling was on. I was running at -20 and then at -10. The black banding seemed to be alot worse at -20.

I'm sure the power pack was fully charged but I'll put it on charge again today and test it out later on. I was using the leads that came with it.

If the problem still persists, does anyone have any ideas how I can power it? I was thinking about getting the mains supply from FLO but I'm unsure if it can be used outside because of dew.

I wouldn't worry too much about dew on a mains supply, they usually keep themselves warm enough.

Its surprising how much you can maltreat them - mines now rusty from years of getting wet, doesn't make any difference.

[RafalT73]

1 hour ago, geordie85 said:

...

It does seem to have only occurred when cooling was on. I was running at -20 and then at -10. The black banding seemed to be alot worse at -20...

Hi, I'm pretty sure that this is power supply problem. I am also user of ATIK 383L and I had a similar problem at the beginning (huge number of hot pixels and black banding - maybe not so many as in your case but still a lot). When you turned on cooling then voltage drops down because power consumption was high. In my case to over come this problem I bought XBox adapter (14A / 175 V) - POWERING The power is stable slightly above 12V (which is reall good for ATIK). Later on, I built  portable power box based on battery power converter and XBox adapter.

http://moje-nocne-niebo.blogspot.com/2016/01/zasilanie-terenowe-self-powered-setup.html

[Andy Mitchell]

Have you been careful to never let your pack become fully discharged? Standard lead acid batteries really hate that and will never hold a proper charge after.

I suspect a lot of astronomers packs are left in a dark corner over summer and are flat as a pancake when they come out from self discharge.

I've got the 7Ah skywatcher pack and it powers my HEQ5 plus an Atik One which also has TEC OK.

 

[geordie85]

I've only ever properly used it once since buying it. I charged it for a full 24 hours as that's what the instructions said. It was a couple months ago so I'm busy charging it now to see if it was due to power shortage 

[michael8554]

The mains power supply for this camera is rated at 2.5Amps.

Not sure how long your 17AH battery will supply 2.5Amps, it's nominally rated 17/12 = 1.4Amps

Michael

[geordie85]

An Update:-

So I had my power pack on charge near enough all day to make sure it had enough power for tonight. 

I set up and took a few test images whilst focusing at 60 second subs. On screen with the atik capture software there was no banding. "I've sorted it" I thought. Loaded the image into DSS and the banding was there still, even without having the cooling turned on.

I tried changing the save file from FITS to TIFFS, loaded the image into DSS and success, no banding. I turned cooling on to -10 and took another 60 second sub, again no banding.

So I'm now taking 300 second subs on NGC2244 at -10 and so far I'm getting no banding.

Looks like my laptop doesn't like FITS files. 

So if anyone else encounters banding with an atik 383l, try changing the save format to TIFF. It worked for me

[RafalT73]

That's good, means your camera is OK. Laptop or software are less problematic.