Atik 460ex problems - any suggestions

[old_eyes]

Hi,

My secondhand Atik 460ex mono camera has behaved impeccably for a long time.

Suddenly a couple of weeks ago it went weird, having problems downloading and showing dark halos around stars.

I replaced the USB cable with another I had spare (only a cheap one) and tried again tonight. I am still seeing the same effects.

I wonder if anyone recognises this

This is a 60 second exposure taken with my usual Voyager configuration. A cropped section at 1:1 just STFed in Pixinsight.

I tried the same exposure using Atik's Artemis capture software, just in case there was anything weird going on with Voyager.

I also used NINA with the same results.

I know the images are somewhat out of focus, but the autofocus routines in Voyager and NINA took one look at this, and said - Nah! No usable stars.

It could be a usb cable issue and I am waiting on new Lindy Chromo cables from FLO and will test those as soon as they are here, but a bad cable has previously resulted in only partial downloads, never these curious dark rings.

I am asking Atik what they think, but just on the off change someone instantly recognises the issue, I thought I would ask here as well.

old_eyes

[carastro]

I have 3 Atik460EXs and never seen this.  

Only time I have seen holes in the stars (but not these weird blackish rings) was when I was out of focus.  

I am no technical Buff, but what scope are you using?  Maybe that might help some-one else to answer your question.

One other thought, are these Single exposures or stacked subs.  I found DSS introduced weird stacking artifacts if I had the cosmetic tab ticked.

Carole 

 

Edited February 25, 2023 by carastro

[old_eyes]

1 hour ago, carastro said:

I have 3 Atik460EXs and never seen this.  

Only time I have seen holes in the stars (but not these weird blackish rings) was when I was out of focus.  

I am no technical Buff, but what scope are you using?  Maybe that might help some-oine else to answer your question.

One other thought, are these Single exposures of stacked subs.  I found DSS introduced weird stacking artifacts if I had the cosmetic tab ticked.

Carole 

 

Thanks Carole.

These are single subs - to get the 'raw' data with minimal post processing. No calibration of any sort, no stacking.

Scope is an Esprit 120. I don't think it can be optical as the black points read zero. Not low , zero, total black. AN optical defect would not produce this sudden jump to zero. Out of focus stars the same. You get a smooth gradient as the 'doughnut' forms. The profile of the stars looks hideous. Sudden jumps between signal and no signal.

Baffled, but hoping for someone to say - "yep, I know what this is!"

[carastro]

I have asked a couple of knowledgeable people on my Whatsapp group and got the following replies:

1. Looks like a dewy sensor

2. Looks like classic flexure plus out of focus plus cloud or dew as ****** says

HTH

Carole 

[fwm891]

I've had something similar in PI when using a luminance mask and switching back-n-forth between stars and background applying different stretches, looks much the same but not on single subs...

[wesdon1]

12 hours ago, old_eyes said:

Hi,

My secondhand Atik 460ex mono camera has behaved impeccably for a long time.

Suddenly a couple of weeks ago it went weird, having problems downloading and showing dark halos around stars.

I replaced the USB cable with another I had spare (only a cheap one) and tried again tonight. I am still seeing the same effects.

I wonder if anyone recognises this

This is a 60 second exposure taken with my usual Voyager configuration. A cropped section at 1:1 just STFed in Pixinsight.

I tried the same exposure using Atik's Artemis capture software, just in case there was anything weird going on with Voyager.

I also used NINA with the same results.

I know the images are somewhat out of focus, but the autofocus routines in Voyager and NINA took one look at this, and said - Nah! No usable stars.

It could be a usb cable issue and I am waiting on new Lindy Chromo cables from FLO and will test those as soon as they are here, but a bad cable has previously resulted in only partial downloads, never these curious dark rings.

I am asking Atik what they think, but just on the off change someone instantly recognises the issue, I thought I would ask here as well.

old_eyes

I would suggest you clean the camera sensor, and also get a qualified electrician to test all the electronic components inside the camera. Just one single capacitor or mosfet being faulty will cause corrupted data and cause havoc with your cameras electronics. Remember your camera is exposed to extremes in temperatures, humidity, and dew, etc so water could easily accumulate on your electronic components, causing short circuits etc. Plus you have the regular heat expansion, then cooling contraction, of electronic components, which over time, causes tiny stress fractures and ultimately failure of said components. So all other causes being eliminated, I would suggest you get the electronics fully tested, and see if that is where the problem lies. Ultimately though, I am hopeful on your behalf that the cameras manufacturers will know exactly what is causing the problems and suggest a solution. Best of luck, please let us know how you get on, thanks.

[carastro]

Sounds like getting advice from Atik would be a good idea.  I know they don't make this camera any more, but they might still do servicing/repairs.  I have found them good in the past.

Carole 

[newbie alert]

Indeed that's very odd, I've got a problem with the data board on my 460 which needs a trip to Portugal soon

Before you go too in-depth I'd certainly eliminate the data cable, check the power supply and also I'd plug the data cable straight into the laptop rather than use a hub if you use one

 

[old_eyes]

11 hours ago, carastro said:

I have asked a couple of knowledgeable people on my Whatsapp group and got the following replies:

1. Looks like a dewy sensor

2. Looks like classic flexure plus out of focus plus cloud or dew as ****** says

HTH

Carole 

Hi Carole. Found some guidance on the Atik site for drying out a camera and regenerating the desiccant. Trying that now. If the recommend the process for users it can’t be too risky.

[carastro]

Yes l would definitely change the dessicant.  I have a dehumidifier in the obsy and put the camera near that when l had to change it but l must say my artefacts looked a little different to yours when  l had to change mine.  
 

i think l put the dessicant in a bag hanging on the radiator for a few days to dry it out.  
 

Hope it works. 
 

Carole

[old_eyes]

Carole,

Just a quick question. How many desiccant tablets were in your 460ex? When I opened mine there was a single tablet that fell out very easily, but under that is another white surface that I first thought might be a wedged tablet, but now I think looks a slightly different texture and could be a barrier membrane.

My observatory is not suitable for a dehumidifier. The main construction is corrugated steel and I went with  plenty of ventilation to prevent excessive condensation. It has worked well. In over two years operation I have only had two episodes of significant condensation. However, it means that a dehumidifier would be attempting to dehumidify the local atmosphere.

Might need to think about taking the camera off the rig when I am expecting it not be used for extended periods.

[david_taurus83]

The 460 has 1 tablet and a mesh barrier behind it to prevent ingress of dirt and dust while changing it.

If you take some bias frames now what is the lowest reported ADU value? At -10°C my old 460 had a minimum bias ADU of 163, in other words the offset value. Should never be 0.

 

[ollypenrice]

The speckling in the stellar cores is new to me and I've seen dewy sensors, cloud, and out-of-focus subs hundreds of times. I would certainly swap the power supply and cables, as newby alert suggests, and eliminate any third party bits like hubs. If you do send it back to Rui Tripa in Portugal you'll be in good hands, though. He's a gentleman. 

Olly

Edited February 26, 2023 by ollypenrice
typo

[Magnum]

My zwo 533 does something similar if i cool the sensor too fast, zwo say that it happens du to ice crystals forming i micro voids within the sensor around some pixels, and can be a sign the desiccant needs re charging. Ive seen over a dozen other reports of this on the zwo FB group. Ive found if i cool mine slower in 5 degree stages it prevents it from happening. Though in each case it was random pixels not stellar cores, but it could still be something similar happening.

im attaching an image from my cam with and without the issue

 
Ive never seen it on a CCD sensor before but fortunately its much simpler to remove the desiccant on Atiks than it is on ZWO, so i would give that a go, out the tabs in the micro for 2 mins then replace and leave for several hours before testing it. 
A more conclusive test would be to take an image with the cooler off first.

Lee

 

Edited February 26, 2023 by Magnum

[old_eyes]

16 hours ago, Magnum said:

My zwo 533 does something similar if i cool the sensor too fast, zwo say that it happens du to ice crystals forming i micro voids within the sensor around some pixels, and can be a sign the desiccant needs re charging. Ive seen over a dozen other reports of this on the zwo FB group. Ive found if i cool mine slower in 5 degree stages it prevents it from happening. Though in each case it was random pixels not stellar cores, but it could still be something similar happening.

The bits you circled certainly look superficially like some of the defects I am seeing. Something to bear in mind. However, Atik have come back and said they are puzzled and asked for faulty subs, which I have just sent them.

This feels like one of those journeys, gradually eliminating possibilities, rather than a jump to a solution. 😟

[carastro]

If Atik are puzzled, no wonder we are too!!!

Carole

[andrew s]

Have you checked that the power to the 460ex is clean both via USB and power?

Noisy DC could play havoc with the chip.

Regards Andrew 

[old_eyes]

48 minutes ago, andrew s said:

Have you checked that the power to the 460ex is clean both via USB and power?

Noisy DC could play havoc with the chip.

Regards Andrew 

Waiting on new cables to check. And I will of course check with no USB hub, and alternative power supply only for the camera.

[old_eyes]

UPDATE.

So none of the obvious things worked . Went through the drying and recharging the  desiccant protocol, alternative power supply, new USB cable, and direct connection to a separate laptop bypassing the hub and my pier mounted computer. 

Atik could not think of anything else to try so off it goes to them for (hopefully) repair in Portugal.

All I have to do now is navigate it through the customs system - the forms look horrendous and I could be liable for import duty both ways from what I can tell. Thank you Brexit!

[newbie alert]

On 09/03/2023 at 17:10, old_eyes said:

All I have to do now is navigate it through the customs system - the forms look horrendous and I could be liable for import duty both ways from what I can tell. Thank you Brexit!

Shouldnt be, that's what the documentation is for, you're not buying a new item, it's going for repair.... 

Edited April 11, 2023 by newbie alert
Damn phone