Warning: Buying Older Astronomy Cameras

[great_bear]

(this is a follow-on from another thread, but I the information is important enough to warrant having a thread under a new title)

I recently tried to recommission an old SCB-4000 but upon testing it, I found that with sensitivity turned up, it was splattered all over with dead pixels - which I thought was either mishandling or age. However, when considering purchasing a replacement, I figured it was worth trying an inexpensive experiment first - since my wife suggested that I was unlikely to have mishandled my camera (she knows how obsessive and careful I am with my astronomy stuff).

So I found a brand-new SCB-2001 on ebay and purchased it for a few pounds. It's essentially the same model as the SCB-4000 except with a 1/3" sensor instead of a 1/2" sensor.

To my delight, it was unusable.

That may seem an odd thing to say, but that was the purpose of the experiment: What I found was that the brand-new, unused, but very old SCB-2001 had exactly the same quantity and distribution of dead pixels as my old SCB-4000. Clearly my wife's hypothesis was correct - that I did not cause the damage through mishandling - it was merely the sensor degrading with age - even on a camera which had never been used. This has saved me from being in the awkward position of spending a lot more money with the hassle of a (perhaps argumentative) product return process, and so it was well worth spending a few pounds on this simple experiment.

So the take-away for me here, is to not to purchase a second-hand astro camera if the model is more than a couple of years old - even if it is only lightly used.

As for the two SCB's that I've got I'll sell them off cheaply on ebay, with a note to the effect that it's only high-sensitivity astro use which they're unsuitable for; for lightweight basic CCTV duties on the default settings they work just fine.

[Astroscot2]

So the take-away for me here, is to not to purchase a second-hand astro camera if the model is more than a couple of years old - even if it is only lightly used.

 

My last astrocamera by Starlight express was over 7 years old, I did not notice any issues with the chip prior to selling, raw images were just as good as the day I bought it

I'm not sure your statement is correct for all astro cameras.

 

[tomato]

There must be hundreds if not thousands of dedicated Astro cameras out there which are greater than two years old, but I haven’t seen any reports on here which indicate the majority are now unusable for imaging. I have a an ASI120MC-s which is in a permanent AllSky camera, and after 12 months outside it is showing a lot of dead pixels in the daylight, but I wouldn’t say it was unusable once a Bad Pixel Map has been applied to the image.

[Stuart1971]

12 hours ago, great_bear said:

(this is a follow-on from another thread, but I the information is important enough to warrant having a thread under a new title)

I recently tried to recommission an old SCB-4000 but upon testing it, I found that with sensitivity turned up, it was splattered all over with dead pixels - which I thought was either mishandling or age. However, when considering purchasing a replacement, I figured it was worth trying an inexpensive experiment first - since my wife suggested that I was unlikely to have mishandled my camera (she knows how obsessive and careful I am with my astronomy stuff).

So I found a brand-new SCB-2001 on ebay and purchased it for a few pounds. It's essentially the same model as the SCB-4000 except with a 1/3" sensor instead of a 1/2" sensor.

To my delight, it was unusable.

That may seem an odd thing to say, but that was the purpose of the experiment: What I found was that the brand-new, unused, but very old SCB-2001 had exactly the same quantity and distribution of dead pixels as my old SCB-4000. Clearly my wife's hypothesis was correct - that I did not cause the damage through mishandling - it was merely the sensor degrading with age - even on a camera which had never been used. This has saved me from being in the awkward position of spending a lot more money with the hassle of a (perhaps argumentative) product return process, and so it was well worth spending a few pounds on this simple experiment.

So the take-away for me here, is to not to purchase a second-hand astro camera if the model is more than a couple of years old - even if it is only lightly used.

As for the two SCB's that I've got I'll sell them off cheaply on ebay, with a note to the effect that it's only high-sensitivity astro use which they're unsuitable for; for lightweight basic CCTV duties on the default settings they work just fine.

Totally disagree, over 95% of older Astro cameras are absolutely fine, I have owned 20 year old SX CCD cameras and were all excellent, obviously not as sensitive as modern day CMOS cameras, but certainly more than capable of the  had one bad experience and it’s a shame, but this is not at all typical…..👍🏼

[tomato]

Having read a bit further, I think the OP may be referring to these CCTV cameras specifically, rather than all dedicated Astro imaging cameras.

[great_bear]

5 hours ago, tomato said:

after 12 months outside it is showing a lot of dead pixels in the daylight, but I wouldn’t say it was unusable once a Bad Pixel Map has been applied to the image.

That’s the problem - these types of Samsung cameras are chosen for LIVE astro viewing (direct from the video output port) as the frame integration is done live by the camera itself - so nothing can be done about dead pixels.

This is clearly a sensor issue - and as such, if this is an ageing effect it would happen to any brand of camera that used these imaging sensors - it is not a Samsung specific part. 

- and since the issue is the same on used and unused units, ageing is not an unreasonable assumption. 
 

Glad to hear that this doesn’t affect all cameras - it would be interesting to hear from owners of these cameras or others with the same sensors, how they are holding up today. 

[tomato]

I’m presuming the sensor in my AllSky camera has deteriorated due to it being exposed to full on direct sunlight everyday, you wouldn’t normally subject an astro (or any other camera) to this level of radiation.

None of my astro cameras which are all older by a few years, exhibit anything like the same number of dead pixels.