PST issues

[Steve o]

Hi, Im new to this forum. Im looking  for advice on an old 2006 Coronada PST. We suspect at some  point during a group viewing  it was knocked  over as there were scuffs on the front lens shield. Since  then we struggle to see anything other  than sun spots no mater how  much tuning and focusing we do, no flares etc.  

Is there possibly anything we can do internally to check alignment's etc or is there any calibration centres  in the UK ?

Regards

 

Steve .

[Stu]

Hi Steve,

Welcome to the forum.

@Peter Drew and @Merlin66 are likely the two best to advise on these.

I wonder if somehow the tuning ring has become disengaged from the etalon if the tuning is not working correctly? Does the sun still appear sharp around the limb when in focus? If so that would imply no issues with focusing although you can open up the black box just to check that the focusing mechanism still works ok.

Hopefully Peter and/or Ken will be along soon with some help.

[Steve o]

Thanks Stu, Yes the focus is sharp and will run in and  out of focus smoothly. Yes it could  be  possible the tuner has become  detached as just the  other day I was looking a the new solar cycle sun spot and the  tuning didn't appear to change much on the new spot. No surface detail or prominences, just orange ball in HA.

[Stu]

7 minutes ago, Steve o said:

Thanks Stu, Yes the focus is sharp and will run in and  out of focus smoothly. Yes it could  be  possible the tuner has become  detached as just the  other day I was looking a the new solar cycle sun spot and the  tuning didn't appear to change much on the new spot. No surface detail or prominences, just orange ball in HA.

Good, so that’s focusing off the list!

So just to confirm, it worked fine, showing prominences and surface detail before being knocked over?

[Steve o]

Yes we were seeing other detail, its  been  a  while due to the minimum but I'm sure there were other subtle details we are missing, and seem to coincide with a group viewing of eclipse or transit.  

[Merlin66]

Steve,

The lack of detail while tuning could be a symptom that the etalon has become decontacted. This unfortunately can be a terminal issue......

If the etalon is damaged, you need expert assistance from Coronado/ Meade. I also believe Beloptic offer a repair service - seems to be around 270 Euro ( https://beloptik.de/en/etalon-repair-service/)

Without seeing the instrument first hand it's difficult to confirm, but dropping a PST (or any other solar Ha scope) can be fatal.

Ken

 

 

[Peter Drew]

Hello Steve, welcome to SGL.     Sorry you have to start with an unfortunate problem.  As Ken has said, a likely outcome is that the impact has decontacted the etalon plates.

These very high precision plates are kept together by molecular bonding of the material, no glue or clips, a sudden shock can break this bonding and it is extremely difficult to reset them without laboratory standard conditions, hence the high repair price.  Where in the UK are you based?   

[Steve o]

Thanks guys  for your input, I'm based  in Hull East Yorkshire. I'll consider the  options you've given.

 

Regards

 

Steve.