4 replies to this topic

[JimTheEngineer]

I need some help. Just received a new Lunt50 and had it out at the worst time of day 5pm. Seeing was bad, FTF is not here yet, etc.. However, I have what may be newton rings but not really sure. There is this curved swath of on band with 2 sides that look off band. How do I fix this - camera tilter?

Also, I notice that I will have to focus AND adjust etalon to get the prominences to look better. Is there a good video on how to process these two images seperate and then merge together?

Was very impressed with the views using an eyepiece. Was extremely disappointed with the helical focuser. Wish I hadn’t wasted $97 on the helical focuser.

Edited by JimTheEngineer, 27 May 2024 - 07:54 PM.

[rigel123]

The right side is off band and not in the sweet spot (Jacquinot Spot).  It looks like the best tuning is moving towards that area from the left, so you either need to work on the tuning more or move the disk in your FOV more to the left if there is room to do that.  The sweet spot is not always centered on the chip of the camera and you may have to move the disk around a bit to find where the best tuning lands on the chip.

[gstrumol]

I'm sorry, but what day was this taken?

[JimTheEngineer]

Here is the gong image.

 

i don’t have very much room. It is a P1 Saturn with a 2.5x powermate. It was a quick end of day setup and didn’t have time to fiddle. But I think I have the idea to move the image to the circular spot and tune there.

 

Question - does tilting the camera help?

 

Can the internal etalon be “tilted”. It’s brand new - does something like this get better/worse over time. Also, how should I “put away” the etalon - burp the etalon and then just put the cap a few turn with minimal pressure or “pressurized” from last position. Maybe the pressure leaks off anyway?

Edited by JimTheEngineer, 28 May 2024 - 12:22 AM.

[rigel123]

Here is the gong image.

 

i don’t have very much room. It is a P1 Saturn with a 2.5x powermate. It was a quick end of day setup and didn’t have time to fiddle. But I think I have the idea to move the image to the circular spot and tune there.

 

Question - does tilting the camera help?

 

Can the internal etalon be “tilted”. It’s brand new - does something like this get better/worse over time. Also, how should I “put away” the etalon - burp the etalon and then just put the cap a few turn with minimal pressure or “pressurized” from last position. Maybe the pressure leaks off anyway?

Different folks do different things with their PT scopes.  Some relieve the pressure each time, others leave it.  If I owned a PT scope I would probably relieve the pressure each time and figure out how many turns it typically takes to bring it all on band.  If tuning with the camera attached I’d try it without the Barlow and see how large the sweet spot is.  If you can get the full disk tuned and within the sweet spot then it should be good when you add the Barlow, but if it isn’t right in the center of the FOV then you may have issues ever getting the full disk in the sweet spot with the Barlow in place.  It takes practice for sure!  I don’t believe you can add tilt to the etalon but you could try tilting the camera a bit to see if moving the disk that way makes any improvements.