Saturday 5th December 2020

[Montana]

Some sunshine!!!! well bits of it anyway. I had a small blue patch and managed to catch the CaK through the PST with the Chameleon and then an hour later manged the DS Halpha PST.

Sun_115338_05_12_2020 by Alexandra Hart, on Flickr

Sun_115338_05_12_2020_ f colour by Alexandra Hart, on Flickr

20-12-05 13-22-50 by Alexandra Hart, on Flickr

2020-12-05 Chameleon 1-6x by Alexandra Hart, on Flickr

2020-12-05 Chameleon 1-6x f colour by Alexandra Hart, on Flickr

One question (and you know I won't act on it) but my CaK PST is getting very dark now. Originally back in 2009 I could image with a 2x Barlow in winter. Now I can barely get 1/19 second at prime focus. Which bit has likely gone wrong? I need to slowly digest and mull over the problem.

Alexandra

[dhkaiser]

Can't help with the CaK, plenty of detail in the Ha. Newton rings?

[solardave]

nice images Alexandra good job

[JochenM]

Nice set of images, Alexandra.

I'm not sure how a CaK PST is constructed exactly; but maybe some muck buildup on the lens inside the filter unit? Had something similar happen with my Lunt CaK module last year. Opened it up, quick clean and problem solved.

[Stardust5858]

Lovely captures. Thanks for sharing my birthday sun. It's cloudy here.

[mattwastell]

Hi Alexandra - glad you found some blue sky.
The prom disc looks great - a few ghostly proms.
I have a similar finding with my LS60 - I have had one blue filter replaced due to it 'fogging' up. In my last sessions I noticed that the camera needed a much higher exposure (the filter is fine) but during the course of the session it changed significantly & I had to wind the exposure down - atmospheric?

[ffellah]

Fabulous pics Alexandra !

Franco

[JohnW]

Nice set of pics Alexandra - glad to see you got some viewing in while the AR's are still there. Cheers, John W.

[DeepSolar64]

Why bless your little hart! You have gotten some sunshine! Nice images. I especially loved the colored CaK images and the limb prominence one.

James

[marktownley]

Hi Alexandra.

You caught both wavelengths well, it's nice to get some sunshine.

If your CaK exposures are so low it's because the filters have rusted. There are 2 sets of filters that rust in a CaK PST; one is in the eyepiece holder - see if it unscrews. The other is where the blue band meets the base of the gold tube - see if it unscrews. The good news is that the rusted filters can simply be replaced by a Baader K line, and the other bit of good news is that the all important CaK filter does not fail or degrade - it is a different type of filter than the ones that fail. The rust is just the same issue that happens with Ha blocking filters. The likely bad news will be access to the filters, and the tube / ep holder not being able to unscrew because of loctite in the threads. The ep holder you should do with a boa.

Have a go and see if it unscrews.

Mark

[yltansg]

Dear Alexandra,

Nice images from both PSTs. Your Chameleon is doing very well. Hope you resolve the CAK PST issue.

Alfred

[MapleRidge]

Great disks Alexandra

I am always impresses with your perseverance to image the low sun through the bedroom window

Hope that you can clean up the CaK base don Marks suggestions!

Brian

[Montana]

Thanks everyone

Problem one, the Newton's Rings with the Chameleon. With the very kind help from Brian Ritchie (Smerral) he pointed me to this plugin for Photoshop
http://ft.rognemedia.no/
Video tutorial https://www.youtube.com/watch?v=FDM4lEw ... e=youtu.be

and Wow!! the NRs be gone. It takes a little playing around to understand and experiment with what it is doing but I think this looks better
2020-12-05 Chameleon 1-6x PS a by Alexandra Hart, on Flickr

The second problem, the CaK PST
Thanks Mark, I knew you were going to say I needed to dismantle it. Apollo also agrees that the filters are rusting. I need to be brave one day and take it apart, I really didn't like the Halpha PST dismantling but at least I know now that the hairdryer works and is more gentle with the boa
I am currently suffering grief because it is like both you and Apollo have told me that my faithful friend has a terminal illness

Alexandra

[marktownley]

That pattern suppressor looks interesting - will have to explore...

[Carbon60]

Wow, that Plugin looks amazing. Nice job. Beautiful images, Alexandra.

I can’t speak about the CaK PST, but I dismantled my Lunt modules and cleaned off some sort of cloudy grime from all of the surfaces a few months ago. I haven’t checked to see if anything has reappeared, but your post has prompted me to take another look.

Stu.

[DeepSolar64]

I am a bit worried about my Coronado BF15s rusting. So far so good.

[rsfoto]

Hi Alexandra,

Excellent results.

[eroel]

Alexandra:
A nice session anyway, you got the Sun.
As for your question, I did change one rusted filter from my CaK PST (the one near the eyepiece of the PST). First I used a Baader K line filter, but now I use the Baader Venus filter and it is much brighter. This is the one I have in my CaK mod.+Best regards,
Eric.

[yltansg]

Thanks Alexandra.

Downloaded the pattern suppressor and will explore later.

Alfred

[Montana]

Eric, is that the 1.25" filter?

Alexandra

[marktownley]

Eric, is that the 1.25" filter?

Alexandra

https://www.365astronomy.com/Baader-U-F ... ished.html

I think I would avoid any purchases until you have a route forward - if you are not able to dissect the PST another approach is needed...