The Sun - 26th Aug 2015

[David Smith]

Late gap as I got home from work, just enough time for a white light and a couple of quick Ca-K videos. Evenings getting shorter now so the Sun was hitting the roof tops by the time I finished up.

2 Pane full disk

20150826_CaK by David Smith, on Flickr

AR2403 @ 1500mm FL

20150826_AR2403_1.5x by David Smith, on Flickr

[Pete Presland]

Another super set of images some cracking detail.

[michael.h.f.wilkinson]

Superb set of images. Love the CaK particularly

[JamesF]

Indeed, you're producing some lovely CaK images.

James

[Tyson M]

That 120 ed is stopped down in aperture right? To 100mm with a coffee can? 

Lol I am looking at purchasing that same refractor for planetary and  solar some time 

[David Smith]

Thanks all for your kind comments.

To be honest I am surprised myself how "easy" I have found it to get good results in Ca-K. I read a lot of information before buying the module that said how "difficult" it was and how "seeing nearly always ruined the day" and that's why you don't see as many Ca-K images as you do H alpha and white light. True, I think I have been lucky with my Evostar 120 from a spherical abberation perspective, the body of opinion seems to be that many scopes simply cannot focus well at 393nm but fortunately mine seems ok. The beauty of Ca-K is there is no "sweet spot" to worry about, no "on-band / off-band" to worry about, no tuning to worry about and no Newton rings (at least, not in my setup), you just plug in the module and get going.

Suffice to say I am very happy with this particular purchase despite it being one of my largest (costliest) and scariest

The only down side is winter is on the way and I will be restricted to clear weekends only

That 120 ed is stopped down in aperture right? To 100mm with a coffee can? 

Lol I am looking at purchasing that same refractor for planetary and  solar some time 

Actually it's the 120 achro but yes, it is stopped down to ~100mm with a home made mask (coffee can and cereal box packet - true Blue Peter style )

[Space Cowboy]

Those Ca-k images or superb David!

[Lowjiber]

Those CaK images of 2403 are spectacular.  Nice Job!

Thanks for the share.

Clear Skies

[Tyson M]

I may copy your idea, I thought it was very clever. Cheers.