Omega CaK stack

[Merlin66]

First results with the Omega CaK stack.
The weather hasn't allowed me to test the Omega stack....
It's the <390nm UV block as a "mini erf", then the 80nm CaK followed by the 2A CaK.
Mounted on the TS102, Baader Herschel wedge (with 1.6ND filter).
Using the ASI 174MM.
(I've had to remove the tilter to gain focus...)
Well, today has thin high cloud, little wind, today's the day.....
Stacked in AS3!, some Registax 6 wavelets......

[GUS.K]

That's a great image Ken. The detail looks similar to what you get with a Lunt Cak filter (I think it's also a 2A)What's the price like compared to the Lunt Cak filter.

[Merlin66]

Gus,
i'll double check for you, but I think a couple of hundred $$$ all up.

[Atmos]

Really nice Ken, better than what I can get with my lowly PST :P
Detail and structure wise, what's the difference between Ha and CaK?

[Merlin66]

Thanks!,
Imaging in the light of CaK (3934A) actually shows the solar chromosphere at a different height from H alpha.

The H alpha (6563A) is visible from the photospheric surface (the "white light surface") up to around 1500Km - this shows the sunspots, plage, filaments, spicules and surrounding surface of hydrogen mottles.

At the Cak level >1500Km the image is dominated by the hydrogen flocculi - larger network of "supergranulation cells" with brighter flocculi areas around active regions. In CaK the sunspots are still visible as well as some filament type structure.....

I'm quite pleased with the outcome from the Omega filter stack - little or no vignetting, no major signs of ghosting and a bandwidth which looks similar to that achieved with the commercial Lunt CaK module.
Better seeing would help!!!

[Merlin66]

Gus,
Checked my files, the three Omega filters cost $375 all up.

[Derek Klepp]

A good result Ken.

[Merlin66]

Thanks Derek, appreciated.

[GUS.K]

Plus the wedge, still cheaper than the Lunt B600($1200), thanks Ken.

[Merlin66]

Yeah, but you already have the wedge for white light observing/ imaging ;-)

[Merlin66]

Also, the filter stack is based on 25mm diameter filters....
Anyway, I need to do more work on the image processing side - FireCap vs SharpCap, AS3! vs Registax6 vs imPPG......

[John W]

Interesting result Ken - well done for experimenting. Cheers, John W.

[Merlin66]

John,
Just waiting on better conditions to see how far we can go....