CaK filter

[aramitsharma]

Hi anyone having any experience using this filter along with the solar film on the front objective?

 

https://www.altairastro.com/altair-nuv-7nm-125-filter-6910-p.asp

[Merlin66]

Sounds very much like the Baader K-line version (8nm).

Should work well with a Herschel wedge or the recommended ND3.8 film.

 

[Nigella Bryant]

Yes does sound similar to the baader k-line filter. Even though it' says CaK it's to broad a wavelength at 7nm so will only show more contrast in the white light spectrum. Nothing wrong with that, I use the baader k-line filter for white light imaging. 

Recently imaged yesterday using it with a Hershel wedge and an 80ed refractor. 

[aramitsharma]

2 hours ago, Nigella Bryant said:

Yes does sound similar to the baader k-line filter. Even though it' says CaK it's to broad a wavelength at 7nm so will only show more contrast in the white light spectrum. Nothing wrong with that, I use the baader k-line filter for white light imaging. 

Recently imaged yesterday using it with a Hershel wedge and an 80ed refractor. 

Looks interesting... so not strictly as good as dedicated CaK, but still good...

[Nigella Bryant]

8 hours ago, aramitsharma said:

Looks interesting... so not strictly as good as dedicated CaK, but still good...

No not even close to a dedicated CaK filter. Attached recent comparison from the 14th. 

[Pete Presland]

Excellent example of the difference Nigella between the filters. I thought about one a few few years back, but i didn't think it was worth the investment. I would love a Ca-K scope though 🙂