FDs in Ha and CaK 25th June 2022

[Carbon60]

Just a couple of disks from this morning.

I stopped down my 125 Tecnosky to 60 mm following a discussion with Mark for the B1800 Lunt CaK module. I had to remove the internal Omega filter from the B1800 module because the image was really unevenly illuminated. A bit more experimentation required to optimise.

20220625_CaK_FD_Mono by Stuart Green, on Flickr

20220625_CaK_FD_colour by Stuart Green, on Flickr

Ha FD using my Lunt 60

20220625_Ha_FD_Mono by Stuart Green, on Flickr

20220625_Ha_FD_colour by Stuart Green, on Flickr

Thanks for looking.

Stu.

[torsinadoc]

Very nice full discs. Thanks for sharing

Alan

[marktownley]

Nice disks there Stu, strange how illumination was uneven.

[Carbon60]

Hi Mark,
I think it’s the position/angle of the internal Omega filter. My guess is the higher focal ratio makes the setup more sensitive to angular misalignment if the filters are not exactly normal to the light cone. The Omega is only held in place with PTFE tape on the threads to make it fit.

Something to ‘fettle’.

Stu.

[rigel123]

Excellent disks Stu!

[arnedanielsen]

Really nice discs, Stu!

Thanks for sharing,
Arne

[Montana]

Breath taking views Stuart

Alexandra

[Carbon60]

Many thanks, Warren, Arne and Alexandra.

Stu.

[ffellah]

Lovely views of the sun from the UK, Stu. Very windy here, now I understand some of the challenges...

Franco

[RodAstro]

Nice images Stu

Just a tip for the Omega filters, they fit perfectly into the 1.25 plastic moon filter fittings that are supplied with scopes like cheap Celestrons.
You may need to protect the plastic though.

[RodAstro]

also sold as Skywatcher as well

Cheers Rod

[Carbon60]

Many thanks, Franco I hope you’re enjoying your vacation

Thanks for the tip, Rod.

Stu.