Search found 28899 matches

by marktownley
Fri Sep 25, 2020 11:05 am
Forum: Solar Scope Modifications
Topic: 127mm Meade Triplet Mod
Replies: 16
Views: 3499

Re: 127mm Meade Triplet Mod

Yup :)
by marktownley
Thu Sep 24, 2020 4:13 pm
Forum: This is SolarChat !!
Topic: Active region in CaK, September 22nd, 2020
Replies: 7
Views: 107

Re: Active region in CaK, September 22nd, 2020

Really impressive images Frank!
by marktownley
Thu Sep 24, 2020 4:00 pm
Forum: This is SolarChat !!
Topic: H-alpha Sun 2020-9-23
Replies: 14
Views: 166

Re: H-alpha Sun 2020-9-23

Very impressive image!
by marktownley
Thu Sep 24, 2020 3:54 pm
Forum: Commercial Solar Filters/Cameras/Hardware
Topic: SCT Celestron 9.25 for Solar Imaging
Replies: 1
Views: 54

Re: SCT Celestron 9.25 for Solar Imaging

Hi there and welcome to the forum.

Your c9 is f10 already, stopping it down is going to make it closer to f20/f30, so using the TZ4 in addition would put it around f80/f120, which, is way too high. Is the c9 your only scope or do you have a smaller refractor?
by marktownley
Thu Sep 24, 2020 3:50 pm
Forum: This is SolarChat !!
Topic: Quark Gemini - Dual Quark anyone using it?
Replies: 2
Views: 53

Re: Quark Gemini - Dual Quark anyone using it?

Nope sorry. I'm not aware of anyone here who uses one.
by marktownley
Tue Sep 22, 2020 5:36 am
Forum: This is SolarChat !!
Topic: Focal Reducer for ZWO ASI 178
Replies: 9
Views: 112

Re: Focal Reducer for ZWO ASI 178

Use a 0.5x reducer but reduce the spacing between it and the chip (short nosepiece on the camera), this will result in a reduction factor closer to the 0.8x you are after.
by marktownley
Tue Sep 22, 2020 5:34 am
Forum: This is SolarChat !!
Topic: Sept 20 Proms
Replies: 8
Views: 69

Re: Sept 20 Proms

Top proms! Well done on the SPoD!
by marktownley
Tue Sep 22, 2020 5:33 am
Forum: This is SolarChat !!
Topic: New AR today
Replies: 9
Views: 110

Re: New AR today

Good shot Rod! Nice surge.
by marktownley
Mon Sep 21, 2020 6:49 pm
Forum: This is SolarChat !!
Topic: September 21 2020 Observations
Replies: 6
Views: 44

Re: September 21 2020 Observations

Glad you had nice weather James, good report.
by marktownley
Mon Sep 21, 2020 6:48 pm
Forum: This is SolarChat !!
Topic: Full disk 21-09-2020
Replies: 6
Views: 65

Re: Full disk 21-09-2020

Nice disks there Rainer!
by marktownley
Mon Sep 21, 2020 6:47 pm
Forum: This is SolarChat !!
Topic: Quick PST images 21st September 2020
Replies: 7
Views: 64

Re: Quick PST images 21st September 2020

Great disks Alexandra!
by marktownley
Mon Sep 21, 2020 6:43 pm
Forum: This is SolarChat !!
Topic: Today's SUN (20200921) | NEW AR?
Replies: 10
Views: 123

Re: Today's SUN (20200921) | NEW AR?

Great images Pedro!
by marktownley
Mon Sep 21, 2020 6:41 pm
Forum: This is SolarChat !!
Topic: Monday Proms 21st Sept '20
Replies: 11
Views: 118

Re: Monday Proms 21st Sept '20

Top shots Stu, they came out well.
by marktownley
Mon Sep 21, 2020 5:26 pm
Forum: This is SolarChat !!
Topic: 2020-09-21 - HA prom
Replies: 7
Views: 103

Re: 2020-09-21 - HA prom

Looks good Jochen!
by marktownley
Mon Sep 21, 2020 5:26 pm
Forum: This is SolarChat !!
Topic: 21-9-2020 TODAY'S IMAGES
Replies: 8
Views: 75

Re: 21-9-2020 TODAY'S IMAGES

Good disks Terry!
by marktownley
Mon Sep 21, 2020 5:38 am
Forum: This is SolarChat !!
Topic: September 20 2020 Observations
Replies: 4
Views: 42

Re: September 20 2020 Observations

Thanks for the report James. The sun is quiet apart from a few proms.
by marktownley
Sun Sep 20, 2020 8:11 pm
Forum: This is SolarChat !!
Topic: 19/09/2020 Visual Report
Replies: 2
Views: 29

Re: 19/09/2020 Visual Report

Glad you got a view in Andrew!
by marktownley
Sun Sep 20, 2020 7:53 pm
Forum: This is SolarChat !!
Topic: H-Alpha and IR Cut or 12nm secondary filters
Replies: 10
Views: 127

Re: H-Alpha and IR Cut or 12nm secondary filters

Starry Jack wrote:
Sun Sep 20, 2020 2:03 pm
I had no considered putting one on the nose of the Quark.
Don't put it on the Quark nose, at least put it on the nose of the 2" diagonal, preferably well ahead of that with 2" extension tubes.
by marktownley
Sun Sep 20, 2020 7:47 pm
Forum: This is SolarChat !!
Topic: The Sun - 20th September 2020
Replies: 12
Views: 116

Re: The Sun - 20th September 2020

Impressive disks Dave!
by marktownley
Sun Sep 20, 2020 7:46 pm
Forum: This is SolarChat !!
Topic: Saturday Sun 19th Sept '20
Replies: 6
Views: 69

Re: Saturday Sun 19th Sept '20

Good job given the conditions Stu!
by marktownley
Sun Sep 20, 2020 9:46 am
Forum: Forum Support Issues
Topic: Where are my bookmarks?
Replies: 3
Views: 159

Re: Where are my bookmarks?

Nothing has changed as far as i'm aware. Maybe your cookies were cleared on your device? Have you had to log back into the forum recently?
by marktownley
Sun Sep 20, 2020 9:42 am
Forum: This is SolarChat !!
Topic: H-Alpha and IR Cut or 12nm secondary filters
Replies: 10
Views: 127

Re: H-Alpha and IR Cut or 12nm secondary filters

I'll have to check the light cone diameter before the backplate to avoid vignetting. It's a fairly simple calculation - free aperture of the filter (mm) x focal ratio = point ahead of focal point (mm) to position the filter. You wouldn't want to use the 'absolute' free aperture, leave a bit of play...
by marktownley
Sun Sep 20, 2020 9:39 am
Forum: This is SolarChat !!
Topic: H-Alpha and IR Cut or 12nm secondary filters
Replies: 10
Views: 127

Re: H-Alpha and IR Cut or 12nm secondary filters

When all the load is concentrated centrally on a 2" filter opposed to moving it higher in the light cone to use as much of the area of filter as possible the chances of wavefront error distortion is increased which then could translate as poorer image quality.
by marktownley
Sun Sep 20, 2020 7:48 am
Forum: Solar Scope Modifications
Topic: Replacing Lunt CaK BF with something better
Replies: 17
Views: 295

Re: Replacing Lunt CaK BF with something better

Interesting thread Raf! If I can throw something into the mix here too, sampling. Your camera has 2.4um pixels and so at 393nm (my rule of thumb, others might go for a higher multiplier) is that the pixel size x 5 should put you in the f-ratio ball park you need to be for ideal sampling. So, for the...