Search found 3142 matches

by Merlin66
Mon Oct 22, 2018 3:21 am
Forum: This is SolarChat !!
Topic: ZWO ASI290MM is too slow in the FireCapture V2.6.08
Replies: 9
Views: 183

Re: ZWO ASI290MM is too slow in the FireCapture V2.6.08

Valery,
What’s the difference working with neutral gamma (50) and using unity gain and then altering the exposure value to give a good histogram?
by Merlin66
Sun Oct 21, 2018 8:44 pm
Forum: Commercial Solar Filters/Cameras/Hardware
Topic: BF30 ITF replacement
Replies: 7
Views: 187

Re: BF30 ITF replacement

I’ve mentioned previously, but repeat my myself again. Why do we think blocking IR beyond 1400nm is an important issue in solar filter design? This region is heat not light and well beyond the sensitivity of the eye or current imaging sensors. I accept that extended and prolonged exposure to IR can ...
by Merlin66
Fri Oct 12, 2018 8:25 pm
Forum: Solar Astronomy Shop and Swap
Topic: "Astronomie Solaire" - New (French) book on Solar Observation now available
Replies: 16
Views: 391

Re: "Astronomie Solaire" - New (French) book on Solar Observation now available

Christian,
Looks good!
Maybe you can include some information on the Spectroheliograph in the next edition ;-)
by Merlin66
Mon Oct 01, 2018 10:49 am
Forum: This is SolarChat !!
Topic: H-alpha 30092018, first light asi290mm
Replies: 23
Views: 456

Re: H-alpha 30092018, first light asi290mm

Using a Baader D-ERF up front and a secondary mini ERF another Baader ERF I think gives more “protection “ than the original blue glass filter element.
by Merlin66
Mon Oct 01, 2018 6:13 am
Forum: This is SolarChat !!
Topic: H-alpha 30092018, first light asi290mm
Replies: 23
Views: 456

Re: H-alpha 30092018, first light asi290mm

Lou,
On both the ASI 174MM and the ASI 160MM, I work at zero gamma (=50) with Firecapture. Adjust the ROI to give the best coverage and then adjust the Gain to give a good histogram....seems to work for me....
by Merlin66
Sun Sep 23, 2018 10:30 pm
Forum: Solar Scope Modifications
Topic: Improvements to your PST!
Replies: 0
Views: 132

Improvements to your PST!

Sylvain Weiller, well known for his excellent images with the PST, has fitted his PST with a x1.5 photographic converter, which he claims has increased the focal length from 400mm to 600mm and gives better definition and resolution. Interesting!!! http://sweiller.free.fr/PST/indexPST.html Note: the ...
by Merlin66
Sun Sep 23, 2018 10:26 pm
Forum: Solar Scope Modifications
Topic: Replacing the Rusted BF30 Filter
Replies: 56
Views: 2769

Re: Replacing the Rusted BF30 Filter

Ronatu,
It's very rare that the final sorting/blocking filter fails...usually the ITF goes first.
Do you have a "failed" BF?? If so can you upload an image of it.
by Merlin66
Sat Sep 22, 2018 8:54 am
Forum: Commercial Solar Filters/Cameras/Hardware
Topic: ASI 174MM and Firecapture - endless issues - looking for alternatives!
Replies: 5
Views: 884

Re: ASI 174MM and Firecapture - endless issues - looking for alternatives!

+1 from me.
I’m running an ASI 174mm using FireCapture on a Win10 MSI laptop - USB3, SSD drive
No issues, no drama.
by Merlin66
Mon Sep 17, 2018 3:24 am
Forum: Solar Reference Library
Topic: Surface contrast in CaK for various filter bandpasses.
Replies: 19
Views: 670

Re: Surface contrast in CaK for various filter bandpasses.

Peter,
I’ve sent you an email.
Ken
by Merlin66
Sat Sep 15, 2018 11:13 pm
Forum: Solar Reference Library
Topic: Surface contrast in CaK for various filter bandpasses.
Replies: 19
Views: 670

Re: Surface contrast in CaK for various filter bandpasses.

Eric, The digital spectroheliograph (SHG) that Peter (and others) use is not a visual spectrohelioscope (SHS) as used by Fred. Think of it as a second generation SHG making use of software to separate and re-combine the target spectral line to form a detailed image. The basic design is well within t...
by Merlin66
Sun Sep 09, 2018 10:16 pm
Forum: Solar Scope Modifications
Topic: Narrowest 393.37 ever by Apollo Lasky
Replies: 206
Views: 6559

Re: 393.4 bp0.1 - yes it does exist.

Skybender,
I think you miss-read my message...there was no intention of inferring you or the others are not capable of setting up filters.
I was suggesting, we as amateur solar observers, should have access to a capable spectrograph to allow us to confirm our own set-ups.
by Merlin66
Sun Sep 09, 2018 7:04 am
Forum: Solar Scope Modifications
Topic: Narrowest 393.37 ever by Apollo Lasky
Replies: 206
Views: 6559

Re: 393.4 bp0.1 - yes it does exist.

Guys, You are confirming my thoughts and experience with filters and etalons..... You really need to have a spectrograph to allow accurate measurement of CWL and transmission curves. I can test any filter/ filter combo with a resolution (as measured) <0.02A across the whole solar spectrum (370-8000A...
by Merlin66
Sat Sep 01, 2018 5:00 am
Forum: This is SolarChat !!
Topic: SolarMax 60 II vs, Daystar SS60-DS
Replies: 8
Views: 404

Re: SolarMax 60 II vs, Daystar SS60-DS

Pau,
The Daystar offering seems to be their Quark Chromo mounted in a 60mm f 15 refractor.
by Merlin66
Sat Sep 01, 2018 1:04 am
Forum: Solar Radio, Magnetometry and Spectroscopy
Topic: 08Aug: Spectral sweep through the Ca K line
Replies: 13
Views: 658

Re: 08Aug: Spectral sweep through the Ca K line

Peter, As you appreciate it's always difficult to estimate the resolution from spectra comparison. A spectral reference lamp is the preferred method. Notwithstanding, I think you're pretty close in your estimates.... I ran your spectroheliograph through the SimSpec_SHG for comparison...... SimSpec S...
by Merlin66
Thu Aug 30, 2018 10:56 am
Forum: This is SolarChat !!
Topic: New camera but which one?
Replies: 32
Views: 831

Re: New camera but which one?

The T2 tilter works very well for me with the ASI 174mm.
by Merlin66
Thu Aug 30, 2018 9:52 am
Forum: This is SolarChat !!
Topic: New camera but which one?
Replies: 32
Views: 831

Re: New camera but which one?

After all the discussion, what camera were you using???
by Merlin66
Wed Aug 29, 2018 4:24 am
Forum: Solar Radio, Magnetometry and Spectroscopy
Topic: 08Aug: Spectral sweep through the Ca K line
Replies: 13
Views: 658

Re: 08Aug: Spectral sweep through the Ca K line

Peter,
Well done mate!
What bandwidth were you using??
by Merlin66
Tue Aug 28, 2018 11:00 pm
Forum: This is SolarChat !!
Topic: New camera but which one?
Replies: 32
Views: 831

Re: New camera but which one?

DON'T buy an ASI 183mm for solar narrowband imaging. I went through the same thought analysis - using the ED80 (600mm fl) and the PST mod (>1000mm fl) and the ASI 174 I have... I did buy an ASI 183mm - and had "issues" - these were final recognised and accepted by ZWO who stated "due to technical is...
by Merlin66
Thu Aug 23, 2018 8:25 am
Forum: Solar Scope Modifications
Topic: How to double stack a Lunt CaK Module? And ERF?
Replies: 27
Views: 980

Re: How to double stack a Lunt CaK Module? And ERF?

I thought the Baader CCD-D was a good ERF for the CaK....
I need to put it on the spectrograph to see what if any the transmission is >400nm.
I’ll post the results......
by Merlin66
Sun Aug 12, 2018 8:22 am
Forum: Commercial Solar Filters/Cameras/Hardware
Topic: What camera do you use?
Replies: 13
Views: 628

Re: What camera do you use?

I tried the ASI 183MM with the smaller pixels and had “issues” which Was acknowledged by ZWO an not being suitable for narrowband Ha solar...they offered a refund and I replace it with the ASI 1600MM which seems to be working well for me. The ASI 178 has the same pixel size as the ASI 183MM but I ha...
by Merlin66
Sun Aug 12, 2018 3:39 am
Forum: Solar Radio, Magnetometry and Spectroscopy
Topic: 08Aug Spectroheliograms
Replies: 10
Views: 384

Re: 08Aug Spectroheliograms

Peter,
Excellent results!!!
Well done.
by Merlin66
Sat Aug 11, 2018 10:00 pm
Forum: Commercial Solar Filters/Cameras/Hardware
Topic: What camera do you use?
Replies: 13
Views: 628

Re: What camera do you use?

Hmmm, that's interesting.
I use the ASI 174 and find most times I get NR and need to use the Tilter. The new ASI 1600 so far has not shown any NR.....
I use FireCapture.
by Merlin66
Sat Aug 11, 2018 9:59 pm
Forum: Commercial Solar Filters/Cameras/Hardware
Topic: What is a blocking filter function?
Replies: 3
Views: 267

Re: What is a blocking filter function?

The blocking filter is an extremely narrow band (10A) filter centred on Ha. This is mandatory with an etalon type filter to effectively "sort" the myriads of band passes obtained to just allow the one at Ha to pass through.

I think your application with the telelens may have to be re-assessed.
by Merlin66
Thu Aug 09, 2018 7:55 am
Forum: Commercial Solar Filters/Cameras/Hardware
Topic: What camera do you use?
Replies: 13
Views: 628

Re: What camera do you use?

Stefan,
I use an ASI 174mmfor fl above 1000mm and now testing an ASI 1600mm for shorter fl.