Search found 678 matches

by Bob Yoesle
Fri Apr 09, 2021 5:45 pm
Forum: Solar Scope Modifications
Topic: Red glass inside Lunt LS50THa
Replies: 7
Views: 163

Re: Red glass inside Lunt LS50THa

This is most likely a RG630 filter which blocks UV, with an IR reflecting dielectric coating.

It probably can be removed and used safely with a Bader DERF. You still likely will have another RG630 filter in the Lunt blocking filter.
by Bob Yoesle
Thu Apr 08, 2021 11:02 pm
Forum: This is SolarChat !!
Topic: Looking for source(s) for CaK Blocking Filter(s)
Replies: 17
Views: 215

Re: Looking for source(s) for CaK Blocking Filter(s)

Hi Tim, The "blob" filter is a "rusted" Induced Transmission filter, and it can't be replaced by anything I know of for CaK use. The secondary filter(s) appears to be the missing filter from the eyepiece side of the diagonal. These can be replaced with the Baader K line. The obje...
by Bob Yoesle
Tue Apr 06, 2021 4:09 am
Forum: This is SolarChat !!
Topic: Looking for source(s) for CaK Blocking Filter(s)
Replies: 17
Views: 215

Re: Looking for source(s) for CaK Blocking Filter(s)

I'm assuming you bought this More than likely the main narrow blocker (same as CaK PST "No1" filter) has been removed and the remaining filters are probably "rusted." Per Mark and Alexandra, we'll need to see the components. I'm guessing you have essentially an objective and tele...
by Bob Yoesle
Wed Mar 31, 2021 4:34 pm
Forum: Solar Scope Modifications
Topic: 80mm F10 Telescope for PST Mod and Baader TZ Quark?
Replies: 7
Views: 196

Re: 80mm F10 Telescope for PST Mod and Baader TZ Quark?

Telecentrics are very simialr collimators, and are designed for specific focal lengths and positioning to render precise telecentricity, not focal ratios. That said, Christian's evaluations show using longer focal length objectives work quite well, shorter not so much: Even if they are optimized for...
by Bob Yoesle
Tue Mar 30, 2021 3:25 am
Forum: This is SolarChat !!
Topic: Images from new Solar Spectrum .3A
Replies: 10
Views: 136

Re: Images for new Solar Spectrum .3A

F) Leasons learned from these simulations on mica-spaced Fabry-Perot etalons : In order to benefit from the full performance of mica-spaced F-P etalons, the following requirements are to be met : a) Use of a true telecentric lens system (such as Baader TZ or Beloptik). So called "telecentric B...
by Bob Yoesle
Tue Mar 30, 2021 12:59 am
Forum: This is SolarChat !!
Topic: Images from new Solar Spectrum .3A
Replies: 10
Views: 136

Re: Images for new Solar Spectrum .3A

Hi David, Your first is a negative image and makes it more difficult to judge. I inverted it, and it appears to be the best of the images you posted - pretty close if not on-band and of good uniformity. 3ssasi183.032921 Neg SM.jpg The other images are less uniform, which may indicate there was a bit...
by Bob Yoesle
Mon Mar 29, 2021 4:00 pm
Forum: This is SolarChat !!
Topic: Double-stack Ca K images 28 March and big thanks to Pedro
Replies: 12
Views: 185

Re: Double-stack Ca K images 28 March and big thanks to Pedro

Very nice results Christian, and you likely got shortened exposures by removing the K line filter.

Would someone please remind me of the "false color" process used in FC? Thanks ;)
by Bob Yoesle
Sat Mar 27, 2021 3:58 pm
Forum: This is SolarChat !!
Topic: Ca K solar disk image, March 25, single and double stack - ASI1600
Replies: 15
Views: 225

Re: Ca K solar disk image, March 25, single and double stack - ASI1600

Pretty cool Christian. Any chance you can get a hold of a Coronado PST and/or Lunt CaK filters to see what they look like? The only thing I've ever seen regarding them (I assume they are very similar) is shown below, and it's not too informative:
Lunt CaK Etalon_wide blocking filter.PNG
Lunt CaK Etalon_wide blocking filter.PNG (42.79 KiB) Viewed 98 times
by Bob Yoesle
Sat Mar 27, 2021 3:49 pm
Forum: This is SolarChat !!
Topic: Lunt 60 Triple Stack
Replies: 23
Views: 282

Re: Lunt 60 Triple Stack

Hi Stu, those are wonderfully uniform FD images! And the scope is awesome looking. I'm curious. With my DS Tucson SM90s I have generally found having the tilt-wheels (and therefore tilt angles) 180 degrees apart seems to work best. What "clock setting" orientation do you have for your Lunt...
by Bob Yoesle
Sat Mar 27, 2021 11:00 am
Forum: This is SolarChat !!
Topic: Ca K solar disk image, March 25, single and double stack - ASI1600
Replies: 15
Views: 225

Re: Ca K solar disk image, March 25, single and double stack - ASI1600

Next step is triple stacking, just like Pedro in Ha ... No, just joking ;-)
I'd give it a shot Christian !-)
by Bob Yoesle
Sat Mar 27, 2021 10:50 am
Forum: This is SolarChat !!
Topic: Newbie advice please
Replies: 19
Views: 169

Re: Newbie advice please

Is it better to get the bigger scope or ds my 50? or is there another alternative?
Get the larger 60, save up for the external 60 mm double stack etalon. You'll be glad you did.
by Bob Yoesle
Fri Mar 26, 2021 6:47 am
Forum: This is SolarChat !!
Topic: Combine disc and prom stacking
Replies: 16
Views: 288

Re: Combine disc and prom stacking

I believe Jordan stated he's using GIMP and wants to use something different:
I have been using GIMP (free) for my photo processing, but am ready to throw in the towel and succumb to Photoshop.
by Bob Yoesle
Thu Mar 25, 2021 9:42 pm
Forum: This is SolarChat !!
Topic: Combine disc and prom stacking
Replies: 16
Views: 288

Re: Combine disc and prom stacking

Consider PaintShop Pro. Everything you need, and you own it.

Review
by Bob Yoesle
Thu Mar 25, 2021 9:26 pm
Forum: This is SolarChat !!
Topic: Ca K solar disk image, March 25, single and double stack - ASI1600
Replies: 15
Views: 225

Re: Ca K solar disk image, March 25, single and double stack - ASI1600

Lovely full disc's Christian.

The DS is clearly superior to the SS...
by Bob Yoesle
Tue Mar 23, 2021 7:40 pm
Forum: This is SolarChat !!
Topic: Combine disc and prom stacking
Replies: 16
Views: 288

Re: Combine disc and prom stacking

I use a double stacked filter system and processing which makes this unnecessary. But even with a single stacked etalon and single exposure with the proper dynamic range it becomes unnecessary . Otherwise you can you use your favorite photo-manipulation software to cut and paste, or otherwise blend,...
by Bob Yoesle
Tue Mar 23, 2021 7:04 pm
Forum: This is SolarChat !!
Topic: Any ideas? mystery bubble
Replies: 30
Views: 585

Re: Any ideas? mystery bubble

Another poster of Andy's video has several links on Cloudy Nights. This earlier one by Berger seems to cover the subject of Andy's video, and the Space.com article quoting Berger, quite well.
by Bob Yoesle
Mon Mar 22, 2021 6:53 pm
Forum: This is SolarChat !!
Topic: Apollo Lasky banned again
Replies: 9
Views: 440

Re: Apollo Lasky banned again

Being kind, truthful and above all safe is an important part of it. I had realised that there was something very-wrong with the continued misuse of this valuable forum and would never (and do not approve) of getting and/or trying-out any such items for Solar-viewing, whatever they may be, unless pr...
by Bob Yoesle
Sat Mar 20, 2021 5:05 pm
Forum: Solar Scope Modifications
Topic: Experimenting with double stacking Daystar filter with ...
Replies: 19
Views: 1210

Re: Experimenting with double stacking Daystar filter with ...

Thanks for the correction and clarification Mark!
by Bob Yoesle
Fri Mar 19, 2021 9:57 pm
Forum: Commercial Solar Filters/Cameras/Hardware
Topic: Solar Spectrum Filter. What is needed to make it work?
Replies: 10
Views: 193

Re: Solar Spectrum Filter. What is needed to make it work?

Hi James, Be sure to read the link to Christian's site. I'd go with the Baader TZ4, which will give you f/32 with the Tak f/8. there generally would be no more "powerful" telecentric. I believe the TZ's were designed around an objective with an 800 mm FL, which is ideal for the FS102. Afte...
by Bob Yoesle
Fri Mar 19, 2021 7:01 pm
Forum: Commercial Solar Filters/Cameras/Hardware
Topic: Solar Spectrum Filter. What is needed to make it work?
Replies: 10
Views: 193

Re: Solar Spectrum Filter. What is needed to make it work?

Hi James, Yes - but avoid a Barlow or Powermate and instead get a real telecentric lens system to give it at least f/30 (Baader or BelOptik), and an ERF above 80-100 mm is highly desirable. FYI, telecentric systems do not produce parallel light to an etalon (that is more applicable to a collimator s...
by Bob Yoesle
Fri Mar 19, 2021 6:06 pm
Forum: Solar Scope Modifications
Topic: Experimenting with double stacking Daystar filter with ...
Replies: 19
Views: 1210

Re: Experimenting with double stacking Daystar filter with ...

Looks good Apollo. You might also want to consider getting a hold of Mark at Solar Spectrum, especially since you're dealing with the T-scanner needing to be operated at an "ambient" temperature. Mark will be able to set it up on his spectroscope and tell exactly what temperature is on-ban...
by Bob Yoesle
Fri Mar 19, 2021 1:17 am
Forum: This is SolarChat !!
Topic: CaK disc comparison between SS and DS
Replies: 55
Views: 1224

Re: CaK disc comparison between SS and DS

When the seeing cooperates I can record filaments in CaK as well as the occasional prom.
Hi Ken,

According to Bob 71741 calculations for a two-filter Lorentzian, you have the following parameters for your double stacked CaK system:

Image1.jpg
Image1.jpg (11.05 KiB) Viewed 160 times
by Bob Yoesle
Thu Mar 18, 2021 8:43 pm
Forum: This is SolarChat !!
Topic: CaK disc comparison between SS and DS
Replies: 55
Views: 1224

Re: CaK disc comparison between SS and DS

Hi George - more like useless... I'd also like to know the answer to Marty's question to Ken, and what Ken is using for his DIY system... If you look at what Peter Zetner did with his SHS to simulate what different CaK FWHM's would look like, and concluded a FWHM of around 0.5 Å or less would be opt...
by Bob Yoesle
Thu Mar 18, 2021 6:34 pm
Forum: Solar Scope Modifications
Topic: Experimenting with double stacking Daystar filter with ...
Replies: 19
Views: 1210

Re: Experimenting with double stacking Daystar filter with ...

Hi Christian, I don't know if the following will help, but until Mark responds I assume that they are linear polarizers: The Dobrowolski patent is silent on the type of polarizer. However, the references I have seen for both the mica and the magneto optical filter used for solar astronomy state they...