Search found 88 matches

by george9
Thu May 30, 2019 2:59 pm
Forum: Solar Scope Modifications
Topic: Creative Solutions to the Problem of LARGE (8"+) ERF Cells
Replies: 6
Views: 299

Re: Creative Solutions to the Problem of LARGE (8"+) ERF Cells

Is anyone actually interested in purchasing a cell for a 295mm filter today? It would lower the costs to have more than one person. JTW is potentially interested in producing large ones. Thanks for the link, Mark.

George
by george9
Tue May 28, 2019 1:28 pm
Forum: Solar Radio, Magnetometry and Spectroscopy
Topic: Ha sun with SHG
Replies: 9
Views: 175

Re: Ha sun with SHG

Very fun. George
by george9
Sat May 18, 2019 10:32 pm
Forum: Solar Scope Modifications
Topic: C11 ERF-Concept
Replies: 15
Views: 1715

Re: C11 ERF-Concept

Given the thread got bumped recently, I just wanted to point out that diffraction is the smaller problem. The bigger problem is that each filter will have very slightly different thickness and be mounted at a very slightly different angle. A better test than a diffraction mask with holes would be to...
by george9
Thu Apr 25, 2019 1:14 am
Forum: Commercial Solar Filters/Cameras/Hardware
Topic: First solar shot ASI290
Replies: 10
Views: 355

Re: First solar shot ASI290

I stacked about 7 frames and let Autostakkert do its default sharpening. I have a lot to learn about processing and imaging, but I like that it seems to have information almost down to the pixel level, even in the ASI290 at f/7 (92mm). Looking at my best single raw frame, it seems real. Only 7 frame...
by george9
Tue Apr 16, 2019 9:36 pm
Forum: This is SolarChat !!
Topic: NEAF
Replies: 27
Views: 822

Re: NEAF

It was great to see you out at the solar scopes again, Oivind. Always a pleasure.

George
by george9
Mon Apr 15, 2019 1:06 pm
Forum: Commercial Solar Filters/Cameras/Hardware
Topic: First solar shot ASI290
Replies: 10
Views: 355

Re: First solar shot ASI290

Thanks, guys. Those are pretty much my first astronomical images, other than the R2 video and iPhone snaps at the eyepiece. I cannot imagine the difficulty of film. The cameras are still on sale, and if you call High Point, they may still subtract the additional NEAF discount (but I guess this won't...
by george9
Sun Apr 14, 2019 11:40 pm
Forum: Commercial Solar Filters/Cameras/Hardware
Topic: First solar shot ASI290
Replies: 10
Views: 355

First solar shot ASI290

I have to say that I am amazed at the ease of use with an ASI290 I bought on a NEAF sale. My goal is realtime viewing of CaK since I cannot see it. I guess I will end up getting pulled into imaging. But even with just the ASI capture utility, with my PC in the bright sunlight so I could not focus we...
by george9
Sun Apr 14, 2019 11:18 pm
Forum: This is SolarChat !!
Topic: When I win the lottery
Replies: 18
Views: 558

Re: When I win the lottery

Yes, I got an advertising email from Lunt with the prices and posted on CN. Not in the email but 5-inch etalons built on very thick plates so no obstructions, circular polarizer to reduce reflections. I won't be spending $90K, but very fun. Hope to look through it next year at NEAF. Too bad it wasn'...
by george9
Thu Apr 11, 2019 3:48 pm
Forum: This is SolarChat !!
Topic: Double stacking !!!!
Replies: 3
Views: 158

Re: Double stacking !!!!

I stack my Quark with a Lunt DSII unit (intended for an LS80) on my 155mm.

George
by george9
Tue Apr 09, 2019 11:20 pm
Forum: This is SolarChat !!
Topic: new spot and intens prom in several freq
Replies: 15
Views: 372

Re: new spot and intens prom in several freq

Very nice catch on that prom! Amazing. What size scope was the Mg on? At NEAF, I thought the Mg on the small refractor looked more like a good white light view than even a calcium view (e.g., the two active regions were bright enough in CaK but not visible to me in Mg). But your images show more. Da...
by george9
Tue Apr 09, 2019 11:24 am
Forum: This is SolarChat !!
Topic: NEAF
Replies: 27
Views: 822

Re: NEAF

Thanks so much for the nice photo, Franco. I had a steady line all day long Saturday without a single lull. We got lucky on the weather and on the seeing. The tradeoff is that you don't get to play, but I did get around on Sunday before putting up the CaK. Also picked up things like rings for my LS8...
by george9
Sat Apr 06, 2019 12:12 am
Forum: This is SolarChat !!
Topic: NEAF
Replies: 27
Views: 822

Re: NEAF

Yes please come out. I should be there both days. May set up a little later than usual for the ground to dry a bit first, but it should get sunny even Saturday. So not sure if I'll make DayStar at 10am or will be outside.

George
by george9
Thu Apr 04, 2019 9:52 am
Forum: This is SolarChat !!
Topic: NEAF
Replies: 27
Views: 822

Re: NEAF

I’ll be set up in the solar party as usual. If it’s cloudy I’ll just have the 80mm for peeks. If nice, then the 80 and a 155mm double stack. Maybe also 70mm with CaK and a video camera.

George
by george9
Mon Mar 25, 2019 3:23 pm
Forum: This is SolarChat !!
Topic: AR12736, Lunt BF1200ST and a BF question
Replies: 18
Views: 439

Re: AR12736, Lunt BF1200ST and a BF question

Excellent shots! Very similar to my set up with an LS80 DSII unit on my 155mm refractor, then a second focuser. Then a Quark chromosphere. And a D-ERF in front. Raf, I assume the LS50 PT unit has incoming and outgoing collimating lenses? When you ask about the Quark blocking filter, the goal would b...
by george9
Fri Mar 08, 2019 2:42 am
Forum: Commercial Solar Filters/Cameras/Hardware
Topic: Lunt Calcium filter
Replies: 7
Views: 422

Re: Lunt Calcium filter

Oops. Thanks for pointing that out, Bart. I meant for imaging. I cannot see CaK. I just meant that they designed it for visual and they usually double cover everything. So if I use it for imaging, the camera will be fine without the Lunt ERF behind the bigger ERF. Yes, for visual, my own rule is alw...
by george9
Thu Mar 07, 2019 9:32 pm
Forum: Commercial Solar Filters/Cameras/Hardware
Topic: Lunt Calcium filter
Replies: 7
Views: 422

Re: Lunt Calcium filter

I suspect this is in another thread, but have people confirmed that the Lunt ERF doesn't cover a frequency otherwise missed by the main components? Lunt tends to double cover frequencies for eye safety (these are rated for visual), so I would guess it is all covered. I wasn't going to remove the Lun...
by george9
Mon Feb 25, 2019 4:04 am
Forum: This is SolarChat !!
Topic: Weekend of fun in the sun with lots of new equipment
Replies: 16
Views: 566

Re: Weekend of fun in the sun with lots of new equipment

Just curious, can shifting the focus in either direction (i.e., pushing the primary mirror in or out) offset some of the spherical aberration in CaK? It would be a lucky coincidence if so. Or is there any stock item (eg, a Barlow) that has a roughly opposite aberration at this frequency that can be ...
by george9
Sun Feb 24, 2019 3:02 am
Forum: This is SolarChat !!
Topic: CaK, 23022019. Double plus triple.
Replies: 7
Views: 335

Re: CaK, 27022019. Double plus triple.

All look good, Bart. Does the third one have a little more gradation of brightnesses in the active region compared to the other two? The first definitely has the least. The second is similar to the third in that respect, but may be a little more washed out in the rest of the disk (non-AR). So that w...
by george9
Mon Feb 18, 2019 12:32 pm
Forum: This is SolarChat !!
Topic: CaK, 16022019. SolarMonitor plus experiments
Replies: 17
Views: 556

Re: CaK, 16022019. SolarMonitor plus experiments

Got it now. Thanks. Awesome project (I had read the thread and its earlier one, but couldn't find it.) So without the 6mm.

Do you think the improvement in #3,4,5 is due to narrowing around 393nm, or due to better blocking of more distant wavelengths, say UV or IR?

George
by george9
Mon Feb 18, 2019 1:19 am
Forum: This is SolarChat !!
Topic: CaK, 16022019. SolarMonitor plus experiments
Replies: 17
Views: 556

Re: CaK, 16022019. SolarMonitor plus experiments

Bart, is the "Lunt blocking filter" their CaK (e.g., B1200), or part of that, or something else? To me, your #3,4,5 are somewhat similar, and all better than #1,2. Those would be triple stacked, more or less if the Lunt filter is the CaK because isn't the bandpass of the CaK about the same as one PS...
by george9
Thu Feb 14, 2019 2:31 pm
Forum: This is SolarChat !!
Topic: The effect of a circular polarizer in a double stack
Replies: 17
Views: 953

Re: The effect of a circular polarizer in a double stack

I agree it is important what the etalons and blocking filters are doing. In my case, the circularly polarized light seems to get fully through the second etalon and blocking filter because the binoviewer, which polarizes when it splits, lets equal light through the two eyepieces. I checked my notes ...
by george9
Wed Feb 13, 2019 12:00 pm
Forum: This is SolarChat !!
Topic: The effect of a circular polarizer in a double stack
Replies: 17
Views: 953

Re: The effect of a circular polarizer in a double stack

Yes exactly. Thanks both. George
by george9
Tue Feb 12, 2019 4:13 pm
Forum: This is SolarChat !!
Topic: The effect of a circular polarizer in a double stack
Replies: 17
Views: 953

Re: The effect of a circular polarizer in a double stack

Just bumping the thread to see if there are any thoughts why the backwards circ polarizer is recommended when forward works great (see last post). George
by george9
Mon Feb 11, 2019 1:13 am
Forum: This is SolarChat !!
Topic: The effect of a circular polarizer in a double stack
Replies: 17
Views: 953

Re: The effect of a circular polarizer in a double stack

Sorry I missed this thread. The circular polarizer is highly efficient at eliminating reflections at a cost of attenuating the main image. My experiments show that it works facing both ways. I place it forward-facing so that I can still use my binoviewer for visual. That way light comes out circular...
by george9
Sat Feb 09, 2019 6:23 pm
Forum: Commercial Solar Filters/Cameras/Hardware
Topic: Help me decide on solar setup
Replies: 8
Views: 917

Re: Help me decide on solar setup

I am a fan of double stacking. Some say that is more important for visual than for imaging, and others find it very important for imaging. I am visual for H-alpha and neophyte imaging in CaK. You mention the LS80, and I love my LS80 DSII with B1800. I optimized it over time with a circular polarizer...