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Transit of Mercury in the Spicule Layer. Phil took this great image with his Quantum 6 Scope, Solar Spectrum etalon and PGR Camera.

Welcome to Solar Chat! The best forum for Solar Astronomy
Moving forward from solar cycle 24 to 25

Search found 130 matches

by mdwmark
Wed Sep 11, 2019 7:58 am
Forum: Commercial Solar Filters/Cameras/Hardware
Topic: Blocking filters and wintertime
Replies: 17
Views: 469

Re: Blocking filters and wintertime

The temperature of the blocker is important. You need to match it up with the etalon so that it will block the next peaks. Air spaced etalons use an blocker that is 6-8Ang at the HW. If they are at 6563Ang at 23C for the CW. Then when it is 43C the CW has moved to 6566.3Ang into the red. So Now you ...
by mdwmark
Fri Aug 09, 2019 4:39 am
Forum: Commercial Solar Filters/Cameras/Hardware
Topic: it seems that my Quark is not reaching the working temperature
Replies: 13
Views: 634

Re: it seems that my Quark is not reaching the working temperature

You have a few thing going on that you need to look at. 1) at F/21 the center wavelength has shifted blue( same as tilting the filter). The HW is also broaden out to about 1.3Ang if you started at .7Ang. 2) your using a yellow ERF, so you will be getting a lot more heat into the scope then if you us...
by mdwmark
Sun Feb 10, 2019 2:21 am
Forum: This is SolarChat !!
Topic: Old Coronado BF30
Replies: 27
Views: 2162

Re: Old Coronado BF30

Or not, If that is just a blocker. Then it will turn back on at 750nm in the red. KG3 is down at about 1000nm. So that area between 750 and 1000nm will be leaking energy. That will be enough to be a problem(not to good for your eye). The short side, RG630 will block anything there. If it is really a...
by mdwmark
Sat Dec 01, 2018 1:20 am
Forum: Commercial Solar Filters/Cameras/Hardware
Topic: DayStar T scanner TS-1??
Replies: 18
Views: 2369

Re: DayStar T scanner TS-1??

Gordon Garcia, That's a name from the past. I haven't talk to him in years. I hope he is still around. He did some great stuff with film. SO-410, I wonder how many remember that film. Kodak changed the name later, but I don't remember what it was. Using the tilt for fine adjustment is what I had in ...
by mdwmark
Fri Nov 30, 2018 4:28 am
Forum: Commercial Solar Filters/Cameras/Hardware
Topic: anyone tried one of these yet - Quark Mg
Replies: 8
Views: 1202

Re: anyone tried one of these yet - Quark Mg

I was not happy with the one they brought to the Big Bear convention. It had a strong secondary reflection. (double solar image). But they seem to be happy with it.
Mark
by mdwmark
Fri Nov 30, 2018 4:14 am
Forum: Commercial Solar Filters/Cameras/Hardware
Topic: DayStar T scanner TS-1??
Replies: 18
Views: 2369

Re: DayStar T scanner TS-1??

Ha Ha ha, That's the old TS-2 housing. I came up with that for the etalons that run around 30-40C(the ATM worked poorly there). Del quit using them when I left. They where larger so that a standard rubber strip heater would fit inside. They must have been with the stuff when the new Daystar took ove...
by mdwmark
Mon Nov 26, 2018 11:27 pm
Forum: Commercial Solar Filters/Cameras/Hardware
Topic: That orange PST Rust / A Fungus?
Replies: 4
Views: 676

Re: That orange PST Rust / A Fungus?

that looks like normal failure
Mark W.
by mdwmark
Mon Nov 19, 2018 1:21 am
Forum: Commercial Solar Filters/Cameras/Hardware
Topic: Rust on either Lunt or Coronado
Replies: 7
Views: 1194

Re: Rust on either Lunt or Coronado

That's not a humidity problem on the images. Humidity usually fails from the outside in. This is something different.
Mark W.
by mdwmark
Fri Nov 16, 2018 8:15 am
Forum: Commercial Solar Filters/Cameras/Hardware
Topic: DayStar T scanner TS-1??
Replies: 18
Views: 2369

Re: DayStar T scanner TS-1??

HI Ken, The normal screw was a plastic knurled-head thumb screw.We would smooth the bottom of the screw so it would not dig into the cell of the filter stack. The easiest way to check the filter. Is to put on the scope, point it at the sun, and without an eyepiece look into the back(red side). Be ba...
by mdwmark
Thu Nov 15, 2018 11:38 pm
Forum: Commercial Solar Filters/Cameras/Hardware
Topic: DayStar T scanner TS-1??
Replies: 18
Views: 2369

Re: DayStar T scanner TS-1??

Hi Ken,
The screw is a 10/32 thread. If you have to change the threads to metric, Take off the back plate with the spring. You should have enough room to run a tap with the cell tilted.
Mark W.
by mdwmark
Wed Nov 14, 2018 8:28 am
Forum: Commercial Solar Filters/Cameras/Hardware
Topic: DayStar T scanner TS-1??
Replies: 18
Views: 2369

Re: DayStar T scanner TS-1??

HI group, The cost of converting the TS-1 to TEC is not that much. But I like to check them out first to make sure the etalon is still good. If you are in Europe they will be ship through Baader Planetarium. So you can contact them about shipping. In the US they would go through Alpine Astro. The bl...
by mdwmark
Thu Nov 08, 2018 7:57 am
Forum: Commercial Solar Filters/Cameras/Hardware
Topic: DayStar T scanner TS-1??
Replies: 18
Views: 2369

Re: DayStar T scanner TS-1??

Well I know of a few that are used. I converted them to a TEC controlled ovens so they will work all year long.
Mark
by mdwmark
Wed Oct 10, 2018 5:53 am
Forum: Solar Scope Modifications
Topic: Pst Cak filter secret -
Replies: 10
Views: 1761

Re: Pst Cak filter secret -

Hi Apollo, Just checking , the GG395 and the KG3 are these hard coated of soft coated? If they are soft coated, then they will need to be used in the back of the telescope. Soft coating filters with that many layers would never come out 1/4 wave on transmission. On the KG3 , the SiO2 overcoat , is t...
by mdwmark
Sat Oct 06, 2018 5:06 am
Forum: Solar Scope Modifications
Topic: Pst Cak filter secret -
Replies: 10
Views: 1761

Re: Pst Cak filter secret - Vengeance against chroma

There prices are right in line with everyone else. That $825 for a two cavity(I would think 2 cavity would do better then OD2) at 1 piece is a good deal. Your idea about how easy it is to make a filter may be true for an AR's or edge filter or something like a 10-20nm HW bandpass. But a ultra narrow...
by mdwmark
Sun Sep 30, 2018 6:03 am
Forum: Solar Scope Modifications
Topic: Narrowest 393.37 ever by Apollo Lasky
Replies: 117
Views: 15204

Re: Narrowest 393.37 ever by Apollo Lasky

Hi Group, OK Christian, I modeled an filter similar to the Chroma. My design came out 1.2Ang which I though was close enough. CW Ang HW Ang %of original transmission at zero deg 3934 1.2 100 At F/30 3933.79 1.23 96 at F/20 3933.54 1.28 86 at F/15 3933.30 1.7 70 at F/10 3932,3 3.2 40 at F/8 3931.7 4....
by mdwmark
Wed Sep 05, 2018 8:30 am
Forum: Solar Scope Modifications
Topic: Narrowest 393.37 ever by Apollo Lasky
Replies: 117
Views: 15204

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

Hi Bob, the only reason I can think of why the .1nm filters has a lower contrast then the PST is that it is not fully blocked. Or it is not on band. There may be a leak in the long side blocking. It is not uncommon to have a blue/green leak that would drop the contrast of the image. Are you using a ...
by mdwmark
Tue Sep 04, 2018 6:07 am
Forum: Solar Scope Modifications
Topic: Narrowest 393.37 ever by Apollo Lasky
Replies: 117
Views: 15204

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

My attempts with the nd 3.8 astrosolar film was for visial. I was not trying to image with it. The filter I was using had 75%T and it was to dark for my eyes.
Mark W.
by mdwmark
Tue Sep 04, 2018 2:14 am
Forum: Solar Scope Modifications
Topic: Narrowest 393.37 ever by Apollo Lasky
Replies: 117
Views: 15204

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

Hi group, The point I was trying to show ,was the Hw of a filter can change depending how it is used and how it is designed. The perfect word calculations is the light is parallel to the filter. The transmission is just for references to show how it decreases with F#. There are at least 5 company's ...
by mdwmark
Fri Aug 31, 2018 4:28 am
Forum: Solar Scope Modifications
Topic: Narrowest 393.37 ever by Apollo Lasky
Replies: 117
Views: 15204

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

What is all this about .1nm or .14nm at K-line. They will both give a great image. With the amount of T ,you will probably need some color glass or an ND filter to drop the transmission down or the exposure will be to fast for the camera. I ask Bob to check if the spacers where high or low index. So...
by mdwmark
Thu Aug 30, 2018 7:31 pm
Forum: Solar Scope Modifications
Topic: Narrowest 393.37 ever by Apollo Lasky
Replies: 117
Views: 15204

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

Bob, You should ask about the design. It is a single cavity filter. The space layer is important to how narrow the filter will be at different F#. If they designed it with a High index space ,that would be the best. With a low index you can get narrower easier but will broaden out faster in F# lower...
by mdwmark
Sat Aug 25, 2018 1:03 am
Forum: Solar Scope Modifications
Topic: Narrowest 393.37 ever by Apollo Lasky
Replies: 117
Views: 15204

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

That's a good company. They make high end hard coated filters. I see that they started to make amateur telescope filters(OPT has some). This must be a out of spec run from a job. The filter is spec at 393.37nm but is better at 393.44nm which is better for K-line. The way the transmission data looks ...
by mdwmark
Fri Aug 17, 2018 4:29 am
Forum: Solar Scope Modifications
Topic: Re: The Double pass idea...
Replies: 13
Views: 2722

Re: The Double pass idea...

double pass has been used with Lasers for a long time, if your working with a point source you fine. A star is a good point source. The sun is not, it has field angle. Lunt tried it with his 8" reflector and it didn't work. If it would have worked it would have been in uses years ago. That .25 deg w...
by mdwmark
Sun Jul 15, 2018 5:57 am
Forum: Commercial Solar Filters/Cameras/Hardware
Topic: NEW direction in the solar narrowband imaging.
Replies: 35
Views: 5119

Re: NEW direction in the solar narrowband imaging.

The graph is for a simple 1/4 wave design. The high end etalons for solar will use a broad band mirror. So they are usually from K-line to Ha or Ha to the Ca lines in the IR.
The broad band mirrors will have more layers which means a higher cost.
Mark W.
by mdwmark
Sat Jul 14, 2018 1:08 am
Forum: Commercial Solar Filters/Cameras/Hardware
Topic: NEW direction in the solar narrowband imaging.
Replies: 35
Views: 5119

Re: NEW direction in the solar narrowband imaging.

That is what I though it would look like. I guested 24Ang peak separation.
Attached is a coating design for Ha. The narrower peaks will be where the transmission is the highest. As the transmission drops the HW will broaden and the bottom of the curve will not be near zero.
etalon mirror Ha.gif
etalon mirror Ha.gif (9.62 KiB) Viewed 1176 times