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Do you do/like solar observing??


Carl

Do you do/like Solar observing?  

25 members have voted

  1. 1. Do you do/like Solar observing?

    • Yes i like it
    • No i don`t like it
      0
    • I do like it But i can`t be bothered to do it
    • Sometimes i do
    • I`d like to do it BUT i`ve not got the right equipment
    • I`d like to do it.BUT i`m scared in case my solar filter does not work properly


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I view the Sun at just about every chance I get! Saying, "there's only sunspots" is like saying "there's only the Grand Canyon"!! Like every other observed object, the more you look, the more you'll see. Once you know how to observe the Sun, the better it is.

Example 1) White light filters.

There are many types and colors. First, the popular "Mylar" or Baader Film filters. These are thin film filters and generally show the Sun in a bluish-whitish tint. This is actually a more natural color of the Sun. Being classified as a GIIV, the Sun's color is really more like bright clouds than yellow, since the blue light is dispersed by the atmosphere. These filters let in the most light, which makes them great for photography. If you have one of these white filters, you can place a yellow or orange filer in the eyepiece to increase contrast. Try all colored filters you have, too. Each one will bring out different details, allowing you to see more features on the Sun, (of which there are several, and I'll describr them later.)

Thousand Oaks Full aperture Glass type II.

This is one of the white light filters I have. (The pictures of the Sun on my website were mostly taken through this filter) It gives the Sun a yellow/orange color, more what we think the Sun looks like. It's great for wide viewing, since it gives high contrast, but cuts too much light to work well for high power or photography. Even so, I've got some pretty good pictures through mine.

Orion Full Aperture glass filter.

This one is kind of a pinkish yellow filter. It's an odd color, but it lets in more light than the 1K Oaks, so it's brighter. More for smaller apertures, such as for the ETX series and small (6") newts, it holds up to higher powers in those scopaes.. I Haven't tried photos through one, but I'd think they'd turn out well.

Hydrogen Alpha filters.

These can be extremely expensive and finicky to use, but if you get a chance to use one, definitely do so. These allow you to see the hot, faint solar prominences at the edges of the Sun and filaments across the face, among other things. The aforementioned PST, (Coronado's Personal Solar Telescope) is a relaitely cheep ($500US) investment and is nearly idiot proof. It come in all one piece, faactory collimated and includes a no brains needed finder scope. Fair to good images at a down to Earth price.

More expensive HA filters include the Coronado line. They come in sizes from 40mm to 90mm and cost from $1200 to $5000US +. I had one at the Grand Canyon Star Party this year, attached to my $80 Meade 80mm refractor. $3000 filter on a $80 scope. Gave AMAZING views!

Right now is not a particularly good time to start observing the Sun, BTW. The Solar Maximum was observed about 3 years ago, and the Sun is currently on the downward swing in activity. It will bounce up and down in sunspots for the next few years, but mostly down. You have to check regularly than, to see in anything is happening or you'll miss it. Spots will not be as large as in the past few years, and thus will not last as long.

That said, what to look for on the Sun:

In white light, using the FULL APERTURE filters above, (it's the only way to be safe) you'll first notice sunspots-darker regions of cooler plasma across the face. Look carefully at the sunspot itself. You can see that the center of a large spot will appear nearly black, while the area just around it appears mottled. The center area is the Umbra, the mottling is the Penumbra-just like in an eclipse. The umbra is an area of very high magnetic flux, which cools the plasma and makes it appear dark. The penumbra is light, because the magnetic filed lines are not as dense, therefore some of the hotter plasma is visible around or under it. Sometimes, hot plasma flows along the magnetic field lines above the umbra, allowing you to see bright plasma or "light bridges" overe the spot.

Next, look closely at the umbra itself. If the seeing is good, and your filter stands up to high power, you can pick out details in the penumbra. Small filaments of mottled plasma of different temperatures look like fur from a grey fox or tabby cat. The patterns seen in the penumbra closely trace the magnetic lines that create the spot.

Next, look closely just outside the penumbra. This is where the heat goes, being deflected from the sunspot. You can see bright, mottled areas here. These will be the bright "plages", (with a long A as in Father). When plages are near the edge, or limb of the Sun, they show the "orange peel" effect the best. These are the cells or "granularity" that everyone wants to see. They're subtle in white light and very dependant on seeing. Bubbling clumps of plasma, they're on the order of a few hundred miles wide at the largest. It takes practice to see them, and this is one of the times colored filters may help. Plages are what you want to look for when the SAun doesn't show any big sunspots. These will be areas to keep an eye on for future activity. They are given "active region" numbers by the Mount Wilson observatory, many times before a visible sunspot evolves.

While carefully watching sunspots, you can see them change structure on a time frame close to watching clouds develope. They don't appear to move much in real time, but glimpsed over a few minutes, they show remarkable changes!

In Hydrogen alpha, some other features appear. First off, prominences. These are huge plumes of plasma leaping off the edge of the Sun. Since they glow hotter than the surface, the ionized hydrogen atoms must be singled out to see them. Otherwise, they are lost in the white light of the photosphere. Once seen though, I can't help trying to gauge their sizes. Figuring the Sun is 863,000 miles across, and our Earth is only 8,300 miles or so, you could string 109 Earths across the equator of the Sun. Picture this anytime you observe "small" sunspots or prominences. Anyway, prominences will be seen first.

Look next for dark "whisps" of cloud-like features across the face. These are "filaments" and are simply prominences when seen from the top. Sometimes, they last long enough to rotate to the edge and appear as prominences, but not often. They are dark only when compared to the surface.

Around sunspots, you can see large areas of disturbed plasma. These will sometimes brighten into flares. These flares can become coronal mass ejections, (CME) if sufficiently violent, and cause the aurora someone mentioned before.

Looking at the Sun in H-Alpha makes it easy to see Supergranulation. The orange-peel effect noticed earlier, but on a much larger scale. The super cells lie below the white light granularity and heat it by convection. Think of them as big bubbles at the bottom of boiling porridge. Supercells are hundreds to thousands of miles across, some reaching continent-sized clumps.

At the edges of the Sun in HA, crank up the power to see small, grass-like filaments called "spicules". These are the "moss" someone mentioned before, and are the interface between the chromosphere and the corona. They consist of hot plasma following magnetic field lines once again, but on a small scale that allows interesting, not well understood physics to heat the corona higher than the "surface". (A better explanation of this process is in Pasachoff's book, Nearest Star.)

Well, that about covers observing the Sun, although some things I've left out.

I observed the Sun today in fact, with my 5" F/14 solar scope I built myself. I'll upload a picture of it shortly, alonf with a solar picture that turned out reasonably well.

If you want to see some other solar pics I took, you can check my website under "Astrophotos-Solar".

[glow=red,2,300]Yes Astroman thanks alot for that.I was thinking of getting a Baader Solar Continuum Filter (540nm) 50.8mm.And i was just wandering since you know alot,what would i see on the Sun e.g Prominences etc..

-Cheers- [/glow]                                              :sunny: moonhunter  :sunny:

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Astroman,

How do you rate the BAADER solar film for safe viewing please?

James

James and Moonhunter, et al:

The Baader film will show all of the white light stuff I described in the above dissertation-plus some of the stuff I left out, such as "limb darkening". If you've visited my site and seen the whole disk images there, you'll recognize limb darkening as the appearence of the Sun being darker around the edges and brighter in the middle. This is due to our perspective-looking at a gas ball hundreds of thousands of miles in diameter. As you look at the center, you're looking through less gas than along the edges. Same as observing objects at the zenith and near the horizon here, except here you look through maybe 50 miles of gas and you look through thousands of miles on the Sun.

James: It's a wise thing to be careful. After all, it would only take a second to lose your eyesight to a tragic mistake while observing the Sun through a telescope. That's why ALL solar filters are designed to fit over the full, main aperture of the scope you intend to use. It's important to cover the entire observing surface, to cut down light BEFORE it reaches the eyepiece. This keeps everything cool and risk free. Otherwise, solar filter manufacturers would be run out of business very quickly. As long as you apply the technology according to strict safety standards, you'll be fine.

The Baader film is thin, as I said. But it is also amazingly tough. I've used it on everything from 10X50 binoculars, to 5" refractors up to a 10" SCT. All full aperture, (or apertureS, in the case of binocs), with no trouble and no worries. The only thing you must do is inspect it each time before you look through the scope. I do this by simply holding it up to the Sun before mounting on the scope and looking at the entire surface for bright spots that would indicate pin holes. Very small ones are normal and are of no concern, but larger ones can be trouble. It's extremely difficult to tear the film, unless it's already got a small tear in it. That's why you look FIRST. Then, it's just a matter of securing it tightly to the scope so it won't blow off. Velcro works great. Duct tape works too, but is messy since it melts in the Sun. My Baader film for the C8 is stretched on a wood frame I built. It mounts on the scope such that a twist about the main optics fixes it much like the dust cover-friction is your friend!

It's also very good for observing. Do try the colored filter tricks I mentioned. You'll be suprised at how different each view can be! Don't limit yourself to just wratten filters, either. Try your nebula filters, too. UHC, OIII and such work well.

Most importantly, don't be afraid. Fear is bad. Respect is good, but fear is bad. Treat solar observing like you do electricity-with a healthy, cautious respect, and you'll be fine.

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Most importantly, don't be afraid. Fear is bad. Respect is good, but fear is bad. Treat solar observing like you do electricity-with a healthy, cautious respect, and you'll be fine.

Wise words Astroman i will be solar observing by the end of the week employing all safety measures :clouds2:.

Thanks

James :clouds2:

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[glow=red,2,300]Yes Astroman thanks alot for that.I was thinking of getting a Baader Solar Continuum Filter (540nm) 50.8mm.And i was just wandering since you know alot,what would i see on the Sun e.g Prominences etc..

Astroman,

How do you rate the BAADER solar film for safe viewing please?

James

James and Moonhunter, et al:

The Baader film will show all of the white light stuff I described in the above dissertation-plus some of the stuff I left out, such as "limb darkening". If you've visited my site and seen the whole disk images there, you'll recognize limb darkening as the appearence of the Sun being darker around the edges and brighter in the middle. This is due to our perspective-looking at a gas ball hundreds of thousands of miles in diameter. As you look at the center, you're looking through less gas than along the edges. Same as observing objects at the zenith and near the horizon here, except here you look through maybe 50 miles of gas and you look through thousands of miles on the Sun.

James: It's a wise thing to be careful. After all, it would only take a second to lose your eyesight to a tragic mistake while observing the Sun through a telescope. That's why ALL solar filters are designed to fit over the full, main aperture of the scope you intend to use. It's important to cover the entire observing surface, to cut down light BEFORE it reaches the eyepiece. This keeps everything cool and risk free. Otherwise, solar filter manufacturers would be run out of business very quickly. As long as you apply the technology according to strict safety standards, you'll be fine.

The Baader film is thin, as I said. But it is also amazingly tough. I've used it on everything from 10X50 binoculars, to 5" refractors up to a 10" SCT. All full aperture, (or apertureS, in the case of binocs), with no trouble and no worries. The only thing you must do is inspect it each time before you look through the scope. I do this by simply holding it up to the Sun before mounting on the scope and looking at the entire surface for bright spots that would indicate pin holes. Very small ones are normal and are of no concern, but larger ones can be trouble. It's extremely difficult to tear the film, unless it's already got a small tear in it. That's why you look FIRST. Then, it's just a matter of securing it tightly to the scope so it won't blow off. Velcro works great. Duct tape works too, but is messy since it melts in the Sun. My Baader film for the C8 is stretched on a wood frame I built. It mounts on the scope such that a twist about the main optics fixes it much like the dust cover-friction is your friend!

It's also very good for observing. Do try the colored filter tricks I mentioned. You'll be suprised at how different each view can be! Don't limit yourself to just wratten filters, either. Try your nebula filters, too. UHC, OIII and such work well.

Most importantly, don't be afraid. Fear is bad. Respect is good, but fear is bad. Treat solar observing like you do electricity-with a healthy, cautious respect, and you'll be fine.

Hi Astroman

Not to be rude but i`ve already got the white filter you know the one where you see the sun as the same as Skyguys(Wicked)images..

I was just wandering since you know alot,what would i see on the sun when i use the Baader Solar Continuum Filter. e.g Prominences etc..

-Cheers-

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No Moonhunter, you won't see prominences with a white light filter. Baader film, Thousand Oaks glass and Orion filters are all white light filters. You need a hydrogen alpha filter to see prominences, filaments, faculae, spiculae,super cells and all that other stuff I described in the HA section. You can see sunspots, the umbra and penumbra, limb darkening, plages, light bridges, granulation and maybe a white light flare near a sunspot group with the Baader film. This is a good filter to use your colored filters with, too. I like the darker ones, like #25 red or the green one....38 or something, I forget the wratten number off the top of my head. My UHC filter is green, too and gives excellent contract with the Baader film.

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  • 9 months later...
  • 4 weeks later...

Nice stuff there Tony.

I have a pair of practica 14x25 bins I got from a bargain store for £3. Have them fitted with Baader film for Solar check ups. Saw a large spot up there this afternoon - wished I'd got filters for the scopes - hmph - I gotta get a new sheet of film to make new filters for my fractors. Haven't done Solar thru the Tal100r yet and can't wait. Will have my camera phone at the ready too, heh :D

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  • 5 months later...

Hi all. I m new here and I have a question, hope you can tell me. I m going to buy a sheet of Baader solar film and will make a filter from it for my 10x50 bins. From the things that I read, I think I will cut 2 rings of cardboard with the inner diameter the same as my bins' objective dia. Then I will sandwich the Baader film between the 2 rings, using glue. The filters then will be attached to my bins' objectives using something like velcro.

I just wonder about this thing. For protection of the film and for easy handling, should I sandwich the Baader film between 2 sheets of transparent plastic before making the filter? Will the view of the sun, passing through the sheets of plastic, be modified?

Thank you guys.

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I would suggest that you put nothing but the Baader film in front of the Bins. Make doubly sure that it can't fall off, ever. Look at the sky close to the sun to test for holes, any bright bits and you need to chuck the filters away and start again.

There's no rush to do this as the sun is totally devoid of spots now and probably will be for months. We are in the solar minimum when the spot count is at it's lowest so there's basically nothing to see but a white disc.

Captain Chaos

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