Observing the Sun

[mathewb]

Hi all,

I have an 8" Newt that I'd like to observe the sun with. I've looked at a couple of the PST scopes and they are really nice, But I cant justify the expense and hassle of dragging two scopes around. I was wondering if anyone has any info at all on a H-alpha filter that I could use to safely view the sun? I'm not really interested in using the white solar film as I cant see the corona or CME's with that, just sunspots.

I have looked, but cant seem to find anything that suits my needs (and is safe... ).

I did mention safe right? I like my eyes.

Cheers,
Matt.

[Merlin66]

If you want to observe in Ha, you really only have two options.
A dedicated Ha scope like the PST or Lunt's or the new Quark Ha eyepiece.
That's about it........

[mathewb]

Thanks,

I haven't heard about the Quark Ha Eyepiece but it sounds exactly what I was looking for.

Many thanks,
Matt.

[Merlin66]

http://www.daystarfilters.com/Quark.shtml

A few teething problems, but is gaining a wide reputation.

[mathewb]

Yes... But at US$995 each (and you need 2 for chromosphere and prominence viewing if I read the blurb correctly) I might just get into spectroscopy instead.....

Cheers,
Matt.

[Merlin66]

99% of the guys who have bought one have gone for the Chromosphere version and use it for both.
Limited FOV - difficult to get full solar disk images (works at around f25/f28 with a short focus f5 scope).

[Merlin66]

Hmmm
Spectroscopy - great idea!
http://www.jtwastronomy.com/products/spectroscopymain.html

I only have three passions in life - my wife, my spectroscopy and my solar.

[h0ughy]

in that order;)?

the drawback on the eyepiece is you also need power. for the money the pst is worth it, as too a SM40 if you can find one

[mathewb]

Hmm ... I'm thinking that I might have to hit up my uni supervisor and see if he has any spectroscopy bits and pieces laying around... I'm guessing that even older stuff would still be suitable for my 8" newt. It's actually something I want to do for my solo project for next years part of my masters.

Otherwise I'm open to suggestions on a good place to get started - make your own or a commercial spectrometer?

*sigh* I just like looking at the sun, even if she is a little bit boring when compared to some of the other stars out there.

Cheers,
Matt.

[Merlin66]

Matt,
You can combine the spectroscopy and solar by building a Spectrohelioscope. Extreme narrow band imaging at ANY wavelength...
The way of the future.
http://www.astrosurf.com/rondi/obs/shg/index.htm
http://www.astrosnap.com/softprotest/Tutorial%20SpectroHelio_Uk.pdf

[OICURMT]

You might want to review the following thread...

http://www.iceinspace.com.au/forum/showthread.php?t=122571

There are no shortcuts in Solar observing, the cost of entry is high.


As for spectroscopy... entry is equally high if you get into the serious end of the hobby.
OIC!

[OzEclipse]

Hi Matthew

I don't think you can fit a hydrogen alpha filter to a reflector - neither newt nor cass. I think it has to be a refractor. It's something to do with the way the interference filter works, I can't remember the exact reason.

The double stack 40mm PST gives remarkable views for it's size. I love mine. Being so small, I put a Polarie on a solid camera tripod and the PST on the polarie it takes me 30s to set up and I can start observing. I went for the double stack option - gives much better views.

cheers

Joe

[Merlin66]

Joe,
An H alpha etalon filter can be fitted to reflectors.
It's just a matter of ensuring you have an effective ERF (energy reduction filter) up front to protect the optics.
You could mount the double stack etalon from the PST in a suitable cell at the front of the reflector and use a blocking filter (BF10/15 etc.) to safely observe and image the solar disk.

[Visionoz]

Ken

At the risk of sounding "stupid" is there a best time to view Sol (obviously other than when it is shining!;)) during daylight hours eg: before noon? before 3pm etc?

Been terrible WX these days in WA and only seems to be good clear nites when either I'm busy working or full moon!!!:mad2: - so interested to look at solar work for a while otherwise I might have to get rid of quite a collection of my gear which has not been used for almost 18 months! I managed to borrow a Coronado SolarMax 90 filter kit recently.

Cheers
Bill

[Merlin66]

Bill, not a silly question...

Best conditions are generally before noon. Steer away from large concrete "heat sinks".
Best of luck!

[Visionoz]

Thanks mate!

That means only on weekends as I need to work to pay for this hobby!

Unfortunately on my EON ED80 I get to see the whole disc rather dimunitively in the 25mm EP and just a simple red disc ... never mind I'll get to grips with it in due time then I would purchase a proper solar scope like the Lunt or SolarMax II - ... but must sell the other stuff to finance it:-(

Cheers
Bill

[N1]

SM 90 - well done Bill. :thumbsup: What story did you come up with :P

Is there a reason you are only using a 25mm EP? Also I would think the SM90 on an ED80 will show pretty good views, even at 24x, which is underutilising it and might be a bit bright for good detail. With that setup you should be able to go way beyond 100x if conditions permit. Any eyepiece will work to some degree. None should be total crap. If you see a featureless red disk, there are 4 explanations I can think of, assuming filter set is installed correctly:

1. Likely: Image too bright at low power, see above. Stop down or increase magnification.
2. Likely: Filter is tuned out. Tune by turning the little brass thumb wheel
3. Possible: You may be looking at a ghost image. My SM60 shows ghost images many degrees from the main image (which means they are not a problem because they are not in the same AFOV as the main image). The first thing I saw through mine when I first got it was such a ghost, and I thought ...k me, the filter's a dud :lol:
4. Unlilkely: Etalon is broken. Better think of a an even better story before returning the equipment :scared3: