#1  
Old 03-11-2011, 10:36 AM
Geoff45's Avatar
Geoff45 (Geoff)
PI rules

Geoff45 is offline
 
Join Date: Jul 2006
Location: Sydney
Posts: 2,407
Solar photography

If I use a white light full aperture filter and then put in an Ha filter in front of the camera, will prominences show up? I realise with the Ha and white light filter, things will be extremely faint, but will anything show up with a long enough exposure?
Geoff
Reply With Quote
  #2  
Old 03-11-2011, 02:38 PM
frolinmod's Avatar
frolinmod
Registered User

frolinmod is offline
 
Join Date: Dec 2010
Posts: 573
You'd need a sub-angstrom Ha filter. Your typical CCD imaging narrow band Ha filter is 30 to 50 angstroms (3nm to 5nm) wide. That is far too wide to see prominences.

For white light solar viewing I'm currently using a Lunt Herschel wedge with a Baader solar continuum filter and a Lunt zoom eyepiece. The Baader solar continuum filter is a 10nm wide filter centered around 540nm in the green. I can put the Herschel wedge on the back of any refractor, preferably an an APO or semi-APO. I currently have it on a Stellarvue 80ED with a moonlite focuser. Note sure what it would look like to replace the solar continuum filter with an Ha filter. Probably not much. I don't have a 1.25-inch or 2-inch mounted Ha filter to try. But I suspect it would just act like a very deep red filter.

Last edited by frolinmod; 04-11-2011 at 09:03 AM.
Reply With Quote
  #3  
Old 03-11-2011, 03:25 PM
Poita (Peter)
Registered User

Poita is offline
 
Join Date: Jun 2011
Location: NSW Country
Posts: 3,585
Pretty sure the white light filter will block all of the Ha anyway.
Reply With Quote
  #4  
Old 03-11-2011, 03:56 PM
Geoff45's Avatar
Geoff45 (Geoff)
PI rules

Geoff45 is offline
 
Join Date: Jul 2006
Location: Sydney
Posts: 2,407
Seems reasonable. I didn't really believe it could be that simple.
Geoff

Quote:
Originally Posted by frolinmod View Post
You'd need a sub-angstrom Ha filter. Your typical CCD imaging narrow band Ha filter is 30 to 50 angstroms (3nm to 5nm) wide. That is far too wide to see prominences.
Reply With Quote
  #5  
Old 03-11-2011, 09:19 PM
Poita (Peter)
Registered User

Poita is offline
 
Join Date: Jun 2011
Location: NSW Country
Posts: 3,585
Quote:
Originally Posted by ghsmith45 View Post
Seems reasonable. I didn't really believe it could be that simple.
Geoff
That's because it isn't
You will also need an ERF or you will cook the scope, and the sub angstrom filter + ERF could cost more than your scope

I can lend you an ERF, maybe you could buy the 0.5 angstrom filter and we could share
Reply With Quote
  #6  
Old 06-11-2011, 10:39 AM
frolinmod's Avatar
frolinmod
Registered User

frolinmod is offline
 
Join Date: Dec 2010
Posts: 573
Here's a link to what appears to be a picture taken with just such a setup as Geoff inquired about:

http://www.cloudynights.com/ubbthrea...11%20small.jpg

Doesn't look any different than a white light picture really.
Reply With Quote
  #7  
Old 08-11-2011, 12:01 PM
5ash's Avatar
5ash
Earthling

5ash is offline
 
Join Date: Mar 2005
Location: Hunter valley. nsw
Posts: 999
Just remembered an article in scientific american in the 60's or 70's showing how to construct a spectroscope to observe prominances. Maybe that would be an alternative if your handy , though older technology.
Philip

http://www.google.com.au/url?sa=t&rc...i9PYdD9oicOnRA
Reply With Quote
  #8  
Old 08-11-2011, 03:46 PM
frolinmod's Avatar
frolinmod
Registered User

frolinmod is offline
 
Join Date: Dec 2010
Posts: 573
Many years ago while at RTMC I had the pleasure to look through a homemade spectrohelioscope. It could be tuned to any line in the solar spectrum you wanted to observe. Now that was interesting!
Reply With Quote
Reply

Bookmarks

Thread Tools
Rate This Thread
Rate This Thread:

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump


All times are GMT +10. The time is now 11:40 AM.

Powered by vBulletin Version 3.8.7 | Copyright ©2000 - 2019, Jelsoft Enterprises Ltd.
Advertisement
Bintel
Advertisement
OzScopes Authorised Dealer
Advertisement
Lunatico Astronomical
Advertisement
Meade Australia
Advertisement
NexDome Observatories
Advertisement
Celestron Australia
Advertisement
SkyWatcher Australia
Advertisement
Astronomy and Electronics Centre
Advertisement