I've been visually observing the Sun for a few years, both in white light and Ha. Using a Thousand Oaks glass filter on my Televue NP-101, I've enjoyed observing sunspots nearly every day. I recently purchased a 2" Lunt Herschel wedge with a 1.25" linear polarizer. A local astronomy club was having a star party at a remote site at 5300' elevation. A friend planned to observe the Sun through his TV-102 APO with a Baader film filter. I joined him there, and brought my glass filter and the Wedge. Testing began at mid-morning with acceptable seeing.
First, I observed through the Baader film. The view seemed acceptable, with a solid sunspot grouping and several small sunspots & pores dancing on the edge of visibility. I next observed at the same magnification with the glass filter. While the large grouping seemed the same, the smaller features were marginally more distinct.
Next was the Lunt wedge. First, I tried observing without the polarizer, but the image was much too bright for comfort. In went the filter, and the view was impressive. The penumbral area around the grouping was very distinct, with thin black lines threading out from the umbra. The smaller sunspots now displayed much more detail, and for the first time in the test I was aware of a long archipelago of pores streaming away from the area of the smaller spots. I attempted to see the line of pores through the Baader film but was unable to do so.
To summarize our test:
1. Detail of the photosphere was noticeably improved with the Herschel Wedge.
2. Despite a series of continuous operations for 30 minutes or so, with a 5 minute cooling interval, the red radiating disk never became intolerably hot. Throughout the test I was able to place the back of my hand on the disk for 15 seconds or more without feeling uncomfortable.
3. All who observed the Sun through the wedge were impressed with the level of detail, I'm pleased with the wedge and would recommend it to anyone interested in white light solar observing.
Field testing the Lunt Herschel wedge
- marktownley
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Re: Field testing the Lunt Herschel wedge
A very good evaluation of the wedge! I agree completely!
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- swisswalter
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Re: Field testing the Lunt Herschel wedge
Hi Forrest
I second what Mark wrote, but have you ever seen through a pentaprisma ?
I second what Mark wrote, but have you ever seen through a pentaprisma ?
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- grimble_cornet
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Re: Field testing the Lunt Herschel wedge
I'll third that having done extensive comparisons between solarfilm and the Baader Wedge on 60, 80 and 120mm refractors. However, for me,it was the addition of a Baader Continuum which really gave the wedge a 'punch'.
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Mike Garbett
Selection of Solar and Deep Sky images on Flickr: https://www.flickr.com/photos/mikegarbett/
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Mike Garbett
Selection of Solar and Deep Sky images on Flickr: https://www.flickr.com/photos/mikegarbett/
Re: Field testing the Lunt Herschel wedge
No experience with a penta design. How does it compare, image wise, to the Lunt design?
I've only used the Lunt linear polarizing filter so far. Does the Baader Continuum filter provide a significant improvement over the Lunt filter?
I'll be using the wedge on our observatory TV-102 at a public solar event this Saturday. (IF I can pry our Docent staff away from the scope)
Also, thanks to Mark, we'll be experiencing 'First Light' of our new 100mm Luntanado double-stack. We've had serious smoke pollution from the grass fires here for the last week, which has kept the scopes indoors. Pray for clear sky here this Saturday. :-)
I've only used the Lunt linear polarizing filter so far. Does the Baader Continuum filter provide a significant improvement over the Lunt filter?
I'll be using the wedge on our observatory TV-102 at a public solar event this Saturday. (IF I can pry our Docent staff away from the scope)
Also, thanks to Mark, we'll be experiencing 'First Light' of our new 100mm Luntanado double-stack. We've had serious smoke pollution from the grass fires here for the last week, which has kept the scopes indoors. Pray for clear sky here this Saturday. :-)
- grimble_cornet
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Re: Field testing the Lunt Herschel wedge
I've never used the Lunt linear polarizing filter. I have a variable polarizing filter (2 rotating filters in one mount) which I use for lunar observing. I have tried this with the Baader wedge but it just seems to control brightness whereas the continuum filter improves contrast and makes granulation really pop out.
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Mike Garbett
Selection of Solar and Deep Sky images on Flickr: https://www.flickr.com/photos/mikegarbett/
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Mike Garbett
Selection of Solar and Deep Sky images on Flickr: https://www.flickr.com/photos/mikegarbett/
Re: Field testing the Lunt Herschel wedge
Thanks for the tip. I'll scout around with nearby clubs to check on a continuum filter I can try out.
Worst case, I'll be at the solar conference in Tucson, AZ this fall. I wager I'll discover one there.
Worst case, I'll be at the solar conference in Tucson, AZ this fall. I wager I'll discover one there.