The Horsehead has been Vanquished

[rene-gedaly]

Still only in my mind's eye, Stephen. But I do have my own magic horse head eyepiece as of this year.

[edward-fraini]

I have looked for the horse head many time with no luck but was not aware of the size till Walt showed it to me in his 25 inch DOB. (With filter). I was always straining to see something smaller. I can see how proper sizing with the "magic" eyepiece would help. I am curious if this concept would translate to other deep sky objects as well. So I know how to calculate exit pupil. How do I select the proper value

First attempt at tapatalk. Errors due to fat thumbs.


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[steve-fung]

Hi Ed, exit pupil specifications for different filters (and their uses) are specified on Lumicon's website (scroll down to the middle):

http://www.lumicon.com/store/pg/15-LUMICON-Nebula-Filters.aspx

Here are additional websites where folks compared various filters with select DSOs

http://freescruz.com/~4cygni/horsehead/NebulaFilters.htm

http://www.prairieastronomyclub.org/resources/by-dave-knisely/filter-performance-comparisons-for-some-common-nebulae/

Hope that helps.

[mark-ferraz]

Stephen vanquished the horse head on my scope and it was really exciting. I never could have found it on my own...


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[kerry-davis]

Hey guys, I wanted to chime in on viewing the Horse Head! Finding it was one of the most difficult albeit pleasurable objects I've ever encountered. I have a drawing I made of it along with some notes I made that night. Perhaps I can scan the drawing and figure out a way to link it here. Anyway on March 10, 1989 at Columbus at 8:00 PM I logged the observation of it using my 13" Coulter Dobsonian(long gone now), a UHC filter and a Teleview 24MM wide field eyepiece(no longer made) along with a barlow producing 112 power. I used the higher power because contrast was of the essence and had been recommended to find it. Here are my written out notes from that night:

"Incredibly difficult to see at first. I spent almost an hour with a black velveteen cloth over my head before I could see it. Could see only with averted vision. More prominent when I rolled my eye to the left side. Very low contrast. Just slightly more opaque than the sky background. Caught a few excellent glimpses of horse head shape. It was quite eerie during those moments. Once I located it I could relocate it without the cloth over my head and this was with a three day moon 20 degrees in the sky! I've never looked at a fainter object. The drawing was done totally from memory except for the field stars as I couldn't see the nebula with direct vision. I studied it for about 20 to 30 minutes."

Just reading your comments on it and revisiting my own make me want to see it again. It has been too long!

[rene-gedaly]

Dusting off the forums this morning, felt called to comment on this post. I've "seen" the horsehead twice now in Mark's 25" but am not claiming a hit for the Dark Nebula AstroLeague list (against the rules!). I want to see it for myself in a 10 or 11.5" Dob which is all the aperture I have since those are my traveling scopes. May be at ESP this year, just can't bring myself to travel to OkieTex. Wouldn't seem so far away if I took two days to get to TSP but I do it one daydreaming drive. Watch out for the little purple Honda Fit.