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"NAKED EYE" HORSEHEAD

Started by Thomas Dey, 11/14/2015 10:08PM
Posted 11/14/2015 10:08PM | Edited 11/14/2015 10:18PM Opening Post
I consider the Horsehead to be right up there as one of the most challenging visual targets, and have only seen it a few times under the most ideal conditions. Decent sized scope and a specialized filter like the H-beta especially help - and even then I can only occasionally say, "Yep - OK - I definitely see it!" One of those objects that images superbly in H-alpha but not to the eye in that band because it is so blasted DIM and our Night Vision "scotopic - rods" are blind to the uber-red H-alpha. So far, so challenging. About a month ago I got TWO Gen 3 Night Vision monoculars, added 12nm H-alphas and looked at the sky. YIKES! All the H-alpha stuff just POPS because the device of course transforms the view to bright green phosphor that one can look straight at. I can see Barnard's Loop piece of cake and the nebulosity to the E and S of Orion's left belt star no problem at all. I had assumed the Horsehead Notch (B33) would be impossible at 1x. But tonight I looked again and - I SEE IT! Just as it should appear, a tiny dark notch hooking in from the left and upward. Again and again I ask myself if I'm actually seeing it at 1x and the answer keeps coming back - Yep...there it is. So now, after the fact - I check the literature and see it is about 4 arc-min in size (certainly resolvable by cone's centralis vision) and the NV 1:1 phosphor rates 64 line pairs/mm At a 1-inch focal length (both objective AND eyep), that translates to about 2 arc-min (for the pair) --- which would be just comfortable to resolve the object. I'm also convinced that using the TWO NVs feedng BOTH eyes immensely reduces the scintillation. So there you have it - I can see the Horsehead at unity mag using Gen 3 NV True Binos. And that's pretty amazing! Has anyone else tried this?! If you think I'm nuts, I understand. Comments/observations welcome! Tom

29-inch Dob in a dome
36-inch upgrade soon
LUNT 80/80 solar scope
FLI 6803 cam
APM 100mm APO Binos
JMI RB-16 Night Vision Binos
Zeiss 20x60 IS binos
Posted 11/14/2015 11:08PM #1
Thomas Dey said:

I consider the Horsehead to be right up there as one of the most challenging visual targets, and have only seen it a few times under the most ideal conditions. Decent sized scope and a specialized filter like the H-beta especially help - and even then I can only occasionally say, "Yep - OK - I definitely see it!" One of those objects that images superbly in H-alpha but not to the eye in that band because it is so blasted DIM and our Night Vision "scotopic - rods" are blind to the uber-red H-alpha. So far, so challenging. About a month ago I got TWO Gen 3 Night Vision monoculars, added 12nm H-alphas and looked at the sky. YIKES! All the H-alpha stuff just POPS because the device of course transforms the view to bright green phosphor that one can look straight at. I can see Barnard's Loop piece of cake and the nebulosity to the E and S of Orion's left belt star no problem at all. I had assumed the Horsehead Notch (B33) would be impossible at 1x. But tonight I looked again and - I SEE IT! Just as it should appear, a tiny dark notch hooking in from the left and upward. Again and again I ask myself if I'm actually seeing it at 1x and the answer keeps coming back - Yep...there it is. So now, after the fact - I check the literature and see it is about 4 arc-min in size (certainly resolvable by cone's centralis vision) and the NV 1:1 phosphor rates 64 line pairs/mm At a 1-inch focal length (both objective AND eyep), that translates to about 2 arc-min (for the pair) --- which would be just comfortable to resolve the object. I'm also convinced that using the TWO NVs feedng BOTH eyes immensely reduces the scintillation. So there you have it - I can see the Horsehead at unity mag using Gen 3 NV True Binos. And that's pretty amazing! Has anyone else tried this?! If you think I'm nuts, I understand. Comments/observations welcome! Tom

I admit I have not looked into NV devices at all Thomas....can you post a link to some info on the monoculars you are referring to? Sounds pretty amazing.....

20" MidnighTelescopes f/5
8" f/16 Muffoletto Achro
Meade 6" AR6 f/8.0 Achro
Celestron C11
Parallax PI250 10" F/5 Newt
Vixen FL102S,NA140SS,R200SS
80mm Stellarvue Nighthawk with WO APOupgrade lens, 90mm f/16.67 Parallax Achro
LXD75/LX200, Mini-tower, GP-DX, CG5 ASGT, LXD650, GM-8, G11, GM-100, GM-150EX, GM-200 and a Gemini G40
4" portable AP convertable 44" or 70" pier
Stellarvue M7 Alt-Az, TSL7 Pier/Tripod
12.5" f/5 MidnighTelescopes DOB Swayze optics
Monroe GA