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zee
super member
Reged: 07/04/07
Posts: 134
Loc: Arizona (varies)
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I've been using my scope for two years now, and I observed more than half the nights of the year before that with naked eye and binoculars, and I have been practicing averted vision all along. I've sketched, I've waited...and my averted vision is just not that useful. I hear these stories from you all about miraculous improvements in what you see using averted vision. I've tried both sides of both eyes, each eye by itself, both together, you name it. But I'm just not getting the boost I hear of from others.
So, what's wrong? Do I need more years of trying? Am I doing something "wrong"? Is it possible that the variation among individual humans means some of us won't get such a boost out of averted vision?
As background, I do wear glasses and have astigmatism. In the past, I never considered myself as having great night vision--in fact, for years I suffered from this condition where at night I saw "snow" over everything, a distracting granularity that made a nighttime trip to the john an adventure. But the snow is gone now, and since embracing astronomy as a hobby I have been pleased with my night vision and adaptation (which does take me a full hour to achieve fully, that much became quickly obvious to me). But the averted vision--no. Just...no.
Any additional advice?
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8" Orion classic dob
15x70 Celestron Skymaster
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tigerroach
sage
Reged: 08/13/08
Posts: 315
Loc: Houston, TX
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Hmmm...
Maybe you are trying to avert your vision too much? What works for me is to look just a little bit to the side of the object - somewhere between the object and the edge of the field.
Also, what kinds of objects are you trying it on? It is mainly for dim DSOs.
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Brian
TeleVue TV-102, Gibralter alt-az mount
Webster 14.5" f/4.3 truss dob *under construction*
Canon 10x30 IS binocs
Edited by tigerroach (09/30/08 08:30 AM)
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Bill Weir
scholastic sledgehammer
Reged: 06/01/04
Posts: 893
Loc: Metchosin (Victoria), Canada
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I think you are just expecting too much. Think subtle. Don't expect it to be like someone has turned on a switch that suddenly illuminates the object.
For myself, averted vision has the most benefit in making an extremely faint object into a very faint object or at best all the way up to faint. Or, it can bring out subtle detail in an already bright object.
Be somewhat sceptical when reading of dramatic increase in brightness claims. Judging brightness can be highly subjective. I'm not talking magnitude, I'm suggesting that what one person will call bright another might call faint.
What kind of objects are you trying this out on? I suggest looking for objects that are close to the limit of what your scope can pick up and using averted vision. It's then that you might notice that seeing nothing, turns into just catching a glimmer of the object. This is where averted vision has its greatest benefits.
Just keep practicing. It will come. Eventually you will find your sweet spot.
Bill
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6'' Orion SkyQuest
12.5'' f/5 Custom Truss Dob
William Optics 80mm ZenithStar II ED Doublet
f/5 25" newtonian on a giant GEM, any time I want
Observing sessions grand total for 2007, 171.
So far in 2008, 115
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Rick Woods
Post Laureate
Reged: 01/27/05
Posts: 4311
Loc: Inner Solar System
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Yeah. An object that's invisible with direct vision, may become barely visible with averted vision. It's that kind of difference. Sometimes it's called averted imagination. Coupled with slightly wiggling the scope, sometimes very faint objects will pop into view. (Or maybe you'll just think they do!)
But it's not a magic bullet, just another trick to try and squeeze a little more out of the view.
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- Rick
14" LX200GPS
8" Meade 826C
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Lard Greystoke
sage
Reged: 07/27/08
Posts: 201
Loc: Ohio
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Since you have an 8", globular clusters might be a good test. Look at the cluster directly, then about 10-20 degrees to the right. For clusters just at your limit, stars should barely pop into view using averted. Which clusters will show this effect depend on darkness of skies - for my 10", NGC 6723 shows this effect pretty nicely.
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Lard Greystoke
10" Odyssey Compact
"With Tantor, the elephant, he made friends. How? Ask me not."
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walt r
Carpal Tunnel
Reged: 02/13/07
Posts: 2421
Loc: Doylestown, PA
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I'd suggest looking at the Blinking Nebula, NGC6826. With direct vision the center star is obvious and the nebula dims and shrinks. With averted vision the nebula flashes larger.
I think this is a good test of whether averted vision is working.
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Walt
Obsession 18" f/4.45 #1370 AN/SC
MK67 Deluxe 6" f/12 Mak-Cass, Super Polaris GEM, JMI MicroMax DSC
DIY 60mm f/6 Achromat
Cookbook 245 CCD
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Tony Flanders
Carpal Tunnel
Reged: 05/18/06
Posts: 2102
Loc: Cambridge, MA, USA
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Quote:
Is it possible that the variation among individual humans means some of us won't get such a boost out of averted vision?
I'm sure that there's big variation among individuals in this respect. I'm mostly aware of that with people whose direct night vision is unusually bad. For instance, people with advanced macular degeneration have no direct vision whatsoever (night or day), but can still see quite well with averted vision. And my wife swears that she can't see any galaxy except M31 with direct vision, but she can see plenty with averted vision.
This extremely small sample leads me to think that there's more variation in direct vision than averted vision. Maybe your direct vision is unusually good, and that's why you don't notice much difference.
It's also possible that you're using averted vision all the time without even being aware of it. That's certainly the case with experienced deep-sky observers. I have to make a special effort to stare at things directly to find out what they look like without averted vision.
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Tony Flanders
eyeglasses
6x15 and 8x32 monoculars
8x25, 7x35, 10x30 IS, 10x50, and 15x70 binoculars
70mm and 100mm achromatic refractors
4.5", 7", and 12.5" Dobs
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kaaikop
sage
Reged: 07/13/08
Posts: 467
Loc: Ste-Therese, Canada
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Quote:
I'd suggest looking at the Blinking Nebula, NGC6826.
Using my averted vision, I read: Bikini Nebula 
Oh, maybe that's my perverted vision (Sorry!)
Seriously, for me, averted vision is looking anywhere else than directly at the subject.
Like everyone says here, it is just a very faint improvement, but it works
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Benoit, RASC Montreal
-C 9.25XLT on EQ6 Pro / ED80SF on Portamount
-Plossls, Radians, Naglers, LVW's & Orthos.
-a pair of 7x50's
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zee
super member
Reged: 07/04/07
Posts: 134
Loc: Arizona (varies)
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Yes, DSOs are my favorite objects, nebulae and globs and faint galaxies especially.
And thanks all! Great information. I'm thinking now that I was expecting too much, and it may be that I am using A.V. without thinking consciously about it. We imperfectly sighted people probably have all sorts of unconscious tricks we developed to function with our limited sight; this may have been something I've been doing for so long I do it automatically.
Part of the problem with my expectations is that someone told me that w/direct vision, they could see maybe 12 stars in the Pleiades and w/averted, naked eye, 40 or 50. I was thinking, gosh, I may only see that many at 50x with my dob! Perhaps they were full of shhh -- er, wishful thinking.
And I will try everything suggested, the blinking nebula, the globulars (which I like anyway--it'll be fun to have a glob night this week to try out that test), and I'll practice more regularly again now that autumn has arrived.
I do get improvements steadily in what I can see, and those seem to be stair-step improvements, not gradual. Months will go by, and one night, I can suddenly see structure in something that had looked like a faint blob to me several times before; once I have seen the added detail once (which might be from practice or an unusually good night of seeing, I've never been able to decide), I seem to keep it on most subsequent viewings.
Again, many thanks for your help.
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8" Orion classic dob
15x70 Celestron Skymaster
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star drop
Guilty as Charged
Reged: 02/02/08
Posts: 3297
Loc: Cattaraugus Co., NY
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Quote:
Part of the problem with my expectations is that someone told me that w/direct vision, they could see maybe 12 stars in the Pleiades and w/averted, naked eye, 40 or 50. I was thinking, gosh, I may only see that many at 50x with my dob!
At times I have seen 12 or so with direct vision. Averted vision only adds at the most six additional stars and that is very dependent upon sky conditions. The fifty percent increase in stars detectable sounds good but in reality it is only a few tenths of a magnitude increase at best.
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Ted
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Carol L
Reged: 07/05/04
Posts: 5880
Loc: Tomahawk, WI 45N//89W
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Quote:
Any additional advice?
Just a thought.. do you see things better when your eyes are rested?
My astigmatism acts up when my eyes are tired and nothing's quite as good as it normally is. 
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 *Step-by-Step Lunar Sketching*
CN Gallery
Photo Gallery
8"SCT ~ 120achro ~ 90Mak ~ 80ST ~ 11x70s ~ 22x100s
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kroum
super member
Reged: 08/28/08
Posts: 166
Loc: Bay Area, CA
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You might also while using averted vision is to move your eye around. What I do is instead of staring at one spot next to the DSO I'm looking at, I keep it on one spot for a second or two, then look in a slightly different spot, or just keep circling around and/or darting back and forth. That (atleast for me) seems to help catch a wee bit more detail. This works especially well in my light poluted back yard if for instance I know I'm in the right place, but don't see the object, I'll look all around, and it will usually pop out. I guess it's the same idea as tapping your scope to make the view jiggle a little. (but that bugs me )
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Tony Flanders
Carpal Tunnel
Reged: 05/18/06
Posts: 2102
Loc: Cambridge, MA, USA
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Quote:
Someone told me that w/direct vision, they could see maybe 12 stars in the Pleiades and w/averted, naked eye, 40 or 50.
I am exceedingly suspicious of that claim. Relatively few people can see 12 stars in the Pleiades at all, though it's certainly not exotic. In fact, almost everybody can see mag-6.5 stars in a dark sky, and there are more than 12 Pleiades stars brighter than that. But the problem with seeing lots of stars in the Pleiades is that they're all crammed so close together, not that they're faint. In other words, acuity not sensitivity.
Now averted vision is famously bad at acuity, so I find it hard to imagine it greatly expanding the number of stars people can see in the Pleiades. Moreover, 40 stars implies a limiting magnitude around 8.5, which is about the most that I've ever heard claimed by the most eagle-eyed observers in the best conceivable conditions.
Finally, I for one find it incredibly hard to count stars that I can see only with averted vision. (This is why I absoloutely despise doing limiting-magnitude estimates.) Since the stars go away when I look at them, it's almost impossible to pin down their locations and check them off on a list. So I can imagine somebody getting to 40 or 50 just by counting the same old 12 stars multiple times.
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Tony Flanders
eyeglasses
6x15 and 8x32 monoculars
8x25, 7x35, 10x30 IS, 10x50, and 15x70 binoculars
70mm and 100mm achromatic refractors
4.5", 7", and 12.5" Dobs
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Carol L
Reged: 07/05/04
Posts: 5880
Loc: Tomahawk, WI 45N//89W
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Quote:
(This is why I absoloutely despise doing limiting-magnitude estimates.)
You too? Evidently my estimates were always too weak and I came under fire a number of times for having 'averted imagination'. Apparently I was seeing things through the eyepiece that were "not humanly possible"  according to my estimates, so I decided to totally drop the NELM and simply go by what was seen through the eyepiece.
It's quite easy to include (and mark) the faintest averted star on my sketches and then check the magnitude in the Sky Tools program. Works for me.
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*Step-by-Step Lunar Sketching*
CN Gallery
Photo Gallery
8"SCT ~ 120achro ~ 90Mak ~ 80ST ~ 11x70s ~ 22x100s
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mikiek
scholastic sledgehammer
Reged: 10/10/07
Posts: 925
Loc: SE Texas
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Agreed - most people have an area of the outer retina that is most sensitive. For me looking down and to the right of a target is the best location for AV. This puts the most light on the upper left of the ring of rod receptors.
You can either center the target and look around it or keep your line of sight centered and move the object(scope) around. I have the best results moving the target slightly above and to the left of center.
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___________________________________________________________
May there always be starlight on the path - R.Burnham
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Celestron CPC 1100
Radian 3mm, 5mm, 8mm, 12mm
Panoptic 22mm, 27mm, 35mm(the brick), 41mm (the cinder block)
Nagler 3-6 zoom, T4 17mm
Ethos 13mm
Everbrite Diagonal 2", Powermate 2X
FeatherTouch Crayford, Microfocuser
Telrad Finder, SV 9x50 RACI
Kendrick Dew System
TV NP-101(riding the CPC)
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RussL
Music Maker
Reged: 03/18/08
Posts: 1609
Loc: Cayce, SC
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Hi zee,
Your mention of seeing "snow" at night interested me. I also have astigmatism and wear glasses for it and near-sightedness. And my night vision isn't what it used to be either. But something happened one night that was disturbing to me. Tell me if this has happened to you. I was looking way up near the zenith naked eye, trying to pick out a faint constellation in my polluted sky when I thought I could just barely see one faint star, as if with averted vision, except that it also seemed as if I was looking directly at it. Then, it disappeared. Still craning my neck and looking a little to the side of that spot, I saw it again, and again it disappeared. Then, another one appeared just to the side and disappeared. Then, another. I began to look carefully at these apparitions and noticed that they weren't exactly stellar, but just a bit fuzzy, but very nearly like what a faint star would look like while using averted vision. After a minute, I looked back down, waited a couple of minutes and looked back up. Nothing. But then after about ten seconds they started appearing again, making me think I was seeing dim stars where there were none to be seen. Confusing when you're trying to find something. It only happens when I'm straining to look very high. I assume it has something to do with restricted blood flow while looking up, or perhaps I'm developing some blockage in my carotid arteries. It doesn't do it all the time, but I have seen it since and I am wary of it. It certainly can affect my averted vision, making me think I'm seeing things that aren't there. Kind of the opposite of your problem, but it just goes to show that there can be many variables in our vision.
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--Russell
"Akita mani yo." Observe everything as you walk. (--Lakota)
Celestron Celestar 8 Standard SCT, f10
Celestron 80mm Wide View ref., f5
Criterion RV-6 Dynascope, Newt., f8, (c. 1962)
Sears Discoverer 60mm ref., f7, (c. 1973)
Celestron Ultima DX 10x50, 6.5 TFOV
Tasco 7x35 wide
Several mediocre eyepieces
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zee
super member
Reged: 07/04/07
Posts: 134
Loc: Arizona (varies)
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Hey, Russell, interesting. That does sound confusing! I've never noticed that phenomenon for myself, no.
I don't know what it might be from--though I have read that seeing a field of "snow" as I did as a young person as we age is a bad thing, a sign of one of those eye diseases like macular degeneration or RP or I forget which one. It's interesting to think that because we astronomers pay so much attention to every little detail of what/how we see that we might catch a medical problem much sooner with its first subtle signs. I hope that's not the case for you, of course!
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8" Orion classic dob
15x70 Celestron Skymaster
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RussL
Music Maker
Reged: 03/18/08
Posts: 1609
Loc: Cayce, SC
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Thanks, zee. I also notice that my vision is weird after looking at the computer screen too long, but that's probably a common trouble with everyone. I guess my "spots" may not be unlike what you see if you close your eyes real tight for too long or press your fingers against them with your lids down. I guess it concerns me because once in a blue moon I have also had optical migraines where a vessel in the brain has a spasm. But then I don't see spots, but rather something more like a steak of lightning that glows constantly and slowly changes shape and floats off to the edge of view. Interestingly, when it's at the edge I have no peripheral vision. Sheesh, getting old is scary sometimes. 
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--Russell
"Akita mani yo." Observe everything as you walk. (--Lakota)
Celestron Celestar 8 Standard SCT, f10
Celestron 80mm Wide View ref., f5
Criterion RV-6 Dynascope, Newt., f8, (c. 1962)
Sears Discoverer 60mm ref., f7, (c. 1973)
Celestron Ultima DX 10x50, 6.5 TFOV
Tasco 7x35 wide
Several mediocre eyepieces
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RandyR
Enginerd
Reged: 04/01/04
Posts: 14076
Loc: Castle Rock, CO 6677' MSL
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I think what many people report as 'drastic improvements" when using averted vision, may be more of a case of "averted imagination"...
You need to look just SLIGHTLY to the side of the intended object. The big concentration of rods (your night vision tool) is JUST BARELY off center from the center of your retina.
You might want to seek out a good Opthalmologist (not an Optometrist), and schedule an appointment to discuss your specific vision conditions and peculiarities. We all have some differences, a good Optho can check you out and advise you on how to best use what you have.
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"Dark Skies & Great Viewing"
RandyR / NQ0R
GPS 9.25 XLT/Sky Align /FeatherTouch
TV85 w/FeatherTouch
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