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I still find that I don't trust my own eyes to the extent that I probably should.

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Faith --

Sometimes when a galaxy flips orientation I've been able to nail it down to elongation in one direction in averted and in another direction in direct. I believe this is usually the result of a brighter bar in the direct-vision direction with dimmer arms elongated in the other direction.

Of course, other times it just flips randomly.

Anyway, here's and example of one which flips uniformly going between averted and direct:

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Arp12 NGC2608 1/23/2009 21:11 UT; Pickering 3, NELM 5, SQM 20.3
400mm Mak-Cass @ 235X

Mostly just a smudge with a semi-stellar core and nondescript elongation. However, after considerable study it becomes apparent that the elongation flips 90° between averted and direct vision, suggesting a bar running NNW-SSE and a halo running ENE-WSW.

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I still find that I don't trust my own eyes to the extent that I probably should.

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I'm not sure I understand what the problem is here.

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Who said there was a problem? Jeff's posts do a really nice job of illustrating the reality that detections of objects at the threshold of visibility are as tenuous as one would expect of observations made at the edge. His posts also illustrate the benefit of experience. Over time--and this is something that can only be gained with time at the eyepiece--an observer gains an awareness of where his threshold of reliability lies. And as one's observing skill develops, that threshold can be lowered. A few of the most experienced observers I know can reliably trust detections in the 10% to 20% visibility range. Personally, I'm more comfortable in the 30% range. Another bit of helpful information Jeff's posts impart is the value of sketching as a tool for confirming threshold detections. A sketch serves as a detailed record of an observation and can be compared to a CCD image of the field to confirm the accuracy--or the inaccuracy--of that night's work. Finally, I applaud the implied message in Jeff's posts that it's OK to make and acknowledge an erroneous observation. Every seasoned observer has a few Big Foot sightings in his log book.

Novice observers should learn to appreciate this aspect of the hobby. Expressions of skepticism toward a threshold observation are perfectly natural. More than that, in instances where an observer tosses off a claim of detection of a notoriously difficult object without offering details of the observation, skepticism is an appropriate response.

Bill in Flag

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Grand Canyon Adventure
Lowering the Threshold

18" Obsession
4.5" Meade 4500
10x50 Swift Audubon

Cosmic Voyage

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While we're discussing averted imagination, one trick I use is to put the object I'm hunting out of the eyepiece, and do a 'staring session' at a blank area. If I see similar flickers of the eye there, then I know that the observation is suspicious.
Any others also do this?

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While we're discussing averted imagination, one trick I use is to put the object I'm hunting out of the eyepiece, and do a 'staring session' at a blank area. If I see similar flickers of the eye there, then I know that the observation is suspicious.
Any others also do this?

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M95 NGC3351 3/23/2009 23:00 UT; Pickering 4, NELM 5.5, SQM 20.5
400mm Mak-Cass @ 153X

Very difficult to get anything more than a semi-stellar core swimming in a circular disk under these conditions. I spent about an hour, using everything from 70X up to 330X, with and without a Deep Sky filter at the larger exit pupils. The higher light densities probably worked a little better, but there wasn't much between them. Sometimes I felt the Deep Sky was helping, but never enough to nail down any detail. I finally took a break and sketched M96 before coming back to this one.

In the end it was motion that brought out the bar. Jiggling wasn't really helping, but slewing the whole field back and forth at 64x-sidereal provided the most conclusive information. I tried slewing in both axes, and rotated the diagonal to change the image orientation to make sure I was picking up actual detail instead of eye/brain-induced artefacts. Still got just the bar; no ring.

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And indeed, there was yet another technique in that one (as suggested by Lard): sometimes you need to take a break.

Cheers,
-- Jeff.

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Nikon 18x70s / UA Millennium                                       Colorado:
Solarscope SF70 / TV Pronto / AP400QMD                       Coronado SolarMax40 DS / Bogen 055+3130
APM MC1610 / Tak FC-100 / AP1200GTO                        Tak Mewlon 250 / AP600EGTO

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in instances where an observer tosses off a claim of detection of a notoriously difficult object without offering details of the observation, skepticism is an appropriate response.

Bill in Flag

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One phenomenon that I've seen repeated again and again and again is that of the smaller apertures outdoing at times larger apertures on stellar objects.

The fact that a given telescope has a larger aperture than a nother telescope at times isnt the clean visa to fainter stars that one would expect. The trouble with the larger scopes is they all too often reveal stars as bloated distortions with nary a diffraction ring in sight. Though it SHOULD be smaller, its often disappointingly smeared to a great extent. Not the mirrors fault, just the atmosphere.

The lesser aperture - even by half often excels at producing a more proper diffraction pattern. ITs neat , tight and small and thereby has its contrast against a dark sky at an optimum no matter how faint it is. O'meara seeing the central star [M57] through a 9" refractor or pluto through a 4" refractor is testament to O'Meara certainly, but the fact is these instruments were able to be ALLOWED to produce text book stellar or stellar-like images.

On extended objects like galaxies the textbook advantage drops away and greater aperture reins like the king it is.
On fainter stars or star-like points of light, the smaller scope will often bely its own size in comparison to greater objectives.

Having said the above, I'm not stating this is the staus quo.
I'm saying under certain conditions the smaller aperture will allow itself to outdo whats normally expected of larger aperture. On truly pristine nights, when even a 20" can atleast be NEAR its diffraction limit. Then you'll see some serious magic happen with the 20.

In closing, while its wonderful that a lot of astronomers among us get out and even have the chance to observe through observatory size scopes, it often reeks more of the state of the sky that night and nothing more if it was invisible. When the sky is at least decent, those same scopes [I'm recalling the 81"] will allow direct vision of M57's central star as posted by some one recently who had the great opportunity to look through it.

Pete

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One interesting upshot of this is that I'm overly conservative: there are no galaxies (which is what I was hunting for) in the sketch which turned out to be stars. But there are quite a few stars which turned out to be galaxies.

-- Jeff.

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I incline the other way and tend to give myself the benefit of the doubt 'cause at least some photons hitting my eye must be from a DSO. I used to wonder why the M81 I saw in my binocs didn't point at M82 as it did in the finder map - then I saw them through a sope and realised there was a faint star just below M81 that I had previously been blurring in.

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One phenomenon that I've seen repeated again and again and again is that of the smaller apertures outdoing at times larger apertures on stellar objects.
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Under seeing, do you mean transparency?
'Cause I've seen some pretty dim stuff when the seeing's been abysmal.

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