A new era has "dusked" for me here at Astro.Geekjoy. "Jeff the wordsmith" is now becoming "jeff the human astrograph". Eyepiece impressions, once a sideline to my main astronomical aspirations, are now taking center stage. I've finally mustered enough patience to settle beside one or the other scopes, take pencil and paper to hand and "draw it as I see it". This on a more or less regular basis...

As you might imagine, sketching the heavens is not something one should take lightly. To set yourself up as an artist is a sacred charge. Certain commitments are assumed. Accuracy, verisimiltude, and integrity are essential to achieving satisfying results. One must also listen to that subtle inner voice which says, "It is finished". To all of the above I make no especial claims. I know there are inaccuracies in the sketches. I am after all human - not a camera!. I know that it would be difficult for anyone to say "Oh yah, that's definitely M31!" Thus complete verisimilude is also at question. But, I do know when to quit!

In rendering, I also take risk that others will draw incorrect conclusions regarding Argo and the Pup. For instance, someone may count 55 stars in a sketch of the Pleiades and say "Why I have an 80mm scope and I can clearly make out one-hundred forty-three!" What they miss is the fact that the sketch was made with the Pup stopped down to 57mm (in order to map against another related astro.geekjoy project - DSO's by Optimal Aperture.) They may also miss the fact that telescopic limiting magnitude is determined by magnification, seeing stability, and transparency. They may be unaware that I avoid including stars seen with averted vision...

Speaking of DSO's by Optimal Aperture, I have a little secret to confide in you... By drawing studies through the optimal scope aperture, I will never be put in a position where I am sketching things too complex or sophisticated for my hand and eye. Why? Because by using the least aperture (that gives the essentials), the view never gets too involved...

If I were to attempt a drawing of the Great Nebula in Orion through Argo, the amount of detail would be staggering. I could never hope to get it right! But through the 57mm Pup, the Great Nebula's essence is approachable - its shape, frontier, background stars, etc.. This without having to have superb drawing skills or spending mucho time at the eyepiece!

So dear reader, as you follow this (and future reports along the lines of "jeff the astrograph") understand that there will always be errors, inaccuracies, and a lack of verisimilitude. BUT you may at least get an impression of what is seen by human eyes under the direct tutelage of photons from the Great Beyond.

This particular report covers two evenings out and about. Friday evening, February 1st and Saturday the 2nd. The main theme is "eyepiece impressions" using optimal apertures through the nominally 80mm Pup. However, I do go on to mention other items of interest. This is my preogative. I am essentially keeping a journal of my astronomical research and adventures. As I do so, you are welcome to come along for the ride...

Friday evening February 1st, started early. Within half hour of sunset had the Pup's meagre 6x26mm finder sighted on Polaris. Another fifteen minutes and Polaris-B could be seen at 75x - under aversion. Pulled my eye out of the field to track down The Gemini Twins (Castor and Pollux) unaided. No problem. Centered on Castor with 43mm aperture stop in place - 75x resolved it cleanly. 36x could not. (Based on this, The Double Star Separation Calculator suggests the pair is now separated by 4.0 arc seconds. Since sepcalc doesn't support 43mm aperture, I had to interpolate...) The series of observations done early in the eveing was devised as a check against information included in astro.geekjoy's hypothetical Messier Marathon. (See Messier Year In a Night - the basis of a book that may be published to help fund a hoped for Astro.Geekjoy observatory.)

Having validated this one concern, moved to the next - Iota Cassiopaeia. At 140x caught 7th magnitude Iota-B on or very near, the first diffraction ring of 4.7 magnitude Iota A (itself a close binary requiring adaptive optics for resolution). Within an hour of sunset could make out the 12.5 magnitude field star on eye movement. As such the Pup - at 80mms - was holding stars down to magnitude 11.0 at its highest useable magnification.

NOTE: Iota Cass field sketch at left was done at the eyepiece of 150mm Argo Tuesday evening, January 29th at 120x under 4.5 ULM and 7+/10 stability conditions. The 12.5 magnitude field star (north-northeast of the triple) required slight aversion. According to The Telescopic Limiting Magnitude Calculator, stars to magnitude 12.0 could have been held direct through Argo under those conditions.

Meanwhile, Jupiter had entered the skies middle third. Took the time to characterize how Jupiter looks through the Pup at various apertures - 43 / 57 / 67 & 80mms. Repeated the same series on February 2nd, under better 8/10 stability and darker skies (5.0 ULM). Its that series that I choose to report instead: Amazingly, all four apertures showed the NTB - but at 43mms the planet was quite dim (.3mm exit pupil). Both 43mm and 57mm gave nice sharp edges with excllent color correction and good depth of field. 67mm provided superb illumination, and only the slightest magenta tinge. This was the aperture of best image contrast. 80mms was overbright, soft, and displayed marginal chromatics. 80mms showed everything 67mm did - but the eye had to work harder.

On that same occasion (the 2nd) caught an Io transit. Watched through all apertures as the Galilean ingressed and remained visible - even after passing completely into the planet's margins. Again 67mm made it easiest to follow the ingression. This continued for about ten minutes until I lost the satellite's dull disk against the SEBs. On this occasion, also inpsected the other Galilean's: Ganymede's disk visibly larger than the others. This however was only possible beginning at 57mms. It is a well established fact however, that airy disks sizes vary with magnitude - especially in small aperture scopes, so it is unlikely that the Pup at any aperture could "resolve" a Galilean.

NOTE: The sketch of Jupiter at right was done through 150mm Argo on April 9th, 2001 at 180x under 5.0 ULM transparency and 5/10 stability. By mentally adding an ill-defined, but definite NTB just below (the dark) NEB, and throwing in a little spurious coloration (violet-brown), you can get an idea of how Jupiter looks through the Pup under 8/10 stability conditions. Notice also the vague "thinning" of the SEBz. This appears through the Pup as well - but requires 67mms minimum aperture.

On both occasions, (on the 1st and 2nd) viewed Saturn. Of course, the presentation on the 2nd was superior. Could follow a pencil thin Cassini almost to the planets limb - both on the anterior and posterior sides of the globe. This was possible at 140x using either 67 and 80mm's. On that occasion, Cassini could just be detected at 43mms. Like Jupiter 67 and 80mm's gave the best views. Unlike Jupiter, the 80mm view was not "washed out" by excess illumination.

NOTE: The Saturn sketch at left was done at the 210x eyepiece of 150mm Argo on Tuesday, January 29, 2002. Transparency was roughly 5.0 ULM and stability 7/10. This view almost duplicates that seen through the Pup at 80mms with the exception of an MIA Encke Minima and resulting truncation of Ring A. Detail was not quite as distinct on the globe itself, but posterior shadowing was obvious on Ring B. Blue gray mottling seen in the SPR, but not the gentle shadings seen in the sketch at 150mms.

In observing both Gas Giants - and Jupiter in particular - I experienced something that should be articulated. There is a certain shift that occurs in the eye when either planet truly sharpens up. It is as though, for a few moments, the planet's globe (or ring system) becomes exceedingly finely etched and background space appears a "still pool" of deep, clear and unreflecting water. This sensation is often achieved with 150mm Argo - but only recently through the Pup. Frankly, the experience is quite sensuous and trancendental. It may, in fact, lie at the root of why so many amateurs observe these two planets with fervour. Such a view could be the "Holy Grail" among scopists. And explains why the optical illuminati are so bent on possessing and using only the finest optical equipment...

By 90 minutes after sunset on the first of February, skydark descended and I could hold stars to magnitude 4.8 overhead. It was then that I shifted to sketching in earnest. My first deepsky study would be an "optimally-correct" view of M31 - The Great Galaxy of Andromeda.

Even through 57mm's of stopped-down aperture, more detail is possible in M31 than any other galaxy visible from the northern hemisphere. In the sketch at right, the 25mm Ultrascopic with 3x barlow is used to get a full one degree field at 48x. At the eyepiece, both the southwestern and northeastern spiral arms could be seen to extend (faintly) to the very edge of the field. The northwestern frontier was clearly more delineated than southeastern. The galaxy's core quite intense and starlike. The core region could be seen to elongate toward the southwestern spiral arm. At a full 80mms, the galaxy brightened perceptibly and its spiral extensions could be traced easily to the limits of the field of view.

M32 (due south of M31 core) was easily identified at 48x. It showed a bright star-like core and fuzzy core region along with slight elongation due south (on aversion). M110 (northwest of the core) lay outside the field of view - but appeared quite diffuse and could easily have been missed at 57mms without careful inspection.

Sketching the M31 region took perhaps 30 minutes. Over that time the sky darkened perhaps another .3 magnitudes. Upon its completion, I felt exhilerated. After taking a deep breath, moved on to my next "optimally correct" study...

The Perseus Double Cluster is a spectacular study in just about any scope. Three inches of aperture gives the full impact of "cluster" by sprinkling numerous faint stars throughout the field. The sketch (at left) was done at the 48x eyepiece of the 80mm Pup under 5.0 ULM conditions. Stability was very good and member stars shown like tiny luminous jewels against an ebony sky. Both clusters easily fit the 1 degree field. A barlow was used to run up the magnification. This helped maintain the excellent eye relief of the 25mm Ultrascopic eyepiece - something especially appreciated while sketching...

Took some time off to scan the two images into the computer - and allow Winter's Celestial Hunter a chance to culminate. The scope was left out back. Little did I know that - even though all caps were installed - the object glass had dewed over. This, plus the 50mm handicap imposed by The DSO Susceptibility Calculator, would ultimately invalidate the image at right. For you see something needful was missing - "The Eagle Obscuration". This critical level of detail (along the northeastern frontier) was only visible on eye movement. So the next night - after "sun-dogging" the Pup - I revisited the region and modified the sketch to achieve the the following revised image:

This sketch clearly shows the light background glow east of the "Eagle" that makes it perceptible. If you look at actual astrophotos of the Great Nebula, you will not see an "obscuration region" as depicted here. What you will see is an extensive and dim "pinkish" glow not visible to the eye through most amateur equipment. Meanwhile, the bright reflection regions of M42 and M43 can be clearly seen sandwiching the obscuration. Seeing the Eagle in mid-flight is one of the most extraordinary aspects of the Great Nebula - and the part of it that is actually lost in photos and CCD images. The Great Eagle of Obscuration is an essential part of any "optimal view" of this most spectacular deepsky delight.

I also revisited M41 on the 2nd - knowing that it too was tainted by dew on the lens. Surprisingly, there was little difference except for one fact: The "twin-tusked scarab" shape was more apparent than on the previous evening. As I recall, the scope was setup for 36x observation at the time and not the 48 of the previous evening...

M41 in Canis Major is classed as a three inch study - but the sketch at right barely gives the cluster its full due. Though culminating, M41 lay well down into a region of visible irradiation (caused by a rising third quarter Moon). As a result, some of its fainter stars were only seen on aversion. Sketch made at the one degree field 48x eyepiece through the F5 achromat's full 80mm's of aperture.

One goal of Saturday the 2nd was to sketch the region of reflecting nebulosity known as NGC 1971-5-7 and capture the brightly scattered cluster NGC1981 in the same region. This was accomplished after retouching the M42 sketch and before verifying M41 in Canis Major.

The region sketched at left lies due north of the Great Nebulae of Orion. In fact, had I used 36x instead of 48, I could have included M43 and parts of M42 in the image. The nebula enshrouded open cluster NGC1981 is seen at center in the field. Wasn't sure there was supposed to be any nebulae visible, so checked the region through the Ultrablock nebulae filter. The most concentrated region of nebulosity is seen southeast. This nebulosity (presumably NGC 1973, 1975 and 1977 - vintages), was obvious to my eye and showed a perceptible luminosity gradient. Despite this, I rather doubt the reported integrated magnitude of this 10 by 20 arc-minute region (5.0). My best guess is magnitude 7 cumulative. This suggests that the optimal view would be given through a 100mm scope under 5.5 ULM skies - rather than through the 57mm aperture stopped shortTube Pup at 5.0 ULM of the evening...

After rendering the above sketch, made a check of Alnitak. At 140x, could hold the 9.5 mag 1 arc minute come direct. 4th magnitude Zeta-B was a bit tough - but distinguishable. Made a check of beautiful blue-white Rigel - no sign of its 9 arc second 8th magnitude secondary.

Turned the Pup on Sirius which gave a stupendous star test. Intra-focally only the faintest discoloration and along with beautifully concentric fresnel rings. Extra focus was almost as well sculpted - but far more chromaticism apparent. Determined that the central star seen extra-focally fluxes through a variety of colors. Begins white and ends up red before extinguishing. Outside rings - both sides of focus - are of more or less equal dimension and brilliance at similar defocus. Unfortunately they are not perfectly round due to the scopes lack of precision collimation mechanism...

As the sky darkened Saturday, began the sketch of M45 at right. This through the "optimally-apertured" 57mm Pup. Found that the 35mm Ultrascopic eyepiece and 3x Ultrascopic Barlow (36x) were just able to frame the entire cluster. Enjoyed watching the faint stars come out to play as skydark approached. By ULM 4.8, quite a bit of "nebulosity" was present. But since the sketch was strictly about the cluster, and no part of the nebulosity stood independent of the brightest Pleiades members, elected not to include it.

Finished up Sarurday evening devoting quality time to Jupiter. It was at this time that I caught the Io ingression. Had to break off around 10:30 due to an AstroChat commitment. Wasn't there for actual "shadowfall" on the SEB...

Yes, ladies and gentlemen, I do seem to be taking this "eyepiece impression" stuff in stride. But I will never become really good at it. After all I'm your basic "optimal aperture" kind of guy. To become really good at some one thing, you have to place far too much of time and attention on it. Necessarily, other things must fall by the way side.

Speaking of which...

The Ageless Jazz Quartet TAJQ: Brookdale Lodge Brook Room, Brookdale California, Sunday Evenings 5am - 8pm. Drop bye sometime. Have a nice meal. Enjoy the ambience. Share a bottle of wine with someone near and dear. Applaud with enthusiasm. Then tell me about your...

Clear and Steady Skies!

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