by Jeff Barbour
True Spring is very close to overthrowing a mostly overcast Santa Cruz Mountain winter. The air is perceptibly dryer, warmer, and the usual batch of evening roll-in clouds are finally dissipating. Despite improved conditions, fellow SCAC amateur Dan (of Takahashi FS102 fame) and I (of no real fame whatsoever) decided to take a "road trip" to Fremont Peak State Park. This on a night when we would ordinarily observe with the fine fellows of SCAC at the Bonny Doon observing site...
The Peak itself is a winding country road run west of San Juan Bautista, CA. Our trek included about an hour and a half of "road" time. Leaving Santa Cruz around 4:00 PDST, we didn't really arrive at the Peak until 6:30. Along the way we stopped over in San Juan Bautista for some excellent Mexican cuisine. Once well-reinforced with an abundance of protein, fats, and carbohydrates, we made the ten mile long, half mile climb up the mountain. There to park in the Coulter Picnic area.
Our first major decision was where to setup. (Choosing our evening meal had been childsplay.) Adjacent to the Coulter picnic area is a parking lot with expansive view to the west. A much lowered Sun shown brilliantly. We looked back on the plentiful high thin clouds that populated the sky over the Monterey Bay. On the drive out from north of that same region, the sky above Fremont Peak had shown similarly - if less densely. Overhead we could see variagated high thin clouds floating like seawaifs in an ocean of silvery blue.
In the end we decided that there was just too much in the way of southern and eastern restriction from the parking lot locale. Returning to Dan's pickup, we agreed to observe from where we parked - a location that more or less coincided with previous visits to Fremont Peak by self and family.
Like every visit to Fremont Peak personally experienced, Dan and I had complete freedom in choosing precisely where to setup our scopes. Once again, not another single amateur observer was in sight. Again I say, the Peak ain't what it used to be...
The hour was still early. Once decided where to setup, there was no rush to actually do so. Dusk lay an hour or so in our future. The equipment was secure in the truck. We set off afoot to the FPOA observatory.
As many of my readers know, the Fremont Peak Observers Association has a unique relationship with Fremont Peak State Park. The Park had embraced the theme of being a "dark sky sanctuary". A place where Lovers of the Night Sky could "Night Trip" to sit at the feet of Nuit. Somehow, and as the result of the hard work and imagination of numerous persevering amateurs and that of an equally committed Park staff, the FPOA had established a "Temple to the Night Sky". This particular temple includes a well-wrought volunteer-constructed observatory building, with ATM-built thirty-inch short-focus truss tube newtonian reflector. Dan and I hoped to visit the observatory. That was the immediate goal before us.
The gate to the observatory drive was locked but a footpath neatly circumvented it. Clearly "walk ins" were not discouraged. Not just anybody could drive up to site. In fact later that evening, we found that FPOA members were entrusted with the "secret code" needed to gain admittance. That code was not in our possession...
The driveway to the observatory led past the ranger's domicile. In fact the Ranger in Charge conversed on a cell phone as we approached. We caught his attention long enough to shake hands and learn that the observatory would be open for the evening. - I could almost hear Dan's inner lips internally smack - or was that my own?
The very first time I visited Fremont Peak, the Ranger in Charge (Ranger Rick) was vacating for a larger park in the same part of California. Ranger Rick and I had a long conversation at the time. His commitment to the Peak's role as Night Sky Sanctuary was obvious. It was just as obvious that the young fellow who now oversaw the peak (a shared duty with another naturalist) placed his main interests elsewhere.
Parting amiably, Dan and I continued our saunter along the drive. There we came across a father and son setting up a Losmandy G11 mount. This gentleman (Dave) was very friendly and open. A true tribute to our High Art and Science. I salivated as Dave explained that he would be mounting an AP155 StarFire APO. We talked about the incredible Gas Giant views expected of such a scope. We also considered its deepsky reach - comparable to that of an 8 or 9 inch SCT. Dave said that 14th magnitude stars lay within his reach, and that during galaxy comparos with 8 inch SCTs, the Big APO got the nod in both contrast and structural detail.
Have I ever mentioned that I love APOs?
Dave seemed suitably impressed when Dan and I described our equipment. A Takahashi FS-102 is by no means a "toy scope" and the Intes MK-67's bears a well-deserved reputation as probably being the finest scope available for under $1K. Dave said he planned to observe most of the night. Dan and I expressed "some little" enthusiasm for a looksee through the 155 once we finished our own evening of observations...
After thanking Dave (and giving the nod to his young son), we continued our walk. Soon thereafter, we encountered a second amateur well advanced in the setup of an 18 inch Obsession. Sadly this fellow showed no real enthusiasm for chatting with us. Strangely though, when an older gentlemen walked by (Rick by name) he was greeted with wild abandon. This concerned me. And I'll tell you why. Dan and I had just witnessed a form of personal chauvinism. We are all God's Children - besides, you never know when that pair of strangers you encounter may actually be "angels walking among men". Now, of course, Dan and I are not Angels - but we could have been. And in brushing us off so easily - should we actually be devils, his life could have been made much more complicated...
So shaking the dust off our sneakers, Dan and I proceeded further up the drive. The observatory was clearly in sight and several small scopes were in process of setup. The air about the place was one of quiet, unhurried diligence. I liked the scene, we would be welcome here. And of course, with my "labrador retriever enthusiasm", I busted in on things with wildman abandon. The scene's solemnity was quickly banished. Dan and I began checking out the "Big Eye" and derailing the intentions of FPOA-member Don who was unhurriedly finishing the task of scope preparation.
Our first impression was that of the massiveness of scope and mount. Huge and equatorial. This scope and on this mount, was a beaut. And Don was most willing to talk with us about the scope and the way business was conducted on public nights. At dusk, there would be a public presentation. At skydark "let the viewing begin". There was to be no really "planned study program". The operators were open to suggestion - or would, lacking same, pull stuff out of their hats. I liked the concept. It is not one I personally follow, but it worked well given the clientele...
I noticed a PC monitor in the corner of the room. Don explained that, yes indeed, it was used to automate scope orientation. All he need due is meticulously move a crosshair cursor over the monitor screen and the scope would follow in real time. Given the fixity of the mount, little was necessary in terms of calibration - other than the occasional "fine tune" during the course of the evening. In fact, not only could the scope be navigated automagically, it could also be easily nudged during the course of observation to sweep for details. And such sweeps were almost imperative! The field of view at lowest power (200x) amounts to about 10 arc-minutes, Thus, to take in the entire M31 galaxy would require numerous such nudges against the mount's slip clutches.
Of course, Dan and I learned much more about the scope and its use. For instance, several observers had done the kind of "soft science" posted on astro.geekjoy.com. Disparate double stars (especially doubles with 12th and 13th magnitude companions) had been resolved - along with a few close toughies (Gamma Andromeda for instance). Don also explained that the optics on the scope were fully diffraction limited and that an eight inch off-axis mask was used for planetary work. We also learned that all five Uranian satellites had been resolved. During the last opposition, Phobos and Deimos were detected in the company of Mars. Finally, and surprisingly, the dimmest star held by the scope was of the 16th magnitude - a value easily achieved by any scope of two-thirds the aperture under optimal dark-sky seeing conditions...
Dan and I were told the observatory would be open through the early morning hours and made plans to put our stuff away around midnight. We would then return for some "quality time" with the "big 'un". On exiting we wandered over to visit with a youngish blonde lady who had just finished setting up a 7 inch Mak-Newt. Our conversation with her, and her's with others made it clear that this particular women was well-established in the astronomical community. It was also clear that she had many years of observing experience behind her. Right On! Our High Art and Science needs more of the fairer sex among its number. Thank you, whoever you are.
Dan was now visibly anxious to setup. Soon the planets would be naked eye objects and he, for one, wanted to be ready. So we made the walk back to the pickup and began our own setup. I should have sensed something here that I missed. Dan really wanted to get back to look through the other scopes as early as possible. Too bad I missed it. For things did not work out that way in the least...
By the time both scopes were assembled, Jupiter could be seen distinguishing itself unaided well overhead. That first view through Argo at 210x confirmed a sky of good, but less than perfect seeing. High thin clouds threw a bit of light around the planet's well-defined globe. A Galilean had recently transited. A dark barge lay along the NEB about where its trailing shadow might be expected. BUT it wasn't as jet black as Dan and I expected. We concluded it was a barge and that the shadow fell not against the globe. Since the Galilean was extended off the NEB it wasn't Io. The disk didn't look large enough to be Ganymede. It's shadow could be anywhere - and with Jupiter square to our own world, it might even still lay well west of the globe.
Dan's view through the Tak at 150x was comparable in detail to that of Argo's at 210x - and easier on the eye. Again Dan and I agreed. A quality four-inch APO is THE optimal scope for this bright Gas Giant. Why? Because larger scopes have to use much higher magnifications to dim the globe to prevent eye fatique. And higher magnifications mean more stability issues. Now you might say: "Why not a filter?" And I'd say, cause the damn things cause additional light scatter! And now I'll tell you something else. Dave (of AP155 fame) dropped by. He looked through 150mm Argo. "Good view". He looked through Takky "Really Good View!".
Now Argo showed everything the Tak did, that barge and the white oval that trailed it, incursions into the EZ, a darkening on the STB, the STTB etc. But it was so much easier to hold these details through the Tak. And Dave was impressed! In fact on our return to the observatory later, Dave seemed a bit depressed. He had not seen the kind of view of Jupiter Takky had delivered. His AP was already packed away on our arrival and one of the our aspirations formulated earlier - too look through Dave's vaunted Astro-Physics 155mm StarFire EDF remained unfulfilled...
Now before you run out and get one of these babies, here's where Takky lost out. Dan decided to bump the magnification up to 360x on Jupe. I decided to bump Argo to 360x. No comparison. Through the Tak we were afflicted by a lack of image illumination. That lousy flotsam in the eye fluid kept getting in the way! While through Argo - wow, nice relatively sharp image and most importantly no flotsam.
But, its rare to get the kind of seeing where 360x on Jupiter is well-supported. And when that happens, roll over Takky, let Argo take over.
So yo Ed, if you are reading this, forget your 150mm MCT = 102mm APO comparison on Jupiter. It just doesn't hold water. The Mak is clearly superior in detail resolution and contrast at image scale - but you just don't get those 8/10 skies all that often. And that is what had been visited on Dave and his 155. If the sky supported 360x, his view of Jupe would have blown Argo and Takky's out of the optical water.
Dan and I turned our scopes on Saturn. But this is a forgone conclusion. Although the Tak gives a decent view, 150mm resolution of high contrast ring structure can't be beat. I will say this though, under the finest moments of seeing I caught the Encke Minima at the leading ring ansae through the 102, Not too shabby, its there iF the sky is dark enough to show enough of Ring A.
Speaking of Saturn, My, My. Even well descended, both scopes showed spectacular shadowing on the posterior trailing ring. Very fine blue-gray mottling in the SPR. And a well defined SEB. Argo revealed the inner dusky ring quite readily. Now for something very interesting - the Tak could not cleanly resolve the southern frontier of the SEB. Meanwhile, Argo showed it marvelously well defined - how's that for "35% central obstruction"?
Let me speak freely here, unless you live with a scope for a long time. Unless you observe through it frequently and under a lot of sky conditions, unless you compare it with other fine examples of other models and those of differing archetectures, unless you collimate it perfectly and keep it otherwise proper maintained, unless you equip it with decent accessories, you are not in a position to judge, nor make recommendations as to that scopes fitness as an optical instrument. And even then, you are only judging a single example of a breed - not the entire species. Sky and Telescope beware! Your reviewers are not in a position to make judgments regarding telescopes "purchased randomly and unawares" from suppliers. Your writers may do great harm by "weighing whole scope lines in the balance of mercantilism." Think! You, ladies and gentlemen are operating a business and as such can never be the final arbiters of "the Good, the True and Beautiful". Money always, and insidiously, "skews perception".
Both Mars and Venus were also present in the night sky. With Mars at 4.2 arcsecs, there's not much to be said. Certainly some "contrast effect" was possible at 210x. But hey, it's still hanging in there and running the good race. Venus was a chromatic nightmare. Brilliantly gibbously, a tragedy to amateurs. This nearest world to our own, is a treasure-trove of features and detail lost behind omnipresent sulphuric-acid cloudtops. Pity. But who knows, anything is possible!
By 9:00 skydark had arrived, the Celestial Hunter was well progressed in descent. As we bid adieu to well-sprung Orion, we heard the evenly tenored voice of an elderly gentlemen instructing some children in the fine art of celestial navigation. I liked the voice. No doubt, an "elder statesman" of our High Art and Science. By the time Dan and I visited with The Great and Flame Nebulae, he ambled by for a visit. And he was clearly more interested in chatting with us than looking through our scopes.
Bob was indeed an elder statesman. Officer in the FPOA, Project Astro Instructor, and dark-sky preservationist. We talked at length about these and other ventures while turning up the faintish Orion Planetary (NGC2022), glorious M35 open cluster, its coincident and superbly scintillating faint cluster (NGC2158), luminous and well-structured Eskimo Nebula (NGC2392), and a nearby faint open cluster (NGC2420) in sequence. We were stargazing and at the time the sky had reached its peak of transparency. Stars to magnitude 5.5 could be held in the Big Dipper. Each of these fine studies was gorgeous in both scopes. Argo's stars a bit brighter, Takky's background sky a little darker. Nothing new here, old favorites giving splendid views through fine instruments.
During our chat with Bob, I mentioned that several hints had been dropped about our setting up near the main observatory. Bob seemed mindful of the issue, and explained that Park Rules required compliance with the "FPOA" access privilege. Being familiar with the concept of the "Camel's Nose", I understood the necessity.
Once Bob departed, Dan and I took in the M81/82 duet. Both scopes gave excellent views. M81 spread out to its full dimension, M82 displayed its indescribable mottled profile. Bumping the magnification to 120x, I was very pleased with how much structure was possible through Argo. M81 showed a fine dark soutwestern frontier. Pinches and irregularities along the full length of M82 were perceptible direct and without real effort. Truly this pair is gorgeous at 6 inches of aperture - during optimal 5.5 ULM seeing.
It was here where something unexpected occured. Dan noted a fine 6 arc sec separated matched 8th magnitude double southwest of M81. The amazing thing was that the 4 inch did a cleaner job of resolving the pair. Both Dan and I remarked on this. What the heck is going on here? Why does the pair look slightly diffuse in Argo, and so well defined in Takky? Hmmmm... "Anomaly is the root of discovery." But the answer is yet to be explored.
M44 had visibly descended, I ran the 12.7 magnitude limiting telescopic magnitude check on both scopes. At 120x, Argo could just hold the star. At 114x Takky required slightly averted vision. For Argo, the calculated unaided transparency in that region of the sky was magnitude 5.5 and 7/10 stability. While that of the 102mm was magnitude 5.7 through 8/10. Aha! Either the Tak has better optics, OR sky stability is literally poorer through a 6 inch than 4 inch! Could this be our answer? Does a 4 inch scope actually enjoy better sky stability than a six inch? Have we explained our anomaly?
Sky and Telescope articles notwithstanding, that's where I put my money. Folks, I see this all the time. Take three scopes. Say 6, 8, and 10 inches in aperture. Make sure all are "diffraction limited". Follow Saturn's descent through the night sky. The six inch will show Cassini clearly for the longest period. The 8 inch will lose the hard edge of the discontinuity before the six. But by this point the 10 inch will struggle with defining the division meaningfully. A matter of optics? Sure - partly. But I checked Takky's correction last night - slightly overcorrected, perhaps 1/6th lambda. Argo is 1/6th wave undercorrected. The optics are a wash. For you may perceive, seeing is an "area" function. The larger the conduit of sky you look through, the more distortion (chaos) you include in the image. Meanwhile, resolution is linear. A doubling of aperture (which doubles resolution) means four times the energy of atmospherically-scattered photonage. All that chaotic light does bad things! Simple as that. Right Cor?
Well that's what I believe happened with the M81 pair. All evening long Takky get's 8/10 seeing and Argo get's 7/10.
Sure I could be wrong, but rather than argue theory simply setup those scopes and follow the Saturn action. Who's Cassini diffuses first???
Now, this is all getting very long-winded. So I need to bring things to a conclusion.
Dan and I went on to make a full tour of the numerous galaxies in Leo and "East of Denebola" - M105 to M60. Six inches was clearly superior to four amongst the Realm of Galaxies, BUT Takky gave very nice views all along the way. Even the toughest of them - M98 - was no match for the "Little Scope That Could".
During this tour two things of especially note occured: One: We unexpectedly came across a faint galaxy (probably 11.0 magnitude, 6x2arcmin, 13.5 ASB NGC3593) just west of the Leo Trio. And two, I could not locate that third galaxy which had triangulated with M59 and 60 two nights ago during deepsky through the 80mm Pup achromat from Backyard Boulder Creek.
This last concerns me. Everybody knows I want to become an astro celebrity! I've missed my big chance! Surely it must have been a comet. OK, you comet-seeks out there, find that thing! But unless you know your way among a milliard of faint galaxies, your chances are slim...
And oh yes, in the few remaining moments I have to dedicate to this report, shall I wax eloquent about the wonders of viewing the night sky through 750mm's of aperture? Of course! But alas, I have nothing to report. Not only did Dave have his Starfire packed away by the time Dan and I made our second trip to the observatory, but the FPOA had locked up the Big 'Un.
But at least I had a chance to view planetary NGC6212 in Hercules through a 7 inch Mak Newt.
Oh yes, You are Welcome, Blonde Lady.