My Continued Adventures with an Istar 5″ f/12 Refractor

My 'pet': a wonderful 5" f/12 refractor.

My ‘pet’: a wonderful 5″ f/12 refractor.

A continuation of a review I performed here.

Wednesday June 5, 2013:

I awoke this morning more resolute than ever before that I would do something about my childish predilection for hoarding telescopes. I’m not a collector; I’m an observer. What need have I for multiple telescopes beyond the vainglory of possessing them?

People always flourish in the shadow of others. The young, impoverished Barnard used whatever instruments he could get his hands on before acquiring his beloved ‘pet’, a fine Byrne refractor of 5 inch aperture. His first serious telescope was a three inch refractor, which he found to be mediocre in quality. Barnard became heavily indebted when he acquired the Byrne. At first, I couldn’t understand why the young man would do such a thing. But then I realised that he was lucky enough to have discovered his calling in life. He did not have a family to provide for either, save for his mother, who kept in poor health for much of her life. Barnard was frugal to the core and managed to pay off the debt without seriously changing the quality of his life.

I thought some more about Barnard’s choice of optician. Certainly, the young man from Nashville Tennessee was not overly concerned with his choice of instrument maker. He did not seek out the firm that had the greatest reputation in his life and times, that of Alvan Clark & Sons, but was happy to trust the judgement of others who had recommended John Byrne of New York, as a viable alternative. The immediate availability of the instrument was also another contributing factor to the young man’s purchase.

Apparently, Byrne had established himself as a maker of high quality refracting telescopes after serving his time as an apprentice to noted telescope maker, Henry Fitz until 1863. After setting up a small optical shop in New York, Byrne managed to sell a fair number of smaller instruments to customers across the continental United States. His 4- and 5-inch instruments proved quite popular with his most discerning customers, and ranked among them was George Ellery Hale, who acquired a 4-inch Bryne achromat as his second telescope. At first, Byrne offered his 5-inch instruments at a f/15 relative aperture, later introducing shorter focus instruments with relative apertures of 9 and 10.5.  By all accounts, Barnard’s instrument was of the f/15 variety.

An example of a 5" Byrne refractor, similar to the instrument E.E. Barnard used to propel him to world wide fame. Image source:

An example of a 5″ Byrne refractor, similar to the instrument E.E. Barnard used to propel him to world wide fame. Image source:http://astro.union.rpi.edu/telescope.html

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

When a telescope of the calibre of Tiberius comes along, what possible need have I for all the other instruments I so greedily hoard? Ole Edward Barnard would surely disapprove of my avarice. “You dunderheid!” I can almost hear him boom. Why do I possess not one, but two 3.1” refractors? What need have I for the finest 4-inch classical achromat money can buy? And what of my Synta 6” f/8?

Who am I trying to fool?

All I really require are two telescopes (not three!), a small portable instrument for travel and/or quick excursions outside, as well as my choice 5-inch Istar f/12, which will become my one and only workhorse. Any funds raised from the cull will go to my wife and kids.

And so, with all the ruthlessness of Marcus Licinius Crassus, I made preparations to decimate my greedy herd.

One man, one life, one telescope.

Solidarity: 0ne man, one life, one telescope;

…….and a 3 inch companion.

Thursday, June 6, 2013

23: 30h.

Temperture 10C  and a glorius 1025mB rising slowly.

The clement weather by day was followed by a calm and clear sky after sunset. ‘Tis the season of noctilucent clouds.

The Remainder.

The Remainder.

My brother-in-law, Robert, came to visit us for a short vacation. He has, for many years, expressed a keen interest in my star gazing activities and accompanied me to the garden after the boys hit the hay, where my large telescope, Tiberius, and its li’l’ companion, Bessy, were both set up for a brief vigil. Conditions were made quite unpleasant by the swarming midge fies that come to life in weather like this.

Still, I managed to train both telescopes on Izar in twilight; I’m quite good at that kind of thing!. I was keen to show him the difference between the views of the same object through both telescopes- a useful instruction in the noble art of observation. For convenience, I used the same eyepiece, a 6mm orthoscopic, delivering 200x in the smaller instrument, Bessy, and 254x in mighty Tiberius.

Well, what a lesson that turned out to be! Both telescopes resolved this orange and emerald  pair. Bessy appeared to catch the secondary associated with the first diffraction ring and, as such, was slightly smeared out as the seeing varied from moment to moment (Note to self: is the separation really as great as 2.8″?). However, the view in Tiberius, in comparison, was simply magesterial! The companion was beautifully detached from the diffraction gunk of the primary. But what did Robert think?

“It was definitely harder to see the companion in the smaller ‘scope but the definition in the larger one was just perfect!”

That’s the power of a larger object glass!

The differences between the views in both instruments were less dramatic for the famous Lyra Double Double (Epsilon 1 & 2 Lyrae), perhaps because both instruments could clearly resolve the quadruple system. But I could tell the larger ‘scope captivated Robert far more.

When we had enough of the biting insects, we ventured indoors. But there will be more opportunities in the next few days. The forecast bodes well for a swell weekend.

Friday; Scorchio!, Saturday: Scorchio!, Sunday: Scorchio!

I leave you this evening with the allegory of an obscure (to many) Scots astronomer, the weegie, Henry McEwen, as recounted by Dr. Richard McKim, who adopted a fine 5-inch Wray refractor as his poison. And just look how much he achieved what that dear old telescope!

See here

and here

Saturday, June 8, 2013

For the last two nights, my brother-in-law and I waited for the sky to fall as dark as possible. But despite enjoying balmy, largely cloud free skies by day, the late evening has, this night and last, brought in a slow moving bank of cloud, making observing well nigh impossible.

It’s very disappointing to say the least.

All dressed up and nowhere to go!

But there will be other nights.

Tuesday, June 11, 2013

Time 01:30h

1014mB rising slowly. Temperature 12C

Was not expecting any clear skies this evening and none were granted until well after midnight, when a few holes appeared. I trained Tiberius on a couple of warm up systems first. Beginning with Delta Cygni; beautifully split at 256x. The more difficult Pi Aquilae was nicely resolved at the same magnification, despite its signifcantly lower altitude.

Then I spent 30 minutes examining Lambda Cygni. Decided to go for 381x (4mm ortho). Very encouraged once again. In the best moments, both stars appeared as if they were touching each other north-to-south. I’d estimate the seeing as 1.0-1.1″ tonight during the best moments, without filters.

Lambda Cygni companion; proxime!

A rapidly brightening sky and some high altitude cirrus conspired to bring the vigil to an end.

Wednesday, June 12. 2013

 Time; 23.20h

 1002mB, rising, temperature 12C

Fielded my large telescope, just as soon as the sky cleared this evening. By 22:45 I had managed to track down Epsilon Lyrae. Tiberius made light work of this system in a fairly bright sky. The images are incredibly stable in this instrument. Hardly a quiver at 308x. Indeed it got me wondering whether, if I were skilled enough, I could resolve this earlier, in a brighter sky. I bet a nice polarising filter might be a help here.  I could experiment with magnification and the like. With go-to drives, it would be easier to find these brighter pairs. With altazimuth, non-motorised, ‘push to’, it’s a considerably more difficult nut to crack – but its doable.

By 23:00 a salmon pink crescent Moon hung serenely not far above the western horizon. I trained Tiberius towards her with some anticipation, thought about which eyepiece I’d go for first, and then made my decision; a 18mm orthoscopic. I chose well, for it beautifully framed the waxing crescent in the field of view, the cusps almost touching the field stop. Again, despite its low altitude, the image was impressively stolid, despite its less than perfect definition owing to dust and low altitude. Obviously a very calm evening here in the glen.

Some astronomers consider the Moon as a form of light pollution. I understand what they mean, but there are some nights when you just have to pay it some telescopic homage. After all, we wouldn’t be here without its stabilising influence.

Awaiting maximum darkness.

Thursday, June 13, 2013

Pat your self on the back young Tiberius!

 A job well done!

Delta Cyg looked great,

 so over I swung to Lambda,

at 308x, a star so stable

 I saw a tiny, bleeding pimple!

 

At five minutes to midnight, I saw the duplicity of Lambda Cyg more vividly than ever before. Congrats Tiberius!

Where next Columbus?

14:40h

Let me try to put last night’s observation in perspective. I have been trying to see this incredibly difficult binary star for about 18 months. I have trained a half dozen refractors at it including a 5” f/9 Meade ED, a 5” f/9 Russian achromat, a 6” f/8 super ED doublet, and a 6” f/8 achromat (Belisarius) in the hope that I would get a clean split. The view I got last night with Tiberius was, by some considerable margin, the best yet! For it leaves me in absolutely no doubt that this 5” f/12 refractor was the very best choice for me. This telescope can reach the limits of its resolving power under my skies. It is supremely adapted to the conditions that prevail here.

I am not entirely sure why the larger instruments did not do so well as Tiberius. Perhaps going from 5 inches to 6 inches crosses a threshold where a small increase in sensitivity to atmospheric turbulence negatives any advantages of a slightly larger aperture? A 4-inch is just too small, a 6 inch a bit too large, but a 5-inch seems just about perfect. My old Tal 125R achromatic came very close but was not as well corrected at blue wavelengths. I have no explanation for why the Meade 125ED never got this close on this particular system, apart from not having the right conditions? Perhaps the image of the star was too bright in the ED ‘scope?

It matters not in the end. Tiberius has little to prove.

I believe my eyesight is nothing to write home about. If ole eagle eyed Dawes were with me last night, he’d probably describe it as cleanly resolved. So too would Sheldon Wesley Burnham. I’m only grateful to have gotten this far with my large telescope.

No doubt, over the coming weeks and months, others will lay claim to this system. That’s always the way innit? They’ll be sightings in 6-inchers, 5 inchers. Heck, someone might even chime in with a positive split in a super duper 4-inch, LOL.

The Goldilocks 'scope!

The Goldilocks ‘scope!

Barnard and Swift often shared information about nebulae in their voluminous correspondence. In one of his first letters to Barnard, Swift had invited the budding astronomer  to search for the nebula surrounding Merope, one of the Pleiades. It had first been reported in 1859 by the German astronomer Wilhelm Tempel, from Venice – this ‘breath stain’ on the vault of the heavens would, Tempel later declared, perpetuate his name. Ever since, opinion had been sharply divided as to the nebula’s existence or non-existence, some seeing it readily, others being unable to get a glimpse of it. Among the doubters were G.W. Hough and S.W. Burnham, who despite being armed with the powerful 18.5 inch refractor at the Dearborn Observatory, could find no trace of it. Tempel, on the other hand, had claimed it with a 4-inch refractor, and Swift with only a 2-inch!

On commencing his own search from the yard of his house on Patterson Avenue, Barnard found the nebula ‘plainly visible’ in his 5-inch Byrne refractor.

From The Immortal Fire Within: The Life and Work of Edward Emerson Barnard (Sheehan, W, pp 82-83)

Monday June 17, 2013

01:35h

Temperature 11.7C, 1030mb, rising.

My large telescope continues to please like no other. Trained the instrument on Lambda Cygni using 6mm Delos ocular and light blue #82 yielding 254 diameters. Detected the companion quite plainly as a pimple on the primary; very distinctive. North-south orientation, beautiful to behold.

Friday, June 21, 2013

The Summer Solstice has arrived.

While browsing tinternet this evening, I discovered that my large telescope has grown more famous than me. That’s right, Tiberius has eclipsed the semi-known man, the bruiser of egos.

Analysing my every word, they attempt to deliver a verdict on my telescope, having never looked through it.

How ingenious!

I have left that place far behind now. Mission accomplished.

They have no need of my censorship, for there are, thank goodness, plenty of grounded observers out there who can spot the fantasists and charlatans of the telescope world.

I seek neither the favour of my contemporaries, nor their advice.  History has shown me the way forward. Have you not read the life of Barnard or Harry (Henry) McEwen? Have you not studied their beautiful planetary drawings, admired their dedication and patience at the eyepiece, their marriage to a single telescope?

The human eye is far more ingenious than your master optician will ever tell you!

I respect my ancestors and the equipment they used. These men are my heroes; for their testimonies are unimpeachable.

What’s for you won’t go by you!

I will speak no more here of my large telescope.

 

 

 

 

 

 

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