Archive for February 2018

Edmund Scientific of Years Past

February 21, 2018

Edmund Scientific was the company that spawned my interest in amateur astronomy. From the following books (pictured below) to my first serious telescope, an Edmund 4.25-inch f/10, equatorially mounted reflector.  

It was the “Edmund Sky Guide” that taught me all about Sirius and the companion. However, it would be almost forty years later, before I would finally see the companion.  

“Time in Astronomy” taught me how to use setting circles, which really opened up the world of deep-sky observing for me.  At that time, I didn’t know of another kid or an adult with an interest in astronomy.  So…it was up to me, to learn how to become an amateur astronomer.  I did this by reading everything I could find, and taking my telescope out into my back yard, night after night.   

It was the mid to late 60’s thru the 70s which I call the golden years of amateur astronomy. The days when 6-inch reflectors ruled the day (or night) and fortunate indeed was the amateur that owned an Edmund Scientific or Criterion 6-inch f/8 EQ reflector.

The days when every amateur wanted to see all of the Messier objects.  As a young enthusiastic amateur, the thought of seeing all of these showpiece objects didn’t even seem possible.  

Being young, always feeling great, no responsibilities, dreaming of a better telescope, or another Kellner eyepiece and a clear night.      

Now what more could any young amateur astronomer ask for?  

1910322_1_IMG_2476

 

 

 

Visual Observing with a 6-inch f/6 Imaging Reflector Telescope

February 10, 2018

 

353947125_1_1

The above photo of my “prized” 6-inch f/6 reflector telescope.  

This telescope was a gift to me:  (Winter 2018) 

When I first became interested in amateur astronomy, during the 60’s, the 6-inch reflector was “definitely” the most popular telescope for the backyard observer.    

I always wanted a 6-inch f/8 Edmund EQ reflector, but as a middle-schooler, this was not possible.  Any extra money, went toward Bass Weejin shoes, Alpaca sweaters, dress pants, and the essentials needed by a teenager during those years.  I spray-starched my shirts at night, and ironed them myself.  Kids dressed better in those days.  No jeans with holes, or shirts not being tucked in.  

So, it would be quite a few years later before I would purchase my very own 4.25-inch Edmund f/10 EQ reflector.  But, a couple years later in need of more aperture, I sold the 4.25-inch, to purchase a 6-inch Criterion f/8 reflector.  Then life got really busy and I sold the 6-inch.  

It would be almost ten years before I would come back to amateur astronomy.  However, the hiatus might have been a good thing, as I came back as a much more serious observer, with a new 10-inch EQ reflector.        

Preserving the past:    

One of my desires has always been to bring back the excitement of the glory days of amateur astronomy, when all kids wanted a telescope.  This is primarily one of the reasons for my blog, which you are now reading. 

The nights of the solitary observer in the backyard, attempting to locate and observe a few of the Messier objects with a 6-inch reflector.   

Testing my new 6-inch f/6 reflector: 

But how would this telescope perform on a couple of difficult tests?  One of the most difficult would have to be seeing Sirius B, the companion to Sirius.  

I made my attempt on February 8, 2018, with the 6-inch to see if the companion would be possible?  

A larger secondary mirror:

An imaging reflector has a larger secondary mirror, and this can have a negative effect as related to resolution of fine detail, and the separation of difficult double stars.  

When I took my first look at Sirius it was obvious that seeing was pretty good.  SoI started with a magnification of 150x, but to no avail and worked my way up to 232x.  

After more than an hour of patient and careful observing, I thought the companion showed itself on at least a couple of occasions.  However, fleeting and intermittent only, maybe just a wink, or was this just my imagination?  

As amateurs, we all know that our mind and eyes can play tricks on us, especially when we are wanting to see something really bad. 

I’m planning to try this again, if and when that perfect night with excellent seeing presents itself.  As always, I’ll determine where the companion should be located beforehand, in my eyepiece.  

If we know the position angle of a secondary star, it can most often help us see a very difficult companion. 

The Trapezium in the heart of the Orion Nebula:   

Starting with 232x, I was surprised how easy it was to see the E star, but the F star was not seen.   

February 8th 2018, an observation of the Trapezium stars: 

There were beautiful airy discs rings surrounding the “four” primary Trapezium stars, at the 232x magnification.   

Note:  An imaging reflector most often requires the use of an extender tube when observing visually to achieve proper focus.  

The optical tube assembly:  

6-inch OTA, f/6, with a 2-inch focuser, a 6 x 30 finder and it also included tube rings, designed for a narrow-Vixen style dovetail.  An excellent quality telescope in all aspects.  

 

The original dovetail was too short, but I found a unique way to utilize the “too short” original.  I ordered a 13-inch dovetail to replace the short one, which allows for better balance. 

The telescope optical tube is fairly heavy, and it was difficult to set up on the mount.  I needed a handle to more easily mount the telescope.  

So, I just flipped the original dovetail upside down, and it bolted perfectly on the top of the optical tube.  This became the perfect handle I was looking for. 

IMG_0247 

I added an 8 x 50 finder:   

This is the minimum size to effectively locate very faint deep-sky objects, when using a sky atlas. 

My primary reason for purchasing this scope was for portability, ease of carrying and set-up, and take-down time.     

 

Fortunate for me, I had a Vixen GP equatorial mount from a refractor purchase in mid-90’s.  I did have to purchase an additional counterweight to properly balance the reflector.   

There was a problem, but not with the telescope:  

My older Vixen GP tripod was designed for a refractor, and too tall for a reflector.  I have to be seated while making observations, in order to make notes and pencil sketches.  

I didn’t realize until later that Vixen offers a short tripod, designed for Newtonian reflectors, but just the shortened aluminum legs with a base sells for ~ $200 dollars.

A light bulb turned on in my head: 

About 15 or more years ago, I bought a set of Vixen (standard) tripod legs for $20 at a local astronomy event.  They appeared to have never been used, and I’d had them in storage ever since. 

Why not attempt to shorten my extra set of standard tripod legs to Vixen specifications?  

So, for most of the afternoon, I spent several hours, sawing, drilling, and filing.  The results were worth my time and effort, and all modifications looked really good, or what I would call….factory.  

And now, I can enjoy observing with my 6-inch while seated, using an adjustable astro-chair.  

IMG_0193  

Another mount which allows a seated position:

Another gift:  

A slightly used Celestron CGE Pro, which has a payload of 90 pounds.  I don’t use this mount with a tripod, due to its height, but I have a system to secure to my back deck.  

I use it primarily with my 10-inch reflector, but it also works well with the much lighter and smaller 6-inch.  Rock steady for sure!  

All is well call me when you got out of church.png

I’ve found it “almost ” impossible to look through an eyepiece, make notes and a sketch, in a standing position.   Roger Ivester

A great review as following of a TPO 6-inch Newtonian by James Dire:

Dire, J.R. 2016, The TPO 6-Inch Newtonian Telescope, Astronomy Technology Today, 10, 3, 67-70.