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My Newest Telescope 14.5 inch f/3.5 Grab & Go Telescope (custom)
 
Sam, Cory, Greg (me), Leo & Leo & Sam with 15x50 Binoculars at Mt. St. Helens September 9th, 2018
 


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First Light: March 17th, 2017  
This Telescope represents an effort to go smaller and lighter, but still provide enough light gathering power to provide Deep Sky enjoyment. 

This Telescope was built to replace the 20 inch f/3.55.  This is an Aluminum Telescope with a few plastic components. 

This new Telesscope is compact enough to travel fully assembled in a compact car.  The Optical Tube Assembly (OTA) weighs 55 pounds and can be lifted by one person off the Rocker/Base.  As odd as it might seem, being able to move the Telescope without a complete take down and re-setup is an imporatant feature.  At Star Parties, sudden storms or late arriving RV neighbors blocking your horizon views can be problem-matic if you are already setup.  Also, trees in a wooded site create the need for a quick relocation as I would track and follow objects.   Not to mention, I can only wonder how many times, I did not go out due to setup hassels.  All, hopefully gone now.  Transporting Telescopes inflicts the most wear and tear on these instruments.  The small Scope travels well and is easy to protect in a vehicle.  Camping gear competing for space and/or falling on to the Telescope, is a lessor issue.  

Influencing the smaller scope choice was the memory of the 2006 Oregon Star Party (OSP).  The 10 inch Travel Scope was brought to show at the Telescope "Walk-a-bout".  There was no observing plan, but later that night, it was improvedly used to tour the sky wih ease.  It was easily moved from under a protective awning to the observing area and back again.   Another factor of influence to go smaller was the enjoyment Mel Bartels had with his smaller Scopes and their wide fields.  His 13.1 inch started as a desgin study for a larger scope.  Instead, it inspired him to make two still smaller Telescopes, a 10 and 6 inch super fast Telescopes. 


The larger field of view is a trade-off gain.  The 21mm Ethos, with a Paracorr (P2) provides a 1.42 degree field of view at 71x.  Locating objects is easier.  The 4.7mm Ethos with P2 provides 315x.  M13, is the benchmark object for determining performance.  Observing it at 315x provided an unexpectidly stunning view.  Another "benchmark" Object is NGC 4565.  The dark cloud is easily seen.  I routinely use a 7mm XW Pentax at 212x to observe it.  The key is to fine tune the Telescope's performance with the right eyepiece selection.   I rarely went over 300x with the 20 and 24 inch Telescopes.  I found that sky conditions rarely permited it.  Touring the sky at the 2017 Golden State Star Party (GSSP) demonstrated that this Telescope exceded my expectations. 

Fabrication by: Strassburg Machining
of Hillsboro, Oregon  
phone:  971-219-2995
 
Design Features:
The Cage-much of the design features are here.

Flexible mounting of Cage for Left or Right Eye use,

3 ring Cage sandwiches focuser between rings for high eyepiece payload capability,

2 Finder Mounting Shoe option to allow for a possible Laser Pointer-important for a low height Telescope.  Also user choice to mount the Finder for the left or right eye,

The Spacers between the Cage Rings have a large surface area to prevent racking.  They are bolted to the Rings and the Truss Brackets.  

The Spacers are slotted to allow Finderscope Shoes to be mounted to them and to reduce weight.  The Spider is also mounted in the slots.  The slots allow the Spider to be adjusted for alignment.

Holes in the Cage Rings reduce weight and wind resistance.

Inside dimensions of the Cage Rings are only 1/4 inch larger in radius then the Mirror radius to improve contrast and reduce excess material.

Mirror Box
"North End" accepts screw in feet to allow it to stand up-right (like a suite case) durring transport including possible flying. 

Ridges on the inside box allows covers to me flush mounted over the box for further protection for storage or travel.
 
Contrast added by 3 "tight" diameter Cage Rings and Primary Mirror Light Baffle,

Adjustble Tension Roller Bearings for Altitude Bearing.  Counter-weights are not necessary,

The Alt-Bearings are tall to provide a lot of surface contact to the Mirror Box to prevent racking.

1.75 inch tall feet for height and rocky terrain ground clearance,

Grab Rail for easy pickup and Transport, 

17.75 inch maximum outside diameter of Cage allows the Telescope to pass through an RV door.

Sized to fit in a small vehicle assembled.

The "Moonlight" Focuser's large easy to see knobs are ideal for guest observers.

 

 
 
Why the 14.5 inch Size?
Several sizes were considered, but non larger than the 14.5 inch.  I seriously considered a 10 inch.  At f/3.5 it would give a 2.1 degree field of view with a 21mm Ethos Eyepiece and Paracorr.  Ultimately I chose the 14.5 inch as a comprimise between Aperture and Field of View.  Further, the 14.5 inch Mirror Cell was the largest non-custom Mirror Cell produced by Aurora Precision.   In designing a Telescope, I try to minimize the number of custom parts.   Aurora (Nathan Currier) makes an excellent product.  This Telescope was also an opportunity to show case his components. 

This Telescope was built by "Joe Strassburg Machine".  Primary Mirror by Steve Swayzee and many components by Aurora Machine. Astro Systems provided the Spider and Secondary.  The Focuser is a "Moonlight" brand.


Why f/3.5?
While the development of the Coma Corrector is making the "Short Focus" Telescope a popular choice, there are draw backs.  Difficult to focus and large Secondary Mirrors are to name a couple.  I choose the f/3.5 as a comprimise.  With a Paracor-2 (P2), the Telescopes yields f/4.  A 20mm Eyepiece provides a 5mm Exit Pupil.  I think it is an optimin size for achieving light and contrast.  The 21mm Ethos provides a 5.2mm Exit Pupil.  The shorter Focal Lengths were intended to place the Eyepiece more within reach of the Observers Eyes without the aid of a ladder.  It isn't as necessary for a 14.5 inch, but it aids in the portablility department.  The assembled Telescope Tube can fit into a small car. 
   
 


Altitude Bearing Styling
The large Red Altitude Bearing is a dominating physical signature feature of the Telescope.  This was somewhat intentional to create styling.  It is even about 3 inches longer than necessary to do the job.  Typically I would not allow this because of the added weight, but it gives the Telescope an elegant look.  Circles and circular holes give the Telescopes its design theme. 

   
              
Left-Telescope Stored under Desk.  Right-Stored in a small Motor Home.  It fits through the RV door fully assembled (not recommended).     Ralf Nye's monster 14.25 inch f/7 Telescope featured in a 1970's Sky & Telescope article.  The scope towers over it's builder.  The 14.5 f/3.5 requires a chair, not a ladder, to observe through it comfortably.  The new scope highlights the dramatic evolution of Telescope designs.
 
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Grab & Go 8.2 inch f/3.9
The Explorer Scientific 8.2 inch Telescope
is a Telescope I have been considering for years.   Its price, carbon tube and light weight made it the choice of many available in this size.  With a 31mm Nagler Eyepiece and a Paracorr-2 (P2) the Telescope will yeilds a very large 6.9mm Exit Pupil and a very large 2.73 degree feild of view. 

The Telescope was modified to make it unique and more functional. 

1.] Tube was shortened by 2 inches to make it 28 inches.  This combined with it's 9.5 inch Tube make it a potential carry on Traveler.  This might be wishful thinking. 

2.] The Focuser was replaced with a "Moonlite" red Focuser for commonality with the 14.5 inch Telescope and to, perhaps, give it a "trademark" look.  The Focuser also reduce the weight slightly and the Focuser's height is 1 inch shorter then the previous one, giving it a lower profile for Travel.  It ijust seems to a better Focuser anyway.  The lower profile Focuser makes an extension tube necessary for visual use. 

3.] The heavy handle on top was replaced with a lighter rubber one.  The previous handle was designed to mount a Camera on it. 

4.] Finally, the Finderscope Mounting Bracket was changed to accept the same bracket that is on my other Telescopes.

My first Telescope was behemoth 135 pounds, 8 inch f/7.2.  This Optical Tube Assembly (OTA) may be less than 20 pounds on a 15 pound Tripod.  How easy it would have been to take this scope to the early Star Parties when I was 16 years old.  The 8 inch was my first serious Telescope.  I have gone full circle, in a sense. 

ES 8 with "Moon-Lite" Focuser retro-fitted.

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 Takahashi 60mm f/5.9 APO Refractor Telescope
  This Telescope was purchased to be the NEXT Imager.  It was used to image the 2017 Total Solar Eclipse.  It's weight is a mere two pounds.  It's weight makes it excellent for use on the Teagul Equatorial Mount.  It is also excellent as a traveler for future Total Solar Eclipses.  It has a standard Focal Length of 355mm.  A Focal Reducer gives this Telescope a 234mm Focal Length.  A Field Flattener increases the Focal Length to 374mm. 

A modification of the Focuser was made to make it a 2 speed. 

Image of the Telescope shows a 1600x1200 pixel Imaging Source/Celestron Skyris "Planetary Camera."  This Telescope can be used for observing.  A 24mm Televue Panoptic provides 14x with a 4.9 degree field of view. 

  The Takahashi Teegul Mount
This Mount has been modified to reduce it's foot print in a carrying case.  The Counterweight shaft has been removed and the counterweights have been placed on the mount's housing.
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 Televue 76mm f/6.3 APO Refractor Telescope
  Ordered:  September 2001
This was number 31 off the assembly line.  This scope was orderd at the 2001 Mt. Bachelor Star Party.  The 76mm gets the most variety of assignments.  It was fitted with a Coronado H-Alpha Solar Filter.  The 8-24mm Zoom Eyepiece gives 20x-60x for Solar Viewing.  The APO design makes the 76 excellent for Planetary and "Rich Field" viewing.   The  76mm is the size of the old 70mm Pronto and fits in an "under the seat" airline carry on case.  It went to the Venus Transit in 2004 and the Solar Eclipse in 2009 to image these events.  It also Imaged the 2012 Annular Eclipse and the 2012 Venus Transit.
  The Takahashi Teegul Mount
This is the only Tracking Mount that I own. I acquired it in 2003.  It is accurate, compact and an excellent traveler.  It uses custom made solid Aluminum "Latitude" 
Wedges" machined to 30 & 45 degrees.  They are interchangeable depending on the Telescopes travel destination.  They can be stacked to give Latitudes from 15 degrees up to 75.  Latitude Fine tuning is achieved by adjusting the Tripod legs.  The "C" Cell Battery pack was replaced by a lighter "AAA" battery pack.  For the 2009 eclipse, the counterweight shaft and Latitude wedges were left off to make the Mount a lighter "Alt-az" since ship board observing did not require an Equatorial Mount.  
 
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 Canon 10x42  Image Stabilizing (IS) Binoculars
  Acquired March 2014.  Normally, I wouldn't list Binoculars as a Telescope, but these are often used for their "grab and go" qualities.  No tripod or setup is required to observe.  The image stabilizing features eliminates the jiggling motion and gives a "floating effect."

These Binoculars have been fitted with filter adapters, that allow me to attach a UHC filter for observing objects like the North American Nebula and Veil Nebula.  I only put the filter on one lens and let the high contrast, view balance with the natural view
  These Binoculars provide a 6.5 degree field of view making objects easier to located.  It has a decent 4.2mm Exit Pupil and its compact size and relatively light weight, makes it easier to hold.  The 15x50 Canon IS were an attractive consideration for their power, but the 10x42s size weight, exit pupil and field of view won out.  

See My Book:  
Stargazing for EVERYONE with Binoculars
 
 
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  My Past Reflector Telescopes
20 inch f/3.55 Dobsonian (custom) First Light: January 7th, 2011  
.20 inch f/3.55 Telescope at the September 2011 Oregon Star Party
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This Telescope was designed by (me) Greg Babcock and Nate Currier of Aurora Precision and built by Aurora Precision.  It was built mostly out of Aluminum.  Many components were "off the shelve" products including the Truss Clamps,  The Astro-Systems Spider features a heated Secondary Holder.  The Mirror is 1-5/8 inch thick Pyrex made by Swayze Optical. 
 
The goal with the new scope was to increase ease of use and mobility.  It was patterned after the 12 inch Traveler.  A lot of the anxiety comes from transporting the scope.  The 12s hard Baltic Birch Mirror Box protects the scope during transport.  The 20s aluminum Mirror Box Case does the same.  The 20's heaviest piece is the Mirror Box, 65 pounds, its physically small (22.25 inches square), adding to the ease of handling.

To assemble, the Mirror Box can be lowered between the lock-able Alt-Bearings onto a guide track.  The height of the 20 permits attaching the Cage, and viewing, without a ladder.  And no ladder is required for observing.  The Mirror Box easily goes through a narrow RV door and travels well in the small vehicles.
The Cage design features 2 thin "Alucobond"  rings, with Aluminum spacers.  Tension from the Spider gives the Cage torsion strength.  This strong Cage is attached directly to the Trusses.   A del-ran Bridge between a Truss and Focuser Board, supports and stabilizes the Focuser Board.   It replaces what would have been an additional Cage ring.  A 20.25 inch Light Baffle just in front of the Primary Mirror and Cage rings only 21 inches in diameter, add contrast to the view.   The physical Size of the Scope is closer to that of an 18 inch.  The Telescope weighs 114 pounds. 

The Images don't do this Telescope justice.  The architecture could be described as an industrial look.  The red accent enhances the appearance.  

Top Image note: 
At September 1st., 2011 Oregon Star Party (OSP).  From Left to Right,  My 20 inch f/3.55,  Howard Banich 28 inch f/4 with black shroud, Mel Bartels 13 inch f/3 on aluminum stand.  Dave Danskey's 16 inch on Equatorial Platform (right).
Above image Is the first "operational" use; August 26th, 2012 in Central Oregon.  First Light January 7th, 2011 5:40pm-Cresent Moon.  
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12 inch f/4.9 Traveler (custom built-homemade) First Light-March 30th, 2008, 9:00pm - Orion Nebula  
   
        The Carry on Box-Brown 10 inch next to the black 12 inch.  Size volumes are nearly identical.
 
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  2008 Oregon Star Party Walk-A-Bput. 
In August of 2006, while sitting in the Atlanta Airport, waiting for the connecting flight to Portland, I began to sketch the new Traveling Telescope design.   We had just completed our Argentina trip.  Lessons learned from traveling with the 10 inch would be used in the new design.    The new 12 inch Telescope had the same origin as the 10 inch. A "Classic style" (full metal tube) 12 inch was purchased and many components were retained.  Improvements over the 10 inch were the detaching Rolling Cart and collapsing trusses for easier stowage.  The lid acts as a ground board in a pinch.   
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10 inch f/4.9 Traveler (custom built homemade) First Light: 2006      Sold in 2007  
     

I was inspired in part by Steve Swayze who took an 8 inch to the 1998 Caribbean Eclipse and by Mel Bartels 6 inch that went to Africa for the 2001 Eclipse.  Both Telescopes were light and clever.  A traveling "Dob" has been in consideration for many years.

The project started by purchasing a Classical Dobsonian and stripping for it's useable parts
Dave Danskey (right) and Nate Currier of "Aurora Precision" were employed to manufacture the wooden components & supply, Trusses,  fasteners & plenty of consulting.  Their work is responsible for the Telescopes turning out as good as they did. 

The Telescope went to Argentina in 2006 to view the Southern Sky.  It was sold at the 2010 OSP and replaced by the larger 12 inch model.

Image (Right):
In Argentina

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24 inch f/4 Ultra Light Dobsonian
My Signature design
(custom built-homemade)
First Light June 15th, 2000, 8:25pm - Sold in March of 2009
 
The Philosophy was to simply make a large Aperture Telescope as light and minimalist as possible so that one person can handle it and that it would fit it into a small vehicle with room for camping provisions.  The total weight was 105 pounds, with the heaviest piece 72 pounds, that being the Cell/Mirror combination.  The Pyramid Spider was to get the Secondary high enough so the focuser is above the Cage Ring, with the bottom of the Cage was flat for nesting. The Philosophy was to simply make a large Aperture Telescope as light and minimalist as possible so that one person can handle it and fit it into a small vehicle with room for camping provisions.  The total weight was 105 pounds, with the heaviest piece 72 pounds, that being the Cell/Mirror combination.  The Pyramid Spider was to get the Secondary high enough so the focuser is above the Cage Ring, with the bottom of the Cage was flat for nesting.  

The material used was Baltic Birch with an epoxy coating.  The outside of the Cage Ring was lined with an aluminum ring on the outside and a partial ring on the inside to give the Focuser additional support.  The Cell is an Astro Systems Baltic Birch with numerous holes and aluminum angle under and an Aluminum Strap wrapped around the rear outside to the Cell.  The trusses are made from foam filled 3/4 inch Graphite tubing and the Spider is made from Aluminum and Composite plates.  The tubing and plates were supplied by  Aerospace Composite Products

A flex board with Cam Follower Bearings is the Rocker that sits on a heavy Ground Base.  The Base is "hubb-less" to permit clearance as the Telescope rotates to the horizon.  The Primary Mirror was supplied by Swayze Optical. 

Imitation is the greatest form of flattery...
When I discussed this Telescope at the 2000 OSP walk about, I suggested that no one should try to take on this design because it is a lot of Telescope carried by few, yet reinforced components.  I thought the radical nature of the design would preclude almost everyone from wanting to build it.  Further, I expected mostly critism on blogs for its open design that seemingly leaves the optics unprotected.  Yet many Amateurs have built similar models.  Seven years after my Telescope's First Light, Obsession introduced an 18 inch production version with other sizes that followed.  Other makers have also introduced their own version.  
It has, unintentionally, become my "signature design." 

 
                 
         
                 
                 
   
Amateur Astronomy Magazine - Issue No.: 28 (Winter 2000)        
The Ultra-Light  / Minimalist / Large Bearing Concepts are NOT new.
   
  1979   1980 1980  1997 1998 2000 1970 Cave Optical 16 inch  
  Canadian Micheal Taylor's 15 inch featured in
June 1979 Sky & Telescope Magazine 
 
My
 12 inch
Concept 
Scott Beard's
17.5 inch
Large Bearing
Dobsonian 
My
18 inch
Ultra
Light
My
24 inch
Ultra
Light
The dwarfed 24 inch
gathers twice the light.
Pictured: Larry Hardin of
Hardin Optical
in Bandon, OR 
 
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18 inch f/4.55 Ultra Light Dobsonian
(custom built-homemade)
First Light: Saturday, June 6th, 1998, 8:38pm.  Traded in 2000 


This Telescope was my first Dobsonian.  It is a combination of Mel Bartel's 20 inch and Scott Beard's  rebuilt 17.5 inch Coulter.  This Telescope made the large bearing design popular.  It fits snuggly in almost any size vehicle and still leaves room for camping provision.  It weighs just 85 pounds.  The primary appeal of the design was the simplicity of the Mirror box being the Altitude bearings instead of a box.  It is made of Baltic Birch with a marine coating.  Trusses are Aluminum.  It has a conventional Cage, built by Chuck Detloff.  The Mirror is a 2 inch Thick Pyrex made by Swayze Optical.

The idea originated from NEED the need to transport a large telescope in a small vehicle to a favorite observing site while still having room for a passenger and gear.  Canadian Michael Taylor's 15 inch Telescope (see image below) fits in a small car.  His Telescope inspired me to study minimalist designs starting in 1979.  




Most innovative design Award July 1998
Table Mountain WA Star Party. 
         
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10 inch f/5 Torque Tube (custom built-homemade)    Built 1977 -Sold 1979 

  After the Telescope was sold in 1979  to Lynn Carroll,  Mel Bartels  improved the Mount by construct-ing and installing "Sector Drives".   I was fascinated by an article is Sky & Telescope that discussed different Equatorial Mountings.  It spoke highly of the "Torque Tube" design.   A design used by Boller & Chivens for their research Telescopes.  The "Tube" rotates around the outside of the Right Ascension (RA) Axis and places the counter weight to the rear of the Mount, removing encumbrances t the observer.  The Telescope can rotated 360 degrees around the Axis.  The mounting was built out of iron plumbing pipe.  The Telescope weighed 140 pounds.  40 pounds of that was the counter weight.

Images below:
Left:  Cut-a-way sketch of the Torque Tube Mount. 
The Torque Tube Mount, encouraged me to explore other "extended arm" Mounts.  The center image are of mock-ups of 14.25 inch Telescopes using "Single Arm" Fork Mount designs.  The Telescopes were never built, but several mounts were built.  Right Image: This mount was originally sold to the "Eugene School Distric" (ESD) in 1978 and later re-sold to Tom Conlin for his 16 inch Telescope.  It showed up at the 2008 Oregon Star Party (OSP). 
         
   
At the 2008 Oregon Star Party 

 
Cut-a-way sketch   14.25 inch Mockups using "Single Arm" Fork Mounts   
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4.25 inch f/4 Coulter Kit Newtonian Telescopes 1977 
  In the late 70s Coulter Optical came out with a Telescope kit for $49.95 that included a completed Primary Mirror and Secondary Mirror.  The rest was fairly crude, but the Optics alone were worth the price.  I buit several.  They were an excellent "grab & go" Telescope.
     
8 inch f/7.1 Newtonian Telescope (custom built-homemade)      Built 1977 -Sold 1979 
Picture above was taken in 1972.  The "flash cube" was a misguided attempt to improve my night vision.  I was 15 years old and the Telescope outweighed me by 30 pounds. Click image for larger image & article

Newspaper coverage of 1975 Public Star Party at Alton Baker Park in Eugene, Oregon.
The now classic Dynascope 6 by Criterion with it's $199.95 price tag, made it one of the most popular Telescopes in the early 70's.  It was the Telescope I sought to purchase before I took on building of the 8 inch. This was my first "Home Built" Telescope completed in 1972.  The decision to build it came when a friend talked me into purchasing his an 8 inch Edmund Scientific Mirror Blank and Mirror Cell for $25.00.  Until then, I was saving for a 6 inch Dynascope.   I was attracted to the 80% light gain of an 8 inch over a 6.   For $70 Cave Optical completed the mirror.  I joined the Eugene Astronomical Society (EAS) to acquire help and confidence to complete the project.  Charles Coffey graciously donated his time on the project.  
The mounting was made of iron plumbing pipe.  A 3 inch “sanitary Y” was used to achieve the latitude angle.  The Telescope weighed 135 lbs.  If I could go back in time and re-do this scope, I would remove that guide scope, pushing the balance forward, and cut the pedestal height in half and shorten the Declination Axis.
Built in 1971 -  sold in 1976      
                 
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     My Past Refractor Telescopes
       
Jason 60   Brandon 94    Brandon 130   Televue 70 Pronto   Televue 85 (TV 85)
                 
94mm Brandon f/6.8 APO Refractors    
     

Refractors have always filled a nitch the big Dobsonians can't fill.  They are  portable good for "grab and go" purposes and they are good for imaging. 

My interest in Astronomy can be traced to the time I looked at the Moon for the first time through a neighbors Tasco 60mm variable power (15x - 60x) Telescope,  I was age 7 and awe struck.  This was 1964.  I decided then that I wanted a Telescope.  In 1968, at age 12, I purchased my first Telescope, a Sears Discovery 60mm which was not Equatorially mounted.  I felt a 234x  telescope was adequate enough to get me started.  Yes I was sucked into the assumption that capability was best measured by magnification.  One evening, I became impatient with the mounting when I observed Venus slowly dropping out of the field of view.  I assumed that the mount was sagging, but the reality was that the Earth's rotation that was causing the movement. 
 
My second 60mm was a JC Pennies 60mm with an Equatorial Mount.  This new Telescope was beautiful.  It was blue in color and at 1000mm Focal Length, it was long and slender.  I how to use an  Equatorial Mount.  In 1973 I sold this telescope to fund the building of the 8 inch Telescope. 

In 1984,
In preparation for the return of Halley's Comet, I purchased a "Jason" 60mm Refractor (pictured) to have a tracking Equatorial Mount, but Halley's Comet was a bust and I eventually, I sold the The Jason in 1988.
 

I have owned two 94mm Brandon Telescopes.  I purchased the first in 1988.  It was responsible for bringing me back into Astronomy.  With a 40mm Konig Eyepiece, I had a 4.4 degree field of view and enjoy scanning the sky and finding objects effortlessly.   Aperture feever soon took hold and I sold it in 1990 to fund the 130mm Brandon purchase.  The next 94mm Brandon was purchased in 1998 to replace the 70mm Pronto as my Eclipse Imaging Scope.  It was used to image the 1999 Eclipse.  The optics in the Brandons were made by Christian, currently of Astro Physics.  It was sold it in favor of using the much smaller and lighter TeleVue 76mm

The Televue 85 (TV 85) was purchased almost impulsively, August 2001 at the Oregon Star Party.  It was an attempt to downsize from the 94mm Brandon.  One month later, at the Mt Bacheor Star Party, I learned the Televue 76 (TV 76) was coming out.  I ordered because it would fit in a carry on box much better than the TV85.  I kept the 85 for several years mostly as a Rich Field Telescope (RFT).  With a 40mm Pentax Eyepiece, it yielded 15x and 4.7 degree True Field.  It was also excellent as a Planetary Telescope.  I have observed Saturn at over 200x with excellent results.  The TV85 was sold in August of 2011 in favor of making the TV76 the "everything" Telescope.

             
             
             
130mm Brandon f/8 APO Refractor
 
     
     
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     for Beginners
For beginners I recommend a Dobsonian with 3 to 4 good eyepieces (Plossls or better), including a good low power eyepiece.  What a lot of beginners soon learn is, the low power eyepiece is the most used.  

The Dobsonian is suitable for beginners and experienced observers.  Why Dobsonians and why this one?  It offers great value for the cost.  It assembles quickly.  The eyepiece is near the top of the Telescope, making it comfortable to look through.  An 8 inch is a serious aperture with almost twice the light gathering power of a 6 inch without adding a lot of weight.  It travels well in small vehicles. 

I do not recommend "goto" mounts for beginners.  I like the concept, but they are often troublesome to operate.   In reality, we still need to know the sky and what is worth looking at on a given night.  That comes from websites, books, charts and experience.


Dobsonians do not track, but you will find them easy to operate.  Equatorial Mounts with their tarcking is nice to have, but can be expensive, and awkawrd to transport and setup.   This is the quickest way for your scope to end up in permanent storage.

Equatorial Mounts are excellent for imaging, but I have seen the interest in imaging faulter as quickly as it comes.  I recommend giving the casual observing a try first.  observing.   For imaging, I use a small refractor, it requires only small mount.
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  Telescope Links
         Sub f/4 Telesscope Links
       
Mel Bartels
fleet of f/3s
  Lockwood
14.25 f/2.6
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8 inch f/3.8
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12 inch f/2.8
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10 inch f/3
                 
 
Short f/ratio Telescopes-Seconday Mirrors are large
What is the MINIMUM size that your Secondary Mirror's minimum Axis should be?

Minimum Secondary Size Equals (d) divided by the ( f/ratio) of your Telescope..
d = the center of the Spider to the Focal Plain when the Telescope is focused at Infinity
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My 20 inch Telescope:  d = 13.75 inches.  The f/Ratio = 3.55. 
|Minimum Secondary Size = 3.87 inches
The 20 inches Secondary's actual aperture, 4.25 inches.
source: Gary Seronik.com
 
Short f/ratio Telescopes-Seconday Mirrors are relatively closer to the Primary Mirror.
To catch the "wider" Light Cone, what is the OFFSET of the Secondary Mirror?
The Choosen Secondary Mirror size is divided by the f/ratio x the constant 4.
 the center of the Spider to the Focal Plain when the Telescope is focused at Infinity
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My 14.5 inch Telescope:  Scondary = 3.5 inches dvided by ( the f/ratio = 3.5 x constant 4)M
The Offset = .25 inches.
   
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Contact Me     Greg Babcock  at:  gbabcock145@gmail.com