Degree / Setting Circles on a Dobsonian. Zhumell Z1. 0 with Digital inclinometer and Degree Cirlce.
One of the most troublesome issues a new astronomer faces with a manual telescope is that of finding things to look at! It’s fairly simple to line up the sights on the moon or Saturn, but what if you want to see the Ring Nebula (M5. Great Hercules Cluster (M1. If you don’t have a GOTO scope you’re pretty much stuck in the mud. While learning how to star hop is cool and the ultimate way to go, it takes time to learn.
So what’s an aspiring amateur astronomer with a cool Dobsonian to do? Make a manual PUSHTO system, that’s what!
Zhumell Z10,Degree Circles,Setting Circles,Inclinometer. Home; Current Conditions. Chicago Stargazing Weather; ISky Galleries. Backyard Astronomy; Star Parties. You are here : Illinois SkyWatch » Astronomy, How-To » Degree / Setting Circles on a Dobsonian. Degree / Setting Circles on a Dobsonian. Published Thursday, July 7, 2011 By croman. So what’s an aspiring amateur astronomer with a cool Dobsonian to do? Make a manual PUSHTO system, that’s what!
Twin Tube Telescope * Manual Dob Setting Circles * Binocular Chair. Manual Dobsonian. Setting Circles. Binocular Chair. The Kid Peek Telescope. Downward Looking. Binocular Mount. Easy Alt/Az Mount Modification. Barn Door Mount. Telescope Observing Stool. Model '22X4' Cheap and Simple. Home Built Astronomy Projects © 2014 Rod Nabholz. CURRENT MOON lunar phases. Intro: Manual Setting Circle for Dobsonian Telescope. As a long time viewer of instructables.com, I am happy to present my FIRST instructable. This shows how I made manual setting circle for my dobsonian telescope.
- The Dobsonian Telescope, A Practical Manual for Building Large Aperture Telescopes tells how you can build a state-of-the-art Dobsonian telescope using readily available materials and supplies. Every step of construction is detailed in. As a result of this three-year collaboration between authors David Kriege and Richard Berry. Installing precision digital setting circles; Setting up and taking down the telescope.
- DOWNLOAD and browse the TScope DSC manual: TDSCmanual.pdf (1.5Mb) Options and Accessories All prices plus shipping and handling; typically $10, more. Digital Setting Circles (DSCs). TScope DSCs work with any Dobsonian-style telescope that has optical encoders or any scope that is compatible with one of the many optical encoder mounting kits available.
A manual PUSHTO system utilizes an Alt/Az system of Degree circles, an inclinometer and a good star chart or computer planetarium application to provide coordinates of things you want to see. The Dobsonian base was created in order to provide amateur astronomers with low cost, big aperture solution for the average person. The majority of cost is associated to the optics of the system.
Everything else is up to you. What You Need: Degree Circle – *FREE*Cloudy Nights and Star. Trak are great starting point to begin. Star. Trak is actually an application you download and run that is pretty cool. Inclinometer – *$3.
Wixey is the choice of many PUSHTO owners. Its small size makes it ideal. I chose the Husky Digital Level from Home Depot.
The price is basically the same but I like the bigger orange size. Check ebay for used ones if possible. Using the cheapo non digital ones are really not recommended. Some sort of cutting tool – *???* I utilized a jigsaw for cutting a 2″ notch on my top base board.
The choice is up to you. Velcro –*$5- $7* The velcro is used to tape down your Degree Circle to the bottom dobsonian base board. It can also be readjusted easily because of the velcro.
Glue is usually a one shot deal. Print Out Circle and Laminate –*$7* I had my 2. Staples. While you can print this out yourself you simply can not beat the convenience and simplicity of Staples. The lamination alone is worth the cost as you will NEVER have to worry about it getting damp, smudged, torn, etc… Don’t be cheap… just do it. You’ll thank yourself later. Step 1. The first order of business is to figure out the size of your base so you can download and print out your Azimuth Degree Circle.
The azimuth degree circle will show you 0 – 3. There are many sizes of degree circles available. For this tutorial I will be utilizing a 2.
Once you have your base size, 2. It’s really that easy! You will most likely need to cut a small hole in the center of the circle in order for it to fit over the screw, threaded bolt that holds the 2 base boards together. As you can see below the Zhumell Z1.
All dobs are different but they basically all work the same way, the base boards spin in a circle. Zhumell Z1. 0 2. 2" base with setting circle.
Step 2. Notch out the top base board with your cutting tool of choice. Chose to cut a 2″ section out so I can make adjustments with my pointer if needed. More on that later…. Reassemble the dobsonian base and it should look similar to mine. Give it a spin and notice how the degrees are being presented to you.
This is your Azimuth indicator window. Degree Circle. Step 3. Attach your Digital Inclinometer to the OTA. Most commercial dobsonians like my Zhumell are metal. This makes attaching the digital level easy. If you dob is made of sonotube, wood, etc… you will need to devise a way to anchor it to the OTA.
Zhumell Z1. 0 with husky Digital Level. How I use this system in the Northern Hemisphere. Now that you have everything assembled let’s talk about how this thing supposed to work.
Everyone has their own way of doing this and it is basically trial and error for a night until you figure out what works for you. I will explain what I do to get DSO and other objects into my FOV.
Your mileage may vary. At this point in time make certain that your base is LEVEL! If your base is not level your altitude will be off and that is not what you want. It only take a couple minutes and those minutes save you hours of frustration.
In order to utilize the ever changing celestial coordinate system you need to know where north is. I don’t mean magnetic north, I’m talking about celestial north, Polaris to be precise. What I do is look for Polaris in the early evening sky. Once I identify the star I position my base so that 0 degrees is lined up with it. I then look through my eyepiece and make sure it is dead center. Once centered in the eyepiece I go and look at the OTA in relation to the 0 degree mark. Do they match? Am I off a degree or two?
If it is centered I place my marker (pointer) on the base at 0 and go to the next step. Setting circle movable marker. If I am off a degree or so I have 2 options. My first option is to turn the actual base a bit until everything is even. This is sometimes rough if you are on grass. Option 2 is to just move the marker to where the OTA is pointing.
This now becomes your new zero degree mark. I usually get my OTA so close to Polaris that I need not mess with the marker. Now for the cool stuff. Open the planetarium program of your choice and begin.
I’ll begin my test by pointing to the moon or some other well known bright object and center it in the eyepiece. Next i go to my software, choose that object and look at the Azimuth and Altitude coordinates.
Do they match? If not what is off? If altitude is off I check my base for level. If Azimuth is off I check my marker.
Remember that this is not a GOTO setup and that sometimes you may be off 2 degrees or so in your FOV. So long as you are using a low power wide view eyepiece you can adjust easily! I begin with a 2″ 3. I can tell you that after you learn how to setup your system you will see more in one night than you have without it. On a clear, dark night it is very easy to find DSO’s. When you combine this setup with a Telrad or Rigel and some good charts you begin to learn how to star hop as well.
So in the end when your buddies batteries die out on his $2. GOTO scope you’ll still be pushing along to your next destination. I hope this was helpful. Please leave comments or email any questions you may have in regards to this setup.