Building a Dobsonian Telescope

[Brian Baldwin]

Many times I have thought about and even talked about building a telescope as a project for myself and my young son. Well last night my neighbor had one out and my family and his looked at jupiter through it and a few of the moons. It was smallish refracting telescope and details of jupiter were clearly not visible to any real extent. But the excitment my son exibited proved to me beyond a shadow of a doubt that talk of the building project had to end and action had to begin. So hopefully with some help from knowledgable members here at this site I will endeavor to build a Dobsonian telescope of enough size to to make out the spot on Jupiter as well as clearly make out some of the closer galaxies.

Once I decide on the specifics of the telescope I will build and photograph it and present the whole "how to" here on this site for others to see how it was done. And while that will be fun, I mostly look forward to seeing my son's face when he gazes upon the raging storm that is Jupiters red spot.

The first thing I probably need help on is deciding on size. Obviously I'd love to have one like that at Lowell's Observatory outside of Flagstaff Arizona but I'll need to be realistic. I've already read that the bigger a telescope is the further it sees into deep space, and the worse it is for inner solar system viewing beyond a certain size. Portability isn't that important to me but it would be handy to be kind of portable. Seeing the planets clearly upto Saturn and their moons are an absolute must. Seeing decent images of the galaxies would be great but are secondary to the planets. So does anyone have any thoughts for size? Keep in mind that I am making a Dobsonian style reflecting telescope and that I'd like to keep the price under $600 for materials. The mirrors would need to be purchased because I'm way too busy to grind mirrors. But everything else I'd be willing to build from scratch.

[American Patriot]

Suggestion Brian....

Go for the biggest mirror you can afford. 8" min and 12 if you can get it then build the telescope around that. I've got a commerically produced 8" reflector, with an equatorial mount, but my second choice was to build a dob. I didn't do it, since at the time I had the money and wanted the quality to do photos with motor tracking.

Unfortunately, I don't get enough opportunities to do that - which is ok, I still use the scope.

Anyway, bigger, in this case is better. More light collection.

Rick

[New Guy]

i have a 6 " reflector eq mount, i'd go for 8" if you can swing it. i might get a bigger one at some point.

for reference, i can see the 4 jupiter big moons and the 2 big bars of jupiter with my scope with my "zoom" eyepiece. sometimes i can make out the red spot if it's really clear.

so go with at least an 8 i'd say.

[Brian Baldwin]

I was thinking along the lines of 14" or 18" myself. The main thing is, I want quality mirrors and optics. Those I will be willing to put forth more money on. Even if it means increasing my budget some. I've read somewhere that bargain priced mirrors are often fuzzy.

I'm glad to see that you guys think bigger is better. Later I hope to add star tracking and photo abilities.