Posts Made By: Marcin Klapczynski

Hi guys! Remember me? I am the guy who was bothering you for the last 6 months while grinding, polishing and figuring 8" mirror. I finished my scope today, it still needs some minor improvements and painting.
I had a pleasure to see some breathtaking things this night, even in light polluted Chicago! I couldn't say a word for several minutes seeing the majestic Saturn with rings and moons for first time in my life, I was just bedazed, and then hurrying through the sky Jupiter for a dessert! God, I can't wait until I take my new toy to some dark sky places...

So anyway, I am proud of myself and I want to thank you for your priceless advice and support. Without you I would just throw away a mirror blank and polishing lap through a window after clueless hours of painful figuring.
I would like to thank especially Tom Simmons for hand holding and being a patient teacher; Bob Chester, William Earl, Doug Scobel , Jason Lane, Floyd Blue for great tips and support and all other guys from Astromart forum I missed. Really it's good to know that you guys are around. I hope we'll meet some day on a star party!

I attach some pics of my work.
Dobsonian mount was built based on Ray Cash-Le Pennec's plans, which can be found here:http://pages.sbcglobal.net/raycash/manualv2.pdf

Some telescope specs:
Primary: 203 mm (8"), F/5.87, 1/12 lambda error
Secondary: 39mm (1.55")
Sonotube baffled based on Newt sofware with insulation foam strips
Dobsonian mount made of plywood
Open mirror cell, cooling fan friendly
Low profile threaded focuser made of plastic plumbing parts

Hi,
I am a newbie and looking for a high power, good quality eyepiece for a planetary/deep space object viewing for less than 100$
After some research I found one from Orion:

3.5mm Orion Stratus Wide-Field Eyepiece, FOV:68°, ER: 20mm, mag: 341x, $95

But then I found online some enthusiastic reviews about Burgess Planetary series:

4mm Burgess/TMB Planetary Series, FOV:60°, ER: 16 mm, mag: 298x, $99

Although numbers look more tempting in first case, I know that somtimes they aren't everything. Do any of you have one of these? Can you advise me which one to choose?

And another thing - the theoretical maximum magnification of my newly built scope is 400x. Is 341 x (in case of Orion eyepiece) in a 'safe limit'?

Thanks

Hi guys! I have recently finished my scope and had a chance to use it in the city only. I am planning to go to visit my family in suburbs and show off with my new toy. 8)
How do you carry your tube? Should I take out the primary mirror with the cell or keep it inside? What about the secondary - it would be kind of hassle to unmount the whole spider...
How does one travel with a dobsonian scope? :S

Hi,
Before I fixed my telescope tube to the carriage box I had balanced it very carefully with all elements attached - the mirror cell, the finder, the spider and the eyepiece. At the end everything was perfectly balanced indeed, but once I added a barlow, the tube goes slightly down by itself, especially when I try to observe objects that are just above the horizon, like rising Jupiter.

How do you keep balance of the tube of your dobsonian? Do you add some weights on the other end?
Thanks for any tips

Hi guys,
I am looking for a webpage, a magazine or a book that has pictures showing reflector telescopes performance comparison based on a primary mirror aperture. I am looking for pictures that are real through-eyepiece views or are processed the way to show the view using aperture of 6", 8", 10", 12" and so on.
Thanks in advance

Hi guys!
Some time ago I was asking about a balance issue, because once I added a barlow to my ep, front of the tube was going down while observing objects low on the sky. I tried to cut and reposition teflon bearings but it helped just a little bit.

I also installed a new focuser, which was even heavier then my old one, made out of plastic plumbing parts. Because the focuser was also higher I had to push mirror up in the tube, which all together caused even more annoying balance problem.

Check out the attached pics. I added two springs that increase tension while the tube goes down. Springs by themself appeared to be not sufficient enough and tensioning them too much caused some rough movement. So I added some weight at the bottom part of the tube, simply fastening heavy bolt with nuts and washers there. Mayby it doesn't look too good, but it works great with any combination of barlows and eps. No unwanted movements and smooth action!

Hi everyone!
Do you know any useful links or books about motorizing a dobsonian telescope? I have seen many post here about motorizing big truss tube dobs.
What about 8 inch close tube dob? Is it worth starting this project... or build another scope
Thanks

I am planning to buy narrowband and oxygen-III filters. Do you have any suggestions which brand to choose or do you know some webpages with reviews?
Thanks

Try 1/3 center-over-center stroke with 80% TOM and 20% MOT of your total work time. Your W stroke is probably denser in the middle than on the edges too, that is why you were getting this volcano crater
Hope this will help, good luck!

Is anyone from Chicagoland gearing up for a Messier marathon? I was thinking Green River State Wildlife Area tomorrow but the forecast isn't really encouraging (unless it'll change tomorrow):
http://www.cleardarksky.com/c/GrnRvrWILkey.html?1

There is still a chance for decent Mm next weekend, but this Sunday is new moon, so conditions would be perfect....

Any other places in Indiana or Michigan (2-3 hrs drive)?

Regards

EDIT:
Forecast at Chicago tribune is more promising:

Saturday Night...Mostly clear. Cold with lows around 20. Winds becoming light and variable.