QUESTIONS & ANSWERS

Are you interested in truss tube dobs? Below you will find answers to some common questions. And if you won't find what are you looking for, don't hesitate to ask me directly :-)

? OK, so what does such telescope cost?
Price of the custom built telescope strongly depends on the configuration (optics, components used etc.). Generally I can say that the price of my smallest 6 inch dobsonian is 2 to 3 times higher than the price of common mass produced telescope. Price of the 16 inch truss Nitelite dob is then about 30% higher than the price of common telescope of comparable aperture. Chinese production slashed the prices of amateur telescopes to levels that would have been unbelievable 20 years ago and allowed observers to obtain instruments of some nice apertures. Today is a great time for the amateur astronomer (apart from the ever growing light pollution :-( Custom built telescopes remain an alternative for those, who require something that common mass produced instruments cannot offer.

? What makes the telescopes like Nitelite better than a common mass-produced scope?
Now that is pretty simple - Nitelite is a custom built telescope. It means that it can be executed to fit your needs, something that is not possible with a big brand scope. Of course, the most important advantage is its size and portability. Usually the bigger is better when it comes to the telescopes. But it is not always true, as realizes everybody trying to squeeze his big gun into the car :-) Today, the urban sky is so damaged by light pollution, that most observers have to drive to enjoy dark skies. Common telescopes, even the "collapsible" ones, usually take most of the trunk and the rear seats thereto. Truss-tube structure of Nitelites allows to collapse even big apertures into very reasonable package, making the transportation a non-issue. Imagine that you need to fit 3 telescopes, 3 people and the baggage for two-week trip into a common car. Unreal? Not so much with the Nitelites! Weight of the Nitelite telescopes is approximately one half to one third of what is usual among common dobsonians. The smallest Nitelite 6 and 8 meet the requirements for a cabin baggage if you need to travel by air.

? Looking at the open structure with single secondary ring, the secondary mirror must be very prone to dewing, right?
Because of rather minimal shielding, the secondary mirror in open structure telescopes is prone to dewing more than in solid tubes. But it is certainly not any rule that you always end up with dewy secondary! A lot of nights is without any problems, even if the humidity is rather high, just be carefull not to breathe at the optics. And finally, there is always a very effective solution: secondary heating. I have installed several units from Astrosystems and they really do what they are supposed to do - keep the dew away for the whole night. Highly recommended!

? What about gathering dust on the mirrors in this open structure?
To be honest - especially the primary mirrors in the open structure telescopes seems to atract dust much more than optics in solid tube telescopes, even if you consistently cover the mirrors when the telescope isn't in use. If you must have perfectly clean optics all the time, count that you'll be cleaning the mirrors rather frequently. But believe me - for the observing itself you definitely do not have to have perfectly clean optics. Most people don't notice the difference in the image even if the mirror looks really bad at first sight.

? How do you solve the problems with stray light?
Good contrast is a key feature of the telescope and therefore it is vital to reduce as much stray light entering the eyepiece as possible. Open structure telescopes are clearly disadvantaged in this regard compared to solid tubes, however with proper baffling and blackening of the parts near the optical trail even the truss telescopes can achieve very good contrast. Most important is a baffle opposite the focuser that needs to be as black as possible. I use black velour flocking paper on the inner surface of the baffle, reflecting almost no light. Directly visible parts of the secondary assembly (including edge of the secondary mirror) and the mirror box are flat black painted. Truss tubes can be covered by black matt plastic. Good idea is using a shroud, which also helps to keep the optics clean and to certain extend prevents dewing. Of course - the best solution is to chose observing place with no direct light visible (it helps your eyes to become dark adapted, too :-)

? How difficult is assembling/disassembling of the Nitelite telescope?
It is very simple, after you get to know the telescope, you will be able to put it together in less than 10 minutes, including the collimation. No tools needed.

? Wouldn't it be better to use roller bearings instead of the teflon?
I don't think so. In my telescopes, I use well proven combination of high quality coarse structured Formica laminate (not to be confused with inferior laminate found on most commercial dobs) sliding on teflon pads. Movements of the telescope are very smooth and it's no problem to track objects with high power. You can easily operate the scope with a touch of a hand.

? Is it possible to have the scope equipped with a DSC / GOTO?
Even though I didn't installed a digital setting circles on any of my telescopes yet, I see no problem in that as it is pretty straightforward. Full GOTO is a different story - it would require quite a lot of work and testing and it certainly would't be cheap. It might be an interesting project, but for now I want Nitelite telescopes to stay rather simple, reliable instruments.