by Jon Ruyle
On Monday, I received four large packages at work. Hmmm, I thought. What can they be. I opened them up, and... hey! A 12 1/2" Starmaster EL!
So went up to FP with my wife and a friend for first light. Out of a warm car into the bitter cold, ate dinner and pointed it at Jupiter which was pretty low in the sky. Blurry. Blurry. Blurry, and then for a second- more detail than I have seen on Jupiter for a long time. Then more blurry.
I went to deep sky- bright stuff so I wouldn't bore the others. We enjoyed several of the usual showpieces, but the two surprises were M3 and M51. M3 was resolved right to the core at 130x, and the spiral arms of M51 at 59x and 130x were obvious. The improvement going from 8" to 12 1/2" is much greater than I expected, and the views were better than I remember in friends 12 1/2" f/5 Cave at Mt. Pinos a few years back. Maybe my eyesight is improving with age (more likely, my memory is deteriorating)
Just before leaving I tried a star test at 130x, and saw what I believe were tube currents. The scope had been out for three hours, but it had come from a warm car, it was really cold out, and there was no fan. Though the deep sky images were great, I figured the scope would have performed better on Jupiter if it had a fan.
Tuesday I set the thing out about two hours before sunset, attached a small fan to the thing with rubber bands and let it run. When it got dark, I pointed at Jupiter. The seeing in my yard is such that I can rarely go above 130x with my 4", so I figured the 12 1/2" would have an even tougher time. Well that was wrong. First at 130x, then 176x, then 212x. At all powers, it was blurry about half of the time, and sharp the rest. The NEB and SEB were shapely and a smaller belt was visible next to each. Cloud detail was visible between the main belts. The fan seemed to have helped, but maybe it was just good seeing. In any case, it was by far the best view of Jupiter I have had from my back yard (I usually feel lucky if I can glimpse a third band at all).
I then looked at a few bright galaxies. Man did they seem bright- I am really used to using the 4" back there. NGC2903, M95, M96, and M105 almost seemed like they do with the 8" from a dark site (not really, but I am excited about my new scope so bear with me). Bright with obvious central brightening, gradual and diffuse in the case of 2903, and tight or stellar in the Leo galaxies. I was even able to spot NGC3226 and NGC3227, both of which escaped me on previous attempts from home.
It seemed like I was just out for a couple of minutes, but suddenly it was 9pm and I had to run to Pizza Mania to pick up dinner before my wife returned home from work. Do clocks run faster while telescoping than they do at other times?
After two short sessions, it seems that the scope will far exceed my expectations on planets and will allow me to see deeper from home than I was able to before. Another plus is that the secondary holds collimation very well. When I set it up for the first time, the secondary was almost dead on. The users manual said it shipped collimated and so should not need adjustment, but no way did I believe that. I don't know if it is because of a good spider/secondary holder, the fact that the whole upper assembly is one solid piece (as opposed to a truss arrangement which breaks apart), or simply because of the small size, but for whatever reason, it seems like I will almost never need to adjust the secondary (in contrast to my other dob, which needs secondary adjustment every time it is set up). Since there is no sling to adjust, the only collimation that will be regularly needed is the primary collimation with the knobs in the back.
On the negative side, the scope as shipped does not come with a fan, and my initial impression (maybe wrong) is that it needed one. Adding a fan was pretty easy, so that's no big deal. Also, the scope is way out of balance unless there is an eyepiece in place (even with the paracorr)- so it is a bit tough to switch eyepieces while keeping an object in the field. The trick I have been using is to balance the new eyepiece on the back of the secondary cage, take the old one out, put the old one on the secondary cage, and put the new eyepiece in (less trouble than it sounds). The only problem is that sometimes the combined weight of the eyepieces is too much and causes the scope to drift down. It is a bit annoying- but I guess that's what happens when you want to use heavy eyepieces with a dob this size. If I add weight to the secondary cage, the scope won't balance with the 20mm Nagler. Maybe I should do it anyway.
Another cause for concern is that while the lack of a sling means that there is one less component to adjust, it also means that the mirror rests on two pins. The images seem fine, so I don't think it's a problem. Still, I'll watch for strange shapes in the star test.
The complaints are minor, and the views are even better than expected. I am happy happy happy! Except... it's raining. Did someone get some new equipment?