Friday, January 04, 2008

Meade 12" Lightbridge: First Impressions

My new 12" Lightbridge turned up yesterday morning via Fedex ground delivery. Talk about an exciting day! I raced home at lunchtime to inspect the contents of the two boxes and make sure that the primary and secondary mirrors were okay and intact (I had read about bad experiences in this regard). The mirrors were actually okay, and the scope was very well packed.

While I was supposed to only inspect the boxes during my lunch break, I decided to go ahead and build the base before heading back to the office. This really didn't take long at all, as I had built two Dobsonian bases before (once for my Dad's 10", the other time for my Orion 6".). I was done in about half-an-hour or so. The plywood constructions seemed just fine, and because this Lightbridge was the "Deluxe" model, I had to insert some steel roller bearings on the azimuth bearing, which was really a no-brainer. Having put the base together I quickly assembled the truss tube which again was easy and straightforward. I looked at the beauty of it before having to head back to work. Overall, it was a slick-looking scope. Movements on both axes seemed very smooth, and the scope didn't try and run away from me at all.

Unlike most astronomers who buy new toys, I was blessed with clear skies last night. When I got home I packed the car and headed to the local popular observing spot. I was joined by a good mate of mine, Scott, who brought along one of his high-end refractors and goto EQ mount. It took me no longer that 10 minutes to put the scope together in the field, which includes putting the mirror cell ring into Dob mount, attaching the truss tubes and then attaching the top ring which includes the diagonal and focuser. I had some trouble collimating, but that's because it had been a while. Luckily, Scott was able to help me out and had an excellent alignment configured in about five minutes or so.

For an out-of-the-box experience, the scope performed wonderfully. Movements on both axes were very smooth. I had read the scope was a bit top-heavy, and that when users placed heavier 2" eyepieces into the focuser, the scope would tend to sink a little bit. Meade has apparently gotten around this by adding a tension adjuster to one of the altitude bearings. This worked just fine for me, and I put it on a real test using a 35mm Nagler. The scope pretty much stayed where I wanted it to with each object I viewed. I was also able to nudge the scope carefully when tracking objects with ease, although at times there was just a little stiffness on the altitude axis but I attribute that to an overtightened tension adjustment. So, as far as mechanics go, the scope was great.

Optically, the scope exceeded my expectations last night. I found the crayford focuser to be very smooth indeed. A dual-speed focuser would be nice (I believe this options comes with the 16" model) but the supplied standard crayford fits the bill just right. The sky conditions were about a 3/5, with occasional high level, wispy clouds rolling over from time to time. The first object I went to was M42, the Great Nebula in Orion. It was the best image I have ever seen of the nebula, with the scope clearly showing very detailed nebulosity and clearly depicting the inner trapezium group of stars. Very nice! I then moved onto Mars. For some reason I didn't expect a good view, but with my 10mm Radian (giving me 152X magnification), Mars was big, bright, and had a very nice level of detail. I could easily see some surface features and barely make out the ice cap. The color was also very, very good, giving me a nice orangy-red, sharply-defined disc. I then "surfed" around various Messier objects including M31, M35, M37, M38. All were very clear and sharp. The Double Cluster was exceptional, with pin-point stars and a nice wide field with my 22mm Panoptic. In all, the scope gave me lovely bright and contrasty images, which is exactly what I was looking for in a big light bucket such as this. I did not use the light shroud that I purchased last night, but I think it would help create more contrast when in use. I'll try it next time.

Many people like to modify their scopes. I don't really see much to modify at this point. I would like to replace the standard collimation screws with a Bob's Knobs-type setup which I believe one can purchase for around $50.00 or so. I also wasn't too fond of the included illuminated reticle finder. I much prefer an optical finder, so I'll probably just use the 8*50 right-angle finder I use for my 6" Dob moving forward. There's also the potential to add some digital setting circles but I am in no rush for that. I want to be able to find objects myself for a little while and get to know the sky a little better. Other than that, the scope is perfect as is.

My initial impression is that the Lightbridge is a well constructed, easy-to-use scope that offers wonderful views of the heavens. I was really impressed with the images through it last night, and can't wait to get it out to a dark sky site for some more intense deep sky object viewing. For the current sale price ($850.00) I don't think you go wrong with this 12" monster!

! Feel free to check out my more recent blog posts about performance of and modifications to this scope by clicking this link!

5 comments:

William said...

Beware of the altitude tension adjuster! Unless you're _really_ careful setting the scope down, it can "ride" on the edge, scraping the soft aluminum. I was very careful, but still managed to do it :-( The only safe option is to take it off/loosen it when you take the scope on/off (a real pain). I am buying bucking magnets from partsexpress.com as a way of balancing the scope instead. The tension adjuster is a good option to lock the altitude, and I'll keep it for that.

Phil said...

Thanks for the advice, William. It seems to work just fine but I was unaware that it would scrape the aluminium rings. I think I'll get some counterweights as you suggest.
Cheers,
Phil

astronut said...

Hi Phil,
I've just come across your site, very nice indeed.
We may have met on one of the forums, if not let me say a great report on the 12"LB.
I've had mine for nearly two years and wouldn't swap the time for anything!!
The scopes do work well out of the box, but a few mods will make it much, much better!!
All four end rings should be powder coated matte black, with the current design you have too much white in the lightpath.
Yes, replace the primary and secondary knobs (Astronomy Shoppe or Bob's Knobs)whilst you're there replace the primary springs with the stiffer ones offered.
The original ones are TOO SOFT.
With the stiffer springs your collimation won't wander and you can ditch the locking pins (useless)
To make the focuser more comfortable to use. I recommend that you turn it 45 degrees, this is accomplished by loosening the two grub screws on either side of the base plate.
The 8x50 finder and shroud are a good idea + a dew / light shield.
Cheers, John.
www.macastro.org.au

Phil said...

Hi John,

Thanks for visiting and complimenting my site. Always good to have visitors, especially from Australia. I grew up in Melbourne and miss those lovely skies you guys have. Once a year I get to go back and see some things through my dad's 10" Dob (Bintel).

I am going to get the Bob's Knobs set for the Lightbridge over the next couple of weeks. Will also do as you suggest regarding the springs - good idea and the current locking knobs are annoying.

Love the idea about turning the focuser to 45 degrees! I may attempt that this afternoon...

Thanks for visiting, and clear skies.

Phil

Sky said...

thank you for helping us to get useful and interesting knowledge on astronomy.........