Apertura AD12 - Great things come in large packages

Posted by John Kramer   10/06/2011 03:30AM

Apertura AD12 - Great things come in large packages
DISCLAIMER: OpticsMart announced themselves as a new astronomical telescope and accessory vendor through contacting me via email, as they heard of my radio show on BlogTalkRadio. I offered them the opportunity to give them an unbiased review of their Apertura AD12, which they graciously accepted. This scope is a loaner from OpticsMart for the specific purpose of this review, and I by no means have any professional association with OpticsMart.



They say good things come in small packages, but for the Apertura AD12, small doesn't apply. You just gotta love large dobsonian telescopes; no other scope permits you the simplicity, affordability and light gathering capability as a dob. It's all about what's at the eyepiece with these scopes, and that's exactly where they deliver; a fantastic visual observing experience for those of us that long for those faint fuzzies. Thus, when the opportunity presented itself evaluate a new line of scopes exclusively offered by OpticsMart, I jumped, and jumped into the deep end so to speak, asking for and receiving no other then their top-of-the line, large dobsonian, the Apertura AD12 with the "Tweaker's Dream Package".

So what is an Apertura AD12 anyway?

The Apertura AD12 is a 12" f5 dobsonian reflector with a well thought out altitude bearing system that permits the scope to be properly balanced depending on your eyepiece selection, a very important feature with dobsonian telescopes. OpticsMart takes things a bit further however, and offers the "Tweaker's Dream Package". They no doubt listened to amateur’s and researched what tweaks most amateurs perform on their dobsonian telescopes that would make these scopes more functional and enjoyable to use out in the field, thus offering this special set of preinstalled “tweaks" onto their exclusive line up of Apertura dobsonians. This option makes your typical 12" f5 dobsonian into a truly optimized 12" f5 dobsonian. The included components of the "Tweaker's Dream Package" include; Ultra-Smooth Secondary Washers, Soft Grip Guide Knob, Collimation Thumb Screws, an additional 5 Hole eyepiece tray, and last but certainly not least, Fidelio velvet lining.



While there will no doubt be opinions that will float out there on the benefits of some, if not all of these tweaks, the fact that OpticsMart even offers this as a PREINSTALLED option is fantastic and shows a nice level of commitment and openness to the amateur astronomy community by a vendor, and I really like that. Regarding the tweaks, I'm of the opinion that the flocking is a great help to reduce stray light and increase contrast, even my own 6" dobsonian has a bit of flocking added. The extra 5 hole eyepiece tray is nice, it allows for you to have a diverse selection (5-1.25" and 3-2") of your eyepiece's conveniently on the base for easy access. The diagonal washers are ok, but the collimation thumb screws are a big hit with me. Nobody wants to chance dropping an Allen wrench or screw-driver down the tube one night while your trying to collimate your scope.

Physical Components

Let's talk about what's included with the standard Apertura AD12, and the physical characteristics of this scope. I'll put the specs from the manufacturer below for you to review.

Features included in the base package:
2 inch, dual-speed Micro 10:1 Crayford style focuser, with 1.25" adapter
Right Angle Correct Image (RACI) 8x50 finderscope
1.25" 9mm Plossl eyepiece (high-power) with 52 degree field of view
2" 30mm SuperView eyepiece (low-power) with 68 degree field of view
Laser Collimator (1 battery included)
Battery operated primary mirror cooling fan (8 AA batteries required - NOT INCLUDED)
Dobsonian base with roller bearings for azimuth and sealed ball bearings for altitude, resulting in super-smooth adjustment in all dimensions
4-slot eyepiece tray

Technical Specifications and Dimensions:
Primary Mirror Diameter: 12"
Focal Length: 1520mm
Focal Ratio: f/5
Optical Tube Length: 57.25"
Fully Assembled Height: 63.75"
Optical Tube Weight: 47.8 lbs
Base Weight: 38.3 lbs
Fully Assembled Weight: 86.1 lbs

Be prepared for a LARGE scope. If you think 87 lbs is a lot, your right. The OTA isn't bad at 47lbs, but it's the 57" length that makes it a bit challenging to move around. If your not going to be observing from your home, and plan on taking this scope to a dark-sky site often, you better be prepared physically to haul it out and about. You will also want to ensure your vehicle has enough room to safely transport this size scope to and from your observing session, and don't forget all the other secondary equipment you'll need as well.

The scope arrived in overall great shape, with only a few minor scratches on the base boards, but all seemed to be on the interior, so no worries. The OTA had a few blemishes that looked like lint or something during painting, but these were only about the size of a quarter, certainly nothing that distracted the overall beauty of this scope when fully setup, and it is one gorgeous telescope when fully assembled. (Figure B)



I was pleasantly surprised that the OTA shipped almost entirely assembled, so you only have to install the altitude bearings and that's it, so that was nice. The base assembly was easy enough; I think it took me about 20 minutes from start to finish following the step by step instructions. By the way, the best feature of the base was the roller bearing on the azimuth (Figure C). I wish ALL dobsonians included this mount versus the Teflon in many dobsonians. You see, those Teflon bases are ok, but I find you need to exert more pressure to initially nudge the scope, thus inducing some issues keeping the object centered, especially at high powers. This roller bearing on the azimuth base means a more fluid motion for tracking, and you will appreciate that when viewing at higher powers, trust me. So if you never put together a dobsonian, don't let it intimidate you at all, it really is a piece of cake, even for this AD12. The rest of the assembly took about another 20 minutes if that, with most of that time experimenting a bit with the adjustable altitude bearing assembly, since this was the first time I had a chance to see this in action up close and personal.


OpticsMart includes a decent amount of accessories with the telescope. (Figure D) The 8x50 RACI finder is a big help in star-hopping. Two eyepieces, a 30mm Wide Angle and a 9mm Plossl give you a wide field and medium power views. The Crawford focuser (Click for Image) can accommodate 2" or 1.25" eyepieces, and has a nice 10:1 micro focuser with non-marring compression rings too. OpticsMart also thought of collimation for the AD12, and included a laser collimator that helps you take guesswork out of proper collimation. Also included with the base package is a fan (4 AA batteries not included) to ensure your optics reach thermal equilibrium as quickly as possible. Believe me, you will want to ensure this light bucket performs at its best optically; a 12" scope can deliver jaw-dropping views if the optics are up to it.






First Light


Oh my ,oh my, I LOVE the smooth motions of this scope! The azimuth bearing that resides on the base makes movement buttery smooth, and you can adjust the tension to your individual liking. The adjustable tension on the altitude bearings are also nice and smooth (Figure E). I had high aspirations for the adjustability of these bearings, but never quite realized until I received the scope that the bearings don't adjust on the fly, meaning once the OTA is on the base, to adjust them, you need to remove the OTA and readjust. This can be a pain in the neck, well actually your back for such a large OTA as the 12", so my recommendation is to attempt this before ever venturing out with the scope and with your most often used eyepieces. I achieved an acceptable level of balance with my 1.25" eyepieces, even the included 2" 30mm, but add my 24mm Meade UWA that I affectionately call the "Eye-Grenade", and the scope wants to tilt down, even with the tension knobs as tight as I can get them. Sure you can add clip-on counter weights to the rear of the scope I'm sure, but being that this is an evaluation model, I didn't have that option available, so you may want to include weights as a must have accessory if you have heavy 2" eyepieces. Interestingly enough, I searched online for another possible method of balance or tightening up the tension knobs, and found an interesting link. (http://www.cloudynights.com/item.php?item_id=2492). Now I have no way of know if this fix will work, but worth a try if you decide the AD12 is the scope for you and have similar balance concerns with your heavier eyepieces.

Optics

When you add up the sheer joy of ultra smooth motions on both axis, and good optics, you're bound to enjoy yourself during a night full of visual observing. The Apertura AD12 delivered just that experience. My star tests showed good results, with concentric rings that matched closely on both inside and outside of focus. I'm no optical star test expert however, so most of my tests and evaluation of the optics will be gauged by the initial visual appearances of select deep-sky and planetary objects.

I own two 8" CAT's, and the light gathering capacity of the 12" versus those 8" was very noticeable, as one would expect. Globular clusters were outstanding, more then fuzzy balls with some resolution; these were glorious spherical balls of stars that you could see to the core. M2, M13, M15, M92, M4, M80, M71, M72, M22, all gave me outstanding views with my Meade 14mm and 8.8mm UWA eyepieces. Planetary nebula, another favorite of mine, were easier to detect, with M57 & M27 showing noticeably better then my smaller scopes when I crank up the power. Open clusters M11, M45, M36, M35, M37, NGC 457, and the Double-Cluster were outstanding. The Great Orion Nebula, M42, was obviously great as well, with 6 Trapezium stars snapping into focus using a high power eyepiece.

Another very interesting benefit of the increase of aperture a 12" offers is how improved the colors of the stars show up. I recall when viewing the Double-Cluster in particular, I noticed more orange stars in the field of view than I recall seeing before. Intrigued, I just started to slowly scan around and noticed that the stars indeed seemed to be more "colorful". Not that stars changed from white to orange, but stars that are white seemed slightly bluish now, stars with subtle tinges of blue or yellow were much more noticeable, and stars hinting of orange were now much deeper shades of orange, some approaching red now. Alberio's color contrast was even more striking in this size aperture. A quick search on the forums confirmed what I had visually experienced; larger aperture scope naturally collect more light, and thus bring out the true colors of stars better then smaller aperture. What a pleasant surprise that turned out to be, since colorful doubles are also a favorite object of mine. I must admit however, that my star hopping skills are woefully rusty, and didn't spend too much time at all tracking down doubles, with this aperture, better things lie in store. I'm sure with more practice my star-hopping skill would improve, especially using 8x50 RACI and included 30mm SuperView eyepiece, because they did permit finding deep-sky objects fairly easy.

Back to other visual observations with the AD12, and in particular a memorable observation. As the night progressed from resolved balls of light, rings of nebulosity, to colorful clusters and pairs of stars, I noticed that the king of the planets, Jupiter, had finally rose high enough to permit an adequate view. Nothing quite prepared me for the view I was about to have, for when I placed Jupiter within the field of view of this light bucket, and I focused with the very smooth dual-speed Crayford focuser, I was greeted with my best view I have ever had of Jupiter, bar none. The resolving power, the sharpness and brightness of the view, the way the GRS popped out, white wisps coupled with the subtle yet noticeable banding all the way to the poles, the wealth of detail in the SEB, and the dark features in the NEB simply made me gasp. Then I put in my 8.8mm UWA. WOW, superb, what a view! "Try it with a Barlow" I thought, sure enough, the Barlow went in and there was the view, holding up quite nicely. "Try it with a 6mm ORTHO and the Barlow" a voice said, but surely that would be insane I thought? Well, the view held up ok enough, but the narrow field of view didn't permit me to really get an adequate view of Jupiter. What I did see was fleeting disk of a planet with noticeable detail, but not better then the 8.8, so back to the 8.8mm and the fantastic view that presented me. The seeing was no doubt good, and coupled with the 12" aperture of the AD12, the view was stunning. This view almost single-handedly confirmed that the optics in the Apertura AD12 were very good indeed, in my opinion. Of course my previous star tests hinted at this as well, but I almost decided right then and there, with Jupiter shining in glorious detail, that I needed this scope. I thought that surely my girlfriend would appreciate sharing even more space in our bedroom for another scope, albeit a monster like the AD12. But calmer minds prevailed; I guess the thought of gaining a 4th telescope at the price of loosing a girlfriend has a way of doing that to a fella. So I took a deep breath, told myself that I just don't have room for another telescope (at the moment) and to just immense myself back into the view that I am experiencing right now, and enjoy the ride. Enjoy the ride I did!


Final Thoughts

The Apertura AD12, in its base configuration ($629.98), is a great value in a dobsonian telescope that offers sharp optics and superb motions on both axis. Add the "Tweaker’s Dream Package" (add $149 to base price), and you make a wonderful scope even better. If I had only one critique of the scope, it's that base could be a bit stiffer to reduce some shakiness when your viewing through the eyepiece and centering objects at the same time. I'm confident however that when you're an owner of such a scope, you can find creative ways to shore up the base if you find the degree of vibrations objectionable. Now if you'll excuse me, I need to convince someone that a 12" Dobsonian will blend in beautifully to our bedroom decor.