Apertura AD10 4.9 vs Orion xt10 4.7

[starrycanvas]

Hi there!

I have the option of buying an Apertura ad10 with tweaker's dream package, azimuth setting circle, and telrad for $525.

or Orion xt10 with 9x50 finder scope, 3-element barlow, original lenses, and an Orion bag for $400.

 

Both are in excellent condition.

My question is:

As a beginner, am I better off with a f4.9 or would it be best to go ahead and start off with a f4.7? I would like sharp contrast and would prefer to not spend on super high-quality lenses.

Also, would I see experience coma with f4.9? Or barely noticeable to a beginner's eyes?

 

Or perhaps, is one a much better deal than the other?

[jetstream]

Hi Starry, its hard to say- the Apertura uses a GSO mirror and the Orion is a Synta, both good. The company selling Apertura no longer does so...and Orion USA doesn't sell replacement parts to non original owners ( I think).

I like being able to tighten the dob tube up, which the Apertura does I think- is the XT10 the model with the springs on either side? Coma seems to diminish over f5, Mod John isn't too bothered @ f5.3 using his Hyperwides, that can "show more" coma. Can you try the scopes out first?

[starrycanvas]

The xt10 has the springs on the sides, yes.

They're scopes for sale on craigslist so I can't really try them both out. But I think I'm going with Apertura ad10 on account of all the "upgrades". The quality also seems better.

Here is what description reads: 

Weight 60 lbs.
Aperture 10 in.
Finderscope 8?50
Optical Design Reflector
Focal Length 1250 mm
Focal Ratio f/4.92

It comes with the basic package of:

Hand-adjustable knobs on primary mirror for easy, no-tools collimation
2 inch, dual-speed Micro 10:1 Crayford style focuser, with 1.25" adapter
Right Angle Correct Image (RACI) 8x50 finderscope
1.25" 9mm Pl?ssl eyepiece (high-power) with 52 degree field of view
2" 30mm SuperView eyepiece (low-power) with 68 degree field of view
35mm Extension Tube (used to provide extra back-focus for eyepieces that need it)
1.25" Moon Filter
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

The Tweakers Dream Package includes: Ultra-Smooth Secondary Washers, Soft Grip Guide Knob, Collimation Thumb Screws, 5 Hole eyepiece tray, and last but certainly not least, Fidelio velvet lining in the OTA to darken it and improve contrast.

I'm also throwing in a Setting Circle, which comes with a red clip-on light.
There is a strip of velcrow on the lower base of the OTA, I used it to hold my Nexus 7 to help with finding things. It's easily removeable. There is also 2 velcrow straps atttached to the OTA to help move it, makes it so much easier to handle. I'm also throwing in a Telrad! 

I'm also throwing in the Celestron 21024 FirstScope Telescope and the Eyepieces that go with it!
Plus an Alt-Gauge (seen in pics)!

[jetstream]

These scopes are held in high regard by many on CN, and has many desirable features. I havn't heard of the mirror cell springs needing replacing (stiffer) on these scopes. If it were me I would want pictures of the primary and would ask the seller if he cleaned the primary and how he did it. Whats the reason for selling? another possible question Starrycanvas.

Ask about that Nexus too... did he modify the scope for the DSC? (digital setting circles). A Nexus would be nice...

[starrycanvas]

The owner says he simply doesn't have time to use it anymore. He also says there is nothing wrong with it.

Of course, I want to be able to inspect it myself when I go to pick it up. What should I physically check for to make sure that the primary mirror and all are in good condition?

Otherwise, I don't believe it was ever set up with a digital setting circle. I don't have a Nexus, but I do have a Nikon DSLR

 

Thanks for your help in advance!

[jetstream]

The best test would be to try it out at night with an experienced Newt ( dob) person. Any issues with the optics will show up there if the person knows what he's doing.

One of the major things with mirrors is how they are cleaned, the surface can be easily ruined. Shining a flashlight across the surface reveals much....but the odd "sleek" from the manufacturer usually results in no image degradation.

Ask him how much mag the moon and planets will take in this scope- a reasonable set of optics in that scope should provide razor sharp lunar views over 200x...

On the back of the mirror cell look to see how the screws are and also the ones that hold it to the tube-are they marred? Then just move the scope around on it axes to see if its smooth and check its general condition. I may ask a couple other members for their opinion.

Make sure you bring someone along.....

[starrycanvas]

Thank you for the advice!

Oh, no worries - definitely went with a friend. So it turns out the dob was in excellent condition. He had never attempted to clean the primary mirror, and always had the opening covered. No screws were marred either!

 

I love how it looks. 10" dobs are big! But look like a million bucks. Can't wait to get started

[jetstream]

Awesome!

Eagerly waiting reports!