First Light - Review of Antares 200mm Newtonian (Model 520).

This is a first light report covering two outings - a total of 4 hours observing.  The scope came in a surprisingly small box - and in fact the tube assembly does not look large at all when sitting on its own.  I currently have a Celestron Omni 150 XLT, and Orion 100mm Astroview and a loaner 10" Antares Dob.  The scope 'looks' half the size of the 10" when  sitting beside it.



Antares

I've not purchased Antares before and didn't know that much about the company.

But I did know they are Canadian and are not Synta.  I thought I'd give them a chance.

I purchased the Antares Newtonian and Skywatcher HEQ5 mount as a package and received a discount which made the scope a very good deal.


Size

As I said the scope doesn't look that big sitting by itself but once up on the HEQ mount whoa, suddenly it takes on a whole new (large) appearance.  I'm 6 ft tall and the eyepiece is at eye level for me - good for me - but a step ladder for any passers-by who want a look through the scope.  I could see right away that handling this scope - rotating the tube etc - would be a whole different ball game from throwing around the 150mm Celestron Newt.  I've used a GoTo mount before (Meade LXD75), so setting up the HEQ5 was no problem and could be done without actually reading the manual. 



First Light

First light was on the driveway with ugly street lights, but I do live away from any big city, am about a mile from the ocean and my elevation is about 200 metres - the sky is often very transparent.  First target was M42 The Orion Nebula.  After finding the Nebula in the 8x50 right angle, correct image finder, I peeked through my 25 mm Plossl.  The Nebula appeared bright like a large grey cloud.  I switched to the 10mm E.P. for 100x and the Trapezium was well separated.  I could clearly see different colours in the Trapezium stars - according to my Deep Sky Guide they are all white - really!  Then a couple of passers-by did ask for a look through the scope.  I managed without much trouble to loosen the rings and haul the scope around to lower the eyepiece.  The first viewer exclaimed "OMG" and I was surprised at how impressed she was.   The Trapezium stars were a little blotchy but that was down to the seeing - Orion was directly over the roof of my house and I could see the stars flicker rapidly with the naked eye. 



The Moon

After spending some time aligning the mount on Polaris and Aligning the GoTo, I viewed M39 a cluster in Cygnus which resolved very nicely with pinpoint stars.  Then back at Orion I studied Alnitak to try to see its close companion - 4.5" separation I believe.  I couldn't see the companion in the unsteady seeing, but I could see a very faint star around mag 10 at the 5 O'clock position below Alnitak.  So far I had been avoiding The Moon which was steadily rising.  But I decided to slew to The Moon and try my new Antares 4.3mm W70 eyepiece.  The Sea of Crises was right on the terminator of an almost full moon.  The view at 232x was stunning.  I could see small very white mountain peaks just inside the rim of the sea of crises with craters running either side.  The sun angle was excellent and threw great shadows from the crater walls and mountains, the view was outstanding - the 70 degree field was really impressive and the scope was delivering fantastic resolution - it seemed I could have gone way higher in magnification without losing light, but the view was already superb.  I ranged over The Moon into the much more flatly lit areas not expecting to be too impressed because of the nearly full phase, but when I stopped and gave my eye a chance to 'see' there was great detail around Copernicus and even Plato.  Despite being flatly lit I could see the 'relief' of the lunar terrain very well.  I have to look at The Moon more often!  It was 7 below zero outside (it doesn't get that cold very often on The Sunshine Coast) and even my Scottish blood was starting to freeze  


Summary

A summary then of my initial (first ight) impressions of the Antares 200mm Newtonian (Model 520).

The focuser is superb.  2" Crayford with compressing rings.  There is zero play with a very smooth light action. There is a short high quality machined metal extension tube used between the focuser and the 2" to 1.25" adapter.  This is removed when attaching a DSLR to the 2" Focuser.  I found I could not quite reach focus with my Canon Rebel 300D using a 1.25" nose piece on my T-Ring.  I was short of forward focus by a few mm ( I could focus on trees 1,000 yds distant, but not on the stars).  I will purchase a zero profile 2" camera adapter to correct this.  The focuser, extension and adapter all have compression rings.  The optics were well collimated and defocusing Deneb at high power showed perfect symmetry on both sides of focus.  The 8x50 correct image, right angle finder has very nice highly coated optics and a cross hair reticule.  However if you are in the habit of rotating the diagonal around to suit the scope position, the diagonal can easily fall out of the focuser tube.  If the diagonal is not firmly tightened it can be wiggled passed the threads of the focuser tube.


 


The finder bracket looks identical to Synta's but I couldn't fit my Orion EZ-finder (Red Dot) as the Antares finder bracket is narrower by a couple of mm.  Its so close I can fit the Antares finder on my Celestron and Orion Scopes, but my EZ-finder would need to be lightly filed to fit in the Antares holder.  I will probably file the Antares holder instead to make it compliant.  The Antares 200mm comes with a cooling fan installed - very nice.  The collimation screws are chromed steel and look just like the Celestron Omni's.  I haven't touched them yet.  Other than not being able to reach focus with my camera I think the scope is excellent.  It comes with an 8" dovetail rail and tube rings.  The rail is longer than that supplied with the HEQ5 mount however it lacks adjusting screws (to adjust for cone error) and strangely both the rings attachment points were drilled slightly off centre.  I can't figure if this is on purpose to lock the rings at one side against the rail, but it looks odd.  This could create a collimation error.  There's no labelling on the scope to indicate focal length, focal ratio etc and neither is there any scope specific documentation in the box.  But from the Antares website I knew the scope was 1000mm Focal Length, 200mm Primary Mirror, F/5 Focal Ratio and the mirror is guranteed 1/6th wave.  Diffraction limited is considered to be 1/4 wave.



I did want to give Antares a call to ask about my camera problem.  However I found there is no direct contact with customers, you have to ask your dealer.  The scope looks and feels impressive and gave some stunning views of M42, The Moon, M37, The Pleiades and M44 The Beehive.  I've no doubt it will do well on Deep Sky Objects from my local dark sky sites.  I'm looking forward to trying some DSLR Prime Focus imaging with the 2" focuser.  My present imaging platform is the Celestron Omni XLT 150 - basically a smaller version of the new set-up.


Update 07/Mar/09

I've had a half dozen observing sessions with the Antares 200mm now and have been impressed with the views.

My usual favourites are M81/M82, M42, M1, and the like.  A couple of times now I've observed M82 at 133x in a 7.5mm Orion ED Eyepiece and seen the galaxy fill the field of view.  An impressive view from my light polluted backyard.

I have found a problem that's photographic only.  I noticed a prominent diffraction spike on several photos of The Horsehead Nebula.  The spike extended farther than normal and flared out towards the end.

I looked down the scope tube and found the secondary mirror was being held in place by some kind of mirror housing.  The housing unfortunately has a bright silver screw and clip attached to its outside and is in the light path.  But worse, the clip hooks around the edge of the secondary and holds it in place like a metal finger - this too is in the light path.  I looked at our older club 10" Antares Dob and found the older style is totally different and secures the mirror from its centre with nothing in the light path - the same with my Celestron Omni XLT.  By coincidence I was down at VTC yesterday and bumped into Glenn Speers (Antares Director).  I took the opportunity to mention this mirror glitch to him .....  I will try some flat black paint and hope not to get any on the mirror!




Update 12-Feb-09

My zero profile camera adapter finally arrived and I was able to shoot some test images using the Antares 200mm at prime focus. 

I used Sirius to focus the camera and the scope was riding on an HEQ5-Pro.  Here are some raw images and some first pass processed versions just to show what the scope threw up on 2 minute exposures with a  Canon 300D DSLR at Prime Focus.



Raw Frame of M42 and NGC1977


Dark Frame Subtracted and Unsharp Masked

A Little Overprocessed!







Raw Frame of the M81 Galaxy in Ursa Major.




Dark Subtracted - Stacked 2 Frames - Balanced - Needs Blended!


More recent image of The Horsehead

Note the long diffraction spike running under the horsehead.


M81 and M82 from the backyard.

Visually the galaxies were also

Impressive.




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