janoskiss
21-12-2006, 12:46 AM
Got my new Saxon (aka Skywatcher) 10" Dob today! :) Purchased from The Telescope Shed (John Izzo).
Here is a first look preview, fresh out of the box! No first light yet though.
Brief summary: I am very impressed with the Saxon Dob. Better built and better thought out than the GSOs, with some very nice, indeed surprising, attention to detail. Of course, like all off-the-shelf scopes, it's not perfect, but so far I am very happy overall.
In more detail:
-> Photos to go with most of this so check them out.
The GOOD:
Teflon washer around centre bearing included. And it's the right size!! No milk jug washers for this baby! :D Centre pivot bolt is also nickel plated.
Great big beefy collimation and locking screws with nice easy and smooth action! Springs are plenty strong enough to hold the weight of the mirror without sagging. No change in collimation after tightening locking screws. No discernable shift in collimation from 25deg to zenith. A small shift observed going from 25 to 0 degree altitude (locking screws loose or tight makes no diff).
This is what I do with any Newt I buy: Pull the mirror cell out. Undo the mirror clips. Loctite the screws (so they don't fall out in transit) and put the clips back in very loose so they apply no pressure to the mirror. Well guess what? That is already done on the Saxon! There is about 0.5mm clearance between the mirror and the clips, and the screws are loctited in place. I could rotate the mirror in its cell which is how it should be. There are six clips, which IMO is an overkill, so I removed three. There was no markings on the mirror under the clips I've removed.
The primary mirror looks immaculate. No chips in the sidewalls like on both my GSOs (not that this would affect the views but still it's nice :)) The mirror I'm told is made of pyrex glass, and made in the US (the scope itself is made in China). I would not know how to tell pyrex from the rest, but the glass looks clear, while my other scopes have glass that has a greenish tint.
Centre spot precisely placed in centre, to the nearest 0.5mm I could measure.
No plastic housing for secondary means the central obstruction is just the mirror and nothing else. Central obstruction measured at 50-51mm. Aperture measured at 255-256mm => Central obstruction no greater than 20% (compare with 25% for GSO Dobs).
The secondary is glued in place on a smaller holder behind it, so there is no mirror clip and no retaining screw in the light path. All screws affixing spider to mirror holder are also well behind the secondary, making for a nice clean circular central obstruction.
Eyepiece holder on front of the base not on the side, so no more worrying about kicking my EPs or smokers looking through my scope inadvertantly using my Pentaxes as ashtrays.
Heads of screws for holding mirror cell and "spider cell" (?) to ends of OTA are sufficiently large to properly cover the holes in the OTA. This is not the case for GSO Dobs (incl. Lightbridges I've looked at) where the screws heads are barely larger than the holes. It might not seem like a big deal but what I am consistently seeing in this scope is attention to detail. Good!
Instructions are good. I haven't read them extensively because the pictures tell the story well, but when I needed to refer to them I found what I was after. All tools are included, including philips head screwdriver, allen keys and two spanners. The screwriver was a little undersized for the screws for the feet though (can make do but better get a beefier one for these).
The finish of the components is very good. The base is high density chipboard, but it is very well laminated. There is no bare chipboard exposed anywhere on any surface or edge, and the laminate/edging is well and truly stuck onto the boards.
Paint looks good, and tougher than the coat of silver-grey on most of the GSOs. But I already knew that. ;)
The two silver top plossls: 10 and 25mm. Good starter pair. I have used this type of EP before and they are quite nice. They hold up well against top brand plossls.
The scope can be picked up and carried as a whole unit by the tensioner handles. Not as easily as the 8" but still quite grab-n-goable.
The not so good and the the indifferent:
Rack and pinion focuser and it does have a bit of backlash. It has a larger footprint than a GSO focuser, so the GSO crayfords will not bolt on. I am not sure if there is even enough room around the hole in the OTA to drill holes for fitting the GSO focuser. You can buy ED80 style Crayfords from Saxon that bolt straight onto the bracket, but I would prefer the GSO with the 10:1 geared fine focuser.
Secondary collimation needs allen key.
No bump cushioner for OTA at zenith. My first mod: a bit of felt on the base.
Altitude bearings are "sticky". They squeak and creak before they get moving smoothly. Mick Pinner recommended a bit of graphite. Going to try that tomorrow. I will also consult with John Izzo and Daniel(sun) to see if they have any tips. Teflon might be the go (the big bearings are nylon).
Focal length is just 1200mm. With an aperture of about 255mm, this makes the scope an f/4.7, which means it will be extra fussy with eyepieces. The OTA is nice and compact though and I already have EPs that will work fine at f/4.7, so I don't mind.
The OTA sits quite high in the base. You can see it in one of the photos next to the GSO 8". There is heaps of room underneath. I'd prefer if it sat closer to the ground, which would make the whole setup more stable and seated observing near zenith easier. I might just have to do something about that too... :confuse3:
Oh, and no ebony star on base board! But who am I kidding, right?
That's about all I have to say about this scope till first light. :)
Here is a first look preview, fresh out of the box! No first light yet though.
Brief summary: I am very impressed with the Saxon Dob. Better built and better thought out than the GSOs, with some very nice, indeed surprising, attention to detail. Of course, like all off-the-shelf scopes, it's not perfect, but so far I am very happy overall.
In more detail:
-> Photos to go with most of this so check them out.
The GOOD:
Teflon washer around centre bearing included. And it's the right size!! No milk jug washers for this baby! :D Centre pivot bolt is also nickel plated.
Great big beefy collimation and locking screws with nice easy and smooth action! Springs are plenty strong enough to hold the weight of the mirror without sagging. No change in collimation after tightening locking screws. No discernable shift in collimation from 25deg to zenith. A small shift observed going from 25 to 0 degree altitude (locking screws loose or tight makes no diff).
This is what I do with any Newt I buy: Pull the mirror cell out. Undo the mirror clips. Loctite the screws (so they don't fall out in transit) and put the clips back in very loose so they apply no pressure to the mirror. Well guess what? That is already done on the Saxon! There is about 0.5mm clearance between the mirror and the clips, and the screws are loctited in place. I could rotate the mirror in its cell which is how it should be. There are six clips, which IMO is an overkill, so I removed three. There was no markings on the mirror under the clips I've removed.
The primary mirror looks immaculate. No chips in the sidewalls like on both my GSOs (not that this would affect the views but still it's nice :)) The mirror I'm told is made of pyrex glass, and made in the US (the scope itself is made in China). I would not know how to tell pyrex from the rest, but the glass looks clear, while my other scopes have glass that has a greenish tint.
Centre spot precisely placed in centre, to the nearest 0.5mm I could measure.
No plastic housing for secondary means the central obstruction is just the mirror and nothing else. Central obstruction measured at 50-51mm. Aperture measured at 255-256mm => Central obstruction no greater than 20% (compare with 25% for GSO Dobs).
The secondary is glued in place on a smaller holder behind it, so there is no mirror clip and no retaining screw in the light path. All screws affixing spider to mirror holder are also well behind the secondary, making for a nice clean circular central obstruction.
Eyepiece holder on front of the base not on the side, so no more worrying about kicking my EPs or smokers looking through my scope inadvertantly using my Pentaxes as ashtrays.
Heads of screws for holding mirror cell and "spider cell" (?) to ends of OTA are sufficiently large to properly cover the holes in the OTA. This is not the case for GSO Dobs (incl. Lightbridges I've looked at) where the screws heads are barely larger than the holes. It might not seem like a big deal but what I am consistently seeing in this scope is attention to detail. Good!
Instructions are good. I haven't read them extensively because the pictures tell the story well, but when I needed to refer to them I found what I was after. All tools are included, including philips head screwdriver, allen keys and two spanners. The screwriver was a little undersized for the screws for the feet though (can make do but better get a beefier one for these).
The finish of the components is very good. The base is high density chipboard, but it is very well laminated. There is no bare chipboard exposed anywhere on any surface or edge, and the laminate/edging is well and truly stuck onto the boards.
Paint looks good, and tougher than the coat of silver-grey on most of the GSOs. But I already knew that. ;)
The two silver top plossls: 10 and 25mm. Good starter pair. I have used this type of EP before and they are quite nice. They hold up well against top brand plossls.
The scope can be picked up and carried as a whole unit by the tensioner handles. Not as easily as the 8" but still quite grab-n-goable.
The not so good and the the indifferent:
Rack and pinion focuser and it does have a bit of backlash. It has a larger footprint than a GSO focuser, so the GSO crayfords will not bolt on. I am not sure if there is even enough room around the hole in the OTA to drill holes for fitting the GSO focuser. You can buy ED80 style Crayfords from Saxon that bolt straight onto the bracket, but I would prefer the GSO with the 10:1 geared fine focuser.
Secondary collimation needs allen key.
No bump cushioner for OTA at zenith. My first mod: a bit of felt on the base.
Altitude bearings are "sticky". They squeak and creak before they get moving smoothly. Mick Pinner recommended a bit of graphite. Going to try that tomorrow. I will also consult with John Izzo and Daniel(sun) to see if they have any tips. Teflon might be the go (the big bearings are nylon).
Focal length is just 1200mm. With an aperture of about 255mm, this makes the scope an f/4.7, which means it will be extra fussy with eyepieces. The OTA is nice and compact though and I already have EPs that will work fine at f/4.7, so I don't mind.
The OTA sits quite high in the base. You can see it in one of the photos next to the GSO 8". There is heaps of room underneath. I'd prefer if it sat closer to the ground, which would make the whole setup more stable and seated observing near zenith easier. I might just have to do something about that too... :confuse3:
Oh, and no ebony star on base board! But who am I kidding, right?
That's about all I have to say about this scope till first light. :)