Jump to content

Welcome to Stargazers Lounge
Register now to gain access to all of our features. Once registered and logged in, you will be able to create topics, post replies to existing threads, give reputation to your fellow members, get your own private messenger, post status updates, manage your profile and so much more. If you already have an account, login here - otherwise create an account for free today!
Photo

Revelation 12" Dobsonian

- - - - -

  • Please log in to reply
114 replies to this topic

#1
arad85

arad85

    Brown Dwarf

  • Advanced Members
  • 2,079 posts
  • Location: Wiltshire
OK, so this is the first post in a series where I'll review the 12" Revelation. This post will deal with the "out of box experience" and I'll add more as I do observing/get more acquainted with the beast.

Building

OK, so to start with, the beast comes in two boxes - the main box containing the OTA and a second flatpack box containing the base. These things are relatively big - the OTA box is about 1.7m long, and weighs 24kg, but still, if you want a big dob, that's what you expect.

Posted Image

Opening the boxes shows the innards. Firstly, the OTA. For something so large, I think it is lightly packed (I had to return one OTA as the plastic packing ties had been used as handles by the couriers and gone through the cardboard and bent the OTA!). In comparison to Celestron - where I've always had things in two cardboard boxes - it is liable to damage in transit.

Posted Image

You can also see the accessories that come with the OTA in situ.

You get:

  • 30mm WA Revelation eyepiece
  • 9mm Revelation plossl
  • 35mm extension tube (needed to reach focus on some eyepieces)
  • 8x50 finderscope and bracket
  • battery cage for the fan in the base

These are shown here:

Posted Image

The mount box contains the mount, all the screws as well as the accessory tray as well as some instructions on how to assemble from Telescope House. The instructions were adequate, but they were for an older version of the mount as there were some minor discrepancies between my mount build and that in the instructions.

Posted Image

With a little careful thought (figuring out which weay is the bottom on the baseplate - it's actually with the screw insert at the bottom, I fixed the 3 stubby legs and had the whole mount built in about 20 minutes. Build quality is OK, but then this isn't a premium mount and it does rather look like it is from the Ikea Darth Vader collection.

Posted Image

Still, it is functional. One point to note is to ensure you get the sides the right way around. You have when the felt on the rear of the cutout where the tensioners fit is towards the back of the box.

OK, so that's the box built. Now to the OTA. The OTA uses some hefty machined knobs to mount into the rocker box. These are attached to the side of the tube via allen bolts in a nifty sliding holder that allows you to alter the rotational point of the tube. Put the knobs higher, the tube becomes base heavy, lower and it becomes top heavy. Quite neat I thought (although I don't have any knowledge of the Skywatcher or Meade fittings which look different. Unfortunately, as these are fixed with allen bolts, you can't change the balance in the field to counteract different weight EPs. This is where the knobs fit:

Posted Image

and here is an image of them fitted:

Posted Image

What you can alter is the tension in the pivot. Screwing the two knurled knobs up increases the turning resistance, unscrewing them decreases the resistance.

Here is a picture of the competed tube on the mount.

Posted Image.

Tube detail
I must say, that for the price, I'm very happy with the details of this OTA. Firstly, the round circle appeared centrally placed to as near as I could measure it and the mirror mount looks sturdy and has a fan to cool it. Additionally, the collimation/locking knobs seem of good quality (although I have been advised I may need to change the springs for some from Bobs Knobs (see: MLB12).

Here is a picture of the underside of the mirror showing both the knobs, 9 point mounting and fan:

Posted Image

Another thing I am impressed with is the focuser. It is a dual speed Revelation and appears to be very smooth. Although I don't have any experience of the more expensive after-market crayfords, this one is an order of magnitude smoother than the rack and pinion one attached to my C80.

Posted Image

That's it for now - as soon as I get it out on a night, I'll compare it alongside my C9.25 and post back some initial impressions. Bear in mind that this is not only my first review, but also the first proper view through a Newtonian (although I have another, it is in use by someone else and I've never looked through it ).
'Scopes: Umm.. none
EPs: Celestron X-cel 25mm (but no 'scopes)
Cameras: Canon 5Dmk2, 450D, EF-S 18-55 IS, EF 24-105 F4 L, EF 50 1.8, EF 70-200 F4 L

#2
Doc

Doc

    Sub Giant

  • Advanced Members
  • Pip
  • 9,655 posts
  • Location: Nottingham
A very detailed and entertaining read.

One thing I'm surprised about is how small the altitude bearings are. I thought the Meade LB ones were small but these are smaller.

The OTA looks very nice indeed. Looks a perfect size for the base and looks extremely well proportioned.

What's the azimuth bearing like? Is it a lazy susan type.
Mick

Bresser Messier R152s Achro.
WO GT-81
HEQ5 Pro + EqTooth
Full set of WO Uwans

Messier objects - 93/110
Herschel objects - 151/400
Caldwell list - 36/67 - limit in UK
Hidden Treasurers - 40/88 - limit in UK
Lunar 100 - 100/100 Finished
Lunar 100-200 - 53/100
Supernovae - Three
Planets seen - Six

#3
arad85

arad85

    Brown Dwarf

  • Advanced Members
  • 2,079 posts
  • Location: Wiltshire

What's the azimuth bearing like? Is it a lazy susan type.

Two metal plates of about 8 inches diameter encapsulating a rollerball (there are about 20 rollerball bearings around the outside of the middle insert) lazy suzan circle. You tension it by screwing down on the knob at the centre of the base. Seems to work very well and is very smooth... :)

As to the altitude bearings, they may be small, but they are quite heavy and appear to be machined. They certainly fit very well into the cutouts. We'll have to wait until I try it in anger to see if the clutch mechanism in them is effective... For some scale, the knurled knobs are 7cm across...

I agree with you - well proportioned, and I quite like the black rocker box...
'Scopes: Umm.. none
EPs: Celestron X-cel 25mm (but no 'scopes)
Cameras: Canon 5Dmk2, 450D, EF-S 18-55 IS, EF 24-105 F4 L, EF 50 1.8, EF 70-200 F4 L

#4
Doc

Doc

    Sub Giant

  • Advanced Members
  • Pip
  • 9,655 posts
  • Location: Nottingham
Same set up as my Meade azimuth bearing.

7cm across the picures don't do the size justice.
Mick

Bresser Messier R152s Achro.
WO GT-81
HEQ5 Pro + EqTooth
Full set of WO Uwans

Messier objects - 93/110
Herschel objects - 151/400
Caldwell list - 36/67 - limit in UK
Hidden Treasurers - 40/88 - limit in UK
Lunar 100 - 100/100 Finished
Lunar 100-200 - 53/100
Supernovae - Three
Planets seen - Six

#5
GazOC

GazOC

    Hyper Giant

  • Advanced Members
  • PipPipPip
  • 17,739 posts
Nice report!! Things have really moved on since the last time bought a Chinese Dob...:)

#6
arad85

arad85

    Brown Dwarf

  • Advanced Members
  • 2,079 posts
  • Location: Wiltshire
I really am chuffed to bits with this... Quality seems exceptional for the money. They obviously have understood how to make the bits that matter good... Time will tell if the optics are any good (but I was assured it's the SAME mirror that goes into a lightbridge...

Now if only they made a 16" :)
'Scopes: Umm.. none
EPs: Celestron X-cel 25mm (but no 'scopes)
Cameras: Canon 5Dmk2, 450D, EF-S 18-55 IS, EF 24-105 F4 L, EF 50 1.8, EF 70-200 F4 L

#7
nitram100

nitram100

    Proto Star

  • Advanced Members
  • 699 posts
  • Location: Harrow, London
A 9 point mirror cell, fan and a dual speed crayford is awesome!

Look forward to the first light mate, good luck.
Orion Optics 10" F4.8
NEQ6 Pro
Celestron 15x70 Skymasters

#8
Talyn

Talyn

    Star Forming

  • Members
  • 200 posts
Looks good, Arad. 24kg OTA? Not as heavy as I thought it would be - about the same weight as my rucksack when I went off travelling earlier this year!

#9
arad85

arad85

    Brown Dwarf

  • Advanced Members
  • 2,079 posts
  • Location: Wiltshire
For those that have asked about the azimuth bearing... here is a picture of it:

Posted Image
'Scopes: Umm.. none
EPs: Celestron X-cel 25mm (but no 'scopes)
Cameras: Canon 5Dmk2, 450D, EF-S 18-55 IS, EF 24-105 F4 L, EF 50 1.8, EF 70-200 F4 L

#10
haitch

haitch

    Sub Dwarf

  • Advanced Members
  • 1,896 posts
  • Location: Brownhills, West Midlands

Looks good, Arad. 24kg OTA? Not as heavy as I thought it would be - about the same weight as my rucksack when I went off travelling earlier this year!


Ideal for when hiking to dark sky site then!!!:)

Nice to see the bearing setup on some less "agricultural" dobs than my Darkstar. I really must sort out the altitude bearing on mine for something neater (my wife is rather averse to the yellow slices of gas pipe stuck on the sides - you try telling her it's for looking through not looking at!) and tensionable (now I've attached a 2" focuser it just won't stay put when changing EPS).

Nice scope by the look of it - If I were you I'd do something about sealing the joints on the base, it looks like moisture could get in there.
Scopes:- 14" f4.5 Darkstar Dob, [/i]Celestron C8 , C100ED-R, a William Optics Megrez 72[/i]FD and a Celestron C102 f6.5 Achro.
Mounts:- EQ6 with dual axis drives, Vixen GP with LXD75 goto motors, an LXD75 de-gotoed with Vixen MT1 dual axis motors a Celestron SLT goto, Astrotrac on a Manfrotto geared head and tripod, WO Photo/Video Tripod.
Cameras:- Canon 600D & 1000D and a QHY5v
EPs:- ES82 30mm, Nagler T2 20mm, Nagler T2 12mm, Celestron Axiom LX 10mm, Nagler T1 7mm, Vixen LV 5mm
& No time to use any of it!

#11
arad85

arad85

    Brown Dwarf

  • Advanced Members
  • 2,079 posts
  • Location: Wiltshire

Nice scope by the look of it - If I were you I'd do something about sealing the joints on the base, it looks like moisture could get in there.

Good idea - will get the sealant gun out... :)
'Scopes: Umm.. none
EPs: Celestron X-cel 25mm (but no 'scopes)
Cameras: Canon 5Dmk2, 450D, EF-S 18-55 IS, EF 24-105 F4 L, EF 50 1.8, EF 70-200 F4 L

#12
albedo0.39

albedo0.39

    Sub Dwarf

  • Advanced Members
  • 1,376 posts
  • Location: Cheltenham
Looks a brilliant scope and congratulations ! Did they centre spot the primary mirror for you ? I don't recall where I heard it, but I recall that it might be worth checking the position for the centre dot (i.e. that it really is central) because if not, then from that moment on, all your collimation will be out.

As I'm sure you appreciate, it's a fast system so you'll need to get accurate collimation to get the very best out of it.

Also, like the way the ALT bearings are adjustable - seems to be a very simple way to manage the balance of the system without weights.

Looking forward to first light and other info...

Steve
Steve

Cheltenham, UK
16" f4.5 dobsonian reflector

#13
arad85

arad85

    Brown Dwarf

  • Advanced Members
  • 2,079 posts
  • Location: Wiltshire

Did they centre spot the primary mirror for you ?

Yup.. to within the limits of my steel rule and measuring accuracy - it was spot ( :) ) on :)
'Scopes: Umm.. none
EPs: Celestron X-cel 25mm (but no 'scopes)
Cameras: Canon 5Dmk2, 450D, EF-S 18-55 IS, EF 24-105 F4 L, EF 50 1.8, EF 70-200 F4 L

#14
haitch

haitch

    Sub Dwarf

  • Advanced Members
  • 1,896 posts
  • Location: Brownhills, West Midlands

I don't recall where I heard it, but I recall that it might be worth checking the position for the centre dot (i.e. that it really is central) because if not, then from that moment on, all your collimation will be out.
Steve



I read that thread it was about Meade LBs apparently some are so inaccurately placed they must have been thrown on the mirror from several yards away.

A simple thing that could be very frustrating if not accurate and unnoticed so worth checking on any brand.
Scopes:- 14" f4.5 Darkstar Dob, [/i]Celestron C8 , C100ED-R, a William Optics Megrez 72[/i]FD and a Celestron C102 f6.5 Achro.
Mounts:- EQ6 with dual axis drives, Vixen GP with LXD75 goto motors, an LXD75 de-gotoed with Vixen MT1 dual axis motors a Celestron SLT goto, Astrotrac on a Manfrotto geared head and tripod, WO Photo/Video Tripod.
Cameras:- Canon 600D & 1000D and a QHY5v
EPs:- ES82 30mm, Nagler T2 20mm, Nagler T2 12mm, Celestron Axiom LX 10mm, Nagler T1 7mm, Vixen LV 5mm
& No time to use any of it!

#15
Coco

Coco

    White Dwarf

  • Advanced Members
  • 3,833 posts
  • Location: Preston, Lancashire,England
Great write up...

Me want one now .. ooh Xmas seams such a long way...

My 9 yr old daughters B'day's end of August... wonder if she'd like one :)


Guy.....

Clear skies
Guy

BELT DRIVE NEQ6 | Skywatcher Quattro 8s | 314L | 5D3 | 400/5.6 L | 200/2.8 L | EQMOD | SMALL OBS


#16
alfingido

alfingido

    Proto Star

  • Advanced Members
  • 564 posts
  • Location: Whitstable Kent
I've just been to Telescopehouse in Kent and had a look at one of these. I must say i was impressed with the smoothness of movement in both directions. The OTA is not too heavy to lift off the base either, and of course it comes with that ultra smooth focuser. I am still in two minds as to which one I buy between the Skywatcher flexiwotsit 300p and the Revelation as they didnt have the Skywatcher on display.

Look forward to hearing of its first light outing........

Allan

#17
yeti monster

yeti monster

    White Dwarf

  • Advanced Members
  • 3,988 posts
  • Location: UK & China
Serious scope envy brewing here! Nice purchase.
Ask not what your god can do for you, ask instead, what can you do for yourself.

North West Englandshire, near some other forumeers but far away from others. Also rather close to an astronomy centre. Occasionally in the South China sea too.

An entire forest of telescopes, whopping HUGE 20x80 binos, a veritable plethora of EPs, collimators, star charts and wild ideas. And a HUGE, mean, evil and downright bad tempered dawg. :rolleyes:

#18
davo

davo

    Star Forming

  • Advanced Members
  • 296 posts
I bought a secondhand one of these and i still luv it!!!. Absolutely awesome!!!!! There is a post i wrote on here somewhere under the observing reports.

#19
arad85

arad85

    Brown Dwarf

  • Advanced Members
  • 2,079 posts
  • Location: Wiltshire
OK.. On the advice of Steve from FLO, I ordered some primary springs for this scope. In the following two pictures you see the spring that comes with the scope on the left, Bobs spring on the right. Cost £10.60 for 3 springs delivered. CLEARLY a much heavier duty spring that should help hold collimation - once I've got it back again :)

Posted Image

Posted Image
'Scopes: Umm.. none
EPs: Celestron X-cel 25mm (but no 'scopes)
Cameras: Canon 5Dmk2, 450D, EF-S 18-55 IS, EF 24-105 F4 L, EF 50 1.8, EF 70-200 F4 L

#20
arad85

arad85

    Brown Dwarf

  • Advanced Members
  • 2,079 posts
  • Location: Wiltshire
PS. I still haven't had a serious first light with this yet. When I do, I'll post a review vs the C9.25 using the same eyepieces.
'Scopes: Umm.. none
EPs: Celestron X-cel 25mm (but no 'scopes)
Cameras: Canon 5Dmk2, 450D, EF-S 18-55 IS, EF 24-105 F4 L, EF 50 1.8, EF 70-200 F4 L




0 user(s) are reading this topic

0 members, 0 guests, 0 anonymous users