Jump to content

SkySurveyBanner.jpg.21855908fce40597655603b6c9af720d.jpg

Revelation 12" Dobsonian

arad85

By arad85
in Member Equipment Reviews

Recommended Posts

AlanK

AlanK

Posted
Posted

Hi Tony.

In spite of the condition of the mirror I still feel that it is providing good images, but how can you judge?. May get it recoated later in the year but it will do for now.

Light pollution not too bad over here, but again it depends where you are in relation to streetlights, same as anywhere else. But at least you do not have to travel too far to find somewhere dark. The last few nights have been great, but the light easterly wind is beginning to build up 'murk' from the adjacent Isle (UK) along the horizon. NW breeze is better to blow it back where it came from:)

Link to comment
Share on other sites
  • Replies 125
  • Created
  • Last Reply
  • 1 month later...
OneSG

OneSG

Posted
Posted
TH are the revelation importers and only available through them as far as I know. Perhaps give them a ring and see when they may be having more in stock...

Thanks for the info chum. I e:mailed Telescope House and was told that they last had the Revelation 12" in stock about four years ago. If they are the sole stockist it looks as if that scope is no longer available.

Link to comment
Share on other sites
nightvision

nightvision

Posted
Posted
I have searched the net and cannot find anyone who stocks these scopes. Even Telescope House does not seem to have these in stock now. Does anyone know of a UK stockist?

They do come up on for sale on this forum and AB&S, there were a couple of nice examples (with upgrades) just recently.

I noticed the Rev version aren't around these days however I beleive the Meade and Skywatcher dobs are made at the same factory.

The Rev 12" did average in the early reviews but this turned out be due to the substandard collimation bolts on the primary and the need for plenty of cooling (BK7 glass primary). It also provides better views with the fan off.

This is a good review of the latest version to come out of Synta, its the Skywatcher model using the same optics:

http://www.opticalvision.co.uk/documents/80.pdf

Available at most places in the UK;

Dobsonians

Skywatcher Dobsonian telescopes

Somone in Portugal even put one on a NE6 mount and did some imaging!

http://stargazerslounge.com/imaging-deep-sky/140362-m-101-12-gso-newt.html

:D

Link to comment
Share on other sites
johninderby

johninderby

Posted
Posted

Meade dobs are made by GSO and SkyWatcher dobs by Synta so they do not have the same optics although they are of similar quality.

John

BTW the same scope is still available form Telescope Service.

http://www.teleskop-express.de/shop/product_info.php/info/p1190_GSO-Dobson-980---12----300-1500mm-Teleskop---Deluxe-Version.html

Link to comment
Share on other sites
arad85

arad85

Posted
  • Author
Posted
Thanks for the info chum. I e:mailed Telescope House and was told that they last had the Revelation 12" in stock about four years ago.
Amazing, given I bought mine from them in 2009 and they were in stock for a good 6 months+ after that....
Link to comment
Share on other sites
  • 1 month later...
derekm

derekm

Posted
Posted

Maybe this coating issue concerns only an odd bad batch that got overlooked.

Even adding the cost of a recoat (should it be required) after 2 or 3 years, you still have very impressive optics for a sensible price

Link to comment
Share on other sites
  • 1 year later...
starpods

starpods

Posted
Posted

Hi everyone, I have an older revelation12 with the plastic bearings, and I need to ask a daft question as I need some measurements from someone who also has one1

Mine is in southern spain which i get to use 3 or 4 times a year, I gave up in high wycombe with too much light and too few nights above freezing and clear enough to seeanything.

I want to make an eq platform so can anyone measure theirs for me so I can get it right?

I need the diameter of the base, height of the centre of rotation of the tube, and the distance of the tube mirror end from the centre of rotation?

Thanks!

Brian

Link to comment
Share on other sites
  • 2 years later...
Mark at Beaufort

Mark at Beaufort

Posted
Posted

Its been a few years since the Revelation 12" Dob has been discussed in any detail. Clearly many threads referred to the mirror coating and the poor springs. Telescope House have had the Revelation scopes in stock for some time and the 16" Truss version was added a few years back.

My question has anyone bought the 12" Revelation in the last couple of years and have you an opinion? I have undertaken a search but this thread seems to contain the most information.

Link to comment
Share on other sites
simmo39

simmo39

Posted
Posted

Its been a few years since the Revelation 12" Dob has been discussed in any detail. Clearly many threads referred to the mirror coating and the poor springs. Telescope House have had the Revelation scopes in stock for some time and the 16" Truss version was added a few years back.

My question has anyone bought the 12" Revelation in the last couple of years and have you an opinion? I have undertaken a search but this thread seems to contain the most information.

Hi, Had my 12" Rev for about 12 months and think its brilliant. I have had no problems with the mirror but did change the springs. I would recomend one to anyone who is capable of moving it as its not that light.

Link to comment
Share on other sites
John

John

Posted
Posted

I hope the coatings issue has been addressed with the current generation of GSO / Revelation dobs. The springs clearly could still be improved. I've never been impressed with the 1/12th wave claim because they deliberately (IMHO) don't specify whether it's PV or RMS. It's the latter if you enquire.

Link to comment
Share on other sites
Mark at Beaufort

Mark at Beaufort

Posted
Posted

Hi, Had my 12" Rev for about 12 months and think its brilliant. I have had no problems with the mirror but did change the springs. I would recomend one to anyone who is capable of moving it as its not that light.

Thanks for that. Did you get your springs from Bobs Knobs?  - http://www.bobsknobs.com/Newt/page45/NewtPri.html

Link to comment
Share on other sites
Mark at Beaufort

Mark at Beaufort

Posted
Posted

I hope the coatings issue has been addressed with the current generation of GSO / Revelation dobs. The springs clearly could still be improved. I've never been impressed with the 1/12th wave claim because they deliberately (IMHO) don't specify whether it's PV or RMS. It's the latter if you enquire.

John I have decided that I really want a 12" scope. I would prefer an Orion UK with 1/6th or 1/8th wave but they are expensive as you know.

The 12" Revelation looks a good scope for the money but there are unanswered questions as you pointed out.

If the 1/12th wave is RMS that could mean that the PV could be below 1/4 wave - I have always understood that the RMS value is approx 3.5 times the PV. If it is 1/12th RMS this is only the bare minimum set against the Rayleigh Limit. I suppose the only real test is the Strehl ratio which requires .82 as being the minimum.

Perhaps I should ask TH for a formal specification of the mirror and secondary.

Link to comment
Share on other sites
faulksy

faulksy

Posted
Posted

John I have decided that I really want a 12" scope. I would prefer an Orion UK with 1/6th or 1/8th wave but they are expensive as you know.

The 12" Revelation looks a good scope for the money but there are unanswered questions as you pointed out.

If the 1/12th wave is RMS that could mean that the PV could be below 1/4 wave - I have always understood that the RMS value is approx 3.5 times the PV. If it is 1/12th RMS this is only the bare minimum set against the Rayleigh Limit. I suppose the only real test is the Strehl ratio which requires .82 as being the minimum.

Perhaps I should ask TH for a formal specification of the mirror and secondary.

this might be just what your looking for mark

http://www.astrobuysell.com/uk/propview.php?view=97010

Link to comment
Share on other sites
John

John

Posted
Posted

John I have decided that I really want a 12" scope. I would prefer an Orion UK with 1/6th or 1/8th wave but they are expensive as you know.

The 12" Revelation looks a good scope for the money but there are unanswered questions as you pointed out.

If the 1/12th wave is RMS that could mean that the PV could be below 1/4 wave - I have always understood that the RMS value is approx 3.5 times the PV. If it is 1/12th RMS this is only the bare minimum set against the Rayleigh Limit. I suppose the only real test is the Strehl ratio which requires .82 as being the minimum.

Perhaps I should ask TH for a formal specification of the mirror and secondary.

I asked TH this question last year. They confirmed that it was an RMS figure. I wish they would state that in the marketing blurb but I guess 1/12th wave sounds a lot better than 1/4 wave just ! :rolleyes2:

Some might exceed this of course. Damo has or had a Revelation 12" dob that performed very well I seem to recall.

Link to comment
Share on other sites

Archived

This topic is now archived and is closed to further replies.

Go to topic listing

  • Recently Browsing   0 members

    • No registered users viewing this page.
×
×
  • Create New...

Important Information

We have placed cookies on your device to help make this website better. You can adjust your cookie settings, otherwise we'll assume you're okay to continue. By using this site, you agree to our Terms of Use.