NGC 1502

Interesting comparison 👍……..as you say, a rarely used focal length. I occasionally use my Vixen LV 2.5mm on tight double stars in rare stable atmosphere.  I love seeing the airy disc and diffraction rings, and of course it’s a delight when you finally split that double or triple after many tries!!

Hi Alan, please see incoming email.

Cheers, Ed.

In damp cold conditions your best plan is to put measures in place before dew forms on the optics, not after.

You could make a dew shield from camping mat foam. Don’t make it too short, at least 2x the aperture. Secure with velcro. Perhaps a low heat dew band around the tube, level with the front corrector plate.  If (or rather when) dew does form use a 12v dew gun very carefully.  Check what’s available from our sponsors, First Light Optics.

Don’t be tempted to wipe dew from optical surfaces, especially outside in the dark, it’s so very easy to cause scratches.

Maybe do an online search, see what others have done.

Good luck!

Edit-  click on the FLO banner at the top.  Do a search “dew prevention” lots of equipment available!

Plus 1 for BST Starguiders, great value.  If it were me, I’d go that route rather than a barlow.

3 hours ago, Carl Au said:OO customer service is legendary, and not in a good way. Optically no better than Skywatcher and they don’t hold their value very well either. They are light however and importantly white, black is a stupid colour to paint a telescope 

Very sadly the first part of the above is “sometimes” true but not always.  Different folk can have a different quality of service.  Agreed Asian mass produced mirrors can be excellent.  Premium mirrors need rare stable atmosphere to see the difference.  Many take the view that an Asian mirror is as good as is needed….most of the time. Not so sure that white is the best tube colour. If there’s stray light around the area near the focuser can be distractingly bright.

As always….YMMV 😊

Ed.

9 hours ago, fwm891 said:

 

Interested by the @NGC 1502 comment on the 3" foam on the car's abck seat when travelling. That does seem to indicate how thin the aluminium tube might be? Does anyone know how thin the tube walls are on the VX12?

The reason for using the thick foam:-  My local club runs 2 dark sites.  At one site the final 2 hundred yards is very bumpy and uneven. The other site has a hard road for the last 3 quarters of a mile, but there’s lots of speed bumps.  The foam is not because of thin aluminium tube, just a precaution to avoid messing the collimation.

Agreed that OO does use thin aluminium, but in my experience it’s fully adequate for its purpose.  One advantage with OO optical tubes is they are significantly lighter than the equivalent size from other makes. My club has a 12” Meade Lightbridge for loan.  I’ve borrowed it….the extra light grasp is welcome but the significant weight is not!  A clubmate once owned a 12” f4 from OO UK and it wasn’t much heavier than my 10”, quite manageable in fact.

One way to make a very heavy Dob more user friendly-  When observing from home, if the scope can be stored in a shed or conservatory close to the observing place, 3 lockable castors fitted to the base.

Ed.

I do respect the views of others…..however I have to respectfully disagree with those that say the tube is too flimsy and the secondary spider inadequate to hold collimation.

I own a 10” f4.8 OO UK Dob, and have owned their 8” f6.   I’m not saying they don’t have issues, but holding collimation is not a problem I’ve come across.  In fact the opposite has been my experience.  I’m fussy with collimation, I want each observing session to deliver the best I can get.  
 

I’ve transported my OO 10” many times to both of my local clubs’s dark sites, and to public viewing sessions by car.  The optical tube goes on the back seat of my car with 3” thick foam padding between tube and seat.  The tube is tied to the head restraints for security.  On arrival and after setting up, a collimation check has shown no issues.

Of course the 3 primary mirror clips must not be clamped tight. But neither should they be too slack, that can easily cause the mirror to shift.  Depending on when the scope was manufactured, it’s possible that the 3 collimation springs are inadequate. If those springs can be compressed between fingers, they are woefully too weak. They need to be very stiff indeed to do their job.  The 4 secondary spider nuts that hold the vanes to the tube must not be slack, tightening those cannot clamp the the secondary mirror.

Again, absolutely no disrespect intended😊

Ed.

It’s been a long time I read up about erecting prisms. But my understanding is that the idea is to use an erecting prism with an astronomical refractor.  Such a refractor used without any diagonal (often called straight through viewing) gives an upside down view, so birders for instance won’t want that.  They may be ok with using a regular 90 degree (prism or mirror) diagonal, this does give a “right way up” view, but left and right reversed, and this may be acceptable.  If a “correct view” is required with an astronomical refractor (as seen by our eyes, binoculars, spotting scope) then an erecting diagonal is the answer.

The TeleVue 60 degree diagonal or a 45 degree erecting diagonal gives a “correct view” and at the same time a more comfortable access to the eyepiece for daytime terrestrial viewing.

I tried an erecting prism once for a refractor. My idea was to get a “correct” view, same as you get with binoculars or birding scope.  This gives more intuitive star hopping and navigating the moon’s features.

It works as above.  Decent views at low power, but at medium to high power the sharpness was compromised.

Could be ok for low power terrestrial views.

Possibly the TeleVue 45 degree erecting prism may be better. You could always phone them to ask, they don’t take emails. You will get an honest answer, not sales pitch.

Edit for correction- just checked, the TV erecting prism is 60 degrees.

Ed.

An elasticated shower cap on the back end of the tube should help to keep the critters out. If it’s for a scope larger than 8” then a regular shower cap may not be large enough.   But not too hard for a DIY job to make a larger one….

Definitely agree…..best to clean it.

Late to the party……..

I’m not envious.

I am VERY envious😁

Enjoy….Ed.

22 hours ago, k_martensen said:

Also a sidenote a Dub might not really be an option for me, as the city I live in have decided to place a streetlight pretty much in my garden, so I travel out of the city to a field where I'm allowed to setup in, so there is not really any level place where I can have a dub.

If you intend to travel out of the city how will you get there, by car or public transport?   You only need a small area to set up in, if the field is uneven is there no part of the field you can use?

Also, if traveling by car can you set up close to the car, or would you need to park and carry equipment very far?  How much do you intend to spend, what’s your maximum budget?   If you have a limited budget, best to do visual observing rather than imaging.  Many people new to observing find equatorial mounts confusing!

Perhaps continue to use what you already have for a while, a 3” reflector used with enthusiasm can show you a lot!

The above information will help folks on here give advice.

All the best with your decision 😊

All the best in your endeavours…..however-

Perhaps your enquiry would be better in the “getting started with imaging” section😊

Good online source-google Stellafane telescope making.  Lots of links to further links. Even if you’re not building a scope it’s a great read.

Kriege and Berry book- The Dobsonian Telescope.

Covers everything you need for DIY large Dob build. Includes a section for an 8” solid tube Dob.

5 minutes ago, graham56 said:

still got some naglers in my boxes type1 9mm, type1 7mm  , type 2 20mm, type 4 17mm, type 5 31mm and a 3-6mm zoom

all great eyepieces  the 9mm super sharp

The 7t1 is a little gem, super sharp and small.  I wish I’d kept mine, I now have a 7t6, a bit more eyerelief but I never had problems with the 7t1.  Only Nagler I didn’t get on with was the 4.8t1.   I could cope with the shorter eyerelief, but because my eye was so close to the glass, it was forever fogging up.  Apart from that, it was excellent.

You could try ENS Optical at Birmingham.  They have all sorts of second hand astronomy kit. You may have to buy a complete mount, or you may get lucky and get just the part you need.

Their website says they’re away at the moment. Search the website, or wait until they return and phone. Steve Astbury knows his stuff, I’ve found him helpful in the past.  His prices are high, but his knowledge and service is very good.

If you cannot sort it, the ETX optical tube assemblies can be removed from the mount fairly easily, and fitted to something like a german equatorial mount (GEM) with drive to the RA.  Google “deforking a Meade ETX”.

Another possibility is “Weasners ETX site”.  Don’t know if it’s still online, but if available it’s a source of everything imaginable about all models of the ETX. Keep searching, lots of links to further links.

Hope you sort it.

Ed.

I don’t know if David Hinds is still around to ask, he would be the best source to find out what those numbers mean.

What I do know for certain is those Astrosystems Newtonians were and are top quality scopes, definitely worth restoring.

As a previous owner of the 8.5” f5 version I deeply regret selling.  It gave exceptional planetary and double star views and great deep sky too.

I’ll be following this thread with interest.

Ed.

Ok, having read the above, I’m thinking about selling my Vixen 22mm LVW.

£1000, or very near offer😁😁😁

8 hours ago, Franklin said:

Vixen LVW 22mm, all day long.

I have to agree with that (apart from it’s good at night too😁) incredibly sharp right across the field of view, even in fast scopes.  My fastest scope is a 6” f3.8 Newtonian, and that’s a severe test.

Another severe test is my Edmund Astroscan with its 105mm f4.2 mirror. Unfortunately the 22 LVW is too heavy and the Astroscan tends to dip to the horizon……

With my 10” f4.8 Dob the 22LVW is a corker, the double cluster is a sight to behold….

It would be best if at all possible if you could see your intended purchase at a dealers or a club.  Try it for size and weight. Specifications don’t tell all the story, you might get a bit of a shock when your online purchase is delivered!!

I do realise that may be difficult or impossible according to your location.  An 8” Dob would be safer if buying online. An 8” Dob has to be the best deal going, capable of sustaining a lifetime’s viewing, portable by most folk in reasonable health.

Tring astronomy has a showroom not all that far from you, one of my local clubmates found them very helpful indeed.

Collimation is not the black art some make of it, please don’t let that put you off getting the best value scope in existence.

An excellent upgrade from the stock eyepieces are Starguiders from FLO.  You could buy your 8” Dob from them too, safe in the knowledge that FLO will give top service as well as delivery.

BTW, welcome to SGL👍

As above, for a newbie a Newtonian with an inadequate EQ mount would be a nightmare.  Wobbly and the eyepiece can be in an “interesting” position.

Best buy- a new 8” Dob. Don’t look back, a scope for life. Upgrade the eyepieces for Starguiders, the new price of £55 each is still a great bargain. A new scope has brand new mirror coatings.  The OO Europa is an old scope with crudely mounted secretary, very basic primary cell.

Ed.
 

16 minutes ago, uk_friendly_fire said:

Should I use a 5mm bst starguider eyepiece or Barlow plus 10mm bst starguider in preference?

 

Are starguiders considered cheap?

The choice between a 10mm plus 2x Barlow or a 5mm depends on what other eyepieces you have or intend to get?
In the world of eyepieces the Starguiders are relatively cheap. But don’t let that put you off, I’ve personally tried the 5/8/12mm Starguiders and they’re really excellent value for money, super bargain and a significant upgrade from stock eyepieces that come with many new scopes.

Great to hear that your starhopping is successful 👍

Manually finding objects definitely gets easier the more practice you get. After a while finding previously difficult objects becomes routine.  Then you’ll find yourself finding more difficult stuff, then that too becomes routine……

For those who use a “bells and whistles” scope- please don’t take the above in the wrong way.  The best way to do astronomy is the one that works for you….not what works for me😊

Difficult call……

My main scope is a 10” Dob.  I’m a visual observer of solar system and deep sky.  With deep sky it seems to me that they are not as seeing dependent (steadiness of atmosphere) as the main planets.  For me 150x is often ok with Jupiter and Saturn, that needs an 8mm eyepiece. Globular clusters, smaller planetary nebulae and tight double stars are usually good at 240x, that needs a 5mm eyepiece.  For manually finding objects and viewing large ones I use a 27mm eyepiece for 44x and not too large an exit pupil.  44x to 150x is too large a jump, so I fill the gap with a 14mm for 86x.

So that’s 44x, 86x, 150x, 240x.  That’s what works for me, perhaps not for you!