Marc1964

3 hours ago, wibblefish said:

I think a simpler system like this would be more useful!

Hmmmm... youve been hanging around with @Tiny Clanger too long....

2 hours ago, reezeh said:

If you're ever planning on H-alpha solar I can't see any disadvantage at all. CA should not be an issue, saving you a lot of money over an apo. And aside from imaging an achromat isn't a big handicap. Go back not a million years and achromatic refractors were seen as serious kit well worth having. A six inch achro was "THE Mars scope to have"

A good telescope is anything you're using and looking through. If it shows you things, then it's a good scope. 

 

Edit: Additional: talking of solar,  even white light and projection is something suitable for an 80mm achro. The just above 1" resolution is getting close to what you'll achieve in daytime most places anyway.  And chances are, the objective lens won't suffer as a cemented apo. Just get some cheap uncemented eyepieces if you want to project the sun. 

it's a  win-win! 

Not planning solar - not something that interests me at all at the moment!

56 minutes ago, Macavity said:

I *think* the idea is to THINK about performance (your experience) of scopes
in areas you try them out. My first ever scopes were a MAK90 and an ST102...
Deliberately "chalk and cheese"? Taught me a lot? Form your own opinion?

Despite "Swearers by" certain scope types, their is also some commonality.
Quality, aperture and focal length seem to matter as much as scope type? 🙂

Completely agree.  Compromises, or trade-offs are always needed - however what I need has to be portable - I have no good seeing conditions from my garden, so either have to drive somewhere or walk for 15 minutes to a set of fields.  Portability is therefore a must - as important as all the factors you correctly identify!

I have, and love my current refractor.  I have looked through dobsons and appreciate the light gathering abilities.  Not loooked through a Mak yet - that will have to wait, so that is next year's plan 🙂

Horses for courses and I'm in this for the long term, no need to rush - which is just as well given the general lack of stock!

2 hours ago, Tiny Clanger said:

My eyes  saw 'starhopper' , for some reason my brain said 'spacehopper' and I thought, that's not going to keep a newt collimated ! 🙂

It will be the Hubble mirror disaster all over again!

11 minutes ago, KP82 said:

When I bought it I also thought the ED glass (the exact specs weren't disclosed) would help with surpressing the CA. But in actual use, the ED was pretty much non-existent.

This is what I was concerned about. Unfortunately full ED or APO set up is beyond my budget. I was leaning towards the 102/600 anyway as I am concerned that the extra cost of the 102xs is worth it... 

7 minutes ago, wibblefish said:

I am trying not to get hung up on chasing new telescopes already!

Very sensible! I have had my 90/910 for two year now and bought it with an AZ3 mount for the princely sum of £60. I wanted to be sure that it would be used, and it has. I therefore feel OK about looking at alternatives/addition... 😁 

24 minutes ago, wibblefish said:

have a refractor atm, 90/66

Yes, I read somewhere in the forum that you had a Skywatcher I believe? I am thinking of the Bresser Messier AR-102S/600 version which supposedly has better build quality... However am also tempted by the AR-102S/460 which has an element of ED glass which is supposed to help with reducing CA to the equivalent of an F7 scope. Also tempted as I said above by a Long Pern but buying from EU and not understanding exactly how much custom charges are is putting me off somewhat! 

7 hours ago, Tiny Clanger said:

Who, me ? Surely not ! 😇

I'd not want to carry the heritage 150 dob very far either : it's not particularly heavy, but it is a bit unwieldy. I've never seen a heritage 130 in person, so couldn't comment on how easy one of those would be to carry for 15 min.s.  Had you thought of a wheelbarrow or the sort of small hand truck people buy for carting camping or fishing kit around ? Or a child's buggy ! Wrap a heritage dob in a blanket and take it for a walk ...

Sanity is overrated in my opinion .

@Tiny Clanger Are you a founding member of the 'Dobsonian Telescope Liberation Front' perchance?

I actually did look into a small trolley of some sort but TBH didn't see anything that would carry the Bresser Messier 6" table top mount or the planetary securely without shaking. That would be bad for the scope and the idea of nightly collimation.... I know Bresser do a handle which is useful, but again it's either the base or finding a good support which is key.

I like the lovely contrasty image that a refractor gives and whilst I am well aware that for the price of a decent small refractor I could have a damn good dobson, the best telescope is the one you use the most, and I know, sadly, that no matter how good a small dobson is, I would use a small refractor more. 

This year the refractor. Next year a Mak 127.... 😁 

It's a good thing that there are virtually no relatively inexpensive 'scopes to be had in the UK because I reckon I would have bought at least two.. 😁 

I have an Evostar 90/910 on an az3 with two cheap Celestron Omni plossl lenses. I've really enjoyed the viewing and it's ability to get the orion nebula, split Rigel and a few other stars etc. It is however big and bulky to carry around and I know there have been times when I have not gone out because I can't face the 15 minutes of walking with my gear to the darker fields to view. 

A smaller refractor, a 90/500 would be perfect but hard to find. Teleskop Express have an interesting black Long Perng in stock, but I am hesitant to pull the trigger as customs costs are unclear right now.

I thought about getting a dobson (Tiny Clanger malign influence) and spent a long time thinking how I could make a 5" or 6" short dobson work with needing to be carried. Needless to say sanity has prevailed and this is off the list. 

I have considered a 90, 100, 127 mak but been put off by narrow field of view. I want to star hop my way round the sky and learn about what is above me... 

I have nearly bought at least one of these and only one of them really meets my needs at the moment, and is the right tool for the job. I want a wider FoV than the 90/910 and want light and compact. The short refractor wins at the moment , but I have no doubt that the others will appear at some stage when I decide I want something different or I get fed up and impulse buy a dobson and curse myself whenever I have to transport the thing either by car or walking... 😁 😁 😁 

On 03/11/2020 at 09:00, Stu1smartcookie said:

I am particularly heartened to read that ! It gives me hope that i actually can achieve a 6 scope haul lol

Hi @Stu1smartcookie

I've just spotted this post and wondered if you bought either of the 90/500 achromats you were looking at? The Omegon is currently on sale at £230 which seems to be a decent price, cheaper than the Svbony. Read a couple of dubious things about the Svbony ebay store so not keen to go down that route. I'm also waiting to see when the Bresser AR-102 S comes back into stick anywhere.  

Cloud. Cold. Garden is a bog. Considering hibernation. 

Managed to get the scope out quickly at 1820. Original forecast was cloud cover, so caught by surprise 😁. Had a really nice view of Mars, best that I had seen for a few weeks. Went for the Pleiades and the cloud cover rolled in.😒. Total viewing time approximately 30 minutes.

49 minutes ago, KP82 said:

The Bresser 6" dob is an f/8 scope with 1200mm focal length instead of 750mm found on the SW heritage 150. This translates to easier collimation, smaller central obstruction (higher contrast) and being much more forgiveable on eyepieces.

The focuser is also a notch above the SW. The tube ring will allow the scope to be attached to a different mount much more easily than any SW dobs. If you've made up your mind about a newt on a dob base, go for it. To get quality views with a refractor, you really need to spend a lot more than this.

There are two models: the one you describe is the 'planetary' dobson, there is a table top mount 6" dobson which is 750mm and therefore fits nicely in my car boot... 

No final decision made yet, no stock in UK so no rush. I'm still thinking that a refractor may be a better option (102/600) in terms of my starting point which was a grab and go scope which I could move around easily with etc. but I would need a new mount.

Certainly get more bang for the buck with a dobson... 

2 minutes ago, Tiny Clanger said:

I've not seen that one before, or read any reviews. On one hand it is £90 more than the 150 heritage, and does not close up to half length for easy transport & storage,  but on the other , its focuser may be less agricultural than that of the Heritage ,and it comes with tube rings .  Otherwise the important bit of the 'scopes is the same: 150mm diameter , 750mm focal length

Bresser 'scopes (apparently, I have no experience of them myself) are usually rated as better built than skywatcher, so I guess it depends if you think the price difference is worth it.

The focuser alone seems to be a decent upgrade, and the lenses it comes with are apparently surprisingly decent... Not as portable, but seems to be a decent trade off build quality and portability... 😁 Just need to figure out what to put it on when I am out and about! 

On 30/12/2020 at 13:37, Tiny Clanger said:

What I failed to completely grasp before actually buying and using a 'proper' telescope is that some of the accessories are just there as a 'get you started' measure, I liken them to those special, low capacity ink tanks some inkjet printer manufacturers supply with new printers . Enough to prove the thing works, but you will soon be spending some more money ...

Every skywatcher 'scope I've looked at seems to come with the same 10 and 25mm eyepieces, the 10mm is horrible, the 25mm is OK The cheapest upgrades would be standard plossls ( around £20-£30 each) which are a small but noticeable step up , but the current favourite recommended 'cheap' eyepieces are BST Starguiders, which are at the moment close to £50 each including P&P.

Ditto the finder on most scopes is a very basic model, I put up with the RDF  for a few months, but performing contortions to get my eye in line , and problems with averted vision visible objects being impossible to see looking straight at via the RDF sent me buying a RACI ...

Then on my shiny new mak I can use the RACI, but ... there is only one finder shoe, and an RDF would be useful for some brighter objects, and I'm too cowardly to dismantle it to drill holes for a second shoe ... So I end up buying a rigel quickfinder which has a small footprint, stick-on base .

So, I've spent around £80 in total on better finders (which can be swapped between the two 'scopes ) and at least double that on eyepieces. Nearly forgot, there's the original kit diagonal on the mak, it was plasticky and not very lovely. I got lucky and bought a second hand skywatcher dielectric star diagonal second hand from a seller on here , new it would have been £69.

@Tiny Clanger you have put doubt in my mind. I have disappeared down the refractor vs reflector debate and agonised over dobsonian mounts... So I am now contemplating this: https://www.harrisontelescopes.co.uk/acatalog/bresser-messier-6-dobsonian.html#SID=1739

Hi, I was wondering if anyone else had got there hands on one of these and has anything to share about the scope being used in action for viewing? Not fussed about the imaging side, purely interested in the observing side at the moment... 

Just now, vlaiv said:

Each surface where two mediums with different refractive index meet is degree of freedom for optical designer.

With air (or oil) spaced doublet you really have 4 such surfaces:

First lens has air/glass and then glass / air surface (or glass / oil) and second lens has again air/glass (or oil/glass) and then glass/air surface. Each of these 4 surfaces (first lens front and back, second lens front and back) can have different curve to it and combination of these curves (and distance between them) defines optical properties of system.

With cemented doublet - you only have 3 surfaces - you have air / glass1, then glass1/glass2 and finally glass2/air (as glasses are touching - they must have the same curve where they meet).

Less surfaces to work with and less things you can tweak for optimum optical performance.

Thank you - my education in telescope technology continues....

3 minutes ago, vlaiv said:

Real thing - type of lens, you can have air spaced, oil spaced or cemented doublet (probably even other kinds depending on material used between lens).

Air has refractive index that needs to be matched to glass when designing optical characteristics.

Air spaced is usually better than cemented (more surfaces that can be independently curved) and is light enough as construction does not require additional weight.

So an 'air spaced' doublet should in theory be optically better I assume than a cemented or oil doublet?  Or is the answer 'it depends'?

OK quick, probably dumb (!) question:  Is an 'air spaced' doublet a thing or just marketing speak?

15 hours ago, Nyctimene said:

The Heritage 130 P Flextube in the trunk of my tiny Seat Mii,

together with a folding stool and the PSA in the left corner. Still enough space for some eyepieces...

Stephan

Your Mii has a nice deep boot which ironically is better than the Mini boot... 😁 

Seriously though, was good to see a picture with the scope in! Thanks! 

4 hours ago, Tiny Clanger said:

What I failed to completely grasp before actually buying and using a 'proper' telescope is that some of the accessories are just there as a 'get you started' measure, I liken them to those special, low capacity ink tanks some inkjet printer manufacturers supply with new printers . Enough to prove the thing works, but you will soon be spending some more money ...

Every skywatcher 'scope I've looked at seems to come with the same 10 and 25mm eyepieces, the 10mm is horrible, the 25mm is OK The cheapest upgrades would be standard plossls ( around £20-£30 each) which are a small but noticeable step up , but the current favourite recommended 'cheap' eyepieces are BST Starguiders, which are at the moment close to £50 each including P&P.

Ditto the finder on most scopes is a very basic model, I put up with the RDF  for a few months, but performing contortions to get my eye in line , and problems with averted vision visible objects being impossible to see looking straight at via the RDF sent me buying a RACI ...

Then on my shiny new mak I can use the RACI, but ... there is only one finder shoe, and an RDF would be useful for some brighter objects, and I'm too cowardly to dismantle it to drill holes for a second shoe ... So I end up buying a rigel quickfinder which has a small footprint, stick-on base .

So, I've spent around £80 in total on better finders (which can be swapped between the two 'scopes ) and at least double that on eyepieces. Nearly forgot, there's the original kit diagonal on the mak, it was plasticky and not very lovely. I got lucky and bought a second hand skywatcher dielectric star diagonal second hand from a seller on here , new it would have been £69.

Hi, yes I have come to realise this... I quickly bought two new Celestron omni plossl lenses (15mm & 32mm)off ebay for around £40 new total. I have no idea how they compare to other brands but a major improvement on the SW ones that came with the scope... Need to replace the Barlow next, and then the diagonal.... 

I was out for a walk on the South Downs this afternoon and about 10 minutes walk from my car park where I do majority of my viewing, there is a concrete water tank about table height. Could be used for a mini dobson... Maybe the Orion Starburst 4.5 or the SW Heritage could come into my life... 

Scouring ebay and used sites to see what the art of the possible is now! 

4 minutes ago, johninderby said:

Pretty much what I found with the Bresser 102xs.

Doesn't sound like a good long term scope. I wonder if the larger AR-102S is better in this regard? More reading to be done... 

14 minutes ago, vlaiv said:

Check this out:

http://interferometrie.blogspot.com/2017/06/3-short-achromats-bresser-ar102xs.html

OK thanks. Very technical review! So if I follow this correctly, the CA on the AR 102 xs is poor compared to the known ED glass of competitors, therefore the claims of using an ED type glass should be taken with a pinch of salt... This could be a good reason not to consider the shorter Bresser then... 

10 hours ago, Davesellars said:

Ah, that's a shame.....  Get a bigger car????

I used to walk with gear from my apartment about 15 mins walk to an allotment where at least I kept my mount in a shed.  I can relate to the need to keep it lightweight though!  TBH, the mount is the most problematic to find something sturdy enough (especially for planetary obsevation) that you can physically walk with the any length of time so perhaps stick with using the car.    If the tripod at least goes in without having to lay down the seats you may have more options?

Yes the mount will be the biggest issue. They are not cheap and cheap ones are probably not very good! 😁 John gave a recommendation for me for an AZ5 mount and legs which I will probably follow... 

Actually the biggest problem is the 900mm tube in the mini, the mount less so! The mini boot and the width of the car mitigates against a 900 tube. A bigger car is probably on the cards in the next 12 months but for reasons other than astronomy (shockingly enough!). 

19 hours ago, johninderby said:

90mm isn’t a common size for ED or APOs and hence seem to be a bit expensive.

There are some fine triplet 90mm APOs but £££

https://www.teleskop-express.de/shop/product_info.php/info/p5964_TS-Optics-CF-APO-90-mm-f-6-FPL55-Triplet-with-Certificate.html

Ouch!