John

Looking at dob's sw250 sw300 flextube or lightbridge12" couple of questions. Price for the sw250 £450 not bad but is the price jump for the sw300 and light bridge justifiable + £350 -£400. I know they are portable and that's in the price but take that out of the equation can you justify the extra?

The 12" will gather more light, resolve more and show deep sky objects, etc, etc than a 10". Whether that additional performance is worth the extra price to you is a personal decison I guess. The same question could apply to 6" or 8", 8" or 10" and so on. Some say a 2" difference in aperture is hard to notice and some say it's significant to them. If you are primarily interested in viewing faint deep sky objects then any aperture increase is worth having perhaps. Above 12" though the scopes seem to become a lot for one person to handle from a practical point of view.

If you can transport a scope to dark skies then it's performance will jump considerably on the fainter objects so, if that is the plan, getting something transportable rather than the ultimate in aperture, might be important.

I wonder if you were to advertise them on UK Astro Buy & Sell would you have more luck Alan? A lot of members on here don't have access to the classifieds section, so a lot of potential buyers may be missing out on some nice ep's.

Thats good advice. I advertised a Nagler 5mm T6 on there recently and had loads of responses - it sold within an hour.

There are some great eyepiece / accessory collections here and it's fascinating watching them evolve over time

I expect this to be my final update (really !). I've still got to squeeze the poor little Nirvana 4mm in somewhere - it's a great little eyepiece though and 225x is extremely useful with the ED120, so it thoroughly earns it's place

Indeed. Have a look at post 865 which was a much smaller case, not that long ago. That now gets used for handsets, mains adaptors, torches, cables, etc, etc.

Russell

Yep. I must get a 2nd case too. My higher power eyepieces have nowhere to live at the moment.

Lots of nice glass in there Russell

Trouble is, with the size of these wide / ultra wide eyepieces, you soon run out of room !

I dated my old C8, roughly, using old Celestron brochures, Uncle Rods guide and some old Astro magazines. The ones folks worry about are the "Halleyscopes", ie: the ones sold in advance of the return of Halley's Comet in 1986. It seems to be well know that Meade and Celestron "relaxed" their quality checking during that period to meet the demand !

Mine turned out to be a 1994 model I recall. It had excellent optics but had developed a bit of "mirror flop" which was annoying.

..... I just replaced the thumb wheel ones with strips of cycle inner tube.

That was what I did too. Works a treat

Wow, another full set of Ethoses. :eek:

Nearly - just the 3.7mm and 4.7mm SX's missing

Lovely set all the same. That Pentax zoom is no slouch either. Interesting that you hold both the E21 and N31. I've read of many selling the latter when they bought the former and then having to track another 31mm down as they missed it !

I recently bought an older Moonlite focuser for a refractor. It was not as smooth as I'd been expecting and the drawtube was not square with the body of the focuser but I only noticed this when looking at the focuser from the scope end and noticed that the end of the drawtube was not concentric with the main body of the focuser. To investigate further I removed the drawtube and then found that one of the four ring bearings that the top of the drawtube presses against had split and was just dragging against the drawtube the rather than rolling smoothly with its movement. I e.mailed Moonlite in the USA and got a prompt response. for around $20 they sent be a set of four new bearings and now the focuser is silky smooth even when tensioned up for heavy accessories.

Could this be your problem perhaps ?

Skywatcher / Orion (USA) / Meade Lightbridge are all very similar in optical quality. Orion (USA) uses the same optics as Skywatchers. If you would like to improve the optical quality then Orion Optics (UK) scopes are worth looking at. They tend to be lighter than their chinese counterparts too. You can opt for even higher quality optics with Orion Optics if you wish.

Of course you do have to invest more in better quality optics but that won't be a surprise I'm sure.

My understanding is as set out by Keith above. What I'm not sure about however is the extent to which this still applies to the Celestron SCT's whose optics are now made in China ?.

I've never seen a Skywatcher manual for an ED scope to be honest but there are loads of articles on the web for cleaning refractor objectives. My Vixen ED objective has been cleaned twice in it's 12 year life. 1-2 times a year would seem excessive to me.

I think the FPL-53 element is the rear (inner) one on the ED120 and the outer (front one) is crown glass. I don't know the composition of the lens coatings but the ED range seem to be deeper in colour than the Evostar / Startravel achromat refractors. Coatings are an area where manufacturers like to keep things to themselves, presumably to maintain their competitive edge.

A bit of light dust here and there is quite normal on an objective lens after a few uses. I find a high power lens blower (manually operated) gets rid of most of it.

My Vixen ED102 uses different glass and coatings to my Skywatcher ED120 but they both seem very effective scopes

The front and rear surfaces of refractor objective lenses are coated and some care is needed to avoid damaging them. As it happens I cleaned the objective of my Vixen ED102 a few nights ago. I used the Baader Optical Wonder fluid and their micro fibre cloth. I followed the instructions and sprayed the fluid onto the cloth rather than the lens. The lens has come up very well.

Don't be tempted to take a short cut on this - an objective lens is very expensive to replace, if it could be replaced at all.

.... I know a member on here gave up a 16mm UWAN for a 16mm T5 Nag so it matched others in his box and regretted it......

Yep, that would be me

I should have believed the review that said there was little or no noticeable difference between the two

I'm using a 4mm Nirvana (a clone of the UWAN) for high power planetary observing at the moment. It sits between a 5mm Pentax XW and a 3.5mm Nagler Type 6 but more than holds it's own. Very, very good eyepieces - I just wish the range of focal lengths in the series was greater

A 21mm (2") Nirvana / UWAN and an 11mm would be great additions

A "minimal" set but one of darn fine quality Damo

....Sometimes the lure of the ethos is just too much! .....

That I can quite understand - you can hear it saying "pick me, pick me" in the eyepiece case

I know what you felt like Nick! My ethos slipped out of the 1.25" tal diagonal and fell with a large thud onto (thank the lord) soft wet grass, about a meter to the side was paving slabs!

You are a brave person trusting the mighty Ethos to a setscrew 1.25" diagonal

I observer mostly from a patio so I'm not going to follow your lead I'm afraid

... I guess my thoughts were that a model produced for reviewing would have had careful QC on it optically and it has proved to be very good.69.....

Thats very shrewd Stu

Mmm that would be nice

I am thinking more along the lines of a 127mm ED doublet @ f/7.5 but far more expensive (more a lifelong wish)

My "dream scope" is a Vixen ED150 F/9 doublet. One came up for sale last year (there only a handful in the UK) but the timing was wrong and I just didn't have the readies

I think it's new owner is a member here though so there is hope yet I guess

Very nice collection Stu

....Just need to find the money for a nice largish ED refractor

This is a good substitute for the price of an ED100:

U.K. Astronomy Buy & Sell

Can't find the thread John ???....

I've not started it, as yet. Interesting to read your views on the topic anyway so thanks for posting them

Thats a lovely set of eyepieces and I do know what you mean about those Tele Vue caps

I shall have to turn mine the other way around now !

One question that is getting asked a lot on the forum is why folks are prepared to spend so much on high quality eyepieces like Tele Vues when there are lower cost alternatives that are very, very nearly as good.

I think I know my reasons but I'd be interested to know the rationale that other owners of such equipment have, if that's not being nosey

Edit: To be fair it's not just Tele Vue, there are other brands such as Pentax, Takahashi, Zeiss etc that fall into the same category.

2nd Edit: On second thoughts, this is probably not the thread to have the above discussion in - I'll post the question elsewhere maybe

That looks like a nice old English refractor

It's hard to tell from the photo - will the focuser tube take 1.25" eyepieces or is it restricted to the .965" types ?.

Also you would find a 90 degree diagonal makes viewing easier. You can get one that converts a .965" scope into a 1.25" one which is very useful as you cannot get .965" eyepieces easily any more.

The higher the number in mm on the eyepiece, the lower the magnification. What scope do you have ?. I'm asking because we need to know if it will take 1.25" eyepieces.

A refractor with a 100mm objective lens can show some nice detail on Jupiter under good conditions, with decent eyepieces. The Andromeda galaxy won't appear as more than an oval smudge though.