Focal Length and expensive EP,s

[Bigwings]

I keep seeing members lusting after EP's costing an astronomical:D price. Now my experience is that my f10 SE8 SCT is very forgiving and gives great results with EP's that would not perform well with a fast Newt.

I wonder if those of us with experience of fast and slow scopes have a view on the cost of EP,s when advising new members on scopes to buy.

Is it true that for a visual observer an SCT (and focal reducer) will provide and economic path through the hobby / science / obsession of astronomy when considering the overall cost of EP's, filters etc.

Answers on Pentax XW 40mm 2" box preferably full.

[John]

That's a good point - slow scopes are considerably more forgiving on eyepieces. Maybe the the trend towards faster scopes has been driven by the rise in popularity of deep sky imaging ?.

It's certainly a factor that should be pointed out when advising on a potential scope purchase - it's so easy to spend more on eyepieces than the scope !.

[wulfrunian]

I agree that it's a good point. When I bought my f4.8 dob, I didn't realise it was going to start me off on a lust for expensive eyepieces, this hobby sucks you in! I assume the reason for the faster dobs is that they give you so much more aperture versus portability.

[LukeSkywatcher]

I'm cheap and easy to please. I use the same EP's across all my scopes (f11,f5 and f400?).

I guess it doesnt really matter as all the scopes are 5" or less in apeture.

[great_bear]

I wonder if those of us with experience of fast and slow scopes have a view on the cost of EP,s when advising new members on scopes to buy

Yes.

I certainly do. Even though I might not explicitly state it.

It only took a few minutes with a Barlow and my wife's 130P telescope to make me decide that - for the sake of eyepiece costs - I would never buy an F5 scope again. You don't have to have an F5 scope for wide views (provided you've got a 2" focusser), and the increase in planetary performance with slower scopes - as well as the flexibility to enjoy much cheaper eyepieces - made me decide a long time ago that slower is better.

As Ghandi himself once said "There is more to a telescope than increasing its speed..."

(or he might have said "There is more to life than increasing its speed..." - I'm not sure... - OK I made that last bit up - but the point still holds... )

On the flipside however, there is more to an eyepiece than its performance in fast scopes. There's better glass, better baffling, better build quality etc. all of which are just as desirable even for slow scope owners. This is my current dilemma. I don't need - nor can I justify - expensive eyepiece purchases. But the cravings for more Tele Vue chunkiness just won't go away...

[Rossco72]

Most things in life seem to work within the 80:20 rule.

You can have 80% of the performance for 20% of the cost but that last 20% is just exponential to achieve.

It still strikes me as ludicrus that you can buy a whole GOTO scope, mount, battery etc. for less than the cost of an Ethos....

[Astro_Baby]

Well I dont necessarly hold with the idea that unless you buy some mega eyepiece your F5 scope will produce bad views. Most of my eypieces are in the sub £150 bracket and work well enough with an F5 scope. OK there may be trifling aberrations at the edge of the field of view but to be honest even when I plug in an eyepiece that cost what the scope cost I hardly see any real difference. The edge of the field is a bit sharper but by a strange quirk of fate I dont happen to have fisheyes in my head and being only human my own eyeballs dont happen to have a very wide field of view.

I compensate for slight edge abberations by the rather revolutionary technique of moving my telescope to aim at the centre of the object - I know its radical but I quite like it. Its one of the reasons I like tracking - I dont have to worry about the target object getting to the edge of the eyepiece and can use the eyepieces 'sweet spot' for as long as I want.

I seldom aim the scope so that my target is at the edge of the FOV so I suppose I never really see the terrible edge performance. All I see at the FOV edge is with my peripheral vision which isnst actually that sharp in humans and even less so with my eyeballs.

At F4 its a different story and eyepieces start to show their faults rather badly but I find almost any half decent modern eyepiece performs tolerably well in an F5 scope.

My only compaint with an F5 is the poor contrast performance on planetary objects but then thats why I have a Mak and a Frac.

I do think the 'you have to have mega eyepieces in an F5 scope' is somewhat overstated for any but the most demanding observer - and lets face it - few of us oldies have the eyeballs to really appreciate the views anyway.

[Rossco72]

I still think that £150 is a lot for an eyepiece, for me £50-£120 is mid priced and anything over is premium....

Bearing in mind the eyepieces supplied with the scope were probably £15 or less.

[great_bear]

I do think the 'you have to have mega eyepieces in an F5 scope' is somewhat overstated for any but the most demanding observer - and lets face it - few of us oldies have the eyeballs to really appreciate the views anyway.

I agree with Rossco that many would consider £150 quite a lot, and tend to think more of £30 per eyepiece when starting off.

It's also the other way around - that oldies are more likely to see edge aberrations than younger people.

It's important to consider that other people's eyes may not be quite so fault tolerant as your own. You clearly see things differently from me, because you've stated in the past that the 25mm Super eyepiece in combination with the Explorer 130P wasn't particularly unacceptable in edge performance, whereas for me that combination was intolerable..

So it's not "overstated" as such - it's just worse for some people than it is for you.

[SiriusB]

Just a few thoughts on the subject:

1)Going back to the original post:I Think those the possible pitfalls of using cheap eyepieces with low focal ratio scopes should be sounded out a bit more,particularly to those new to the hobby.

2)That said i had a peek through a 6"f5 Newt recently with a 25mm Super ma, & i was suprised how good the view was-more than acceptable to me,& i really didn't expect it to be.But as Great Bear says, whats acceptable to one pair of eyes aint necessarily so to another pair.

3) there's always the humble barlow lens-it can sometimes work wonders,rendering an eyepiece usable in a fast scope-Ok, personally i don't like the things, but playing devils advocate, its a cost effective solution? yes/no?

4) You get what you pay for, if cost is an issue, you have to accept compromises.

I don't like spending more than £50 on an eyepiece,so i accept the shortfalls.I did spend £70 once, & ok i admit it was worth the extra twenty quid,as no doubt the premium eyepieces are to those who appreciate them.

5) My rough rule of thumb on edge distortion is: Still looks like a star: Excellent, looks like a pregnant star:thats ok. looks like a seagull,tick mark,cross,cone or any other geometrical shape:not good!

6)Being new to SGL, its nice to discover there are still plenty of people using eyepieces, & i thought i was the only one! Lol.

[Rossco72]

Sirius there are plenty of observers on SGL, and almost as many opinions....

Each one is valid and all need to be considered when taking advice on gear. Thanks for your input and welcome to the forum.

[PeterW]

Try the uwan series from william optics. Fastbscopes have probably been driven by the USA big dobsonians brigade, big Dobson with long focal ratios are not worth contemplating! With an sct you could put an f6.3 reducer in and then your eyepieceshave a wider field of view and still not stress you eyepieces too much.

Nagler addiction is bad, ethos addiction worse. I am now finally 'at ease' with my eyepiece addiction.

PEterW

[great_bear]

4) You get what you pay for.

Ah but you don't get what you pay for - either in life or in astronomy. That's the point. If you did, then choosing eyepieces would be a lot easier. The phrase "you get what you pay for" is just a bit of puff that salespeople say to get you to pay more money. Folks are brainwashed into believing this, and they repeat it because it sounds "wise" without really thinking it through.

Working as a Product Designer of high-tech devices, I find it fascinating the creative lengths that customers will mentally go to in order to bend reality to fit the comforting (but untrue) saying that "you get what you pay for"

If you sell a cheap product cheaply, people will say it's cheap rubbish. Sell the same product for more money, and people think it's a bargain, sell it for a lot more money, and people will start ascribing mythical excellence to the product. Funny how people are like that. If people really knew how much the factory costs were of products, they'd feel differently.

The size of production runs (for example) dramatically affects the price of eyepieces. This means that a low-cost eyepiece may well perform better than one costing substantially more. Similarly, there's exchange rates to consider.

Orion USA products are (generally, but not always) more expensive compared to the competition. Sometimes people think it's because they have a higher quality standard or have "better coatings" or some other myth. Nope! It's simply the way the distribution costs work out when retailing their products here in the UK (i.e. no-ones being ripped off as such) but in the USA there wouldn't be such a price difference, and no need to creatively "invent" mythiclal reasons for the price differential.

In summary, there are some expensive eyepieces that are really not that great at all, and similarly there are some bargain products that perform incredibly well. And sometimes, there's a price difference just because people want to take more money from you - and you'll willingly hand it over because you equate cost with a product being more "special".

It's as simple as that...

So when assessing eyepieces, it's a good idea not to let price prejudice your evaluation - there are some excellent low-price eyepieces out there.

[Moonshane]

Working as a Product Designer of high-tech devices, I find it fascinating the creative lengths that customers will mentally go to in order to bend reality to fit the comforting (but untrue) saying that "you get what you pay for"

this is of course the 'eyepiece-onimical constant', a related (and original) version of which was made famous by Einstein.

As Stuart said, it's the sort of subject where if you ask 20 people you'll get 20 answers. even when you have 'the best of the best' (whatever that is to you) you still have the craving to just get that bit more performance and change things about!

a couple of things not mentioned so far which I see as important personally but you may not:

1) As an example, Televue Radians are reasonably priced used at £100 approx. I once had two (14mm and 18mm) and was considering a 12mm too. As it happened a 13mm Ethos came up at the right price and at about the same as the three Radians. It covers the same field of view but at more magnification than the 14mm and the 18mm and thus more contrasty with a dark sky. therefore this particular Ethos model is actually replacing three £100 EPs so the cost is not as high as it might seem (flawed logic I know but it works for me)

2) Having less eyepieces means that you are swapping them about less as you constantly look for that perfect magnification. therefore you spend more time actually observing.

3) Top quality EPs do hold their value very well. You can usually buy eg a Televue, try it out and use it - keep it if you like it and sell on (usually at the same price even if there's a time lag between the two) if you don't.

As a result of the above (partic. points 1) and 2), I now consider field of view rather than magnification for anything less than 150x magnification when choosing EPs and at the higher magnification end find that a 10mm, an 8mm and my 6-3mm zoom cover all of the requirements.

I am in the know that I'm lucky I can afford them and definitely appreciate them bracket (although I have to sell eg books etc to fund them). Not long ago I had very little money at all and hence I really do appreciate them. I have set myself a 7 eyepiece maximum rule now as I feel this will cover all my 'angles' and therefore if I buy another, I have to sell at least one.

Hope this adds some food for thought.

[great_bear]

even when you have 'the best of the best' (whatever that is to you) you still have the craving to just get that bit more performance and change things about!

Indeed... It's unbearable - and even though I like to get the best value I can, that didn't stop me from splashing out on a Tele Vue Panoptic today!!...

Top quality EPs do hold their value very well. You can usually buy eg a Televue, try it out and use it - keep it if you like it and sell on (usually at the same price even if there's a time lag between the two) if you don't.

This "value" argument is a very compelling one. If you save a little money each month, why leave it as cash in the bank? Why not convert it into eyepieces? You can always (as you say) convert the eyepieces back into cash when you need to - and after all, it's what the bank does with your money anyway (although I think I'm correct when I say that eyepieces are not normally the Bank's first choice of corporate investment...)

I now consider field of view rather than magnification for anything less than 150x magnification

It's a sound strategy I think.

[John]

The tendency for good quality eyepieces to hold their value, following the modest depreciation from new, does help justify the initial outlay I feel.

I've just sold 3 Naglers which were used when I bought them - the year or so I've owned them has cost me around £20 I reckon - not a bad deal, all in all

[Moonshane]

ha ha - bad luck GB - you are now officially hooked!

one thing's for sure, you won't be getting much interest on your dosh to invest in 'enjoyment'

BTW I am in now way (unfortunately) related to anyone at Televue!

[SiriusB]

So when assessing eyepieces, it's a good idea not to let price prejudice your evaluation - there are some excellent low-price eyepieces out there.

Completely agree with you,...I still suspect if you want "the best" whatever that means to you personally, then its going to cost.

[michael.h.f.wilkinson]

I went through all sorts of EPs, and my experiences are as follows: The Huygens and similar plastic garbage EPs which are no good are now thankfully becoming rare, and I only ever got a few accompanying my little Konus 4.5" short Newtonian. I only bought the Newtonian after I was allowed to test the thing with my Vixen and Celestron Plossls, and the Vixen LVs. The shop's owner also wanted to look, and was blown away with the difference.

I always went for descent quality EPs (Circle-T and Vixen (circle-V) symmetrics and orthos), if only for the better FOV. I used them to great effect on my old 6" F/8, enjoyed using them, and learned a lot.

Then I got my C8, and got a set of very decent Plossls. Learned more, enjoyed more, and had a lot of fun. I did replace the 10mm with a pair of Vixen LVs at 7 and 9mm respectively, mainly for better eye relief (I wear glasses and have astigmatism). These were more expensive and quite a bit better.

Later I systematically replaced the whole lot with premium EPs, starting with a 40mm TMB Paragon, which fitted nicely into my new 2" visual back. That really enhanced the scope. The image quality and FOV were so much better than that of the Vixen 36mm Plossl. The Paragon is a much better solution for wide-field than the 0.63x reducer combined with the 36mm.

I now have a small set of high end EPs, which I also bought with the option of moving to fast scopes (an 80mm F/6 triplet, or 12" F/4.7 Newtonian).

I would not advise starters to buy such expensive EPs immediately. First learn to observe with the very decent EPs that can be had for modest sums, and only when you feel that you want to go for more expensive EPs, check them out at star parties, and see the differences, preferably on you own scope. However, when replacing "starter" EPs with something better, consider that buying top-notch EPs means you are less likely to replace them later, ultimately spending less money. Furthermore, a few good EPs (I have four, and will likely go no further than 6) is much better than many poor ones.

[beetlejuice]

Meade 5000's - very underated. I use 'em in all my scopes. They perform very well in my short focus 'fracs, though performance drop off at the edge is more pronounced. Reviews on Cloudy Nights show 5000's in their various versions, give TV's a very good run for the money - beating them in some cases and, of course, at a much lower price.

[Stardust]

I started with Meade 4000's (still have a 15mm, just seams nice) and was happy with them for a couple of years and then I tried a Pentax!

I'm very pleased with my Pentax eyepieces, got hooked after getting an Xl 10.5mm and have gathered a few over the years, mostly secondhand. Have a couple of Panoptics, but prefer the former.

My mate has just bought a GSO F4 and I know he likes observing too, think he's suddenly going to realise some of his eyepieces aren't going to be that great. Will be interesting to look through it.

[michael.h.f.wilkinson]

Meade 5000's - very underated. I use 'em in all my scopes. They perform very well in my short focus 'fracs, though performance drop off at the edge is more pronounced. Reviews on Cloudy Nights show 5000's in their various versions, give TV's a very good run for the money - beating them in some cases and, of course, at a much lower price.

The 5000 series is very good, but the Naglers have dropped in price over here, to the extend that the difference is minimal (compared to Series 5000 UWA). My 14 is very nice, but I am going to try a 12 T4 and a 17 T4 because I find the eye relief of the 14 a bit tight. It not as comfortable as my 22 T4, though every bit as sharp. Some claim that the Nagler is sharper at the edges, at the expense of more pincushion distortion, but I see little difference in either property.

[great_bear]

Some claim that the Nagler is sharper at the edges, at the expense of more pincushion distortion.

I thought that was a SWA vs. Panoptic argument - rather than UWA vs. Nagler?

[great_bear]

Meade 5000's - very underated. Reviews on Cloudy Nights show 5000's in their various versions, give TV's a very good run for the money

The SWAs and UWAs are very well-liked - some focal lengths more than others - but I've never seen anyone claim that the 5000 Plossls are special in any way...

[michael.h.f.wilkinson]

I thought that was a SWA vs. Panoptic argument - rather than UWA vs. Nagler?

I have seen these claims for both. Maybe its just a different set of design choices favoured by different designers.