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I'm saving up for my next eyepiece, and I'm wondering what to get.

Currently I've got a 9mm TS Planetary giving 150x magnification,a 15mm plossl, and a 25mm plossl giving 50x magnification and a 1 degree field of view.

I'm wondering whether to get a low-power eyepiece or a higher-power eyepiece.

A 32mm plossl would give me only a 1.3 degree field of view, so would that really be worth the bother? (i.e. a .3 degree increase). I don't think that field of view would be wide enough to frame most open clusters for example.

At the higher power end I'm thinking of getting either a 6mm or 5mm TS Planetary, giving either 220x or 265x magnification. My telescope manufacturer says my scope can handle up to 240x magnification, but if you follow the twice aperture rule strictly it can only go up to 204x.

I'm just worried I will get the 6mm and regret not getting the 5mm...

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hi there

In terms of maximum mag I tend to work on 1.5x aperture in mm and this gives around 150x but I think with your scope you'd maybe get to 200x at a push but the image might get mushy.

Unfortunately, I think you can only use 1.25" eyepieces and the 32mm gives the widest field possible in a 1.25" eyepiece (assuming it's a 50 degree field eyepiece). Being able to use 2" would open things up a lot. Getting the 32mm is certainly worth it in my view and it will almost certainly make finding things easier as well as for wider field viewing. I'd recommend waiting for a Televue plossl which you might get used for £50 but in your slow scope you could use most eyepieces with good results. The focal length of course is what restricts your field of view.

Don't forget of course that an optical finder can often give great views of larger open clusters like the Beehive etc.

Good luck whatever your choice.

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Id say give the 5 or 6mm planeteries a miss. I have a 5mm giving 200x in a larger 120mm refractor and it is definitely pushing the scope to its max - i sometimes wish i'd gone for the slightly lower power 6mm to get a crisper view, even though the planets etc would be a touch smaller. Dont get obsessed too much with magnification, 265x isnt really viable with your scope.

have you thought about getting a decent barlow lens (if you dont have one already) that you can use with all your EPs? The 15mm plossl with a 2x barlow will yield about 175x mag with your scope.

With a slow scope like yours you dont need to splash the cash too much on eyepieces. Ive bought 2 televue plossls, and although i love them like they were my own children, I sometimes wonder if the money could have been better spent. Saying that though, if you do buy high quality EPs, they will work nicely in any scope which you choose to buy in the future.

Paradigm/explorer ED eyepieces seem to be very popular at the moment, and great value. 1.25" Eyepieces. I really want to try one of these highly rated cheapies!

Low power is nice for just mooching around the stars with; open clusters etc, and for finding things. I use a 32mm 2" EP and LOVE it!

happy shopping

w

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But isn't the OMNI 120 an achromat? From what I understand, achromats don't stand high magnification very well (although Celestron do advertise mags of up to 280 for the OMNI 120). I'd be interested to hear how far other owners of maksutovs have pushed their scopes...

I've just seen TMB 6mm planetaries for sale on ebay for 36 pounds - at that price, what could go wrong?

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The 6mm TMB planetary is great and with my 12 " scope it's my most used eyepiece but with a scope of lesser aperture it may not see much use at all. The 9mm gives you all the magnification you need.

The TeleVue 32mm plossl is my second most used eyepiece and has done good service with every scope I've owned.

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Well I asked for advice and everyone is telling me to not go for the 6mm... I'm not convinced, because at 150x things like saturn's rings remain razor sharp - I'm sure I could push the magnification a bit higher.

I've got a great idea. I'll get the 6mm, and if it's not right for my little scope, I'll buy a bigger scope to go with the eyepiece!

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Well I asked for advice and everyone is telling me to not go for the 6mm... I'm not convinced, because at 150x things like saturn's rings remain razor sharp - I'm sure I could push the magnification a bit higher.

I've got a great idea. I'll get the 6mm, and if it's not right for my little scope, I'll buy a bigger scope to go with the eyepiece!

;)

I bet you will eventually anyhow.

yes, the 120mm is an achro and I get maybe 160-180x out of it unless the seeing is brilliant. For this reason, I am considering an 8" f8 newt/dob.

you may get higher mags with your scope but I have never used a Mak. I agree that you may as well go for the TMB 6mm and see how it goes. worst case is you sell it on for £30 and buy something else if unsuited.

go for it I say. in all fairness I am pretty much a beginner too and am just commenting on my own experiences. usually when I have gone for something I was sure would be OK it was. also, when I bought something I thought I'd be unhappy with, I also was, so trust your instincts and knowledge of your own scope! :eek:

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I tend to go to a max of 1.2-1.5 times diameter with my Mak. After that the image deteriorates and a sharp image is better then a fractionally bigger image.

You say that the scope states 2x dia, well they could state 3x or 5x, just have to stick in a smaller eyepiece. The image would be utter garbage but mathematically the value is correct.

Bet the box has an image taken by Hubble on it as well.

You mention Achro's, well if I recall Meade say their ETX 80 (achro) will take 3x dia. It will not, and any one that believes it has been taken in by marketing.

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OK, buying a 6mm Planetary from Modern Astronomy as we speak. I can't resist. I'm inexperienced enough to still suffer from Magnification Fever. After I recover from that, I will develop Aperture Fever...

I'll update the thread with a report of how it works out.

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great stuff

I bet you won't regret it. even if you cannot instantly see detail with the new eyepiece, it will be there, you'll just have to wait for short periods of clarity.

That is exactly why i bought a 4mm Celestron Omni.........for observing planets during those fleeting moments of clarity.

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Paul, what mag does a 4mm plossl give you?

All I need now is a wide-field eyepiece. I'll save up for a second-hand 24mm baader hyperion!

My scope has an apeture of 130mm, focal length is 650mm........... so that is a magnification of....what? .............162x

If it is a widefield EP you want then you should be looking for something around 30mm (with a 55 AFOV) or better.

Can be bought 2nd hand here for £20-30.

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The 24mm hyperion has a AFOV of 68 degrees, so if my maths is right it has the same true field as a 32mm plossl, but with more wow factor. I'll have to save up for months though - it'll be the most expensive accessory I've bought.

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The 32mm will have less wow but a brighter image because of its lower magnification. Take your pick.

I personally would go for the less WOW but brighter image. It really doesn't matter what EP you have...............you will always have WOW moments with them. Its better to have a brighter WOW moment with lower mag then a duller WOW moment with higher mag.

I recently bought a Vixen NPL 30mm EP from a fellow SGL user and let me tell you it is giving me a hell of a lot brighter (ever so slightly lower mag) WOW moments then i ever got with my trusty 32mm Celestron Plossl.

The Vixen NPL EP range are middle of the road in cost ($30-40) but they punch way above their weight. Image is sharp right across the FOV. Image is BRIGHT.

I found the Ring Nebula a while back using my 30mm Vixen NPL even though i wasnt actually looking for it.

I am surprised that no one has yet mentioned buying a Barlow lens or a Powermate.

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I personally would go for the less WOW but brighter image. It really doesn't matter what EP you have...............you will always have WOW moments with them. Its better to have a brighter WOW moment with lower mag then a duller WOW moment with higher mag....

A higher magnification eyepiece with a wider field of view (eg: Hyperion 24mm) can show as much sky as a 32mm plossl with the advantage that higher magnification darkens the background sky so faint DSO's are easier to spot.

A 32mm plossl is a lot less expensive though and will still provide some very nice views.

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A higher magnification eyepiece with a wider field of view (eg: Hyperion 24mm) can show as much sky as a 32mm plossl with the advantage that higher magnification darkens the background sky so faint DSO's are easier to spot.

That is EXACTLY what my 30mm Vixen NPL does against what my Celestron 32mm ever did. It gives better CONTRAST, so those DSO's jump out at you more.

Thats why i love it so much. It is a far better EP all round. My Vixen 30mm is now my favourite EP.

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John is right - magnification brings out small DSOs that might not be seen at lower power. Equally, some large DSOs will be best seen at lowest power. It's why we all end up with lots of eyepieces.

Strictly speaking, the contrast of DSOs is independent of magnification: the object is darkened as much as the sky. But our ability to detect low-contrast objects is dependent on size, so magnifying a small DSO to the right size will make it pop into view. This effect becomes particularly noticeable if you use a zoom eyepiece.

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Used the new 6mm EP tonight!

Double Double: I could split it much more easily with this new eyepiece. My friend struggled to get in the right position with this eyepiece. I also struggled a bit, but had good views when I had the right spot.

Moon: Wow. OK, there were ripples everywhere, but under the ripples, the image was sharp. Could see loads of detail, texture, shading and relief I have never seen before. Very pleased. My friend managed better with the moon, and looked for a long time at it.

THe moon is very bright, not much else to see - tried a few faint things but couldn't find them.

If it stays clear I will wait up for Jupiter.

I would say 220x magnification is doable with my 102mm Mak, at least on bright objects and stars. Very pleased with the purchase.

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I am surprised that no one has yet mentioned buying a Barlow lens or a Powermate.

It's because you don't "need" one with a Mak. The slow F ratio means that - for simple designs like Plossls or Orthos - you don't need to resort to uncomfortable short lengths.

You also tend to use fewer eyepieces overall with a Mak.

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  • 3 weeks later...

I had another go at Jupiter with the mak at 220x magnification. I have to agree it gets mushy over 150x (it was even a bit mushy at 150x last night, so the seeing must have been very poor - at 50x Jupiter oozed about like an amoeba). Had a good look at Jupiter at 150x - I could see the Northern Equatorial Band, and a trace of another band to the south, closer to pole.

I've tried jupiter twice at 220x now and been disapointed both times, but conditions haven't been optimal yet. Nevertheless, the higher magnification definitely works well on the Moon, globular clusters and double stars, so I'm pleased with my purchase, especially after the stunning views I had of the moon on my first outing with this eyepiece a week or two ago.

One thing I noticed while looking at jupiter with the TS Planetaries is quite strong internal reflections around Jupiter. Not as bad as with a SkyWatcher LER eyepiece I tried once, but more that I expected from an eyepiece that claims to minimize the reflections.

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