Which eyepieces for a F/10?

[MARS1960]

My Baader hyperion 8mm modular eyepiece came today, (clear skys

sunday, yippeeee) check it out, i'm new to all this but it's a fabulous versatile eyepiece.

[johnoelliott]

I'm thinking that with your budget, the Celestron 2" accessory kit would be a good start, although I'm not really sure what it would cost you in the UK

[Fordy_638]

Hi Ya Fordy, a very warm welcome to the land of the skywatchers!! excellent scope mate a good choice for the Planets - I think I read somewhere that the 925 is the "sweet spot" when it comes to observing the planets so you will do very well mate nice 1.

I tend to keep it simple when observing Moon/Planets - most nights I can get away with a 12mm EP on Jupiter/Saturn - maybe a little more on Saturn say 12 - 9mm, also MArs is coming around in a few months - Mars can take a little more power - so say anything from maybe 10 - 8mm - very difficult to observe - small and very bright at opposition - also low down this time around so you may need to back off the mag a little as the atmosphere when observing low down makes the disk very shakey/blurry and very hard to pin down detail - but the major landforms - Syrtis Major to name one and the polar caps will stand out very distinctly if the atmosphere steadies enough.

The Moon will take high magnification very well - the upper limits of the scope will work well here - even down below 8mm - but a very small field of view and more difficult to get a sort of "snap to focus" when using higher powers and the atmosphere will dictate your highest powers - but well worth a good look at higher powers - so big and so bright!!!

EP's are very difficult to suggest as there are so many, but as others have said working at F10 allows the cheaper EP's to be used with very good results - I have a set of Hyperions - I think these are good down to about F7 but I only have long focal length scopes so others will chip in here, Also, I used a set of 4000 Meade superPlossl's for such a long time and still use them with my little 127 Maksutov - the longer focal lengths say from 32mm to around 12mm have good eye relief, but the 9mm and 6mm are like looking through pin holes - a bit of an acquired taste - you really have to get your eye in close with these beauties!

The zoom as mentioned will give you a very good range of mags - but the SCT's have very narrow FOV's from about 1/2 to a degree or so - fine for the Moon/Planets - I can spend hours just letting the scope track with the object in the centre of the field - with the zoom, you can quickly change powers to see what suits the conditions, the Hyperion zoom has a click lock so a little clicking sound when you reach 24, 20, 16, 12 and 8mm's but you can also stop in between these points to make the most out of the seeing - not like you have to change EP's all the time.

At F10 the £40 - 50 EP's work just as good as the £100 when you are just looking at the centre of the EP whilst the scope is tracking - what's called on - axis, its only when you position the object away from the centre portion of the field - called off - axis that things begin to show how well each EP corrects here - this is when EP's which are much more expensive - I think there are exceptions like the Max visions and the Explore Scientific - tend to correct aberrations much better giving more pleasing views - this is where things get very personal - some observers can put up with the "defects" of the EP much more than others - its the same as everything hobby wise - as some say you only get what you pay for and on the whole - the more you pay for an EP - the better correction off axis there is - I think it becomes more apparent if you have a Dobsonian scope and need to "push" the scope to track - where as the SCT will happily track at fairly high powers all night.

Not sure if you can get to a club and try out as many EP's as possible - I was in this position a long time ago and just used the EP's which come with the scope - for as long as I can remember - trust me the on axis views are really very nice - my first EP was one of the Meade 4000's a 26mm I think - remembering that I was new to the hobby- so the views were all new to me and I made the most of every clear night - so I think I fall into the "use it and get the most out of it" brigade - its only when you read reviews of EP's that it starts to make you think what all the fuss is about - and at a price point well beyond what I wanted to pay for 1 EP !!! - remember what I said earlier about my Meade 4000 Super Plossl's - YES - I still have them and use them - especially on my 127 Maksutov - looking at the solar disk (with the correct solar filter in place of course!!) is a real pleasure with these little beauties!!

Paul.

[Fordy_638]

Thanks Paul.

Sorry for the late reply but I've been pretty busy, you gave me a wealth of knowledge and I really appreciate you taking the time to reply in such detail.

[spacejammed]

Sorry! My bad! Should have done the maths to work out that a 2mm EP would push your scope past its limit. With a focul length of 1200mm for your scope a 4mm EP will come in right on the button at 300x. However, there won't be many times you'll be able to use it at full mag like that unless the seeing is really good. A 2mm EP is too much for this scope. An 8mm will give 150x. I find a 2x Barlow is better to use with some EP combinations, like 32mm, 25mm, 20mm and 15mm also as you get an easier view through the EP's because the lenses are wider than higher magnification EP's, rather than having to squint into an EP when you get down below 8mm size EP's. This will effectively give you a 16mm, 12.5mm, 10mm and a 7.5mm EPs, so will in effect have 8 EP's for the price of 4. If you splash out on good quality EP's then with a good quality 2 x Barlow this is still a good option to think about in my eyes. I regularly use a 2xBarlow on my ST120 scope and nearly push it to its limit (240x) OK when viewing the moon at least. Not had much chance to test it out on the planets fully yet due to the weather.

Sorry! My bad! Should have done the maths to work out that a 2mm EP would push your scope past its limit. With a focul length of 1200mm for your scope a 4mm EP will come in right on the button at 300x. However, there won't be many times you'll be able to use it at full mag like that unless the seeing is really good. A 2mm EP is too much for this scope. An 8mm will give 150x. I find a 2x Barlow is better to use with some EP combinations, like 32mm, 25mm, 20mm and 15mm also as you get an easier view through the EP's because the lenses are wider than higher magnification EP's, rather than having to squint into an EP when you get down below 8mm size EP's. This will effectively give you a 16mm, 12.5mm, 10mm and a 7.5mm EPs, so will in effect have 8 EP's for the price of 4. If you splash out on good quality EP's then with a good quality 2 x Barlow this is still a good option to think about in my eyes. I regularly use a 2xBarlow on my ST120 scope and nearly push it to its limit (240x) OK when viewing the moon at least. Not had much chance to test it out on the planets fully yet due to the weather.

Loving this comment as was looking through posts for tips on EPs In particular smaller ones. The concern was being able to see through them, however this post was a lightbulb over head moment realising that there is a use for my x2 and getting a wider ep rather than squinting and not enjoying.

Clearly I joined the right astronomy site.