View Full Version here: : Magnification
27-06-2012, 01:47 PM
What sort of magnifications are you regularly able to use on planets, moon and DSOs and what's your experiences with the so-called 50x/inch "limit", seeing etc. What's the highest you've ever been able to use on Solar System objects and DSOs?
27-06-2012, 02:37 PM
With a small scope (4.5" f8) and chronic bad seeing (deep E-W, west-facing valley in a mountainous area) I rarely get to test high mags on solar system objects. Seeing normally pulls up planets at 112x (8mm ep) or less but very rarely I've been able to go to 225x (8mm + 2x Barlow). I remember one (just one) beautiful clear view of Jupiter at 225x. That is the full 50x/inch limit. Never tested beyond as that is also the limit of my kit. Been to the equivalent of 500x with a webcam (NexImage + 2x Barlow) but that's different - using the power of stacking to compensate for shortcomings, both seeing and optical.
Usually view deep sky at 43x (21mm ep), brilliant richfield views, only to 112x for the brightest (bigger, but the views aren't great). However there are some dimmer objects that seem to respond well to magnification, while others just vanish (small scope). Never been beyond 112x with DSOs (except in other people's scopes!).
27-06-2012, 02:41 PM
And no matter what magnification, I've never seen a ghost in peripheral vision or a 'quantum mechanical apparition'... :rolleyes: :D :lol:
27-06-2012, 02:44 PM
on my 14"sct i am usually around 102x to 209x...using a 35 pan to a 17 nag..no barlows nice crisp wide views...then on exceptional nights like last saturday a faint 14mag p/n with a 6.7 530x seen clearly in eyepiece no bouncing around just perfect!!!!!!!!
honestly it is all to do with atmosphere and conditions....
27-06-2012, 02:46 PM
:D 2 weekends ago I watched saturn cross the meridian for 4 hours ( 2 before and 2 after ) using my 127mm Triplet ( 5 inch ) with my LP 3mm planetary at 320x and it was awsome , the detail seen was impressive . It was so still, it looked like a very detailed photograph .:thumbsup: .
But that kind of power is unusable most of the time , usually around the 200x is all the atmosphere will allow .
27-06-2012, 02:55 PM
I've looked at the Moon & planets through all my 8 scopes, from 2" to 17.5". The 2" aside, typically best I can do is 150X. On those occasions that seeing is better this can be upto 250X. At sea level this is the best I've managed with good steady seeing. Only once was I able to take my big dob to 330X, but seeing wasn't too bad, say 50/50 steady, & again at sea level. I really haven't attempted high magnification on these objects from my customary dark sky site that's at 1000m - I've got other fish to fry at a dark site than the Moon or planets which I leave for when I'm at home.
27-06-2012, 03:25 PM
Typically 108x in my 4" apo, but this stunning night was an exception...
Saturn - planet in Leo
Date: 2008/02/29 at 2300 EDT
Telescope: 4" F5 refractor on alt-az, 5mm and 2.5x, 270x, 18'
Conditions: moon=-, dew=-, wind=-
Seeing: good (Pickering)
Notes: Absolutely stunning at 270x. I would never have believed my scope would support this magnification on a planet, but it did. Huge, detail in the rings, and banding on the disk.
Back Yard Boy
28-06-2012, 03:46 PM
I have a 12" dob and live close (very close) to sea level. I have tried up to 370X on Saturn, but the image appears to be substantially more distorted (presumably by the atmosphere) than at say 230X which I can achieve with my Powermate + 16mm Williams
28-06-2012, 10:40 PM
Typically I get to 175-250x with my 13 and 9 mm Naglers in the f4.9 16". With really good seeing I have occasionally pushed it by using my 2.5x powermate. 440x has occasionally been OK on Saturn and Jupiter at Zenith. PNs and galaxies fare much better.
29-06-2012, 10:51 AM
I find that 80% of my viewing is with my 17mm ethos giving 179x magnification, when seeing conditions are good i add the 2x powermate giving 358x great for viewing planets at the zenith and great for planetary nebula the ghost of jupiter planetary shows great detail usually not seen at 179x, if seeing conditions are not that great i usually stay at 179x or use 26mm plossl with 2x powermate giving 234x.
The most common magnifications i use in order of use are 179x, 74x, 148x, 234x, 358x, 304x from using a combination of 17mm ethos, 41mm panoptic, 26mm plossl, 20mm plossl, 2x powermate.
29-06-2012, 11:02 AM
Gee, has no one here ever gone as high as they can just to see if they could and what the result would be?
If I want good views I'll use 10mm minium on 8 inch (F=1000) or 10 inch (F=1250) scope. Sometimes with 2x barlow. So 125x without barlow or 250x with. All my eyepieces are plossyls of varying quality, so in good seing I'm sure I could go a little higher. The 6.3mm is more usable than the 4mm, but really the 10mm is my lowest eyepiece "of a reasonable quality".
If I don't need the magnification I'd go the 2" eyepiece or my 15" wide superview which is a lovely eyepiece (for the price).
But I have on a couple of occassions stacked two 2x barlows and a 6.3mm or even 4mm plossyl. So on the 10" with the 4mm eyepiece that'd be 312x, 625x (1 barlow) and 1250x (2 barlows). The results were predictably horrible and tracking with a Dob was fun and games, but you have to do that at least once in your observing life. Chasing Saturn, especially if your mount isn't the smoothest can be a real challenge ;-) It was a while ago but if I recall correctly I think 625x as high as I'd go without calling it a smudge rather than a planet so that's close to the 500x on a 10" scope 50x per inch limit that people talk about.
29-06-2012, 11:07 AM
Hi all, I have used 5mm eyepiece in 14" f10 SCT on very steady nights that equates to 50x per inch. That was for viewing Jupiter. Usually find that 200x is acceptable with average seeing conditions. All the best.
29-06-2012, 11:12 AM
For sure everyone has. I have. I actually still do punch my big scope to 1000X, but now only when the clouds roll in and the only thing to look at is the roof-top red aviation light on top of the local hospital to make out the writing on the light's housing, and the bird poop that's splattered over it! :lol:
29-06-2012, 11:43 AM
The most mag I have used on my 16" is 762x with exellent results was on Jupiter on the night of Anthony Wesley's discovery of the comet crash.
The detail was stunning, as can be attested by Jeanette and Paul who where here at the time.
But mines to see the local Hungry Jacks drive through! Either that or trees :question:
29-06-2012, 03:07 PM
I've had a few excellent nights this year, all morning sessions and with the 8" dob. This scope didn't break a sweat at 50x/inch on those occasions. Just a couple of weeks ago I was observing the moon at 600x and it was sharp to say the least, even 720x was possible during those extra steady moments and was alot of fun tracing the hills and mountains along the limb. Earlier this year, I've resolved planetaries as small as 2" at 857x which is the highest mag I've milked from the scope with "useful" results. report here http://www.iceinspace.com.au/forum/showthread.php?t=86258
While Melbourne is famous for its unpalatable climate, it offers decent seeing most of the time. Usually I can expect to use 200-250x for planets, globulars and planetary nebulae and maybe stretch it to 300x on small faint DSOs. If anything, there's less nights with seeing that won't allow mags in excess of about 150x.
Haven't had the chance to stretch the legs of the 12" yet.
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