View Full Version here: : Tiny Mars - the eyepiece view
17-02-2012, 12:23 AM
Observed Mars last night and saw the ice cap and a bit of detail, but just mucking around I put this montage together showing roughly the eyepiece view through my telescope at various magnifications. Mars is around 13 arcseconds diameter at the moment. I don't use wide-angle EPs, and these would be typical views through ordinary plossls etc. 225x is about maxed-out for my 4.5" scope! :rolleyes:
Enlarge to full size in screen because it's quite wide - hope it's of interest. :thumbsup:
17-02-2012, 01:18 AM
Excellent idea Rob.
lets many newbies know what to expect when looking through a scope similar to yours.
Many Telescope ads are very misleading. They show huge planets and full colour nebulas and Giant galaxies.
17-02-2012, 01:29 AM
Great work Rob.
I wonder what the packing box of a wobbletronic would look like if they had "honest" advertising. ? :shrug: :)
17-02-2012, 09:39 AM
Thanks Ken, jjjnettie! Yeah Ken, a post in the Beginners section kinda inspired it. There are no giant planets the size of 20c coins to be seen through the eyepiece of any of our telescopes! Go video (webcams etc) if you want that - Ken will show you! ;)
And 225x is 225x no matter what scope you're looking through, only the width of the field might vary with premium eyepieces. That is, the same view through say a 16" Dob at 225x (using whatever eyepiece) except tiny Mars will be blindingly bright! Your mind is a wonderful thing though, and works to 'compensate' for the tiny size.
So with Mars if you want to see something even reasonably large you need a bigger scope than mine that has the resolution to go to 400 or 500x, but above all you need the seeing to handle it. And that's rare! :)
17-02-2012, 10:35 AM
I observed Mars last night for the first time through my brand new 8" Skywatcher Dob. Similar views to those below through the 6mm EP (200x). I saw the ice cap but there was little contrast between the cap and the rest of the planet - the image was incredibly bright - perhaps a filter would improve contrast and increase my chances of seeing some more detail? There was a breeze and I was observing through the glow of the railway station across the road.
17-02-2012, 11:19 AM
Nice work, Rob. Always gets me how tiny Mars is, even when it is at its closest to us.
The sketching stickies in this forum are a part of showing folks what can actually be seen through a scope. Yes, a nice way to show some clever pencil work, but these images are the only real depiction of what is actually seen through a scope on the whole of IIS outside of the Obs and Vis forum. Probably the only "honest" advertising too, :question:.
Rob's exceptional work with his 114 scope shows what can be had with this scope in good hands. It's not just about a 16" RC, mounted on an R2D2, processed with C3PO, subract this, multiply that...
Just an eyeball, pencil and paper, a real scope and real eyepieces.
Yet no one thinks about sending "beginners" to these threads when discussions are had about what scopes can actually do and what you will see. Hmm..., I might have to do something about that, :juggle:
Bit of a rant, sorry Rob. I really like your intensions.
Keep on sketch'n.
18-02-2012, 12:56 AM
All true Alex, and thanks for the comments (and posting the thread in the Beginners section). :thumbsup:
In the interests of realism, here's what Mars REALLY looks like at 225x on a typical night from my place. :lol:
18-02-2012, 01:07 AM
Great job Rob, please keep it coming.
Many newbies like me would like to know what it really look like when you look through a scope,simply, so you know, you are looking at the correct object in the night sky,instead of scratching your head.
Well done Rob, a great idea. :thumbsup:
As Alex says, even when Mars is at its closest it is still tiny, and newbie people expect a lot more.
I suggest the obs forum to beginners ALL the time, and the reasons why they would learn so much in there. Truly I do... tirelessly in fact. Ask anyone that reads my beginner help posts. :P Don't I Ron? :D:P
Rob, great work you've done here- it'll come in handy for sure. I've bookmarked it for future reference to throw at Beginners. :D
Actually Rob, there's a thread here (http://www.iceinspace.com.au/forum/showthread.php?t=86505) which could use your expertise with a 4". It's about splitting Sirius with a 4".
18-02-2012, 10:44 AM
Good thread Rob,:thumbsup:
I suggest the obs forum to beginners ALL the time, and the reasons why they would learn so much in there. Truly I do... tirelessly in fact. Ask anyone that reads my beginner help posts. :P Don't I Ron? :D
Yes Suzy you do :D
18-02-2012, 11:59 AM
Bless you, Suzy :D
You are a true shining light here on IIS.
18-02-2012, 03:45 PM
Mars is pretty interesting to observe as the surface markings can change as dust storms sweep the planet, but its a small planet only half the size of earth. Nice job Rob, this can really make a difference for people who have never actually seen Mars in the eyepiece:).
Oh, and by the way, has anyone successfully spotted demos and Phobos by any chance, or are they out of the question?
19-02-2012, 05:43 PM
Hard to get excited with a view of Mars that small.
Surely no features are observable at this magnification?
19-02-2012, 11:05 PM
They certainly are Jan (at 225x). As far as excitement goes, just having Mars in the eyepiece at any scale does it for me. The excitement is always what Mars is, not what it looks like. If I really want to see that I'll go to the Astrophotography section! :P
But like anything, you need to spend time. The ice cap was easily visible though. Seeing is the key to it more than scale. If Mars is rock steady and not too bright (you may need a ND or polarising filter in a big aperture scope to reduce brightness), then detail can be recognised. Big detail that is, like Syrtis Major.
But Mars detail is of very low contrast visually, unlike Jupiter with the bands, GRS etc, and may require a bit of practice to draw it out. Your eyes also seem to do a bit of magic to 'enlarge' the tiny disc, bit like looking at the Moon in the sky.
One thing you can't escape from is that Mars has a much smaller angular size than Saturn, Jupiter or Venus and if you want to see much of it you need the combination of opposition and a night of really good seeing. Even to be able to push the magnification to 225x needs fairly steady seeing.
20-02-2012, 01:50 PM
Mars will have an angular diameter of 14" of arc, at opposition on th 3rd March.Surprisingly, it only will take a magnification of 130x, to make its disc to appear, as the full moon is to the naked eye. Though in practise, one would use around twice that magnification, and up to get the best visual out of Mars at this opposition. Of course, seeing is all important. Also at larger apertures one would expect to pick up more surface detail.
20-02-2012, 03:07 PM
It's not my idea and I can't remember where I first saw it, so apologies for not giving credit, but...
The joy of amateur astronomy is not simply what you're seeing. It's understanding what you're seeing and how you're seeing it, and marvelling at the fact that you can see it so easily.
I love looking at Hubble images with crystal clarity and amazing detail that I'd never get out of my 12". But I still get the 12" out, and the reasons are completely different and it means so much more to me.
21-02-2012, 08:00 PM
some very clever AP'er here on IIS posted some amazing pics of one of mars' moons a week ago
check "solar system images"
21-02-2012, 09:18 PM
Well said sir......and I only have a 10 inch dob and more often than not just the IS binos
22-02-2012, 07:05 AM
Moon is 30 arc-minutes = 1800 arc-seconds.
Mars on March 4th is 13.6".
Mars = Full Moon to the naked eye size at 1800/13.6 = 132X.
At 225X, Mars in a telescope is close to 3X the area of the Full Moon to the naked eye. It appears small because there is no "context" other than the edge of the field.
But just how big is the full Moon? Everyone overestimates its size. When I hold out my arm, it's 1/2 the size of my little fingernail--tiny. We see it as large because of its context with the sky and horizon (the "Moon Illusion"). Look at the Moon through a paper towel tube, and it appears quite small.
To see anything other than some vague light and dark areas, you need about 10X on the Moon, which translates to 1320X on Mars!
Well, obviously that's impractical.
So we cheat a little bit and use filters that accent certain features:
#82A light Blue and #80A blue to enhance the ice caps, the limb clouds.
#23A Red Orange and #25 red to enhance the dark markings
#15 yellow and #21 Orange to enhance dust storms and lighter areas.
#30 Magenta to see both blue-enhanced and red-enhanced features at the same time (the "Mars" filters made by several companies essentially do the same with dichroic coatings).
Most of the color filters also suppress bad seeing a little by reducing the portion of the spectrum seen.
And last, a simple polarizing filter can help improve sharpness without dimming as much as most color filters.
Yes, Mars is the toughest planet to observe details on (other than Uranus and Neptune, of course) and it's only close every 26 months. But, if you look often between now and early April, you just might catch one of those super-steady nights where Mars seems rock steady and details just pop out. I saw a night like than in 2003 and drew a map of Mars that helped me identify about 50 named features on Mars, with a 5" scope. But that was a 5" scope at 328X in rock-steady seeing.
You won't catch that night if you don't look though.
Best of luck to everyone.
26-02-2012, 06:08 AM
It is not difficult to see surface features on Mars at all...if you consider the other planets (all under optimal conditions). Jupiter: easy, but the level of detail varies enormously; Saturn: I'd say it is about the same ranking as Mars, although you could start to quibble over what the word "features" means. As to the rest... Mercury? I don't think so. Venus? Do phases count as surface features? Probably not. Uranus, Neptune and of course the asteroids are out of the question. In fact when it comes to Mars I think it's astonishing we can see anything at all on that tiny world.
I'd like to endorse the comments made earlier by Dave about the reasons for bothering to look at Mars or anything else in the night sky. John Dobson years ago took it to an extreme when he commented at a public forum in Sydney that astrophotographers have some kind of disease: there are far better photos available from HST and so on that are far superior to anything they could produce (he said, not me!). But he had a point: people want to see things for themselves, otherwise tourism would be a thing of the past now the internet is here.
About 15 years ago I was running an evening Astronomy course and the members of the group wanted to see Uranus through my 8" Dob. I told them they'd see little more than a small dot, but that wasn't the point. They wanted to be able to say they'd seen it with their own eyes and it gave me a thrill to be able to show them. It's a very human, very valid perspective (no pun intended). I am absolutely hooked on exploring the Moon telescopically and buy books (such as Charles Wood's for example) to help me do so. I do not simply sit in a chair and look at photos and I doubt many of you do either. While I don't share Deep Sky observers' interest, I do appreciate their motives and applaud all those sketches louder than the technological triumph of electronic images (although they're extraordinary too!).
26-02-2012, 10:41 AM
Thanks Pat :thumbsup:
26-02-2012, 05:28 PM
Viewed Mar two nights ago on my 8" sct at 225x.
Just a red blob and could not discern the ice caps.
This is my first view of the Red and I am excited, simply because this is truly my first and at least I know where it is in the night sky.
26-02-2012, 07:49 PM
"Many Telescope ads are very misleading. They show huge planets and full colour nebulas and Giant galaxies."
This is so true.
This basically describes the department store junk telescope cover label on the box.
Those photographs are what you'd see from giant observatory class telescopes and from space probes like voyager,pioneer and galileo spacecrafts.
if it gets young kids started in Astronomy then it is better than nothing
26-02-2012, 10:43 PM
Well said Geoff! :thumbsup:
Congrats on your first view Jeremy!
27-02-2012, 08:49 PM
Words of wisdom there. I was looking at Mars last night at 400x with a 16 inch dob. I needed a moon filter to cut the glare down and see details- it was still very bright! At 400x Mars is about the same diameter as a biro give-or-take and when the atmosphere steadied, I could see the polar cap slightly larger than the head of a pin. At the bottom of the image some of the dark markings were visible VERY occasionally and I *think* there was a bright triangle on the eastern limb (?cloud perhaps).
I'm about 30kms south of Perth so I get a fair bit of sky glow as well as the unsettled air that comes from being right on the coast.
12-04-2012, 10:58 PM
Second night out with my 10-inch dob... Mars was just a blurry, boiling red blob just like the first night out, but I patiently waited and watched. Eureka! I had 5 mins of great seeing in between the clouds and could clearly see the dark regions, the larger polar ice cap, and lots of red dirt. Happy times :)
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