View Full Version here: : Not much contrast on Jupiter: simplest step to improve?
marmotte
18-09-2012, 05:01 PM
Hi all
A few months after having bought my first telescope, and after many very fine evenings of Saturn, Moon and a few DSO watching, I eventually managed to wake up early to have a look at Jupiter.
Whereas it was a very satisfying sight, I was a bit disappointed by the lack of contrast of the image. The focusing was sharp, and the image was very bright (too bright?), but colour bands were not really visible at all, the whole disc was a very bright yellowish colour, with barely any variations.
That was the case regardless of what EP I used, with or without barlow.
I hadn't cooled down the telescope for very long, but it was a warm night and inside temperature was not much more than outside...
I was wondering what would be the next stage to improve that ? I was plannign to buy a 5 or 6 mm TMB one of these days, but is there something lse that I could do before to improve this side of things?
THX
bojan
18-09-2012, 05:22 PM
Expectations vs reality..
Published (enhanced) pictures of Jupiter are not realistic, really...
In time, your eye will become more used to notice faint differences in contrast and details will eventually pop out.
Also, details visibility will be dependent on transparency of the atmosphere and presence of winds high above the ground (streams).
brian nordstrom
18-09-2012, 05:26 PM
:thumbsup: Hi Pierre and :welcome: mate , jupiter is 440 million KM's away and we look at it thru about 40km or atmosphere , and thats where seeing starts , we only get around 10 nights a year when seeing is as good as it can be , the rest of the time its either :sadeyes: cloudy or the seeing is carp , thats a fact of life living here on the Earth's surface .
Dont expect Hubble like images all the time , keep you magnifications at around 100 -120x ( an 8mm -10mm ) eyepiece with your scope . By the way what eyepieces do you have ?
I had one of the scopes that you now have and it gave really good views of jupiter at the 100x to 150x . Only good nights allow you to get to 200x + .
Take your time , train your eyes ( they are mussels ) and things will improve over time . ;).
Use this time to view deep sky ? your scope is one of the best for this under 10 inches apateure , enjoy it mate .:thumbsup: .
Brian.
brian nordstrom
18-09-2012, 05:28 PM
;) spot on , I was typing as you said exactly the same things ,, compressed of course , Bojan .
Good advise .
Brian.
MattT
19-09-2012, 08:10 AM
Brians correct about the number of days...nights that are any good, but 10 :eyepop: really can I come and live up there Brian? Down here in Melbourne it's more like 2 or 3 at the most :help:
ZeroID
19-09-2012, 09:09 AM
I am lead to beleive that a Blue filter may improve contrast and reduce glare on Jupiter viewing as well. Have yet to try it myself.
jjjnettie
19-09-2012, 01:19 PM
One thing to get worked up about with Jupiter, and you can see these on all but cloudy nights, are moon shadow transits.
They are amazing!!
If you're lucky you may even get a double shadow transit.
So get hold of the Astronomy 2012 year book, and check out when the next one is happening.
That should keep you busy while waiting for one of those rare nights of good seeing. :)
marmotte
20-09-2012, 09:26 AM
THX all.
My eypieces are 9 and 25mm GSO mm super plossl and a 2x GSO barlow.
I was not expecting magazines like viewing either. My disappointment is somehow "relative" to what I have been seeing so far on Saturn or even Mars. I believe I could see the bands on Saturn, on many days, with a better contrast than those on Jupiter, somehow because of Jupiter being "too bright?"
I'll keep an ey for transits!
THX
brian nordstrom
20-09-2012, 04:00 PM
:thumbsup: I watched a shadow transit at 4am local time here in Darwin this morning , cool , like a tiny black bullet hole on Jupiter .
Brian.
jjjnettie
20-09-2012, 07:00 PM
In the October edition of "Sky at Night" magazine, Paul Abel has written a piece on viewing the Planets with filters.
He just posted this on FB.
" If you want to learn how to enhance your views if the planets with filters, check out my article in October's edition of @skyatnightmag"
Varangian
20-09-2012, 09:16 PM
Hi, I don't use colour filters for planetary viewing, I have used a number of them including different brands and I'm just not convinced about them, maybe why they are only 10 bucks a pop and I try to avoid extra pieces of glass where possible. Occasionally I will use a neutral density filter on the moon and Jupiter only to reduce a bit of glare, but that's about it. I find I see more features on these targets with the neutral density filter than I ever have with a coloured filter.
brian nordstrom
21-09-2012, 07:56 AM
:) Hi agaim Pierre, just a thought , how well is your scope collumated ? An out of collumated scope wont perform up to its full potential , by a long way .
Brian.
Shiraz
21-09-2012, 09:21 AM
yes, check your collimation and give the scope an hour or so to cool, but don't expect much from Jupiter right now. we are under a very strong jetstream and looking through it at low angles sandblasts the view. the only chance of getting some of the lower contrast detail is when the 200hPa jetstream is below about 50 knots. http://www.bom.gov.au/australia/charts/viewer/index.shtml?type=windbarb&level=200hPa&tz=AEDT&area=Au&model=CG&chartSubmit=Refresh+View
doug mc
01-10-2012, 12:43 PM
Trying to see detail on jupitor is very tricky. I have been observing it now for several years, with reflectors from 6inch to 10 inch. Having discovered all of these chinese mirrors had some amount spherical aberation i replaced my currant 8inch mirror with a Parks primary from the good ol USA. Very good optics mached with exelent seeing are needed to resolve detail in the belts of jove. The detail is not high contrast by nature like the moon. As others have said, develop patience, collimate your newt, cool it, and hope for good seeing. :thumbsup:
Geoff45
05-10-2012, 02:23 PM
I sometimes have a look at observations from the middle of last century and wonder what's happened. Have scopes got worse? Have observers lost patience with careful viewing, expecting to see Hubble type stuff through their scope? Has seeing got worse?
Here is a quote from B M Peek's The Planet Jupiter from 1958
With a 2" telescope...the shadows of the satellites may be readily seen as little black dots...on the disk of the planet. A 3", working under good conditions, will reveal that the belts....are not entirely regular but show darker patches or condensations and sometimes projections at the edges. An occasional bright spot may be seen with a 3", particularly if it partly overlaps one of the belts.
These old guys, often using only a 6" scope, would record times that features on Jupiter crossed Jupiter's central meridian to an accuracy of 2min. In this way they could track the atmospheric currents in the clouds
Bloody amazing!
cjamo9
06-10-2012, 12:22 AM
i have had improved viewing of jupiter using a blue filter, moon filter and a moon and skyglow filter from baader. im waiting on a baader contrast filter also.
ive tried the baader uhc-s filter on jupiter as well. sounds like an add for baader hey.
i recon they all help.
PS. when you get yourself a zoom, get the pentax over the baader, seems much clearer to me.
Pinwheel
06-10-2012, 03:24 PM
+1 without correct collimation I had jupiter looking like a waxy blob. All fixed now. Try wearing your polarized sunglasses next time just to see if it helps, No point buying filters if you don't really need them & lastly :welcome:.
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