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Jupiter's grey bands!


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Hi - 

I'm the new owner of a Nexstar 127 Mak - I can set it up fine, plus anti-vibe pads and a dewshield, but whenever I target Jupiter I can only see two pale grey bands.  Being high up, it is possibly not poor seeing.  I can only imagine it's light trespass from streetlamps, or (as this morning) the Moon acting like a great beacon.  Or maybe turbulence in the OTA, and I should let the thing cool longer.

BTW, I also use a Baader Neodymium filter.

All-in-all, pretty peeved at lack of colourful bands!  Any further suggestions? Thanks.

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I have a similar scope but 200 mm not 127mm and I can only see grey bands as well, I'm not sure many scopes will show much colour on Jupiter unless in a really dark area, with excellent seeing conditions ... But the GRS when it's in view probably will show as a pale pink colour.

Enjoy though, its tiny and a long way away :-)

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I don't think light pollution has significant impact on the seeing of colour on Jupiter, if anything it might even help by keeping your more colour sensitive cones stimulated.

My eyes are not particularly sensitive to colour in night time observing, and colours are pretty hard to see in smaller aperture scopes. In my 16" I saw quite distinct colours in the banding which I assume is because the additional brightness kept my eyes stimulated to see more of the colour.

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Take the filter out.

All filters remove bits of the spectrum, the neodymium will be reducing a bit of the blue at 520 to 550 nm and a bigger chunk of the green 570nm to 600nm.

Also what magnification are you using?

If too much then you could be reducing the intensity too much. Not sure what eyepieces you have but 80x is adaquate for Jupiter.

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I can make out colours with my Mak 127 , but they are very subtle and you have to spend a bit of time viewing Jupiter before your eyes and brain adapt to the fine details. You will not see it looking as colourful as some of the wonderful images on display on this site. Cameras are more sensitive to colour and the images are often the result of stacking multiple images.

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Colour in Jupiter is much more apparent once the atmosphere settles.  Viewed Jupiter this morning from North Adelaide which is pretty light polluted and seeing steadied enough to see the disk as pinkish, the bands dark reddish-brown and Great red spot a strong orange.  Jupe gets a bit higher here than in the UK, (it was about 45 degrees altitude) which helps. The colours are subtle with an 8 inch although my scope has a smaller than usual diagonal mirror and wire spider, which probably helps as these improve contrast a bit.  This morning it looked it's best a little before sunup with the sky blue rather than black.

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Light pollution is completely irrelevant. The issue is the state of the atmosphere, the extent of light scattering - hence loss of contrast - within the telescope, and also the experience (and expectation) of the observer. I once was able to see an equatorial band using a low-cost hand-held 40mm refractor at magnification x30 through a double-glazed window from a fully lit kitchen in a heavily light polluted suburb. I've also seen Jupiter as a featureless white blob through an 8 inch at a dark site.

Low power, steady air and patience are the best way to get a first glimpse of Jupiter's equatorial belts. Once you've seen them under those conditions you'll be more likely to detect them at higher power and with more air turbulence. When the belts were first observed around the 1640s (by Zuppi, Bartoli and others) it would have been with apertures of no more than a couple of inches.

Finer detail requires steady air, and for colour it's important to deal with contrast. Eyepiece quality makes a big difference, but so does proper baffling of the telescope. My 8 inch Newt shows better planetary detail than my 12 inch, because the 8 inch has less internal light scattering. Part of that is because the 8 inch has a smaller secondary relative to the diameter of the primary. The secondary obstruction is one aspect of light scattering, there are many others. Start by training the eye and understanding the atmosphere, then worry about equipment. But don't expect things to look like they do in photos. The Great Red Spot, for example, is more subtle than images tend to suggest.

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If you look at Jupiter at twilight or dawn, you might be able to see colours on bands. I saw them with my 60mm at 0.9mm and 0.6mm exit pupils (72x, 103x respectively). They are brownish.

I think the reason is that colours are mostly perceived by cones instead of rods in the eye. Therefore if your eyes are dark adapted it can be more difficult to spot colour features.

The best thing to do is to try! :)

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I find that to see the best detail on the planets, I should not be fully dark adapted. When I'm planning on planet observing, I don't take care to have a dark environment, I don't switch off lights. I do however take care not to have lights intruding on the scope light path or reflecting off anything in a way that could contribute to glare.

Light levels that stimulate our colour receptors enough to get the fine details we want to see on the planets will destroy our dark adaptation anyway. +1 to the twilight observation idea!

Spending a long time just looking, is very important to let your brain tease out the finer details. It takes practise to be able to get the fine details quickly, for most people it takes maybe tens of minutes of looking to see the more subtle details. Patience and not getting frustrated are key!

I've been able to see subtle colours with my 80mm scope pretty regularly, so it is possible with practise.

Sent from my SM-G920F using Tapatalk

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My 90mm APO shows rich band color as does the SW120ED and more aperture opens up the detail as like my 10" dob. All these scopes show very good color- the Neo does change the hue however. Eyepiece tone can also make a difference, with my preference being a warmer tone for Jupiter.

The more you observe it the more you will see...

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My 90mm APO shows rich band color as does the SW120ED and more aperture opens up the detail as like my 10" dob. All these scopes show very good color- the Neo does change the hue however. Eyepiece tone can also make a difference, with my preference being a warmer tone for Jupiter.

The more you observe it the more you will see...

I think all of my scopes have shown the same colour scheme on Jupiter, apart from maybe the 70mm refrac. 

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Jupiter is varying shades of brown in my 130mm newt, I have never looked at it with an eyepiece in my 70mm frac so no idea about that, my cameras are mono so no help there ;)

Remember off centre vision will make it harder to see colour, you need to be looking right at it for colour.

/Dan

Sent from my iPad using Tapatalk

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