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Jupiter dazzling bright


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Saw Jupiter last night using my SW 114mm newt reflector from north london. It was accompanied by 4 moons. Everything looked pin sharp with a 25mm lens but too bright. How do I reduce the brightness and see more detail. Is it a matter of increasing magnification or using a filter of some kind of both?

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With the likes of Jupiter I find that I can see more if my eyes are NOT use to the dark. Looking at a bright light, like my phone screen, can actually help. I’ve also got some really good views very early in the morning as the sun was coming up - in other words the sky wasn’t dark - although now, at this time of year, that might not be possible. 

I also have a variable polarising filter which can help…

https://www.firstlightoptics.com/moon-neutral-density-filters/variable-polarising-moon-filter-archived.html

And as mentioned above higher magnification will help as long as it’s not too high. I do have a SW 114 Newt and as long as it’s a good night 100x - 140x (if lucky) is best. 


Also bear in mind that the jetstream has been right above the UK in recent days. This tends to make Jupiter and the planets look “fuzzy” and “wobbly” whatever you do. You can get a jetstream forecast on the internet like this…

https://www.netweather.tv/charts-and-data/jetstream

Edited by PeterStudz
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A binoviewer helps immensely as well.  I had much better views when both eyes saw the same brightness tonight.

A light green filter like a #56 was helpful when used over my dominant eye to increase the contrast of the GRS and NEB.  It also cut down on the dazzling brightness even with two eyes.  I think it also sharpened the view by cutting out the slightly unfocused red and blue ends of the spectrum due to atmospheric dispersion.

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Sounds like great advice. I sadly don't have a binoviewer. That might have to await Xmas. Still can't wait for another clear night to try higher magnification.

Just had another thought, what about the tube cap. It's two part s9 I could put the outer ring on the scope and cut down the glare. Is that what it's used for?

Thanks all

Edited by uk_friendly_fire
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The two piece tube cap can be used for that, but you'll drastically cut down your potential resolution by masking your aperture.  It can be used to sharpen up the image by making the scope have a longer f-ratio and by making the system unobstructed if it is an off axis opening and you place it between spider vanes.  It can also be used to allow for use of a smaller solar filter.  Try it and see, what's the worst?

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On 28/09/2022 at 08:19, uk_friendly_fire said:

How do I reduce the brightness and see more detail. Is it a matter of increasing magnification or using a filter of some kind of both?

Upping the mag will do the trick. You're currently viewing at 20x, so the image will be very bright. A BST 5mm will put you at 100x which, should help significantly. Fwiw, i've been using an 8mm plossl with a barlow for planetary views in my 600mm length scope.

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On 28/09/2022 at 23:59, uk_friendly_fire said:

Sounds like great advice. I sadly don't have a binoviewer. That might have to await Xmas. Still can't wait for another clear night to try higher magnification.

You won't be able to use a binoviewer with your current scope. The focuser travel is too small and it is not strong enough to cope with the weight of a binoviewer.

I would recommend increasing the magnification to cut down the brightness and increase image scale. If it is the f4.4 114mm Newt that you have I would also recommend using a barlow before the eyepiece. This will increase the focal ratio that the eyepiece "sees" and so would improve the performance of cheaper eyepieces with your scope. 

if you still need a filter I would probably bet something like an ND rather than a polarising filter. I found that the two closely stacked filters of a polarising filter added reflections when observing bright planets.

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Yep, even naked eye Jupiter is dazzlingly bright. I was out a couple of nights back and found it almost painful to look at, but I'm pretty dark. M33 is naked eye when well placed.

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16 minutes ago, uk_friendly_fire said:

Should I use a 5mm bst starguider eyepiece or Barlow plus 10mm bst starguider in preference?

 

Are starguiders considered cheap?



The choice between a 10mm plus 2x Barlow or a 5mm depends on what other eyepieces you have or intend to get?
In the world of eyepieces the Starguiders are relatively cheap. But don’t let that put you off, I’ve personally tried the 5/8/12mm Starguiders and they’re really excellent value for money, super bargain and a significant upgrade from stock eyepieces that come with many new scopes.

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48 minutes ago, uk_friendly_fire said:

Should I use a 5mm bst starguider eyepiece or Barlow plus 10mm bst starguider in preference?

 

Are starguiders considered cheap?

Just to point out, there isn't a 10mm in the Starguider range. Nearest is 8mm or 12mm. Since the focuser isn't the most robust (I have the same scope on the Virtuoso mount) I'd try and avoid a Barlow plus eyepiece due to the weight and length. The 5mm Starguider works well in that scope and gives a decent x100. I've used that exact combination on Jupiter with success. The image is small but sharp and vastly better than the 10mm EP the scope comes with (even if you Barlowed the 10mm).

Ideally you'd want more magnification on Jupiter but you'll be reaching the limitations of the scope, realistically, if you try much more.

The Starguiders are only relatively cheap but they are good value and well-regarded, don't be put off.

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1 hour ago, uk_friendly_fire said:

Should I use a 5mm bst starguider eyepiece or Barlow plus 10mm bst starguider in preference?

 

Are starguiders considered cheap?

Starguiders are some of the, if not the best value for money items <£100. Seriously can’t think of something better, apart from maybe a pair of gloves? Very very good optical quality for £30-35 used is fantastic. I think there is a 5mm going in the classifieds or on Astrobuysell, or at least there was one very recently. 

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All my lenses are BST  Starguiders  except for one Celestron 18mm  X-Cel which I think is quite good. I'm encouraged by your comments on Starguiders so I might invest in a 3.2mm lens. 

This would result in 156x with my SW 114 newt - is this too high a power for it?

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As your retina adjusts to the brightness, more subtle details will gradually emerge. Jupiter is a subject that requires copious time, being comfortable and relaxed and interchanging increasing magnification, enabling your eye and mind to adjust to the brightness.

Moments of good seeing are interspersed with periods of distortion, a haze or thin veil of cloud may assist a little perhaps. I had used a filter a few years ago; TeleVue Planetary Bandmate, certain conditions were favourable and enhanced features, whilst other atmospheric conditions were plainly awful. This season prominent features, such as the Southern Equatorial Belt is rather subtle, at least at the smaller aperture I have so far employed. 

Increasing, pushing the mag and then decreasing magnification, to ascertain what works best on a particular night, is certainly the best approach.   

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1 hour ago, uk_friendly_fire said:

All my lenses are BST  Starguiders  except for one Celestron 18mm  X-Cel which I think is quite good. I'm encouraged by your comments on Starguiders so I might invest in a 3.2mm lens. 

This would result in 156x with my SW 114 newt - is this too high a power for it?

Which of the Starguiders do you have already? And which version of the 114? A short, lightweight Barlow might work better, using a BST you might have already.

In theory, x156 is usable in the scope. I don't own the 3.2mm so can't speak from personal experience but (and based only only on comments I've seen) it's not as well regarded as the 5/8/12/15mm ones. I'm a bit dubious about how much better a view you'd get in reality compared to the 5mm and how often you'd make best use of it. If you have the tabletop Dob version of the 114, you'll also find your target moves pretty quickly across the view, meaning a lot of nudging.

I've used a Baader x2.25 Barlow and a 9mm Nagler (worth more than the scope!) in mine but that combination is fairly lightweight and didn't stress the focuser badly. I wasn't convinced it was clearer than using the BST 5mm alone but it could also have been other factors at play.

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2 hours ago, uk_friendly_fire said:

All my lenses are BST  Starguiders  except for one Celestron 18mm  X-Cel which I think is quite good. I'm encouraged by your comments on Starguiders so I might invest in a 3.2mm lens. 

This would result in 156x with my SW 114 newt - is this too high a power for it?

No, but I found it a bit soft and the 5mm with a 2x barlow or 8mm with a 3x barlow worked better. 

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On 01/10/2022 at 09:45, Ricochet said:

if you still need a filter I would probably bet something like an ND rather than a polarising filter. I found that the two closely stacked filters of a polarising filter added reflections when observing bright planets.

@uk_friendly_fire some variable polarising filters separate. I use the one as shown in the images below.
5addf27ccac70_variablemoonfilter.jpg.e490ce031fc7badb2a139b6d8384c995.jpg1_25filter.jpg.7ec846496e5cb1023cb990df9a7099a4.jpg

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I have a blue filter that I managed to use in earnest for the first time last night. In my 10" dob, Jupiter is very bright with little in the way of detail being visible. I found the filter removed all the glare and gave me a nice clear view of bands and the red spot. Mine is an 80A, but for a smaller telescope the 82A might be better, as I believe it transmits more light.

A basic colour filter for a 1.25" eyepiece is only £9!

I don't particularly like the idea of looking through a colour filter as I like the idea of seeing things as they are. There's no denying the improvement in view, however.

 

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I tried blue and yellow filters last night and although they showed some improvement it was nothing compared to a variable polarising filter in my 200P. It turned a bleached bright cream disc with hard to discern detail into a planet showing two exquisite equatorial belts, visible temperate regions, the GRS and a tack sharp Io with shadow. The amount of light you let in is down to the user too as we all have our own preferences.

I did notice the odd stray reflection but it was very infrequent and nothing that annoyed me.

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On 02/10/2022 at 19:14, wulfrun said:

Which of the Starguiders do you have already? And which version of the 114? A short, lightweight Barlow might work better, using a BST you might have already....

I have the following BST lens 25mm, 18mm, 15mm, 12mm, 8mm, & 5mm and short X2 Barlow.

The newt is a blue painted pre-owned eBay SW114 probably parabolic. It has a hopeless focuser which doesn't stop when racking out.

Nevertheless I was blown away by last night's view of Jupiter @ 10.30 pm bst. Using the suggestion in this thread I used a higher power lens,  an 8mm lens with a x2 Barlow and saw for the 1st time in my life the cloud bands and 4 moons. I couldn't see the red spot but the jubilation of seeing the cloud band's using a very sensitive focus was fantastic. 

I WANT MORE OF THIS.

I can't thank you all enough for the help you have given me in this thread. I'm over 60 years young and this has made me feel there is much more to accomplish and quite a bit emotional too.

Thank you all

 

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27 minutes ago, uk_friendly_fire said:

I have the following BST lens 25mm, 18mm, 15mm, 12mm, 8mm, & 5mm and short X2 Barlow.

The newt is a blue painted pre-owned eBay SW114 probably parabolic. It has a hopeless focuser which doesn't stop when racking out.

Nevertheless I was blown away by last night's view of Jupiter @ 10.30 pm bst. Using the suggestion in this thread I used a higher power lens,  an 8mm lens with a x2 Barlow and saw for the 1st time in my life the cloud bands and 4 moons. I couldn't see the red spot but the jubilation of seeing the cloud band's using a very sensitive focus was fantastic. 

I WANT MORE OF THIS.

I can't thank you all enough for the help you have given me in this thread. I'm over 60 years young and this has made me feel there is much more to accomplish and quite a bit emotional too.

Thank you all

 

Excellent news, really glad you got some good views. I’m sure with further observations you will start to pick out more detail. Next stop Saturn? 👍

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Just to throw another filter into the range of options, I have just bought a Baader Contrast Booster specifically for planetary work. It's an interesting one: I was expecting a dimming or colour change, but that just didn't happen on Jupiter. There was a subtle but marked increase in detail. I haven't used it on Saturn or Mars yet.

All you people complaining about Jupiter being too bright, remember it's at its closest to us for 70-odd years. Consider yourselves lucky! 😄 No doubt in a few years, people will be complaining that it's too dim.....

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