17 replies to this topic

[Vilmos93]

Hello! 

 

I am a beginner user of a 254/1200 Skywatcher newtonian telescope. I have been using this telescope for only a year. My first planetary season was last year and I started visual observing with Saturn.  It was soooo amazing.  The next target was Jupiter and this is where the trouble started. It was too bright to see the nice colours. My first and last idea was to use a moon filter. This is the filter I used:  https://tavcso.hu/te.../szurok_neutral. With this filter it was slightly better but it made it too dark and grey this way. 

 

Do you have any ideas about what filter to use on Jupiter for visual observation? 

 

Thank You!

Clear Skies!

Vilmos

[rustynpp]

Hi Vilmos,

 

Try turning on the lights around your observing area, if possible. Reducing your pupil size will help turn down the glare from brights planets and the moon.

 

Cheers,

Nick

[Notdarkenough]

I sometimes use my Baader Neodymium Moon & Skyglow filter for Mars, Jupiter and Saturn. Mostly, it does help with contrast, sometimes no filter is best.

 

Another trick is to increase your ambient lighting. Planetary observing is best when in color, and you need light to keep your eyes in the 'color' mode. So, I often have a small table lamp nearby to keep my eyes from 'dark adaptation'. In this regard, Planetary Observation is exact opposite of DSO Observation, where you see the faint fuzzies in monochrome.

[JohnBear]

Good questions, Vilmos. 

 

It may help us to  help you if you can fill out your CN  profile information a bit more such as your location (I assume Europe) and a list of your primary astronomy equipment, including eyepieces. 

 

I  find that a 25% neutral density filter is often much more useful that the usual 13%.

you will also find the using higher magnifications will decrease the amount of light entering your eye - but excessive magnification (for the seeing conditions) can also provide more inferior image than lower magnification views. 

 

You already have a couple of good suggestions about using ambient light to adjust you pupils for viewing brighter objects - but be aware that it mat take a half hour (or more) for you eyes to readjust for good viewing of darker objects. 

 

I would also suggest joining a local astronomy club (if you are not already a member) to get familiar with the wide variety of astronomy equipment that is available - and for local help.

 

Clear skies!

[RedLionNJ]

Try a slightly larger magnification, if the seeing permits. That will mute the brightness per unit area.

[Noto]

I had the same problem with my Orion 8" XT8 Plus (203/1200). I tried to use the same ND96-0.9 moon filter (13%) that you have, but also found it was too dark.

 

However, I purchased an Orion Variable Polarizing Filter, which has a range between 1-40%. 

 

13% was too much, but with the variable filter, I was able to dial-it down until I found a pleasurable view (probably somewhere between 5-10%).

 

You can check out the Celestron Variable Polarising Filter on the same Hungarian website you linked.

 

Some of the color filters will help in dialing down the brightness, especially if you stack them. However, that's a whole different ball of wax...

 

Wish you the best - clear skies!

[vtornado]

What eyepiece were you using?

 

If you are using medium power for Jupiter, follow rusty's advice. put a white light 

around your observing area.

 

If you are using high power 200x or more, I have never had a problem with glare,

and start wishing things were brighter.

 

Do not use a moon filter.  First it is probably not flat.  meaning it will introduce optical

abberations.  Second you need the light to see details.

 

A moon and skyglow filter (different than a moon filter) helps boost contrast

on Jupiter's belts.  It is not OH WOW! better, but it helps.  I have a cheapie

(vite branded) filter.  Maybe a Baader would be better, but it is too expensive

to try.

 

 

Then there are observing tips in general.

 

Your scope has to be collimated very well.  Do a star test to make sure.

 

Your scope has to be cooled very well.  A 10 inch takes a long time to cool.

If you defocus on the planet and it looks like "flashing" or "ants" crawling

across the image, your scope in not cooled or seeing is poor.  The edge

of the moon can be used to test cooling/seeing too.  If it is shimmering

somthing is a foot.

 

If you have a fan use it.  If that fan introduces vibration, shut it off when viewing.

 

Don't view over warm objects like a driveway, street, roof etc.

 

Check seeing conditions, but watching the twinkle rate of a bright star near your target.

Seeing can change in a moment, you need to watch for a long time.  Sometimes

an hour of "soft" views can clear up in a second.  and go right back to fuzzy in another

second.  On nights like this a comfortable eyepiece beats a uncoforable one.

 

If possible view the planet at the meridian since this is the highest it will climb in the

night.

[Noto]

 

Do not use a moon filter.  First it is probably not flat.  meaning it will introduce optical

abberations.  Second you need the light to see details.

 

Have you used a variable polarizing filter?  It's my go-to for Jupiter. No aberrations for me, the colors look just fine, and I can easily make out the various bands. But as I said, I was on the lower end of the filter (I honestly do not know the comparison of the ND moon filters vs the polarizing filters; it's it's the same "glass" and such).

 

When it comes to the surrounding light, I feel like I'm already in a mall parking lot (tons of security lights in my complex). However, I have never noticed it to help me reduce the "moon-like" glare I get with Jupiter (if I want dark-adapted eyes, I have to hide behind my building for at least 30-min).

[KWB]

Try a slightly larger magnification, if the seeing permits. That will mute the brightness per unit area.

 

Welcome to the forum.

 

You have plenty of aperture for spotting Jovian detail. I do not use filters with a 10 inch scope or an 80mm scope for planetary viewing. I once tried an 82A filter(73% transmission) when I started out in this hobby and the results were basically nil as to a benefit to me seeing any extra detail. I don't uses moon filters when viewing the lunar surface, either.

 

Another thing to remember, if you are trying to observe the Great Red Spot. Jupiter spins on it's axis once every 9.5 hours so it may not be on the right side of the planet at the time you are trying to detect it.

 

Hang in there, you have the right telescope for the job. 

[rhetfield]

My main filter for dimming the moon and planets is a variable polarizer.  With Jupiter, my real preference is to look at it at sunrise or sunset when it is high.  Much less glare and better opportunity for detail.  Same thing with Mars when it gets close.  I don't trust having a couple extra pieces of glass of questionable build quality and fingerprint count to give me the best detail..

[sevenofnine]

My technique for viewing Jupiter is simple. Instead of using my red flashlight for setting up the scope, I use the white light flashlight. I turn it on occasionally to keep my pupils from dark adapting 

 

p.s. The old fashioned 80A blue filter works for planetary detail but casts a bluish tint to the planet.

[epee]

As others have said, this is a case where avoiding dark-adaption helps.

 

I use a single, not variable, polarizer and a "Moon and Skyglow" filter.

 

Continuing to track the planet into the brightening morning sky can be beneficial as well.

[Napp]

Don't forget that there will be a Mars opposition late this year.  You think Jupiter is a challenge - just wait for Mars.  Other than the polar caps most all Martian features are very subtle.  For Mars and Jupiter I like either the Baader Moon and Skyglow Filter or the Baader Contrast Booster.  I like these filters becasue they don't change the colors and do increase contrast.  I keep both handy when observing either Mars or Jupiter.  As noted in an earlier post don't expect anything more than subtle increases in contrast.  Also as posted several times above you need to keep the color receptors of the eye active.  Twilight is a wonderful time for planetary observing for that reason.  This is a type of observing where light pollution can actually help.  I do most of my planetary observing at home.  There are enough lights around I have no trouble keeping my color receptors active.  

 

For planetary observing you have to be patient at the eyepiece.  The steadiness of earth's atmosphere above you (seeing) determines what your scope can show.  Seeing can change quickly for the small patch of sky your are looking through.  Features can suddenly snap into clear focus for seconds or minutes and then blur again.  Choose magnifications to match seeing conditions.  However, experienced observeres may deliberately use too much power waiting for those brief periods when seeing will suddenly become good enough to support higher magnifications.  Of course you spend a lot of time with a blurry image that way.  It takes patience.

 

Someone mentioned above that Jupiter's Great Red Spot is only visible when turned toward us.  It's more limited than that.  The GRS is usually only visible when near transit away from Jupiter's horizon.  To make it more difficult the GRS is a low contrast feature.  Many planetarium apps incuding Sky Safari and Stellarium will show when the GRS will be transiting.  Sky & Telescope has a suite of tools that show GRS transit times, moon locations for Jupiter, Saturn, Uranus and Neptune, and what face/features of Mars are showing when.  You can find these tools at https://skyandtelesc...watching-tools/

[JohnBear]

Probably one of the easier and more interesting (and fun - for me anyway) Jupiter observations have  been the moon shadow transits.  The shadows of a transiting moon are fairly easy to spot as the race across Jupiter's clouds. I have yet to get a good view of the GRS however.

 

Until last year, I had only seen Mars as a tiny red-orange dot in my telescopes, But when it reached closest opposition in 2020 I viewed it with a binoviewer a 6SE that I had recently purchased and tuned up. It definitely looked bigger that the dots I was used to but any features were almost nil. I tried a couple of LP and polarized filters which really did not help at all.

 

Then, by chance, I used dumb old plain red filter that was in the box - and BOING, the larger land features suddenly stood out, and it definitely looked like a "real planet" (instead of a dull red ball) - especially with the binoviewer that gives the viewer an immersive 3D effect.  I'm looking forward to Mars opposition this year, and exploring it with Big Bubba, my 12; dob and filter wheel..

 

The one thing that I have found to really improve planetary viewing is simply very clear, Calm, and dark skies. They don't occur all that often, but when they do - Oh, Boy! They can make your telescope optic chain exceed your expectations. 

[Vilmos93]

Hello!

 

Thank You for all the helpful questions and recommendations!

 

As more of you recommended, I will try an ambiente lighting while observing with my red-white headlight, and get a moon and a skyglow filter!
Thank You for the idea! I will consider buying a Celestron Variable Polarising Filter.

 

Yes, I live in the EU, and I have the following equipments so far:

 

8-24mm Celestron zoom eyepiece (The most of the time I use this with the barlow)

 

3.2mm skywatcher planetary

 

6mm skywatcher goldline

 

15mm lacerta

 

24mm skywatcher

 

and a 2x barlow.

 

Beside of these I have 2 kind of moon filters for visual observing, and an OIII filter.

 

Thank You for your help!

Vilmos 

[epee]

You can cut costs buying two single polarizers rather than a "variable". The most convenient way to produce a variable polarizer is to place a 2" polarizer in your 1.25 to 2" adapter and then a 1.25" polarizer in you eyepiece. Then, rather than having to remove the eyepiece each time you want to adjust the darkness of the polarizer, you just rotate your eyepiece a little.

However, a pair of regular polarizers screwed together makes one variable polarizer. Just make sure you buy polarizers threaded on both sides.

Edited by epee, 18 May 2022 - 04:33 PM.

[vtornado]

Have you used a variable polarizing filter?  It's my go-to for Jupiter. No aberrations for me, the colors look just fine, and I can easily make out the various bands. But as I said, I was on the lower end of the filter (I honestly do not know the comparison of the ND moon filters vs the polarizing filters; it's it's the same "glass" and such).

 

When it comes to the surrounding light, I feel like I'm already in a mall parking lot (tons of security lights in my complex). However, I have never noticed it to help me reduce the "moon-like" glare I get with Jupiter (if I want dark-adapted eyes, I have to hide behind my building for at least 30-min).

If this is addressed to me, then I have tried the following observations.

 

Variable polarizer set on lowest setting on Venus .... allows me to see some cloud formations, although they are very subtle and I may be getting percival lowell if you know what I mean.

 

Variable polarizer vs ND filter on the moon.  I see no difference if the polarizer is set to the same darkness as the ND filter.  Thus I see polarization adds no enhancement over simple dimming of the ND.

 

Interjection of errors ...  I think this would be very hard to determine.  Viewing Jupiter

one is looking for the most small, low contrast, dim features, for example seeing festoons or ovals.  If this low level detail is "erased" by errors in the optical flatness of the filter,

it would be hard to figure out whether it is the loss of light or some imperfection.

Mabye ... a planetary camera can be used, and turn up the gain when the filter is in.

 

Next time the moon is out I can try counting craterlets in plato or clavius to see

how the filter may distort things.   Although viewing this fine detail may also

be affected by the loss of light.

 

Consider that some folks spend hundreds of dollars on a simple planetary eyepiece

because they are trying to pick up that last 1%.  To put a $20 ND filter in the

optical path may lose 5%. 

 

According to the baader website, their filter is AR coated, and finely optical polished.

The Celestron filter, and I assume other $20 filters make no such claims

Edited by vtornado, 18 May 2022 - 04:59 PM.

[GGK]

If I’m using a filter on Jupiter, it’s usually a Baader Contrast Booster, a Contrast Booster combined with a pale blue 82A or light yellow #8, or a light red #23. It really depends on what features I’m trying to highlight. None of the effects are major - just very subtle improvement if anything. No filter or just a Contrast Booster is my most common practice.

Like JohnBear mentioned above, I get just as much entertainment looking at Jupiter’s moon shadows or going extra wide to see as many moons as possible.

Like others have said, having some low-level ambient white light behind me restricts my pupils and helps if Jupiter’s glare is bad.

Gary