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How many bands on Saturn can you see in your 3" and 4" apochromat.

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#1 Magnetic Field

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Posted 18 May 2019 - 02:14 PM

Before anyone lobs stones at me: this is not a confrontational post. And this is not a post refractor vs reflector.

 

 

I observed Saturn 2 weeks ago low on the horizon under bad seeing with my Vixen VMC 110L (magnifications: 130x, 170x and 210x).

 

I saw 1 equatorial band (again bad seeing and low at the horizon).

 

 

Someone made a sketch of hot new Saturn with his 40cm Dall-Kirkham reflector:

 

https://www.cloudyni...m/#entry9369266

 

 

Does your 3" or 4" apo ever show more than 1 or 2 bands on Saturn?


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#2 Astrojensen

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Posted 18 May 2019 - 02:20 PM

Hmm. It's been quite a few years since Saturn had a reasonable altitude from my part of the woods, but I did observe it frequently way back in the late 1990'ies, when it was very high in the sky from northern latitudes. Here's a drawing from observations made on December 1st, 1998, with my 85mm Zeiss A apochromat:

 

gallery_55742_324_1407446967_23156.jpg

 

It's obvious that the equatorial band was split in two, but apart from that, I didn't see any other bands and I don't think I've ever seen more in a small scope. 

 

 

Clear skies!
Thomas, Denmark


Edited by Astrojensen, 18 May 2019 - 02:31 PM.

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#3 Astroman007

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Posted 18 May 2019 - 02:36 PM

Does your 3" or 4" apo ever show more than 1 or 2 bands on Saturn?

Hmm, good question. I shall find out after I get my much-desired 4.7mm Ethos-SX eyepiece, and pair it up with my TV-85. I only have the 20mm Plossl that came with the scope, which is not nearly enough magnification for teasing out the bands of Saturn, though it's enough for an impressive low power view of the Moon and should be enough to show a satisfactory yet small image of Saturn and its rings.


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#4 Magnetic Field

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Posted 18 May 2019 - 02:41 PM

Hmm. It's been quite a few years since Saturn had a reasonable altitude from my part of the woods, but I did observe it frequently way back in the late 1990'ies, when it was very high in the sky from northern latitudes. Here's a drawing from observations made on December 1st, 1998, with my 85mm Zeiss A apochromat:

 

gallery_55742_324_1407446967_23156.jpg

 

It's obvious that the equatorial band was split in two, but apart from that, I didn't see any other bands and I don't think I've ever seen more in a small scope. 

 

 

Clear skies!
Thomas, Denmark

Long time ago in the early 90s when I was a failed teenage wanna-be break-dancer  I owned a 4" f/10 Vixen achromat.

 

The most I could ever see on Saturn were 2 bands (but even then I always found it hard to split them).***

 

 

***Cassini, the shadow of the disc on the rings and the shadow of the rings on the disc and maybe some shadowing on the poles are always visible in a small telescope.


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#5 Astrojensen

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Posted 18 May 2019 - 02:48 PM

***Cassini, the shadow of the disc on the rings and the shadow of the rings on the disc and maybe some shadowing on the poles are always visible in a small telescope.

The shadows of the globe on the rings and the shadows of the rings on the globe aren't always visible, but depend on Saturn's position relative to Earth and the Sun (I guess you know, I just wanted to point it out to those that might not).

 

On my drawing, the thin, dark band inside the B ring, is NOT the shadow of the rings on the globe, it's actually the C ring seen against the globe. The shadow of the ring on the globe is seen on the outside of the ring, against the globe. 

 

 

Clear skies!
Thomas, Denmark


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#6 Magnetic Field

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Posted 18 May 2019 - 02:57 PM

The shadows of the globe on the rings and the shadows of the rings on the globe aren't always visible, but depend on Saturn's position relative to Earth and the Sun (I guess you know, I just wanted to point it out to those that might not).

 

On my drawing, the thin, dark band inside the B ring, is NOT the shadow of the rings on the globe, it's actually the C ring seen against the globe. The shadow of the ring on the globe is seen on the outside of the ring, against the globe. 

 

 

Clear skies!
Thomas, Denmark

 

I know. All I wanted to say: even under mediocre seeing Cassini is always easy.

 

But your other remark is interesting and needs further elaboration. I always thought the black strip running between the ring and disc is the shadow of the edge of the inside ring (I often see this feature in my Vixen VMC 110L easily as well, e.g last summer in August 2018).

 

A learned a new thing. Very interesting indeed that this is related to the C-ring.


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#7 Astrojensen

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Posted 18 May 2019 - 03:02 PM

Just used Stellarium to reenact the observation. I also identified the "stars" I had drawn on the small sketch to the left: It's Titan (identified in the sketch) Rhea (right), Tethys ( left, closest to Saturn) and Dione.

 

I can't remember it now, but it must have been a stunningly beautiful evening. Jupiter was in the western sky, all four satellites visible, the nearly full Moon was high in the east, quite close to Saturn and Orion had just risen above the eastern horizon. 

 

 

Clear skies!

Thomas, Denmark 


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#8 Astrojensen

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Posted 18 May 2019 - 03:09 PM

I know. All I wanted to say: even under mediocre seeing Cassini is always easy.

 

But your other remark is interesting and needs further elaboration. I always thought the black strip running between the ring and disc is the shadow of the edge of the inside ring (I often see this feature in my Vixen VMC 110L easily as well, e.g last summer in August 2018).

 

A learned a new thing. Very interesting indeed that this is related to the C-ring.

It isn't just merely related to the C ring, it IS the C ring! 

 

And a lot of people mistake it for the shadow of the rings, because it is so easy to see, while the C ring in the ansae is very difficult to see in a small scope. 

 

Confusingly, the shadow of the rings CAN sometimes be on the inside of the rings, but that happens relatively rarely. Whether this is the case depends on the complex interaction between the positions of Saturn, Earth and the Sun and the tilt of the orbital planes. If in doubt, it's best to check a reliable and accurate source, such as Stellarium, Sky and Telescope, etc. 

 

 

Clear skies!
Thomas, Denmark


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#9 Jeff B

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Posted 18 May 2019 - 03:38 PM

"Does your 3" or 4" apo ever show more than 1 or 2 bands on Saturn?"

 

Actually none of my scopes shows any bands at all on Saturn.  I thought I might be able to resolve at least a drum kit but nope.


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#10 Sasa

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Posted 18 May 2019 - 03:47 PM

I can see in my 82mm refractor basically the same what Thomas described. Equatorial belt shows double structure (sometimes visible even in 63mm Tementor), plus there is darkening around north pole with subtle changes of color in between the polar region and north pole. Sometimes I can see  a hint of some additional belt. If conditions are good, I can also feel the presence of C ring:

 

Saturn_20180820_1900UT.jpg


Edited by Sasa, 18 May 2019 - 03:48 PM.

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#11 Tyson M

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Posted 18 May 2019 - 03:53 PM

"Does your 3" or 4" apo ever show more than 1 or 2 bands on Saturn?"

 

Actually none of my scopes shows any bands at all on Saturn.  I thought I might be able to resolve at least a drum kit but nope.

Ba Dum Tss.jpg


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#12 Magnetic Field

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Posted 18 May 2019 - 03:57 PM

I can see in my 82mm refractor basically the same what Thomas described. Equatorial belt shows double structure (sometimes visible even in 63mm Tementor), plus there is darkening around north pole with subtle changes of color in between the polar region and north pole. Sometimes I can see  a hint of some additional belt. If conditions are good, I can also feel the presence of C ring:

 

Saturn_20180820_1900UT.jpg

 

I must say last year in August 2018 with my Vixen VMC 110L I wasn't sure if I saw 1 or 2 bands.

 

At that time my max magnification was 138x (I only recently acquired oculars for 170x and 207x).



#13 Asbytec

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Posted 18 May 2019 - 04:09 PM

"Does your 3" or 4" apo ever show more than 1 or 2 bands on Saturn?"

 

There are actually two primary equatorial belts, one is often hidden by the tilt of the rings. But, if the tilt is just right, we should be able to see part of it as David Gray's sketch shows.. The C ring is interesting, eerily transparent, if it shows beyond the globe near the ansae. (Reading above, I may have mistaken it for the shadow of the rings.) Another feature to look for is the brighter rings bordering both sides of Cassini. The Enke minimum is also available for viewing, and either polar cap visible should show some darkening. The extent of Cassini division can be challenging, easier on the ansae. 


Edited by Asbytec, 18 May 2019 - 04:11 PM.


#14 David Gray

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Posted 18 May 2019 - 04:51 PM

There are actually two primary equatorial belts, one is often hidden by the tilt of the rings. But, if the tilt is just right, we should be able to see part of it as David Gray's sketch shows.

Sorry Norme I have not depicted the SEB; well only by proxy of it possibly contributing to the tone of semi-transparent Ring C crossing the globe: Cm (not to be confused with CM: Central Meridian); where its usual latitude currently lays behind.

 

The shading in mid-EZ north of Cm is the EB (Equatorial Band).   It will likely be 2023 before we get sight of the SEB(N) appearing south of the closing rings – we have to remember that the globe is tilting in concert with the ring system thus hiding the SEB for some time yet!

 

Actually when the Ring Shadow shows within the ring (not that rare) it is always within/behind Cm.

 

Dave.

SAT 2019 May 16 III.jpg


Edited by David Gray, 18 May 2019 - 04:56 PM.

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#15 Asbytec

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Posted 18 May 2019 - 05:25 PM

Okay, David, thanks for the clarification. It's been a while, I may have mistaken the Cm for an EQ belt, too. Need to go back and check my notes. 

 

Edit: After checking, Saturn was not as titled as it is today, I caught something below the ring not inside it.

 

I did not record the EQ belt being split, just a dark belt separated from the polar region. Hmmm...not unlike these images. 

https://www.cloudyni...-1430762609.png

https://whyevolution...glish.jpg?w=420

 

Well, there is a soft belt between the EQ and polar region, but not nearly strong enough to look like the EQ belt is split. Not to my eye. One is much more prominent than the other. But, it's easy to see why it may appear split if one can really see than softer belt.

https://www.cloudyni...-1465417387.jpg

 

A great small bore thread to browse.

https://www.cloudyni...-less/?hl= bore


Edited by Asbytec, 18 May 2019 - 06:38 PM.

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#16 BillP

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Posted 18 May 2019 - 08:03 PM

Hmmm.  Interesting.  I never count the bands on Saturn when I observe it.  Usually observe it in my 4" Apo.  When seeing is steady seeing the complete Cassini is easy, A-B-C Rings, several bands (i.e., more than 1 or 2), North Polar Region, darker coloration of the Polar Hexagon is often easy, shadow of the rings on the orb when there.  If seeing really good then the Enke Minima shows, although difficult in the 4" Apo it is quite easy in the 6" Apo.


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#17 starman876

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Posted 18 May 2019 - 10:07 PM

You need a scope with really good contrast to see the bands.  That means a really smooth good figure.   


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#18 barbie

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Posted 18 May 2019 - 10:17 PM

I've seen several(never really counted them) bands on Saturn's globe with my 3" and 4" apos.  Cassini  is easy all the way around and jet black.  Shadow of globe on rings(when visible) and darkening areas in the rings(when seeing is at its best for me) in my 4" apo.  The "Crepe" ring is also usually visible as well under excellent seeing conditions.



#19 25585

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Posted 19 May 2019 - 04:38 AM

Anyone seen the Encke Gap/Pan's Gap?



#20 Magnetic Field

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Posted 19 May 2019 - 06:34 AM

Anyone seen the Encke Gap/Pan's Gap?

 

With a 3" or 4" (any type of telescope).



#21 Magnetic Field

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Posted 19 May 2019 - 06:41 AM

I've seen several(never really counted them) bands on Saturn's globe with my 3" and 4" apos.  Cassini  is easy all the way around and jet black.  Shadow of globe on rings(when visible) and darkening areas in the rings(when seeing is at its best for me) in my 4" apo.  The "Crepe" ring is also usually visible as well under excellent seeing conditions.

When you say you have seen several bands (>3?) in your 3" and 4" apochromats.***

 

Does that mean your view of Saturn is the impressive one I showed of the other mate in my link in my commencing post of this very thread?

 

***If this is so, out of interest: what telescopes do you have from which brands and at what f-ratio.



#22 barbie

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Posted 19 May 2019 - 12:25 PM

When you say you have seen several bands (>3?) in your 3" and 4" apochromats.***

 

Does that mean your view of Saturn is the impressive one I showed of the other mate in my link in my commencing post of this very thread?

 

***If this is so, out of interest: what telescopes do you have from which brands and at what f-ratio.

Yes and check out my signature line !



#23 Magnetic Field

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Posted 19 May 2019 - 12:35 PM

Yes and check out my signature line !

This now calls for introspection because I cannot* believe it.

 

A 4" (I picked your Takahashi FC100DF) shows as much as the 40cm Dall-Kirkam?

 

2 things come to mind:

 

1. You have got excellent seeing conditions in Ohio. 

2. And this is more a question for the Dall-Kirkham owner: why the 40cm Dall-Kirkam if I can get the fantastic Saturn view with a 4" apochromat.

 

What would a 5" apochromat show?

 

Have you observed Saturn recently (the link and Dall-Kirkham based sketch showed Saturn from the UK as of 3 or 4 days ago)? Ohio (if it is the one on google maps) is much lower than the UK so Saturn is higher in your sky but I don't think this would explain it.

 

***Edit: I don't believe it. No way.


Edited by Magnetic Field, 19 May 2019 - 12:38 PM.


#24 barbie

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Posted 19 May 2019 - 12:54 PM

I don't really care what you believe! I get very detailed views of Saturn through my apos that punch above their aperture class but my seeing has to be able to support those views. This does happen, but rarely. Granted, I don't get the same image size(you never elaborated upon that) but I do see the details! I detect much jealousy in your comments!!


Edited by barbie, 19 May 2019 - 01:27 PM.

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#25 David Gray

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Posted 19 May 2019 - 01:34 PM

Two things – not wanting/asking to get embroiled here....but feel cautioned to keep a wary eye...

 

Firstly a decent 6-8” scope of any regular sort would get most of the detail rendered there.......as I tend to seek discrete hues on the planet (light grasp figures there) it’s often at the cost of finer detail.

 

I have a long practiced eye and my credentials are acknowledged by very seasoned and highly skeptical-inclined BAA Section Directors – in this age of imagery they still come to me for stuff.  I can sketch what I see with recognized accuracy (BAA) so with me its illustrations not words – show not blow........ needs only be an annotated line sketch – nothing fancy....

 

Second whilst I recorded steady Seeing and good Transparency; at the 13º altitude I’m looking through a long path length of particulates as compared to higher.  Thus there is another factor there that affects the crispness of the planet regardless of steadiness.  The view I got the other morning I might count on another couple of times rest of the apparition at the enduring lo-altitude– tho’ have been a little luckier than that recent ones.   As I said in my thread systematic observing is virtually out – maybe till the mid 2020s.

 

That D-K (see attached) has served me well these 4+ decades and I use for much more than planets.  I have never looked through a similar sized refractor but some visiting seasoned/eminent-even have and they all comment on the refractor-like views but without the chromatic issues...

 

During the 1990s apparitions I was getting upwards of 150 transit timings per apparition (CMTs) of features (some quite delicate/fleeting) on Saturn.  Recent years Richard McKim analysed these along with others including imagers and got good zonal rotation periods for many of them.

 

Those reports are here.... https://www.britastro.org/node/13307

 

Here is another recent thread with my old 3” refractor used... https://www.cloudyni...jupiter-saturn/

 

DG.

DK and DGray.jpg


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