Expected size of Saturn.

[Daz Type-R]

Hi all.

I was out for 4 hrs last Saturday night and it was only the 3rd time out with my scope since purchase, so still getting the hang of it

Managed to spot the M42 nebula (allthough the "cloud" was very faint), checked out a few other bits of interest untill about 23:00 when Saturn was high enough for me to see over the trees at the bottom of my garden.

Now with the scope that I have (see sig) what size would you expect Saturn to be with the following ep's, standard 25mm and 10mm?

I found it very easily but once focused up it was about the size of this (see smiley to the right)

I could make out the rings, a few specks of light (which I presumed to be moons) but thats it, no cassini (sp?) division, no detail etc.

Could this be down to lp, could it be down to my stock ep's being not so good, or could the seeing conditions last Saturday not of been great?

Also, my scope is collimated!

Just wondering what to expect from my scope?

Cheers for any comments guys and gals.

Regards,

Daz.

[Kai]

I would of thought a combination of the above plus the need for a bit more focal length , did you get a barlow with your scope ?

[Steep]

I have thought that a ND filter might be useful, Saturn was very bright for me the other night with all detail washed out.

[junior]

I have found that setting up the eye pieces in Stellarium gives a fairly ok inidication of what you can expect to see with regards to the plants, not so much DSO's though.

[Peter Drew]

I agree with Kai, even with a 200mm scope the Cassini Division can be difficult in so-so conditions. I find that I need more magnification than the around 125x that your 10mm eyepiece will give. Theoretically, the Cassini Division should be near the limit of resolution for a 200mm as it is only .5 arc seconds wide, however, because it is a line rather than a spot it's much easier than it should be, I seem to remember that it was discovered with a scope aroud 70mm. The other issue you raise, and one that comes up regularly with those new to using telescopes, namely the size of objects as seen in the eyepiece. Both Saturn and jupiter will appear larger than the full Moon as seen with the naked eye if 125x magnification is used on these planets, it never looks like this as you rarely get the chance to compare directly. If you look at the full Moon through an 1.25" adaptor with no optics in it you will be surprised just how small the Moon looks. .

[Rufusgj]

I always use this site to check what size things should appear in the eye piece...

http://www.12dstring.me.uk/fov.htm

I think it may well be a fellow SGL member who created it so I'm not taking the credit - but thanks anyway!

Simon

[PeterM]

That sounds about right to me size-wise. You're going to need higher mag (maybe a 6mm EP) to get the best out of Saturn. There is far, far less detail on Saturn compared to Jupiter so it doesn't sound like there's anything wrong with your kit. It's commonly a very bright disc with a ring, sometimes you see more in the rings, sometimes not.

[The Bat]

I would definitely use a barlow. I find Saturn best at about 160x. Under reasonably good seeing conditions and with the rings as they are now, I can see the Cassini division, but it comes and goes with the atmospheric turbulence. I have seen up to 5 moons, depending on where they are placed. On the surface I can make out one or two cloud bands, but not a lot else.

Persevere with it; the more you look, the more you will see.

Rachel

[Stephen]

Daz, with the same scope and the webcam I was able to get this

http://stargazerslounge.com/imaging-planetary/132019-2011-02-27-first-view-saturn.html

But it's still tiny Using my TMB 6mm it was about the same size, maybe a little smaller to be fair. You need to get some serious barlowing going on with the scope to make it "ample" size but conditions are probably going to stop you doing that.

[junior]

Will be nice when we get some clear weather so i can have a look for myself.

[Capricorn]

The simple answer to the question is: Small.

OK, Saturn is bigger then Earth but it is a damn long way away.

The damn long way away wins.

[hamiclar01]

If it's any consolation Daz, I get the same sized Saturn as you via the eyepiece. haven't used a barlow, yet.

[tom33pr]

I always use this site to check what size things should appear in the eye piece...

http://www.12dstring.me.uk/fov.htm

I think it may well be a fellow SGL member who created it so I'm not taking the credit - but thanks anyway!

Simon

That website looked intriguing till I decided what I'm supposed to be getting with the combination of my SE 130p/Phillips SPC900 when viewing M42...

It's a bit of a joke, isn't it?

CropperCapture[20].Bmp

[Stephen]

That website looked intriguing till I decided what I'm supposed to be getting with the combination of my SE 130p/Phillips SPC900 when viewing M42...

It's a bit of a joke, isn't it?

It's not showing you what you are expected to get, it's showing you expected size of what you are going to get The number of images to cover every possible combination would be impossible to gather, so it takes a high res one and scales as per the setup specified.

So long as you remember that, it works fine.

[tom33pr]

It's not showing you what you are expected to get, it's showing you expected size of what you are going to get The number of images to cover every possible combination would be impossible to gather, so it takes a high res one and scales as per the setup specified.

So long as you remember that, it works fine.

Fair enough!

Thanks.