Magnification for Cassini Division

[Russty]

Just a quick question, I was out last night using my 200p for the first time and was looking at Saturn I managed to use a maximum of a 7.5mm Plossl which I believe gave me a mag of 133 (ish). At that magnification it was resolved well but (any higher and it started not to focus up) I could not make out the Cassini Division. So the question is how much magnification do I need to use to see the Cassini Division in an 8" newt? Or is that like asking how long is a piece of string? Will the seeing, atmospheric conditions and position of Saturn all be factors.

Cheers.. Russ

[Scott]

I would think that e.p. would do it. I may be wrong be I'm sure I've seen it with the bog standard skywatcher 10mm ep (I'm sure I'll be corrected if this is unlikely .my guess is that the seeing just wasn't up to it. also, check your collimation. (every bit helps)

[alanjgreen]

Cassini was coming and going last night @x120 mag in my C8 SCT

It was more long lasting @x146

Seeing was hit & miss though!

Alan

[Peter Drew]

Seeing seems to be the most common factor, enough magnification to prevent the brightness of the rings from swamping the Cassini Division usually does the trick under good conditions.

[Timbo]

Whilst I'm not experienced enough to comment I would just like to add that I was thinking your same question Russty last night. I was looking only at Saturn last night with my smaller Skymax 127.

I too maxed out my mag with my Orion Barlow and 12mm Excel ep which I think was effectively 6mm. Whilst the image was larger, it was blurred and not as bright.

I'm not out to hijack your thread! Just join you in sympathy!

Perhaps the seeing was not as good as I thought.

Tim

[Timbo]

Sorry, I forgot to comment on the jist of your question Russty: -

I couldn't see the division last night either (!), that was at x125 with a 12mm and thinking that by barlowing the 12mm I might do so, ended with a larger but blurred Saturn ans still no division.

Perhaps though, my 127 isn't big enough! or perhaps it is and the seeing was wobbly I'm not sure either way.

T

[Schorhr]

Probably seeing.

I had more luck with a 2.5mm Planetary (260x), could only spot it a few times, but sometimes it's so blurry and wobbley at that magnification that it's just no use at all...

[cotterless45]

Probably seeing and your collimation has got to be spot on. We had Cassini all the way round, the shadow of the rings, colour to the surface markings ,the Encke and the inner C ring ( Crepe) at x240 last night.

This was with a 5mm Bst in an f6 10" Lightbridge. You should be able to pick out the Cassini from x100.

Last night the seeing on bright objects was superb, but very poor on faint objects.

It's also helpful to relax your eye and not strain and squint.

Saturn is a wonderful target and we spent a long time transfixed,

Nick.

[Scooot]

I had quite a good view of it last night at 240 mag. 10mm barlowed. It was quite high at the time and I think the seeing was quite good. I could also just make it out without the barlow at 120 mag. I was also using the EQ platform so it was fairly steady. I think it just depends on the conditions.

[Rhys Hardwick]

I have seen the Cassini division with my 130p and 10mm with Barlow (130x), so I imagine you'll be fine! It takes time to make out, I didn't see it on my first look. Keep on going, I'm sure you'll see it.

[Russty]

Thanks all for the replies, collimation was good, so from what you are all saying I guess its the seeing that's the problem that and my inexperience at viewing objects through a scope. Well I'll keep trying.

[Druid]

Cassini division was distinctly visible last weekend at x120 with my 4" refractor.

Less clear last night. Sort of coming and going. So definitely seeing makes a difference.

[John]

Seeing is the key factor with fine details such as the Cassini Division. Spending time at the eyepiece helps too. Even if the seeing is mediocre, there will usually be moments when it improves for a second or two and your eye needs to be on hand to capture those moments

"The more you look, the more you will see" really does work

[swamp thing]

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We had Cassini all the way round, the shadow of the rings, colour to the surface markings ,the Encke and the inner C ring ( Crepe) at x240 last night.

This was with a 5mm Bst in an f6 10" Lightbridge.

Nick.

Nick that was some observing. The Encke gap through a 10", very impressed. Your seeing must have been sublime.

[Superdavo]

On a good day, I've got it at 200x zoom in my explorer 150p, but it's tricky, and needs good seeing

[John]

Thats an incredible performance, especially with Saturn so low down thus year

I get great detail on Saturn and it's rings, Cassini Division, Crepe Ring etc at up to 316x with my 12" Orion Optics dob but I've not felt I've got anywhere near seeing either the Encke Gap or the Encke minima.

I thought these details required fabulous seeing conditions and superb optics to even detect. Maybe not though.

I must look harder

[vegaandarctures]

I got it in a 10mm In a 90mm skywatcher! It does depend on seeing though

[Moonshane]

I could just detect the cassini division at 71x last night but much better at 167x.

[Cath]

Don't forget that Saturn is really quite low on the horizon for us now, so we're having to look through a lot of atmosphere, which isn't helping at all.

[John]

Don't forget that Saturn is really quite low on the horizon for us now, so we're having to look through a lot of atmosphere, which isn't helping at all.

Quite. The views of Saturn were superb last night but would have been mind blowing if the planet had been high in the sky.

[DanH]

Using my 5" refractor and an 6.7mm EP, (140x mag) I manage to see the division most of the time if seeing is good.

[michael.h.f.wilkinson]

I could see the Cassini division easily at 203x in my 8" scope, and even better at 239x. Seeing was pretty good I would say. Full report plus stuff on galaxies here.

[M4lcs67]

I was outside looking at Saturn tonight and while I had a reasonably good view, I couldn't get close to seeing the Cassini Division. I tried different variations of eyepiece including my Hyperion 10mm with both fine tuning rings, but the moment I cranked up the power the quality of the image went. Just for the hell of it I even tried attaching my 2x Barlow to the 10mm eyepiece, but that was completely bonkers. At least i'll know for future reference that it doesn't work

[John]

I was looking at Saturn with my Vixen 4" ED refractor earlier. I could see the Cassini Division clearly at 110x. The seeing conditions were good and the planet looked lovely at much higher magnification as well

[rowan46]

It does seem to be more dependant on other factors rather than just pure magnification. Last year I had a larger scope but not great eyepieces but couldn't see cassini at 127x this year I have a smaller scope better eyepieces but get glimpses at between 70 and 100x. I had resigned myself to never seeing cassini but there have been occasional bouts of good seeing even though saturn is so low last year I never seemed to get that. saturns rings are also better positioned this year. As has been said a long look at the eyepiece gives you a better chance of catching that fleeting moment. An eye test wouldn't hurt either a couple of years ago I was found to have a mild astigmatism in my left eye which I did not know I had. just bad enough to make that last bit of focus soft. It's something that is rarely mentioned but the last bit in any optical train is the eyeball