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After a couple of unsuccessful attempts, tonight I found M13 the globular cluster in hercules, it was a bit of a race between cloudy spells but with the help of 2 bottles of becks, some chilli crisps, Mr Telrad and alot of patience (the clouds groups were moving fairly fast so had to be quick) I found it. Got about 5 to 10 minutes of observing time and am very happy.

I couldn't resolve the cluster very well, LP is fairly bad here and I only currently have the stock SW 25mm and 10mm and a Seben 2X barlow. M13 was only really worthlooking at with the 25mm alone, when barlowed it smudged more and the 10mm was pretty much a waste of time. What sort of magnification will show up clusters like M13 to the best effect? Im hoping to get a 68 degree 20mm maxvision soon (pending my car being fixed and seeing what cash I have left).

The Seben barlow seems OK at the moment generally ( I actually bought this budget barlow for my daughter who has a minidob) but am aiming to probably get a Tal at some point, I hear they are about teh best for the price you can expect to get.

Still, a good evening and Im off to bed happy :)

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M13 should handle a fair bit of magnification... I prefer it at around 90x or so (13mm for me). As it gets lower in the sky it will be harder to resolve (it's getting pretty low now unfortunately). In terms of EP selection, I view most globs almost exclusively through my 13mm (good excuse for an EP upgrade me thinks! :grin:).

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As Andy says, most globulars should handle magnification well and are one of the night sky objects that generally require higher magnification but you will find that this power input will vary from night to night (atmospheric conditions) and from cluster to cluster (their own unique personality).

Within reason, I generally feel one has no need to go beyond 200x on any DSO. Light loss simply out-weighs what might be gained by power and in my own experience somewhere between 100x to 175x hits sweet spots on just about any globular cluster I've seen.

If it helps, I travel with my gear and like to keep things simple but regardless, 85% of my DSO viewing, sketching and hunting is conducted with just 3 EPs on the 10" f/5: 24mm (52x, 4.8mm exit pupil, 1.3 FOV); 14mm (90x, 2.8mm exit pupil, 0.8 FOV) and a 10mm (125x, 2mm exit pupil, 0.5 FOV).

It's not a great sketch but at a really dark site and some concentrated sitting, M 13 took on an appearance something a little like the sketch below and I feel your 8" should be able to do very much the same.

Good luck and keep us informed :smiley:

post-21324-0-74374300-1377908070_thumb.j

Edited by Qualia
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Actually, I think it's a fabulous sketch, I can only wish!

It's worth remembering that some DSO's are only genuinely appreciated through a wide FOV.

Alex

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I tend to observe M13 at x120; gives the right balance for me between magnification and brightness. Oddly enough, that means using my stock 10mm eyepiece (the weakest of my setup by a long chalk) but I've still had some great views with it and my 200P. One day in the not too distant future I'll be looking to upgrade my 10mm...

PS: fantastic sketch Qualia! Wish I had a tenth of your talent! :Envy:

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M13 is a 150-165x object for me.

I always go as high as I can on everything just to see what it looks like, you don't know unless you try. Find what works for you and what pleases your own eyes, that's my best advice I can give really. It's about enjoyment at the end of the day. If you like seeing things dim and dark and whooshing through the eyepiece at 450x then go for it :)

EDIT: I have actually done that by the way, the 450x thing. I lined up the eyepiece in advance of where M13 was going to be in 15-20 seconds (using the finderscope) and then went to the high power eyepiece. It's quite fun waiting to see how accurately you have placed your spot and then you see the first outer stars creep into the field of view and then it comes on, relentlessly pushing into view and sweeps across the field like a giant, interstellar ice flow on a rapid galactic river, driving past and then as quick as it arrived it's gone.

There are all sorts of ways to have fun :)

Edited by Stargazer_00
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That's a brill sketch in post # 4. If anyone hasn't clicked on it for a good look, worth scrolling up to check it out.

Agree that globs take power well, I find that between around 90 to 150x is good with my 10" Dob, according to sky conditions.

Under very good conditions, looks like that sketch.

Regards, Ed.

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What magnification you use depends on how you are wanting to observe the cluster. Low power is fine for getting an overall impression of the object, but if you wanna resolve the area around the core. Your gonna need to push power way up, and get inside the cluster.

High mag is going to help pick out those stars right on the limit of visibility. It blackens the background out, gives better separation.

Don't be scared to really ramp power up when observing globs. Dark skies obviously help as well. :)

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Hi,

I saw M13 last night on my first light and was well chuffed - I only have the stock lens so best magnification was 120x but still looked pretty good and as it was my first Messier object now holds a special place. Looking forward to the bigger mags!

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It is beautiful to look at isn't it Phil, I still remember the first time the fuzzy ball of light was suddenly resolved into a glowing sphere of stars. Magic! :)

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At a dark site M13 is easily visible in binoculars or a finder as a fuzzy patch. How much magnification you can reasonably use on it depends on aperture and sky darkness - just keep raising the power until nothing more is gained. The brightest stars are around mag 11 to 12 so for a detailed view you want to resolve those. An 8" will do it easily, but light pollution kills the faintest stars and also stops the eye adapting properly. So the best thing is to get the scope to a dark site, then M13 will look superb, and you can also look for details such as the famous "Propeller".

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Thanks for all that guys, I cant wait to get some better EPs but struggling with cash, car repairs and other rubbish at the moment so doesn't look too hopeful for a month or two :S

Last night was dead clear here but the wife wanted to watch a film so didn't go out, but hopefully tonight will be nice too.

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