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Nico13
08-03-2011, 08:44 PM
Hi guys and girls,

Had previously posted this question in the wrong place in Deep Space imgs forum and was wondering why I wasn't getting any responses to it after fourty views and no answers so maybe in the right forum might help.

Just a quick question on what I can expect to see with my Old Meade 8" SCT when looking at Galaxy's. It's mounted on a Supr Polaris EQ mount with a Meade goto drive all sitting on a moveable pier

I still don't have my tracking/guiding sorted well enough for long time exposures but with the Galaxy fields in Leo and surrounds coming into play now it's a perfect oportunity for me to try my luck at finding and viewing them.

So can I expect to see much and what eye pieces should I be using etc, I also have a 2X doubler I purchased recently and I would dearly love to look at M104 the Sombrero Galaxy as it's also up now as you will know.

Very greatful for any help, working night for the next two weeks so got a bit of time to think about setup.

Nico.

Lester
08-03-2011, 09:17 PM
Hi Ken, an 8" SCT would be fine for looking at galaxies, as I use to do just that. I would suggest the best asset would be if you can view from dark country skies away from any light pollution. A 32mm or a 25mm eyepiece would be a good starting point. All the best.

toc
08-03-2011, 10:04 PM
Yes I think dark skies are a must for galaxies - In my light polluted skies I dont see too many galaxies with my C8.

Nico13
08-03-2011, 10:30 PM
Thanks guys,
It's just nice to know that before I start my hunting that I'm not going to be pushing the proverbial muck up hill with a stick.

I'm about a half hr west of Geelong and while there is light polution about it's not too bad on a night of good seeing.
Got home from work last night, well more like 1:30 this morning and stood out the back with the bino's just looking around and the milky way overhead was just blowing me away.
Unfortunately too dam late to start dragging the telescope out at that time.

Back on dayshift in a couple of weeks though should be good I hope.

Nico.

GrampianStars
09-03-2011, 07:38 AM
You'll see heaps with the 8" from where you are Ken :thumbsup:
Get yourself a filter like:-
https://www.bintelshop.com.au/Product.aspx?ID=7594
Happy Galaxy Hunting ;)

Lismore Bloke
09-03-2011, 09:50 AM
Hi Ken,

I love finding galaxies and have seen quite a few from my location, which is outer suburban with moderate light pollution. Admittedly, using the 12" helps matters but an 8" should also be fine.

I find that using the correct eyepiece is very helpful. I started out using things like the Nagler 22 and 17. I now use the 9 and 12mm. The increased magnification brings better contrast. Many galaxy cores have a high surface brightness and using higher magnification helps pick out the smaller galaxies from the starry background.

I have the O-III filter and UHC also but don't use them on galaxies as they don't help, rather they dim starlight. They work fine on nebulae. The O-III is great on planetaries.

Cheers, Paul.

AstroGuy
09-03-2011, 10:26 AM
GrampianStars, I don't know if you meant to use this type of filter for visual use but....

It's not adviseable to use narrowband for visual use. Primarily because the narrow band of light waves they do allow to the eyepiece are to dim for the human eye. They're great for sensitive (very low lux) CCD long exposure use though.

But then again, if you eat lot's of carrots you may be able to use this type of filter for visual use.....:) All astronomers should definitely boost their vitamin A intake to elevate their viewing experience! :cool:

Lismore Bloke
09-03-2011, 10:31 AM
A common recommendation is to use an eyepiece with an exit pupil of around 2mm for galaxies.

The following site has some info:

http://www.astronomics.com/main/category.asp/catalog_name/Astronomics/category_name/J34KLLT872239NV4HBW7FSRMB1

Cheers, Paul.

astroron
09-03-2011, 10:58 AM
Rob, I hope you are not suggesting that an O111 filter is any good for galaxy hunting:question:
Cheers

GrampianStars
09-03-2011, 11:15 AM
For me it is as I suffer from protanopia (missing long-wavelength pigments in my eyes)
i.e. What you colour-normals would describe as red and green does not look red or green and is dark compared to other colours that are actually equally bright.
mainly Nebs though, Veil (NGC6960) (faint middle section) and the Helix (NGC7293) and the Dumbell (M27).

AstroGuy
09-03-2011, 11:22 AM
So, anybody have any recommendations as to what filters (if any) would be good for Galaxies? I've not had much success in viewing a fully blown galaxy yet on my Celestron 4se. I have however seen them as small visual imprints in my eyepiece, but hopefully when I get my Saxon 8" Mak up and running....:whistle:

astroron
09-03-2011, 11:30 AM
As galaxies emit the full range of light from the Electro magnetic Spectrum, No filter would be any good for galaxies.

renormalised
09-03-2011, 11:45 AM
The more aperture you have the more you will see, but you're not going to see some ultra bright, grand spiral structure in any of the galaxies you look at, like you see in books. Especially with an 8" scope...to see any colour at all in most galaxies, you'll need a big scope, emphasis on the big. Even then, it depends on your own eyes and perception of what you're seeing.

An 8" will show some spiral structure in the brighter galaxies like M31, M33, M100, M51 etc, but don't expect to see much with many of the galaxies except faint smudges.

robz
09-03-2011, 12:21 PM
I see that you have a GSTAR -EX video camera.
How do galaxies appear when using one of these special ''super astro video cams''?'

renormalised
09-03-2011, 12:31 PM
Very good...you can see a lot more than when you're just looking through an eyepiece. You can also make out colour much easier as well. Especially in brighter objects like nebulae and such. Although, my camera is mono, but a few people I know have the colour version of the camera and I've observed with them. I'll be getting a colour version sometime soon. I'd like a Mallincam, but they're a little expensive.

I would recommend buying one...they make it much easier to see faint detail in dim objects as well as for very good views of the brighter ones. Also, if your eyes aren't as good as they used to be, they make visual observing a much easier and more pleasant task:):)

AstroGuy
09-03-2011, 01:31 PM
Hi Ron,

So, worst case scenario would you consider a LPR filter if living around the city limits? or would that spoil the view? Probably better off arranging to go a nice darksite huh? oh.....and eat lot's of carrots beforehand heh heh heh.:lol:

astroron
09-03-2011, 02:17 PM
Hi Eugenio,LPR filters may cut down on the light Pollution a bit, But in MHOP, your only remedy is "NICE DARK SKY":D or imaging:rolleyes: and the carrots will just help to keep your stomach full;):lol:
Cheers

Nico13
09-03-2011, 05:09 PM
Thanks guys this is all great info and while I may be in a reasonable area for low light polution if I want a good look at them thar Galaxy's I'd better do something about size or go go visit my mate Lance with his 12" f4 newt for a better night out looking at Galaxy's.

And Paul thanks for the link on eye pieces it looks like I need to do a bit more reading to get a better understanding of what setup is best for what.

This is all interesting and keeps the brain busy just thinking about it. :question:

Nico

mental4astro
10-03-2011, 11:36 PM
An 8" SCT is a very capable galaxy hunting scope.

I've just got my hands on an old orange tube C8, and did a "first light" write up in the Obs. forum:

http://www.iceinspace.com.au/forum/showthread.php?t=72842

In it I describe observing M104, the Sombrero Galaxy. I had my first light with this C8 from my home in Sydney, so Geelong skies shouldn't be as nasty.

There are a mass of galaxies coming up this month you can try for, all within easy grasp of an 8" scope. Especially in the constellations Leo and Virgo, including many double and triple groupings. The current March Obs. Challenge lists several of these:

http://www.iceinspace.com.au/forum/showthread.php?t=72597

You can first try locating them with as low a power EP as you have. You can then try upping the magnification as this helps lower the background sky glow, making the faint fuzzies a little easier to see.

Mental.

White Rabbit
13-03-2011, 10:39 AM
I have an 8" newt and live in very light polluted sky's and I've never seen a galaxy. Hell, I've never seen one with my 12" let alone the 8.

astroron
13-03-2011, 11:07 AM
You should see lots of galaxies with an 8" scope
I did a visual Supernova search for about ten years with my Celestron 20cm SCT and saw Supernova stars down to 14.5 magnitude in galaxies to 13mag
Dark sky's are a big advantage but some of the brighter galaxies are visible in medium polluted sky's.:thumbsup:
cheers

mental4astro
13-03-2011, 12:08 PM
You should join us on our regular-ish get togethers at Randwick Girls' High. Last session we about a month ago, we bagged M104, M83, M65 & M 66, M95 M96 & M 106 and NGC 5128. All in scopes from 8" to 17.5", ;) .

M54
13-03-2011, 12:48 PM
An 8" is totally adequate for galaxies.

My scope is a 5" and I've seen M83, M104, ngc 5128, M31, M110, M32, and more, albeit from a dark sky site.

I wouldn't be able to find them from suburbia.