Deep-sky objects

Re: Nebulea viewing issues

Never — Wed, 08 Aug 2007 15:38:27 GMT

Also remember to try brighter globular clusters and planetaries - these tend to show color as well when the conditions are right.

/Jake

Re: Nebulea viewing issues

Amature — Wed, 08 Aug 2007 01:09:06 GMT

thanks, this is not to say im still not impressed by what i see with it:)

Re: Nebulea viewing issues

tkerr — Tue, 07 Aug 2007 23:36:20 GMT

Amature wrote:
Hey i was just wondering if i can see any sort of colour through a 8" Dobs. Reflector??

You can see a little color in Jupiter, Saturn and Mars. You might, if in very dark skies, be able to see a hint of dull green in the Orion nebula. You can see some color in some of the stars also if the conditions are right. Other than that the universe is virtually black and white with different shades of gray through a telescope.

Have A Nice ________

Re: Nebulea viewing issues

Amature — Tue, 07 Aug 2007 16:26:18 GMT

Hey i was just wondering if i can see any sort of colour through a 8" Dobs. Reflector??

Re: Nebulea viewing issues

Never — Sun, 22 Jul 2007 22:42:46 GMT

Now as promised I tried M57 with my 3" refractor less than an hour ago while looking for the comet something near M3. M57 was nearly stellar, but fairly easily visible - had to confirm it with the O-III.

This at 20x (2° 30' field). The limiting magnitude was somewhere around 4.5 or so with 35. And being a difficult naked eye object. The sky was bright enough to read Uranometria without any extra light and I could not see any deep sky objects without optical aid. The sun was 8° 55' below the horizon.

Object: Messier 57
Obs. place: Vantaa, Finland
Date: 22./23.7.2007
Bortle class: Class 5 (Suburban sky)
NE Lim.mag: 4.5^m
Background sky: 5
Seeing: 3
Transparency: 5
Sky conditions: Twilight, sun -8° below the horizon.
Weather: +11°C, humidity 87%, weak SW wind 1.8 m/s

/Jake

Re: Nebulea viewing issues

DaveMitsky — Thu, 12 Jul 2007 09:09:59 GMT

From an article that mentions NGC 6891, one of the planetaries on the list of colorful nebulae:

"NGC 6891 lies at an estimated distance of 7,200 light years, and can be found two and a half degrees south of the 5th-magnitude star Rho Aquilae. The nebula is pretty small, but has a high surface brightness. This means that at magnitude 10.7 it can be seen in telescopes as small as 4.5-inch aperture. However, high magnifications are required to distinguish the tiny 12 arcseconds disk from nearby stars."

http://www.nightskyinfo.com/archive/ngc6891_6905/

Dave Mitsky

Re: Nebulea viewing issues

Dan415 — Wed, 11 Jul 2007 18:11:43 GMT

Wow, that's an amazing difference!!!! I gotta buy one now :D, (well after I get my new telescope) thanks a ton for showing me this excellent example.

Re: Nebulea viewing issues

Never — Wed, 11 Jul 2007 17:49:50 GMT

Dan415 wrote:
So the filter is just to make it more destinct, sharper, and stand out more? If thats the case then I should get one once I get my 10"

I suppose it can be something like this:
http://www.kolumbus.fi/jaakko.saloranta/Deepsky/UHC/UHC.html

/Jake

Re: Nebulea viewing issues

Dan415 — Wed, 11 Jul 2007 17:33:54 GMT

So the filter is just to make it more destinct, sharper, and stand out more? If thats the case then I should get one once I get my 10"

Re: Nebulea viewing issues

Never — Wed, 11 Jul 2007 17:20:31 GMT

Dan415 wrote:
Is 10" view considerably differnt that in a 4" view in mag 5 night sky?

I'd say it is. The darker the skies, the bigger the difference (almost). The difference between 4" and 8" is huge.

Dan415 wrote:
Btw, if u really want to judge my location, use this link

Or you could just go outside and try the limiting magnitude with naked eye yourself

Dan415 wrote:
I'm wonderign the same thing, did u useany filters to see those colors?

No, you're not supposed to use filters to see color. That's what it is about. Many nebulae show color with filter (ie Skyglow) but it not the "real" kind.

Certain nebulae do show color just by using low magnification and dark skies.

/Jake

Re: Nebulea viewing issues

Dan415 — Wed, 11 Jul 2007 06:31:57 GMT

I'm wonderign the same thing, did u useany filters to see those colors?

Re: Nebulea viewing issues

Amature — Tue, 10 Jul 2007 21:35:24 GMT

hey i just wanted to ask, did you use any filters to see those colours that you mentioned you saw with your 8''??

Re: Nebulea viewing issues

Dan415 — Tue, 10 Jul 2007 19:18:32 GMT

Thanks a LOT dave, starwolf, and Never, I'll try a few of those nebulea tonight with the 4" telescope. With that 10" scope, think wat do u think the darkest DSO would be in about mag 5 to 5.5 skies? Is 10" view considerably differnt that in a 4" view in mag 5 night sky?

Btw, if u really want to judge my location, use this link http://bbs.keyhole.com/ubb/showthreaded.php/Cat/0/Number/269838/an/0/page/0#269838 and go to "Galloway NJ" my house is right near that location, just at the point were orange and red mix ( about a mile SW )

If I get the new scope, I'll be going to batsto state park, where its suppose to be notbly better... but its about 40min from my house D: and stargazing gatherings aren't held there often. That's why I want to know if a 10" telescope is somewhat ok for my backyard ( 3 acres all open, no lgiht from houses intefere)

Re: Nebulea viewing issues

Never — Tue, 10 Jul 2007 17:55:54 GMT

Starwolf wrote:
Also, Dave, some of the objects you listed may be beyond the limit of a 114mm scope.

Or not. All of those planetaries should be easy targets to a 4" telescope. If not, O-III or UHC filter will surely help.

/

Re: Nebulea viewing issues

DaveMitsky — Tue, 10 Jul 2007 17:16:08 GMT

Thanks, Starwolf.

The starrynights nebula list was not meant as a direct reply to the OP, although most of the objects mentioned should at least be "detectable" with a 114mm aperture from an excellent dark site. Some years ago the noted deep-sky observer Jay Reynolds Freeman observed the entire Herschel 400 list with a 55mm Vixen fluorite refractor.

A few observers have reported seeing color in some of the planetaries on the list with scopes as small as 4" apochromats.

http://www.visualdeepsky.org/netastrocatalog/msg02601.html

But for the most part larger apertures are required for any chance of color perception.

Dave Mitsky