How many inch" dob do I need to see dust/gas in Orion/M42 Nebula?

[mbaddah]

Hi there

Just wondering what dob size would I need if i wanted to see dust/gas in Orion Nebula? I understand you won't be seen it anything like astrophotos, but I've heard can still be sighted? I may be wrong... your feedback is much appreciated thankyou.

[iceman]

I can see dust/gas in the ED80! It's very bright, you can even see it binoculars.

The bigger the scope, the more nebulosity you see. With very large apertures, some even start to see some greeny/pinky tinge of colour.

[h0ughy]

is there anyway you can get to a close astro club viewing night to wet you palette?

[erick]

In dark skies, the Nebula in Orion (M42 in particular) is naked eye visible. As Mike says, add a pair of binoculars (from, say 7x magnification to higher) and it is a marvellous sight. In my 8" reflector, the nebulosity in the "Sword" is lovely and, with dark skies and eyes adjusted, I can start to make out the dust lanes in the Flame Nebula near Orion's belt.

More experienced observers say that you can start to pick up colour in the nebula with a 12" reflector.

I hope this helps. :)

[mrsnipey]

I concur. I have a 12" dob and it looks slightly bluish in colour to me.
It's absolutely fantastic to look at.:D

[Satchmo]

The nebulosity shows up pretty well in my 42mm binoculars.

Mark

[mbaddah]

Firstly thankyou for all your replies.

I found a webpage (located here http://www.my-spot.com/whatkind.htm) and if you scroll down the page, he has a section where compares visual to photographing orion nebula.http://www.my-spot.com/images/m42-vs-eye.jpg

I know i can't see that with my 6" dob, any suggestions? Thanks guys.

[Satchmo]

You might need to get out to a darker sky then . Where are you observing from ?

Mark

[mbaddah]

Currently viewing from my backyard (I know not the best seeing). i have gone to few other parks around the area away from most lights. Perhaps i'll try Gosford/Blue Mountains this weekend see how I go. Reckon you can see much with 6"?

[erick]

Absolutely yes! Once you know what to look for, where to look and get experienced with using techniques such as averted vision.

How long have you been using the 6" and what have you been looking at?

There's several galaxies, nebulae, globular clusters, open clusters, double stars, coloured stars - plus Moon and planets - all within reach of a collimated 6" reflector!

[janoskiss]

Use a low power eyepiece (FL >= 20mm) from a reasonably dark site - well away from light pollution source, min. 50km from major city, 20km from large town (parks "around the area" won't do if you live in a city; light pollution travels a long way) and you will see heaps of structure in M42 with the 6" Dob. Looks a lot better than the simulated picture you've linked above.

[mbaddah]

Have been using it for few months now.. I am a beginner though and learning everything on my own :(

Have been looking at few clusters, moon, Jupiter (never seen the GRS unfortunately) and Mars. But want to extend my search to nebulas.. and thought I'd start with the Orion.

[mbaddah]

Thanks for the tip, i'd be amazed if i seen something better than that picture! This weekend then hopefully can go somewhere with good seeing,blue mountains ?

[erick]

Do you have suitable charts, or a planetarium program? Try this sky map, a free download:-

http://skymaps.com/downloads.html

You need the Southern hemisphere version and if you can print it on A3 paper, that helps a bit more. Lots of suggested targets are given.

This weekend, try to locate the galaxy NGC 253, the Orion nebula M42, the Tarantula nebula NGC 2070, the globular cluster 47 Tuc (NGC 104), the open cluster NGC 4755 (later in the evening when it rises higher above the southern horizon), the galaxy M31.- they are all on the sky map you downloaded above.

Get away from Sydney as much as possible - its sky glow extends more than 100km! Get away from direct lights to allow your eyes adjust to the dark for 40 minutes. Use a redlight torch to look for things and examine the maps. Relax, and don't try to push the magnification beyond around a 20mm eyepiece, until you have an object that is worth magnifing.

Let us know how it goes! :)

[mbaddah]

Thanks for the tips will do best I can to implement in coming days... will report back hopefully with good news :)

[ballaratdragons]

I used to be able to see it clearly in my old 114mm reflector! Even better than that link shows visual!!!

In my 12" I see the the whole neb in slight Green and pink shades. Our Clubs 8" shows it just as bright but without colour. Your 6" should almost be as good from a dark site.

It is best viewed with 20mm - 32mm EP's.

Here is an eyepeice view of how I see it visually from my dark sky in the 12"

[PCH]

Wow Ken, - that is spectacular:eyepop:

Now I know what's possible, it looks like I too should move towards darer skies.

Cheers :thumbsup:

[ballaratdragons]

Close one eye and look at the attachment. That's exactly as I see it here :)

Dark Skies Rule!!!! :thumbsup:

[mbaddah]

BEAUTIFUL! That's what i want to see! Looks like i'll need a 12" to get colours you mention.. Thanks for that.

[ballaratdragons]

Before jumping in and getting the 12", consider these:

Transport - the 12" doesn't fit into all cars.
Weight - It can be a heavy OTA for some people.

ummmm . . . that's about all I can think of :lol:

Oh, and dark sky helps.

Otherwise, it is a great scope :thumbsup:

[§AB]

I've got a 10" GSO Dob and absolutely love it! She'll perform nicely to well over 400x in good seeing, she shows me alot and frankly, 10 inches is a perfect compromise between light gathering power and portability. The OTA (16kg) is easy to carry in hand, I can fit it into a station wagon with ease and 10" aperture will blow you away at dark sky location. Oh yes, the ORION NEBULA is sensational from my light polluted locale. You can see intricate detail in the core in good seeing and it is very bright :D

If price, weight, portability are an issue, get a 10" GSO. You can't go wrong!

[rogerco]

Why not check out the WSAAG website and come up to the next viewing night at Linden Observatory. You will get goo instruction on how to make the most of what you have, there is at lease a few others with similar scopes. an get to try other scopes as well.

Roger

[CoombellKid]

From a dark sky, like my backyard. You can even see it naked eye, with averted vision :D

regards,CS

[jjjnettie]

I can see shades of green in M42 through my 10" Dob.
But...
There is more to observing an object than just looking through the eyepiece. It's a skill that you build up over time.
You need to take your time because "The more you look the more you see." Spend at least 10 minutes examining an object so your mind can grasp the detail. Use averted vision to catch more intricate detail, look at it through the corner of your eye, your peripheral vision. Even tapping the side of the eyepiece to get a little wobble up will bring out detail you couldn't see before. You'll need to build up the skills before heading off to find the faint fuzzys.

[francis]

HI,

I just assembled my new 8 inch Reflector Dobsonian mounted. I have 25mm & 10mm Plossel lens's (1.25) and a 2.5x GSO 3 element Barlow. I have collimated using the laser device which was really easy and will double check with a Cheshire. I also have a 2" inch adapter.

I am wanting to know if this is sufficient / suitable gear to view mars with on a good night? (Victorian)

Also, should I be buying 2" lens's. I am unsure if wider means less magnification?

many many thanks your assistance this enquiry,


Peter M.

[CoombellKid]

Hi Peter, and welcome to IIS.

In a word Yup! it sure is. I'd be using the 10mm and if the seeing is really
good try throwing the Barlow in with the 10mm. Using the barlow with
your 10mm will give you the eqivilent 4mm. Is your 25mm also 1.25"?

Have fun

regards,CS

[erick]

Bravo Peter! You are in business!!

Well, you can see Mars without your telescope - it really sticks out at the moment!! With your telescope, you need to try when it is at its highest, if you can wait up until about 2am at the moment. You'll definitely see the planet as a red/orange disc, but the seeing conditions will determine whether you can see any features on the surface. You just have to try.

2" barrel diameter versus 1.25" barrel diameter eyepieces - Not really an issue of magnification. Various brands make a large range of focal lengths. It is true that, in general, lower magnification eyepieces are generally in the 2" area and higher magnification are often in the 1.25" area. Of more importance, to my understanding, is the apparent field of view of the eyepiece. Different eyepiece designs give a different apparent field of view and sometimes this is limited, as I understand it, to the barrel diameter. 2" eyepieces can also be heavier so telescope balance (for a dob base) can be important - but there are heavy 1.25" eyepieces as well.

As has been said before - best you get familiar with your own equipment and its capablities, then go to some observing evenings and see other equipment in operation. If you ask nicely, you may be able to borrow an eyepiece or two and try it in your own scope.

Tell us what you see!

Eric :)

[§AB]

M42 through my 10" on a dark night with a filter is totally green and very bright.

As for Mars - pfffft!

[Brian W]

Thanks, My wife and I are currently using a 4.5" reflector but will be upgrading in April. we have been going back and forth between 8 or 10 and your photo has settled the issue. It will be a 10" dob. (the twelve is just too hard ie expensive, to get to the Philippines.)

[MrB]

M42 thru my 6" f5 dob with 25mm Plossl is a great sight.
I'm in the city but light polution isn't that bad, can see 5.5mag stars naked eye with last nights moon, and occasionally a 6th mag will flash into view.
This may cause some arguments (flame suit-on) but I definitely see a very slight green tinge in the 6", tho no pink at all. It's not something that sticks out tho. The tinge is only noticable when comparing with the white-ish stars in the same field.

[Brian W]

No flame from. We have a 4.5 reflector and very dark skies. My wife claims a light green tint and I swear to a light purple tint in M42. We agree that it is subtle and definitely needs a dark clear night to see the feint colour.
Brian W

[Dujon]

Mbaddah,

You are doing well. I used a wee two inch (50mm) refractor when I viewed the Orion nebula for the first time. I was fortunate to have good 'seeing' and my young son around at the time. Whilst it was not as detailed as some of the images posted here and elsewhere it was the most wonderful sight I'd managed to see at that point in time and my son - in his early teens at a guess - was quite impressed.

Through the refractor it appeared to be green - no hints of red.

[Kokatha man]

Well, just for the record, at low/medium mag (approx 50-100x) I see this hairy, maniacal face somewhat akin to Gandalf...............but my wife tells me that it's more like a Walt Disney Merlin; but no matter how much we drink beforehand we can't see colours.....