trapezium in orion nebula

[asimov]

How many stars in the trapezium can you see thru your scope with direct vision?:poke: :D

[davidpretorius]

none at the moment, clouds and rain!

[Robby]

6.

[ausastronomer]

In your 12.5" scope you should get 6, 90% of the time depending on conditions and elevation, sometimes you may only get 5. Elevation and transparancy are important factors in seeing all 6 using scopes in the 6" to 10" range. Usually in 4" and 5" scopes you will only get 5 and may if your lucky occasionally get the 6th (F star).

CS-John B

[Starkler]

I get six in my 10 incher viewing from my backyard.
Four are obvious and the other two are quite faint and visible only under fairly high power.

I get four easily in my ED80.

[Exfso]

Depending on seeing and damn weather I can see 6 in the 5" tak.

[Mick]

On a good night 6 with a 12" Dob.

[Rodstar]

I've never seen more than 4 in my 10" SCT. More patience and higher quality EPs may be in order!

[ausastronomer]

Rod,

They are always tougher in a SCT. Due to the number of optical surfaces inherent in the design ie Corrector Plate, Primary, Secondary, Star Diagonal and also the size of the central obstruction you will not have the same light transmission as a Newtonian or a refractor. Not a great difference but definately down a couple of percent which can matter when your talking borderline objects.

All is not lost :) You just need to get things in your favour.

High Altitude (hence less air to look through)
Good transparency
The correct magnification is important. In your 10" scope somewhere between 120X and 180X should be the zone. Your 16mm Nagler T2 should be fine. I will help you in seeing them next time Orion is well placed and we are together, if the 16mm Nag isn't fine I will lend you my 20mm Pentax XW.

CS-John B

[Astroman]

I have seen 6 in my 8" F7, using a nagler for an EP, only 5 with standard plossls. This was at a semi dark sky too.

[astro_south]

Always see 6 in my 12.5" f6 dob. When the seeing has been very ordinary I have had to put a bit of effort in to tease the "f" component out, but I never gone without seeing all 6. My 4" short tube achromat has shown me the "e" component on a few nights of good seeing, but never the "f".

[Rodstar]

Thanks for the encouragement, John. I think the Nagler you are referring to is Louie's!
Hopefully next summer / autumn I will have more luck!

[Starkler]

I never saw them myself until I knew where to look, then they stood out like the proverbials

[ausastronomer]

Rod,

I know the 1 we were using the other day at Kulnurra was Louie's but I was sure you had a 16mm T2 at SPSP or was that a 12mm T2 ?

Cs-John B

[asimov]

Thanks for the replies gents. Just wondering what others saw. I see 6 easy with the 12.5" The achro usually shows me 5 but on very favourable nights 6.

Thanks again.

[xstream]

John,
There was a 16mm T2 that Robby bought with him and 12mm T4 which belongs to my wife.

[Striker]

4 for me....I could only see 6 out at a dark site.

[iceman]

I've seen 6 a couple of times, 5 more times, and 4 all the time. Seeing has to be fairly steady for me to get the "f" component. I'm sure the trap will be the subject of one of the summer MOC's :)

[gbeal]

6 on a good night, with anything bigger than my 80mm. The 80 shows 5 and I have yet to see 6 with it. I reckon though that the Trap is seeing dependant, much like Antares.

[ving]

I have only seen 5 thus far, but I havent really looked for more... I'll have a go when its out at a reasonable time :)

[RAJAH235]

I've seen 6. Normally on a reasonable night, with the 12.4 SP @ 92 X, they stand out really well. The 9.7 SP @ 117 X shows them a little better, but as you know, it all depends on the conditions. :D L.

[asimov]

Oh! I didn't even know theres more than 6 in the trapezium. Thanks L. I'm gonna have a go at seeing more than 6.

[RAJAH235]

@ 15.8 and 16.7? Need excellent seeing. Good luck. :thumbsup: :D L.

[ausastronomer]

The 7th "G" star was discovered by A.G Clarke in the 36" refractor at Lick Observatory so your gonna need more than good luck and good seeing :)

Cs-John B

[asimov]

:D Ok...So I'm gonna need LOTS of luck?! :rofl: No harm in trying hey? :)

[asimov]

Saw 4 using the 15X70 binos a couple of mornings ago.

[RapidEye]

I bagged 6 a couple of mornings ago with my 10" Newt with "good" seeing, but not "great".
On a couple of exceptional nights, I've gotten 6 with my 4.5" Newt. Its one of my informal seeing tests with my 4.5":
4 Stars - bad to average seeing
5 Stars - good to great seeing
6 Stars - great to awesome seeing

<shrug> it works for me =-)

[dhumpie]

Yup I think there is a concensus here. I see 6 routinely in my C6 and 5 in my Orion 80ST. Have not had a chance to try that out with my 102ST yet though.

Darren

[davidpretorius]

Ok, tried the trap tonight and still only 4 even at 400x and 480x.

Focussing in an out, i really believe my collimation is not spot on or my optics aren't up to it. One star looks like a smudges double.

Can't wait til camp to get some help on collimation for beginners!

[iceman]

It's really the seeing that will effect it Dave (as well as collimation). You'll need 200x or less to see E and F if the seeing is good.

[davidpretorius]

seeing was pretty good, mars at 400x was not bad and yes collimation!

[Starkler]

Saw 5 last night in the ED80 from my moonlit backyard .
Makes it much easier when you know where to expect to see them.

[xrekcor]

I'm almost always been able to tease out E & F even in reasonable conditions using a
10mm XW @ 120x. In pristine conditions using 350x (3.5mm XW) they fade away. So
120x seems to work best for me. Also I guess knowing where to look helps, thanks to
Astro_South.

With components H & G sitting @ 16+ I'll need a scope upgrade or a bionic eyeball.

Has anyone using say a 16" dob been able to tease out H & G? what about you astron?

regards,CS

[atalas]

I have seen Six in aperture as small as 4" Tak on a good night ,on the matter of SCT John is right in saying that the conditions need to be good and Geoff saying (You have to know where to look ) now you might think your SCT is collimated well but did you check It at 400X ! thats where you'll get good collimation for these scopes. When I had a C8 I had no trouble with five and many times with six when the seeing was good.
I even managed to split 0.8 gamma centuri on a good night with a C8 at 300X and hey I'll tell you now both my Tak's couldn't do It !

[atalas]

Davo that mag is to high ! you'll have better luck between 150x too 200x I think
at least that's what It has been for me mate . Otherwise you loose too much light !

[ausastronomer]

David,

Louie is right, that mag is way to high. In an 8" dob somewhere between 100X to 160X will bring them out. The important thing is good transparency, also let them get high in altitude and fair seeing also helps.

CS-John B

[xrekcor]

Davo,

If you want to see doubles at high mag try Alpha Centuri @ 400x it'll take it :thumbsup:

but it will appear like a Mack truck is about to enter your scope :)

regards,CS

[RapidEye]

With my 4.5" F/8 - 5 on a good night and 6 on a great night!
With my 10" F/5 - 5 on most but horrible nights and 6 on a normal night!

[Nightshift]

I didnt know there was more than 4 until I got my 12" dob the other night, now I can see 6 easily, it does take a bit of power though, it wasnt obvious until I used a 15mm EP or better.