Improving Nebulae with better eyepieces....

[badgerchap]

Hi,

Have just started looking at nebulae through my 10" dob, but having a little trouble, which I expect is caused by lame eyepieces. The scope is about f/6 and I've been trying a 25mm eyepiece, but it was one supplied with a skywatcher 130PM. Is this why M42 just looks like a milky blob??! I'm thinking of getting a 32mm plossl, maybe a televue if I can squeeze the budget but I need to know if this will really help or will be a waste of money! Thanks in advance for any help!

[Taff]

Hi' i use a 40mm EP with my 8'' reflector when looking at M42.The EP have'nt got strenth but it gives a nice field of view of the neb.In the past i have used 32mm to look at the neb which had no probs.Mark

[robneath]

just got in from looking at m42 - my 6" newt using a 20mm plossl gave me an outstanding view, then I tried the 9mm and that was a definite WOW moment- managed to resolve the E star in the trapezium so I'm well chuffed. The seeing was very good and so was the transparency - milky way was evident to naked eye as nice smudge. high cloud stopped play

[Doc]

Alot of planetary nebulas can take high power very easy. Some of these nebulas are very small indeed may be only be 0.5' accross so need high magnification to bring them alive. So I would recommend at least a 10mm maybe even higher to see the elusive ones.

Also a O111 or a UHC filter will help. I have a Baader O111 filter and this really works in isolating the nebula from the background stars.

All the above works if looking at small planetaries, if you are after the Veil Nebula then also look at a wider eyepiece that gives the largest FOV so in conjunction with a O111 you can fit a bigger chunk into your FOV.

[acey]

I agree, get a nebula filter. I use the Lumicon UHC which lets through both OIII and H-beta lines, otherwise get an OIII filter.

The other important thing is the darkness of the sky.

A filter works by cutting some light and improving contrast. Light pollution reduces sky contrast and makes extended objects harder to see. So a filter can be a big help on nebulae at light polluted sites.

From a dark site I prefer the view of M42 without a filter, but I still find it improves very faint nebulae.

Some eyepieces give better contrast than others - TeleVue Plossls are very good and the 32mm is great for wide-field views. But something like the 20mm will show more detail.

[John]

Hi,

Have just started looking at nebulae through my 10" dob, but having a little trouble, which I expect is caused by lame eyepieces. The scope is about f/6 and I've been trying a 25mm eyepiece, but it was one supplied with a skywatcher 130PM. Is this why M42 just looks like a milky blob??! I'm thinking of getting a 32mm plossl, maybe a televue if I can squeeze the budget but I need to know if this will really help or will be a waste of money! Thanks in advance for any help!

I keep posting this advice so sorry if I'm beggining to sound like a stuck record but seeing astro objects through a scope takes time and practice. There are relatively few objects where all the detail is immediately aparrent. it's all too easy to blame the equipment when the real solution is to take time at the eyepiece, develop observing techniques such as averted vision, allow your eye to become "trained" in picking out faint details, allow your scope to properly cool down, find the darkest spot to observe from etc, etc.

I have a set of expensive eyepieces but, if I'm honest, I can see 90% as much detail through bog standard ones.

When you read reports of observers seeing faint and vague details of objects that are not jumping out at you when you look at the same object it's just as likely that it's their experience that's making the difference rather than just the equipment they are using IMHO.

"the more you look, the more you see"

John

[brianb]

it's just as likely that it's their experience that's making the difference rather than just the equipment they are using IMHO.

Very much more, I reckon - the difference between a £20 Plossl eyepiece and a £500 Ethos is at most 20%, with one year's "training" your vision will improve so much that it's like doubling the aperture of the scope.

Of course it's easy for advertisers to try to fleece us of our money by insisting that the latest wonder product will solve all our difficulties, but it just ain't so.

If you have a f/6 Dob, and no eyepiece longer than 25mm, of course a longer one will improve the view of "faint fuzzies" ... especially if your scope has a 2" focuser - but there's simply no point in spending as much as the scope is worth on a top-of-the-range eyepiece - especially with a Dob, as the weight of these "hand grenades" can cause balance difficulties. Try the 2" fitting Antares W70 34mm for a big improvement at a reasonable price. 40mm is too long for a f/6 reflector unless you have exceptionally dark skies and young eyes.

[badgerchap]

Hi Guys,

thanks for all the help. I think I've worked out what to do. Am gonna get myself a 9mm and 25mm celestron omni plossls and combine them with a lumicon UHC. Should cost me around £150 altogether which is about my current budget. I think this should sort me out. Any thoughts?

Cheers

[acey]

Others have correctly noted the importance of eye training.

With the Lumicon UHC you'll certainly see a difference in emission nebulae - though don't expect it to be enormous. I doubt that the eyepieces will show you much difference, until you've used them a lot.

[albedo0.39]

From a dark site I prefer the view of M42 without a filter, but I still find it improves very faint nebulae.

Can only agree with this 100% - when I went to Kelling recently, we got to about 2:00am and looked up and remarked that Orion looked like it was on fire - it was so bright and the skies were very dark.

And then I looked into the EP at M42

Gosh....