Size of Veil Nebula

[Adz]

Hi all,

What is the minimum true field of view and eyepiece has to give to fit in the whole of the veil nebula for a worthwhile visual experience?

Also am I right in thinking it is one of the widest objects in the sky to view with a telescope? The others I can think of are Andromeda and its companion galaxies. Any more?

Thanks,

Adam

[Moonshane]

the Veil is about three degrees across but even a 1 degree view gives great views with an Oiii filter and decent skies.as you say, other large ones are M31 also about 3 degrees, M45 2 degrees and M44 about 1.5 degrees. Wikipedia gives approx dimensions of most objects.

[Adz]

Thanks for the input Shane. By my calculations you would need a 100mm f/6 frac or an 80mm f/7 frac with a eyepiece of 2" fitting with 22mm or more focal length.

[Moonshane]

you get (I think ) about 2.4 degrees with your Tal 100 and 35mm Panoptic? this would give a great view for starters?

[Adz]

I should hope so, on the Veil it would really prove itself I guess. But it's performance on every other object I have tried against my 200p hasn't been as good.

[Moonshane]

that's my view, basically. aperture rules for visual. there's no comparison in my opinion between the view in my 16" dob and the 90mm frac, even though the latter showed the whole thing.

[Adz]

Point very duly noted, aperture rules

What is the largest exit pupil that would be okay for a big dob? either 12" or 16"

I ask because it would make sense to work that out and then get an eyepiece which could provide the widest view with that.

Would a 31Nagler be too much for example?

I see many people stick with the 26Nagler. Even the 35mm Pan is uncomfortable in my 8" scope.

[Moonshane]

my 16" is f4 but I had a 12" f5 previously and the 26mm Nagler is better in both. I sold my 35mm and 22mm Panoptics to buy the 26mm and never regretted it. to be honest though I also regret selling the 24mm Panoptic I had before the 22mm.

The 26mm Nagler is my most treasured eyepiece, it's superb.

[Adz]

This is what I was thinking of doing with my two Panoptics, it seems like a good choice. I just want it to be worthwhile. They must be good, they never come up 2nd hand!

Why do you regret selling the 24mm pan?

Whats the eye relief and positioning like on the 26mm nagler? I would hope its like the 24mm panoptic as that is my most comfortable.

[Moonshane]

I think the 24mm Pan is the best widefield eyepiece available in a 1.25" fitting and I may even buy one in the future if funds allow and sell my 32mm Plossl. it's just so easy to use and lovely and sharp.

I'd say that the 26mm Nagler is in the same bracket but somehow more immersive. also extremely easy to use with no issues at all with blackouts. it's perfect (but of course very big cf the 24mm Pan).

[Adz]

I couldn't agree with you more about the 24mm. It is also really nice in my PST as a low power. The 26mm nagler sounds very nice, guess I will just play the waiting game and also sell the 35mm Pan

[umadog]

Yep, the 24 mm is awesome.

Getting a good view of the veil doesn't require fitting the whole thing into the FOV. Then the details of the object will be too small to be visible. If you can fit most of one portion of the object into the field at any one time that would be ideal (i.e. the eastern or western veil). The most pleasing views I've had of the veil have been with a 12" f/4.9 and 31 mm Nagler, or a 10" f/4.8 with a 24 mm Pan. I was underwhelmed with the view through a ~90 mm refractor that did fit the whole object. In big scopes (>16") you see more detail but loose a little of the feeling you get with a smaller Dob.

There isn't really a maximum exit pupil. Once the exit pupil gets larger than your eye's pupil you stop seeing a brighter image but won't become fainter. If you view the moon through an eyepiece with a large exit pupil then you may see the central obstruction. This won't happen on DSOs since your pupil dilates for these objects. For a while I observed quite happily with an 11 mm exit pupil from a 55 mm Plossl. Eventually I traded that in for a 30 mm 82 degree. Same true field.

[ollypenrice]

I've used two setups to see the entire Veil, an old Genesis (100mm F5) with 35 Panoptic and a TV Pronto 70mm with 26 Nagler. The Genesis could just about show it unfiltered but both scopes show it well with an O111 filter.

Another big one, likewise seen in both, is the Rosette.

Olly

[swamp thing]

Let's not forget the North American Nebula, that's a huge object too.

I was wandering around the "gulf of mexico" with my larger Dob last summer (late). Wonderful sight with an O-III filter in my 31mm 2" eyepiece. The whole nebula takes several FOV to fit it in.

Regards Steve

[Auntystatic]

The eyes pupil is at its largest between 7 and 8mm that's why 7x50 binoculars look so bright (50/7=7.14) anything wider spills light and is a waste.

[Adz]

Thank you all for your input, it is very helpful. Umadog and Steve your previous experience had definitely led me to trying out a 31 Nagler in my dob and the bigger one I will get in the future

I shall also keep the Pan 24 for many reasons, it is just too good!

I have added the north American nebula and rosette to my lists as well

[themos]

here's a stellarium view

[Adz]

Thanks Themos, how come my version doesn't show The Veil like that?

[Brent]

Thanks Themos, how come my version doesn't show The Veil like that?

I was thinking exactly the same thing.

EDIT: Found it http://stargazerslounge.com/discussions-software/160536-more-objects-stellarium.html

[themos]

it's because you haven't added these images to your stellarium installation

Nebula images - Stellarium Wiki