Sky-Watcher Stargate 450P Synscan

[FLO]

We have put aside a Sky-Watcher Stargate 450P Synscan 18" GOTO Dobsonian for star parties and astronomy outreach. 

If FLO is at a star party or observing event then this telescope will likely be there too. You are welcome to come enjoy the views ? 

(Apologies for the basic stock photo, we'll make our own soon).

 

[FLO]

Now we must choose a set of Tele Vue eyepieces to go with it... ? 

Any suggestions? 

[Grant]

You get extra points if you suggest a 21mm Ethos as one of these is definitely winking at me!

[FLO]

?

[Spikey]

Might be worth taking various brands of EP so comparisons can be made based on budgets ?

[FLO]

1 minute ago, Spikey said:

Might be worth taking various brands of EP so comparisons can be made based on budgets ?

This is FLO's first large Dob (a member of the Dob' Mob!) so we want to push the boat out, and that requires Tele-Vue ?

But I think you are right. We should also have a set of more affordable eyepieces to hand. Perhaps some BST Starguiders, Celestron XCel-LX or Baader Morpheus. And of course if someone wants to compare their eyepieces with ours then they'll be welcome. 

[Trikeflyer]

Can't wait to have a look through this at SGL star party.  Thanks for giving the community the opportunity to experience this monster.

I think you've got the eyepiece choice covered in the previous two posts. +1 for the range of price options and not just the top end choices 

 

[FLO]

52 minutes ago, FLO said:

This is FLO's first large Dob (a member of the Dob' Mob!)

Is it still necessary to grow a beard... ? ?

Or is that now more a refractor thing (thinking @John & @F15Rules) ?

[Beulah]

Sorry to be boring but the TeleVue Plossls and the Explore Scientific 82 degree EPs are VERY good with the Skywatcher Dobsonians, having owned four dobs over the years and still using 3 on a regular basis.

 

[clarkpm4242]

Nice one.

For deep sky

31mm Nagler

13mm Ethos

Optional Paracorr

Al Nagler recommended this combo

Cheers 

 

[DRT]

6 hours ago, Grant said:

You get extra points if you suggest a 21mm Ethos as one of these is definitely winking at me!

I can heartily recommend a 21mm Ethos as being the ideal eyepiece to pair with a large Dob  

Go on Grant, you know you're worth it ? 

[D Wright]

I have the same scope and use the 31mm and 17mm Nagler and they both perform very well. Personally I don't find that I need a Parracor. Saying that I am sure if I tried one I would want it.

[Grant]

I quite like this setup combination:

https://goo.gl/Z9PzRL

[estwing]

Only need the 21 and 8mm ethos in a 18" for the wow factor....even better if the skies clear!.. Surely people could pop their own ex's in?

[alanjgreen]

16 minutes ago, estwing said:

Only need the 21 and 8mm ethos in a 18" for the wow factor....even better if the skies clear!.. Surely people could pop their own ex's in?

Agreed, your EP set has to include an 8mm Ethos to show the extra magnification capabilities of a large mirror

[Grant]

So maybe something like this?

https://goo.gl/Vm38qb

[estwing]

It's an absolute killer in a 18" mirror...like the 13E in a 22"

[Grant]

So:

Nagler 31mm

Ethos 21mm

Nagler 16mm

Nagler 11mm

Ethos 8mm

Nagler 7mm

plus Paracorr?

That’s a couple more than I had originally planned but gives a wide spread but it is more than is necessary?

 

[alanjgreen]

On first sight the 11mm Nagler seems redundant, the 8mm Ethos usurps it!

The list will let people compare/contrast 100 degree with 82 degree? Perhaps you need a 72 degree Delos in your kit instead of a similar Nagler?

- replace the 16 nagler with a 17.3 delos?

- replace the 11 nagler with a 12 delos?

 

[Grant]

5 minutes ago, alanjgreen said:

On first sight the 11mm Nagler seems redundant, the 8mm Ethos usurps it!

The list will let people compare/contrast 100 degree with 82 degree? Perhaps you need a 72 degree Delos in your kit instead of a similar Nagler?

- replace the 16 nagler with a 17.3 delos?

- replace the 11 nagler with a 12 delos?

 

In terms of FOV, they do look close but the magnifications are quite different, that setup would give me (ignoring the effects the paracorr will make to focal length):

Nagler 31mm - 61x / 7.5mm exit pupil

Ethos 21mm - 90x / 5mm exit pupil

Nagler 16mm - 119x / 3.9mm exit pupil

Nagler 11mm - 173x / 2.7mm exit pupil

Ethos 8mm - 238x / 1.9mm exit pupil

Nagler 7mm - 271x / 1.7mm exit pupil

 

It might be as you say, that in practice / use the Ethos becomes the favoured option and the Nagler 11mm becomes superfluous. It might also be that the 7mm isn't needed and I will use my Hyperion zoom / barlow for higher magnification use, at least to begin with.

I also wander how much I would use the Nagler 31mm in practice? There are a few targets I would like to try it on, and it's probably useful as a finder eyepiece but beyond that, how much use would it get?

 

 

 

[Grant]

Here's the simulation swapping in some Delos:

https://goo.gl/PwDPYj

[alanjgreen]

24 minutes ago, Grant said:

I also wander how much I would use the Nagler 31mm in practice? There are a few targets I would like to try it on, and it's probably useful as a finder eyepiece but beyond that, how much use would it get?

Yep, I sold my Nagler 31mm when I got the 21mm Ethos. There are a couple of targets such as the Veil where the extra sky would be nice but the darker background of the 21mm is really nice and really shows its worth on Leo & Virgo galaxy groups in the winter months.  No way I could keep them both in my case - just too much money not being used

[Grant]

1 hour ago, alanjgreen said:

Yep, I sold my Nagler 31mm when I got the 21mm Ethos. There are a couple of targets such as the Veil where the extra sky would be nice but the darker background of the 21mm is really nice and really shows its worth on Leo & Virgo galaxy groups in the winter months.  No way I could keep them both in my case - just too much money not being used

Do you use anything with less magnification than the 21mm Ethos?

[alanjgreen]

1 hour ago, Grant said:

Do you use anything with less magnification than the 21mm Ethos?

No. My scope is f3.6 (f4.1 with paracorr2) and the exit pupil would be too much.

[estwing]

2 hours ago, alanjgreen said:

Yep, I sold my Nagler 31mm when I got the 21mm Ethos. There are a couple of targets such as the Veil where the extra sky would be nice but the darker background of the 21mm is really nice and really shows its worth on Leo & Virgo galaxy groups in the winter months.  No way I could keep them both in my case - just too much money not being used

Always wanted the 31 until I looked through swampthings...21 kills it...and please don't start the " I like to fit the whole thing in stuff"....get imersed!