time line for ep's

[davidpretorius]

for a 10" or 12" dob, is this the best order for working thru buying your ep's:

1. 9mm,15mm,20mm,25mm GSO's & cheshire for collimating bought when you buy your scope
2. barlows & wideviews.

can you see thru a cheshire, or is it simply a collimation tool?

I spose i was wondering what next to budget for in a specialised eyepiece ie barlow 1" or 2" and extra wides etc

[elusiver]

u can't observe through a cheshire.. u can see through it.. but just for when u'r collimating.

i've only just got my dob and am pretty much following that order.... got the 9, 25 and cheshire when i got the scope.. then bought the 15 and barlow. Now i'm looking at the 20mm superview

el

[davidpretorius]

Originally Posted by elusiver

then bought the 15 and barlow. Now i'm looking at the 20mm superview

el

thanks,

which barlow? and what is the main reason for barlow's and superviews

[elusiver]

barlows basically double u'r ep collection. U get 2x from any eyepiece.. so the 20mm turns into a 10mm etc etc, although you do get a little loss in 'quality' when barlowing. So bascially with my 9, 15 and 25mm ep's i've got a 4.5, 7.5 and 12.5mm as well if i barlow them. I got the gso short barlow.. cause.. it's cheap.. and.. it's cheap. As a n00b spending big bucks on ep's at at the mo not really on the agenda. But if u did want to spend abit more the orion shorty plus is the way to go for around $150.. then after that if u wanna spend more look at the televue powermate.. big bucks but from what i've read are freakin awesome.

superviews give u a wider apparent fov, so you it's great for open clusters etc so u can fit more in, i think.. never looked through one.. so don't know for sure.. but this is just going by what i understand. But they basically make observing heaps more pleasant.

el

[ving (David)]

superviews are gret for dob users... because we dont have tracking we have to keep nudging the scope. with a superview it takes longer for the object to go thru the increased FOV = less nudging.
I hae 2:
2" 30mm sv
1.25" 15mm sv

[rmcpb (Rob)]

If you are getting a barlow make sure its a good one like the Celestron Optima or the Orion Shorty Plus, they are the same barlow just different badges. Both are fully apochromatic and, as a result, will give better images through the eyepiece and will be a far reaching investment.

A couple of points about optics:
- get the best you can afford and,
- take your time as they are expensive and you need to know why you are buying the eyepiece so you get the right one.

Cheers

[davidpretorius]

Ok thanks to all, shopping list is now:

1. 9mm,15mm,20mm,25mm GSO's (does the 'O' stand for optics in Guan Sheng Optics????)
2. cheshire for collimating
3. Would these "Andrews 80° Ultrawide (UW) Eyepieces" suit the 10" or 12" dob? and if I have a 15mm superwide, do i really need a 15mm GSO from the set of 4 above?<TABLE class=content cellSpacing=0 cellPadding=2 border=1><TBODY><TR class=tbl_text><TD class=desc>Outstanding 2" 80 [degrees] 30mm f.l. eyepiece.</TD><TD class=price>$149.00 Each</TD></TR><TR class=tbl_text><TD class=desc>NEW 2" 80 [degrees] 15mm f.l. eyepiece, available soon</TD><TD class=price>$149.00 Each</TD></TR></TBODY></TABLE>
4. barlow - orion shorty plus

[davidpretorius]

Ok thanks to all, shopping list is now:

1. 9mm,15mm,20mm,25mm GSO's (does the 'O' stand for optics in Guan Sheng Optics????)
2. cheshire for collimating
3. Would these "Andrews 80° Ultrawide (UW) Eyepieces" suit the 10" or 12" dob? and if I have a 15mm superwide, do i really need a 15mm GSO from the set of 4 above?<TABLE class=content cellSpacing=0 cellPadding=2 border=1><TBODY><TR class=tbl_text><TD class=desc>Outstanding 2" 80 [degrees] 30mm f.l. eyepiece.</TD><TD class=price>$149.00 Each</TD></TR><TR class=tbl_text><TD class=desc>NEW 2" 80 [degrees] 15mm f.l. eyepiece, available soon</TD><TD class=price>$149.00 Each</TD></TR></TBODY></TABLE>
4. barlow - orion shorty plus

[asimov (John)]

Dont forget to order the cheshire with cross-hair's David. (although they probably come standard these days, not sure?) The cross hairs help centre your secondary under the focuser, instead of spending more buck's getting a sight tube.

The barlow I ended up with is the Meade series 4000 2X apochromatic telenegative amplifier. I cant compare it to anything else...but it doe's a marvellous job.

[asimov (John)]

And may I suggest you look at this before you order EPs...

http://www.aoe.com.au/eyepieces.html

[janoskiss (Steve H)]

Originally Posted by ving

superviews are gret for dob users... because we dont have tracking we have to keep nudging the scope. with a superview it takes longer for the object to go thru the increased FOV = less nudging.

I disagree. I don't like that the full field is not sharp, and seagulls around the edges. I still have to nudge as much as with a plossl because the usable field of the superview is no greater than the plossl. Yes, it does give you a bit more of a floating-in-space feeling, but only pleasant when you're looking at the centre of the field of view, so the blurry seagulls near the edge are in the peripheral.

Dave, If you're going to get one, get only one, and see how you like it.

Originally Posted by davidpretorius

Would these "Andrews 80° Ultrawide (UW) Eyepieces" suit the 10" or 12" dob?

Don't be tempted by the UWs. Not recommended for fast scopes. See this review on our very own Iceinspace.

Sirius Optics have the Shorty-Plus for $135, and Bintel dropped their price to $139 as well since I pointed it out to them. (Bintel did sell me one for $135, but they charged me $4 over the online price of the camera adapter I bought at the same time, cheeky buggers.)

[elusiver]

also.. check out this

http://www.iceinspace.com.au/forum/s...ead.php?t=2644

andrews prices have changed also.

el

[mch62 (Mark)]

In an f5 the 30mm super view will show flared stars towards the outter 25% of the view.
This is as a result of both Newtonian mirror coma and eyepiece abberations .
As there only a 5 element there not as well corrected for a fast f5 scope.
There fine for a f10. Resonable for f7.5

I would say stick with plossels as the only alternative for sharp images right to the edge of field will cost you more than the scope for one eyepiece.

Try before you buy as you may find the Andrews 30mm 80deg ok for your tastes. every body have different expectations and you may be able to live with it.

[Starkler (Geoff)]

Cheap widefield eyepieces are poor performers in fast scopes such as the GSO dob. I strongly recommend forgetting all thoughts of panoptic or nagler performance at a budget price. It just doesnt happen. What you usually get is a smallish usuable field no bigger than that of the plossl, surrounded by seaguls.

If you want to do things on a budget I would recommend the following.

Orion shorty plus
12.5mm plossl
15mm plossl
20mm plossl
and either a 30-32mm plossl or a 30mm GSO superview.

The 12.5 and 15mm plossls are good for general dso work and give you two very useful magnifications when barlowed for planetary viewing.

Plossls much shorter than the 12.5 become uncomfortable to view through due to short eye relief.

[asimov (John)]

My GSO 30mm SV 2" in my F/5 reflector is only just acceptable...As Geoff & a few other's have said...don't bother. Now in my F/8 refractor it doe's more than an acceptable job, due to it's longer focal length.

My best wide-view EP in 1.25" format is the celestron 24mm.

Your choice of 9mm 15mm 25mm (in 1.25" format) plus a good quality barlow is really all you need for now. Ignore everything else! LOL

[davidpretorius]

thank a heap.


4 good plossels and a cheshire it is, a good barlow later and a partridge in a pear tree.

i can't see a cheshire on andrews website, is it listed as something else?

[janoskiss (Steve H)]

Andrews has the Cheshires for $29 a pop. I know cos I just ordered one. To save further delays just include one with your order. (No I don't work for him. ...and iceinspace.com.au is not a subsidiary of Andrews Comm. )

PS. I've had my scope for 6 months and it took me that long (along with some $$ spent on the wrong things) to learn the information contained in this single thread.

[ballaratdragons (Ken)]

Everyone has differing reports on all sorts of stuff.

I have the GS 2" 30mm SuperView and after letting it cool for as long as the scope, I don't get seagulls around the edge! It is brilliant for large open star clusters and BIG nebs like Orion. The Carina section of the Milky Way looks magic through it. It is also a galaxy magnet!!

May I recommend (dollars permitting) getting a 2" Barlow. Then you can Barlow any EP, as the 2" has a 1.25" adaptor.

If dollars are short the Andrews 2" 2x Barlow is only $79. It isn't the finest peice of equipment made but mine works fine.

Andrews do have the $29 Cheshire, but they are not on his site.

[asimov (John)]

Why in the hell didn't I think of that! DERR! Take that on board David! About the 2" Barlow. In hind-sight, that"s what I should have done.

I never even considered 2" format when I kitted myself out. Now that I have one 2" EP human nature force's one to eventually get a 2" barlow giving you in effect 2X2" EPs! ( that's how I justify it to my wife, LOL... it's HUMAN nature, my dear!)

That's the best advice Iv'e heard all day Ken

You might be shelling out a few more buck's for the 2" over the 1.25" David, but It'll save what I & probably other's have done.......& end up with two different size barlow's! Just my 2 cents worth (plus GST) anyway.

PS Ken....How come U dont get them seagull's!?

[ballaratdragons (Ken)]

John,

It's coz I let the 2" sit in the cold just like the scope does and after about 1 hour of cooling the seagulls have flown away. Maybe because it's a big mother of an EP it needs cooling just like a scope!??!