Help Please GS 10" Dob - Page 4

janoskiss (Steve H) · #61 19-09-2005, 11:01 AM

Quote:

Originally Posted by captain3081

I got the two GS 9mm and 25mm, GS 2" 26mm, and series 500 12.5mm and 30mm
...
I think I will return my 30mm, and swap it for a 6.5mm

The GS 2" 26mm probably has a bigger true field of view that the 30mm 500 (and you probably don't need the 25mm GS either.) But if you can swap one or both of them for different focal lengths, I would go for a 15 and/or 20mm. The 6.5mm will be too short on eye relief to be comfortable and you won't get much use out of it.

Jupiter is low in the sky right now so it won't take more magnification than 100x (what you get with your 12.5mm). Venus is very bright and you best catch it early just after sunset when it's still relatively high in the sky. Also the blue rather than black sky background at twilight may make it easier on the eye. You can also try the Moon filter on Venus.

[1ponders] (Paul) · #62 19-09-2005, 11:04 AM

Keep your 30mm cap'n. You'll be glad you did when you finally find some faint fuzzies and nebs. Jupiter is not going to be looking its best atm as its only around 25 deg above the western horizon after the sun goes down. Lots of boiling atmosphere to look through.

I noticed you have "I got the two GS 9mm and 25mm, GS 2" 26mm, and series 500 12.5mm and 30mm." Now I'm not an eyepiece expert by a long shot (I like piccies).... but.... if you could swap the 12.5 mm for a 2X barlow your 25mm eyepiece will then double up as a 12.5mm eyepiece

. You would effectively then have all your prime eyepieces as well as a 15, a 12.5, and a 4.5. Its not a perfect solution but it will give you the chance to use what eyepieces you have until you're better able to decide what it is you REALLY need and then start spending some big money to get some better quality eyepieces.

You might be interested in one of these 40mm (eye relief is too long for my liking) http://www.iceinspace.com.au/forum/s...ead.php?t=4017 so with a barlow that wouuld add a 20mm to your quiver as well. Not trying to push 'em, just a thought.

davidpretorius · #63 19-09-2005, 11:10 AM

firstly, how did the focussing go with the moon, was it clear, the 9mm should have showed maybe turbulence like "heat waves"

Quote:

Originally Posted by captain3081

I managed a good view of the moon. Couldn't locate any nebs or galaxies (probably cause i still don't know what I'm doing).

The best nebula to cut your teeth on is Orion as you simply cant miss it. Very hard at the moment with the full moon, wait a few more days and you will start to see a big difference. I will be interested to see if you can see the milky way with the naked eye. If you can, then just following that along will give you great views thru any eyepiece.

Quote:

Originally Posted by captain3081

How big should venus look though 9mm plossl without barlow? It wasn't really big enough to make out any shape or phase. The diffractions lines were dominant.

Venus is very bright and without some filters i doubt you will see any details. Even the imaging guys have to work really really hard to get detail.

Quote:

Originally Posted by captain3081

Will Jupiter be a decent size through a 9mm without a barlow?

I think I will return my 30mm, and swap it for a 6.5mm

If you can catch it early enough in the evening, you may get to see the brown bands, but it is really too low now in the sky. Best to wait another month for saturn

Yes take it back, but the 6.5mm series 500 is amost useless. i have one, but hardly use it. It is hard to see thru (eye relief) I would either get money back, or as Janoskiss says, go the 15 or 20. When you get a barlow later, then that will turn the 12 into a 6 and the 15 into a 7mm.

You have picked the worst time of the month for viewing anything apart from the moon, but if you can get the moon into a sharp focus with all your eyepieces, then in a few weeks time hen there is no moon, look out!

captain3081 · #64 19-09-2005, 11:20 AM

Thanks for the encouragment everyone. I feel like less of a loser now.

The moon was very sharp will all the EPs. With 9mm, there were heat waves. It was an awesome sight. I read that the full moon is the worst. Better to look at a crescent moon for more contrast. Can't wait.

I have never seen the milky way with my naked eye. My backyard is full of light pollution. Last night, after my eyes adjusted, the moon was like a big torch!

I just can't wait to get that wow! experience. My wife could tell I was a little disappointed last night. I didn't realise that the conditions would have such a big impact.

You have all restored my faith. I will try and be a little patient.

To clarify, is 12.5mm with 2x barlow better than 6.5mm in terms of eye relief and fov, or is it exactly the same?

ving (David) · #65 19-09-2005, 11:20 AM

yeah, go practice forusing and such with the moon and some of the brighter stars. once the moons gone you'll be able to see a whole universe of objects

if you are getting a 6.5 go for the GSO, caue while mine gives good views of many objects i have heard too many bad reviews to recommend it. there are also some premium EPs for sale in this forum you might want to look at. dont be too afraid to buy second hand as most people look after thier gear really well

ving (David) · #66 19-09-2005, 11:22 AM

Quote:

Originally Posted by captain3081

To clarify, is 12.5mm with 2x barlow better than 6.5mm in terms of eye relief and fov, or is it exactly the same?

better eye relief. but you need to get a good barlow like an orion shorty to retain viewing quality

Starkler (Geoff) · #67 19-09-2005, 11:23 AM

Quote:

Originally Posted by janoskiss

The GS 2" 26mm probably has a bigger true field of view that the 30mm 500 (and you probably don't need the 25mm GS either.) But if you can swap one or both of them for different focal lengths, I would go for a 15 and/or 20mm. The 6.5mm will be too short on eye relief to be comfortable and you won't get much use out of it.

I used to own one of the 26mm GSO's and it was a shocker at f5.
Considering he already has a 12.5mm, the addition of a 15mm plus a good barlow gives two nice planetary magnifications. I dont know why GSO bundles a 9mm with these dobs IMO a 12mm would be much more useful

janoskiss (Steve H) · #68 19-09-2005, 11:26 AM

I'd have to disagree with Paul on using a barlowed 25mm instead of the 12.5mm. It won't be nowhere near as good, even through a good quality barlow. I know because I tried; uncomfortably sensitive to eye positioning, poorer contrast with noticable stray light and internal reflections.

As for the 30mm: compare the field of view of with that of the 2" 26mm. If the 30mm does not give you a wider field, then there is not much point keeping it.

Quote:

Originally Posted by davidpretorius

You have picked the worst time of the month for viewing anything apart from the moon...

The Moon will get out of the way before you know it and it is a great time of the year for deep sky. Galactic centre is approx straight up as soon as it starts getting dark.

Starkler (Geoff) · #69 19-09-2005, 11:27 AM

Quote:

Originally Posted by ving

better eye relief. but you need to get a good barlow like an orion shorty to retain viewing quality

Theres a lot of confusion, but its the Orion Shorty-PLUS which is the good one. The Orion Shorty is just another cheap Chinese barlow of mediocre quality.

janoskiss (Steve H) · #70 19-09-2005, 11:31 AM

Quote:

Originally Posted by Starkler

I used to own one of the 26mm GSO's and it was a shocker at f5.

Uh! So that's another thing to consider... You be the judge Captain! Have fun!

captain3081 · #71 19-09-2005, 11:35 AM

Where there is choice there is no clarity. It's all too hard.

It seems I have a month or two before I will be wanting more magnification. I will assess the finances at that stage.

Doesn't anybody else have any work to do?

[1ponders] (Paul) · #72 19-09-2005, 11:35 AM

That's alright Steve, disagree away

I'll catch you once you platform mount and motorise that dob of yours and are looking for imaging gear

janoskiss (Steve H) · #73 19-09-2005, 11:42 AM

No probs, Paul! Looking forward to it!

Starkler (Geoff) · #74 19-09-2005, 11:42 AM

Quote:

Originally Posted by captain3081

It seems I have a month or two before I will be wanting more magnification. I will assess the finances at that stage.

Doesn't anybody else have any work to do?

I remember when Mars madness hit last time around, short focal length eyepieces and barlows couldnt be had for love nor money as the retailers were all out of stock

It pays to forward plan as just when you need something in a hurry, nobody seems to have any

P.S. Im having a day off

davidpretorius · #75 19-09-2005, 11:44 AM

captain, if the weather is nice over the next week, give me a quick bell.

i recommend http://www.skyviewcafe.com/skyview.php

set up your latitude and longitude, and you can a very good feel for what is around and when. it will make it great to find m8 (the lagoon nebula), m6 & m7 (clusters)

have a good play with this when the weather is bad and familiarise yourself with m6/m7/m8 patch of sky. stay small at the moment, so that you should be able to recognise this area nice and quickly. Remember that when you go to look thru the scope, everything will be upside down and back the front!

ving (David) · #76 19-09-2005, 11:48 AM

Quote:

Originally Posted by Starkler

Theres a lot of confusion, but its the Orion Shorty-PLUS which is the good one. The Orion Shorty is just another cheap Chinese barlow of mediocre quality.

D'oh! my bad

not a big fan of barlows anyhow. but then my one is a cheapie and i have none to compare it to.

and once the moon goes captian, pack your dobbie into a car and get yourself to some dark skies!

dark skies make a huge difference

captain3081 · #77 19-09-2005, 12:02 PM

Quote:

Originally Posted by davidpretorius

i recommend http://www.skyviewcafe.com/skyview.php

I use skyglobe and stellarium. Is it the same thing?

davidpretorius · #78 19-09-2005, 12:19 PM

skyview is an online one, but i have not tried those ones. i also now use starry night pro.

janoskiss (Steve H) · #79 19-09-2005, 01:38 PM

Stellarium is not much more than a toy at this stage, unfortunately. It looks great but it needs to include a lot more objects to be useful. Don't know about Skyglobe but it may also be lacking. I use Kstars and Xephem but these are Linux/Unix programs. Cartes du Ciel seems to be the one to get for Windows, if you want a more capable free planetarium program.

Roger Davis · #80 21-09-2005, 12:41 PM

See my article on Teflon pads and Armorall! Use Armorall and cure 80% of your woes, use Armourall and Ebony Star Formica and cure 99.9% of them! The central teflon pad eases the pressure on the outer pads and makes the rotation easier. If you don't have a central pivot pad, you can use milk bottle washers, or go to Bunnings and buy a couple of teflon plumbing washers. Clean your melamine bearing surface area with the Armourall then go observe.