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View Full Version here: : Lens advice - 1st Dobson scope


Tasaurora
03-06-2020, 02:47 PM
Hello all,

I’ve bitten the bullet and ordered a sky watcher 10” Dobson with GOTO capability.
This scope is a step up from the couple of $99 Kmart crap the kids have been using and will hopefully inspire my kids to get off their PC’s.

Anyway - whilst awaiting delivery, I’ve been wondering what might be the best lenses to have on hand to ensure the kids get their best viewing experience from the off ?
The scope comes with a 10mm and a 20 and is 2” compatible - would a 2” 2x Barlow be worth adding in ? I don’t want to end up with 10 lenses and I want my kids (aged 9-15) to be able to utilise without getting lost in lense variability.

The scope initially will be used to view planets - next couple months, Jupiter in particular looks to be coming close.

Open to any and all suggestions.

Thanks.

david booth
03-06-2020, 04:12 PM
a 2 times barlow is a good start

Tulloch
03-06-2020, 04:37 PM
Agree with the 2x Barlow, and while the Plossl eyepieces that came with your scope work, I would recommend something a little better for the planets, such as one of these. 6 mm gets you a good look at the planets and their moons, 3 mm (using a 2x Barlow) gets you nice and close when conditions allow.

https://www.bintel.com.au/product/orion-edge-on-planetary-eyepieces-1-25-inch/?v=322b26af01d5
https://www.opticscentral.com.au/saxon-cielo-hd-6-5mm-1-25-ed-eyepieces.html

This is a good website to estimate what you will be able to see with your scope/eyepiece combination.
http://www.12dstring.me.uk/fovcalc.php

Andrew

Saturnine
03-06-2020, 06:18 PM
Hi

Personally I would recommend getting a good quality 2" wide angle eyepiece for viewing clusters and nebulae, even the Skywatcher 28mm is quite good value. That paired with something like the GSO 2" ED Barlow will give you a good range of magnifications, the 10mm that comes with the scope when paired with the barlow will give you 240X magnification which is good enough to show you detail on the planets that should keep everyone engaged for a while and give you time to learn the scope and better figure out what you may want to upgrade to in the future.

Scorpius51
03-06-2020, 07:03 PM
I agree with what the guys have been suggesting. A good quality x2 ED Barlow and a selection of at least 3-4 good quality 2” lenses from around 5mm to 30mm. That’s essentially what I use with my 10” Dob and 8” Newtonian. This range gives you a good choice of magnifications and fields. I’m assuming that your 10” Dob is around f/5.

Tasaurora
03-06-2020, 07:07 PM
Thank you all for advice - duly noted.
I’ve contacted the scope supplier asking for a few prices on the recommendations given above. Looking forward to receiving scope and setting it up. Thanks Si.

m11
03-06-2020, 07:18 PM
Hi Si,

I recommend for the next step up and good bang for buck would be the 82 degrees Explorer scientific for wider eyepieces.

I like the orthoscopic eyepieces for the moon and planets which are not too expensive.

AstroJunk
03-06-2020, 10:37 PM
Awesome scope, great choice :)

Maybe you can beef up the quality of your ~10mm. 125x and upto 150x magnification is really useful for all round viewing and a nice wide angle eyepiece will be fabulous. Older 9mm Naglers come and go for 300-350 bucks in the classifieds and they are (ironically) keepers. You need some more power for the planets, but that's where logic gets turned upside down a bit. Simple and relatively cheap eyepieces can do extremely well on planets because you are looking on-axis and don't need a wide field of view. A 4mm or 5mm would probably be enough.

If you can, hook up with a club and try before you buy, you will get priceless advice from the regulars!

Tasaurora
04-06-2020, 04:10 AM
Cheers again for advice.
I made 3 appointments for public interest days with the local astronomy club and every night I booked in was cancelled due to cloud lol. So kids were hyped to go and have a look and then shot down - This is one reason I’ve decided to buy something that hopefully will allow them to see planets in reality...I’m hoping they will get inspired and just sitting with them last few nights and explaining distances etc - it’s hard for them to get their heads around...me too. I’m also trying to manage expectations as I know they are looking at space telescope videos and co - another reason for lens upgrade.
We are having insanely clear nights of late and I have access to a property at in the absolute middle of no where with very tall hills all around blocking light pollution - so can’t wait now.