Optics

[modelman1968]

I've got a Skywatcher 130 A-Z, which came with the very basic of lenses, although it does have a Barlow included. What would you guys recommend I buy for looking at the planets and moons? What would be the minimum lens for deep sky objects?

[John]

I think they come with a 10mm and a 25mm supplied so you could add a 32mm for low power, wide angle viewing and perhaps a replacement 10mm as thats the worst of the supplied ones - your barlow lens will make that a 5mm which should give you a reasonable range. Plossls would be an improvement over the supplied eyepieces but you can get better than that if you have the budget of course.

Deep sky objects are generally viewed at low to meduim power so the 32mm, 25mm and sometimes the 10mm for the smaller DSO's (Deep Sky Objects).

[great_bear]

Ah but the problem is John, that the Barlow that comes with that scope (unless things have changed) is not the "deluxe" model. It's the standard one which is a single glass lens without coatings.

Use of that Barlow will render even a respectable 10mm eyepiece into something not much better than the supplied one.

I find a 32mm in that scope too much, and wouldn't recommend going longer than 26mm at most.

modelman1968 will need to make a basic choice as to whether you want to have eyepieces + a new Barlow (sometimes economical), or just get eyepieces that are the lengths you like (least hassle).

Which would you prefer, modelman1968?

(personally, I prefer not to use Barlows)

[modelman1968]

I'd rather not mess around with changing eyepieces too often, especially as I live in Norway, and so changing lenses is a painfully cold affair. Having said that money is a motivator, so I'll have to see what I can afford. Realy interesting comments on the low quality Barlow, maybe I'll see if I can borrow a better quality one and see what the difference is.

[John]

Ah but the problem is John, that the Barlow that comes with that scope (unless things have changed) is not the "deluxe" model. It's the standard one which is a single glass lens without coatings....

Ah, yes I'd forgotten that Skywatcher include that awful piece of kit with some of their scopes

[modelman1968]

Well, I guess it was enough to get me hooked, now I'll have to spend some proper money. ;-)

[great_bear]

You could get by very well on just these three:

• The 4mm TMB Designed Planetary (£36) will provide the maximum sharp magnification in your scope
  
• The 9mm Sky-Watcher Ultrawide (£29) provides excellent mid-power views
  
• The 24mm Meade SWA (£130 or less) provides the maximum wide-field views from your scope
  

The first one should be the top-priority, since you'll not get good planetary views by using the supplied budget barlow on the 10mm Super supplied with the scope.

The last one is expensive, but there are no cheap 24mm widefields that work well in F5 scopes.

The above eyepieces will provide you with magnifications of 163x, 72x and 27x respectively.

[modelman1968]

That's great information Great Bear! Thanks for taking the time to break that down for me, and put in such a way that even a newbie like me can understand.

I'll definately invest in the 9mm and probably put the others on my Chrimbo list for the wife - anyone know a good flower shop?

[michael.h.f.wilkinson]

You could get by very well on just these three:

• The 4mm TMB Designed Planetary (£36) will provide the maximum sharp magnification in your scope
  
• The 9mm Sky-Watcher Ultrawide (£29) provides excellent mid-power views
  
• The 24mm Meade SWA (£130 or less) provides the maximum wide-field views from your scope
  

The first one should be the top-priority, since you'll not get good planetary views by using the supplied budget barlow on the 10mm Super supplied with the scope.

The last one is expensive, but there are no cheap 24mm widefields that work well in F5 scopes.

The above eyepieces will provide you with magnifications of 163x, 72x and 27x respectively.

Spot on! You could consider the Baader Hyperion 24mm: a bit cheaper than the Meade SWA, and also good. If you can afford the SWA, go for it.