Eyepiece advice

[Norfolk star gazer]

I seem to be buying a lot of EPs recently and then thinking maybe I should have thought it through.

My dilemma is that I want a 4mm for planetery (about the limit for my scope) and a decent 10 for DSO, but already have decent 5 (so no point in getting 10 and barlowing to a 5)

Would I be better off getting a 9mm and Barlow to a 4.5 or an 8 and Barlow to a 4?

Would an 8 be worth getting considering I already have a 7.

[miguel87]

If you have decent 5mm i doubt you woukd enjoy the view any more through a 4mm.

What is the focal length of your scope?

[Norfolk star gazer]

If you have decent 5mm i doubt you woukd enjoy the view any more through a 4mm.

What is the focal length of your scope?

Focal length is 1200. I was looking at Jupiter sunday morning with a 7 (barlowed to a 3.5) but it was a bit much mag and my 5 was not enough, so I though a 4 would be a good bet.

if there isn't much difference between a 4 and a 5, then would you suggest a 9 / 4.5 or a 10 as I don't have anything decent between a 7 and my decent 25!

Just trying to get a wide range for all types of viewing.

[miguel87]

5mm gives you 240x magnification. 4mm would give you 300x. 25% bigger, i guess it could be significant but nit majorly.

To be honest i like to cover a range of magnifications with minimum eyepieces. If you have a good 25 that will barlow to 12.5; i think a reasonable spacer between 25 and 7.

You have a 2.5mm 3.5mm, 5mm, 7mm, 12.5mm, 25mm.

Is your barlow of decent quality?

Cant see too many gaps really.

[miguel87]

Also you say a decent 10mm for DSO?

Personally speaking i would use a significantly lower magnification to view DSOs (other than planetaries or globulars).

I guess a 9mm would fill a minir gap. What objects would you find yourself using it on?

[John]

I reckon you will get a sharper and more contrasty view of Jupiter at 180x - 220x. It does not benefit from really high magnifications as well as, say, Saturn or Mars do.

I agree with the above poster that for deep sky objects eyepieces covering the 30mm - 15mm range would be very useful. The 10mm would be good for the more compact DSO's such as planetary nebula and for close up views of globular clusters.

[Norfolk star gazer]

The 2x Barlow came with the scope, so probably basic, but I also have a 3x as well (from Altair Astro) so most likely a good one.

To add more to the mix, I also have a good 27 and 32, so 2 x barlowed will make them a 13.5 & 16 and the 3x makes them 9 and 10.66, so overall I probably do have a good spread already.

I have mainly been looking at planets so far, but want to move to DSOs and not sure what I would need. I will need to make a list of what I have.

[bomberbaz]

I think you need a couple of decent wide angle eyepiece imho. One around the 30/32mm mark and another at 20/21mm with 70 degree-ish or so fields of view.

These will give you some cracking views of larger DSO and star clusters. M42 looks amazing in my 21mm SWA eyepiece under good skies. The 30mm-ish sized one would also be a great finder eyepiece.

Steve

[Norfolk star gazer]

My 32 has a 50 FOV and the 27 is 53 FOV.

[bomberbaz]

That will be down to the design of your EP's. My 22 is 70 and the 30 is a 80. These give much greater views anda space walk feel when viewing.

Steve

[John]

A 32mm eyepiece with a 50 degree field of view is a good one to use for deep sky objects. With the larger objects it may be all you want. With the smaller ones, you can "find" them with the 32mm and then add a little more magnification to frame the object nicely.

[bingevader]

I like a range of EPs at short focal lengths, Barlowed or otherwise.

I know there are people who say they can manage with 3 EPs in total, but I imagine their observing conditions must always be crystal clear and perfect.

Things vary so much here, that it's always good to have the ability to drop back or step it up when necessary, or possible.

The difference in magnification is also much greater with the small steps in focal length at that end too.

My long winded reason for stating this is that, yes I have observed Jupiter with an 8mm EP and a 2x Barlow with a 1200mm 'scope and, my goodness, yes it was worth it.

It's only happened once so far, but I'm glad I had the opportunity and ability to do it.

The image drifted in and out of clarity, but the periods of clearness were jaw dropping at the extra magnification.

To be honest, the drifting in and out was what I'd been used to observing with the 6mm over the previous couple of weeks, so to experience the same, but with extra magnification was marvellous.

[F15Rules]

I'd agree with the earlier poster who advised making a list (and sharing it here if you welcome advice- which I'm sure will be very readily offered).. In fact, the more info you can share the better the advice you will probably get, as the make, type and focal length of your scope will affect the types of advice you need. So, in summary, I'd suggest you list:

Make, type,model and focal length of your scope.

Make, model and focal length of your current eyepieces.

An idea of your maximum budget?

Can you sell any of your existing eyepieces to help fund others? In general I would rather have 3 or 4 decent eyepieces at well spaced focal lengths than 7 or 8 so so ones.

Hope that helps.

Dave

[Norfolk star gazer]

Dave

My scope is a 10" skywatcher with a focal length of 1200mm.

EPs

5mm Altair Lightwave LER flat field (55 FOV)

7mm. Celestron x-cel LX

10mm unbranded super 10 that cam with the scope

25mm unbranded star guider

27mm BST Flat (53 FOV)

32 unbranded plossl (50 FOV)

I also have a really cheap set (Less than a £10) and that has a 4, 8, 12.5 & 20.

2 x Barlow (celestron)

3 x Barlow (Altair ED)

I have worked out that by using the 2 x Barlow with what I would consider to be the good EPs (5, 7, 25, 27 & 32) that I have.

2.5

3.5

5

7

12.5

13.5

16

25

27

32

With the 3 x

1.67

2.33

8.33

9

10.67

With the 2 + 3 Barlow together (not sure if advisable)

Only the 25, 27 & 32 would worth being barlowed and would give.

5

5.4

6.4

So probably not worth it.

I summary, I guess i have a good range already, but thought that unbarlowed EPs were best, or is that not much difference?

Maybe a decent 20mm (70 FOV) would fill the gap between 16 and 25 and if barlowed to a 10 would fit between 7 and 12.5?

If I do need to buy some more, then I would prefer to spend less than £60 per EP.

I could sell some if required I guess.

[bomberbaz]

I have just the thing for you. http://www.firstlightoptics.com/william-optics-eyepieces/william-optics-swan-eyepiece.html

20mm-72 deg fov - £59.

Your scope though at F4.8 would meanit would lose some sharpness around the edges but I guess you already know that.

Steve

[Norfolk star gazer]

I haven't looked at that brand before. Something to consider

[bomberbaz]

I haven't looked at that brand before. Something to consider

William Optics eyepieces are decent. I own the SPL 6mm and I have to say its a little cracker. I was looking at the moon through it last night (x240) and it gave superb views. 

Dave

My scope is a 10" skywatcher with a focal length of 1200mm.

EPs

5mm Altair Lightwave LER flat field (55 FOV)

7mm. Celestron x-cel LX

10mm unbranded super 10 that cam with the scope

25mm unbranded star guider

27mm BST Flat (53 FOV)

32 unbranded plossl (50 FOV)

I also have a really cheap set (Less than a £10) and that has a 4, 8, 12.5 & 20.

2 x Barlow (celestron)

3 x Barlow (Altair ED)

I have worked out that by using the 2 x Barlow with what I would consider to be the good EPs (5, 7, 25, 27 & 32) that I have.

2.5

3.5

5

7

12.5

13.5

16

25

27

32

With the 3 x

1.67

2.33

8.33

9

10.67

With the 2 + 3 Barlow together (not sure if advisable)

Only the 25, 27 & 32 would worth being barlowed and would give.

5

5.4

6.4

So probably not worth it.

I summary, I guess i have a good range already, but thought that unbarlowed EPs were best, or is that not much difference?

Maybe a decent 20mm (70 FOV) would fill the gap between 16 and 25 and if barlowed to a 10 would fit between 7 and 12.5?

If I do need to buy some more, then I would prefer to spend less than £60 per EP.

I could sell some if required I guess.

Anyway, given these comments what more d'ya want   

[Norfolk star gazer]

Anyway, given these comments what more d'ya want

I will see how much I have in my account