Under UK skies would 6.5mm find much use in my scope?

[JOC]

I already know that too much mag. overpowers my telescope under UK Skies.  I already know that things are close to ideal at 8mm.  I already know that I like the Baader Morpheus range.  They don't make a 8mm, would the 6.5mm overpower my kit if I saved my pennies?

[michael.h.f.wilkinson]

6.5mm is certainly not overkill in an F/6 scope. I go down to 7mm with my F/10 SCT (290x) on nights of good seeing, and regularly use the Pentax XW10 (203x) and Delos 8mm (254x).

[John]

If the seeing is good, the target is suitable and the scope is in reasonable collimation then I think 185x (6.5mm eyepiece) is well within the capabilities of the scope.

When I used to have a 200P dob I found 240x (5mm eyepiece) got quite a bit of use.

 

 

[billyharris72]

I'm not sure you would get a lot of use out of it for DSOs as the exit pupil is getting pretty small. In my f6 Dob I usually don't go below 12mm (x100) on DSOs. However, 6.5mm is still a reasonable exit, so it would find some use here. Would be a good eyepiece for lunar, planets and double stars. I've gone as low as 4mm (x300) with my Dob. That is pushing it (except on lunar, where it handles it easily) and uncomfortable (it's a Plossl). I find a 6mm eyepiece just about perfect in my scope for Jupiter, if the seeing is good.

If you already have an 8mm eyepiece (and it sounds like you do) then I would be inclined to buy another focal length anyway.

Hope this helps.

Billy.

[JOC]

11 minutes ago, billyharris72 said:

If you already have an 8mm eyepiece (and it sounds like you do)

I've experimented with a TV 8mm plossl and sold it because I found the eye relief made it unusable.  I've been experimenting and have got a 6mm TMB plantetary II clone on M13 and it seems OK and I've also got one of those in an 8mm, but I've been that impressed with my 15mm Morpheus that I wondered if buying another Morpheus would improve things beyond the TMB clone performance.  I know that an 8mm is about the right mark as my Meade 15mm super plossl + x2 Barlow does give me good views when-ever I use it, but the Morpheus doesn't come in an 8mm only a 9 mm and the 6.5mm.  I have the 10mm mark more or less covered, it's the lower end that I've got the TMB clones for that I wondered about improving.

[Astro Imp]

18 minutes ago, John said:

When I used to have a 200P dob I found 240x (5mm eyepiece) got quite a bit of use.

I have the same scope as you and as John says my 5mm gets a lot of use, especially for lunar. 

[Owmuchonomy]

I have an ES 4.7mm 82' (from the FLO sale) which gets use in my ED120 as described above for doubles and lunar.  My neighbour nearly fell over backwards when he split Algieba with it.  It is quite good for eye relief too, in fact I'd say better than the Baader Hyperion 10mm I sold on.  On Jupiter at its current altitude it was too much though.  I couldn't really get beyond the equivalent ES 14mm with a powermate 2x for the gas giant.  I have no experience of the 4.7 in anything faster though.

[MarsG76]

6.5mm should be fine, you might not get to use it as often as a lower power EP, but the rare clear nights when you do get to use it, you will be glad that you have it in you arsenal.

 

[triton1]

You could try barlowing your 11mm tv plossl or the 14mm Morpheus giving you 5.5 and 7 respectively this would give you a good idea what is capable of,in fact why buy another ep when you have a barlow?I often barlow my 5mm when looking at the moon.

Edited June 15, 2017 by triton1

[rockystar]

The 6.5 is reasonable in my scope (same as yours, just solid tube), and does get used without going overboard on magnification (double stars, some PNs, the moon and planets). You have a few more EPs than me, as my jump is from 14 to 6.5, and I find myself hankering after the 9mm quite often.

[Louis D]

1 hour ago, rockystar said:

You have a few more EPs than me, as my jump is from 14 to 6.5, and I find myself hankering after the 9mm quite often.

Give in to the dark side.  Get the 9mm Morpheus.  You know you want it.  Why resist? 

Seriously, I love my 10mm Delos.  It is basically perfect from edge to edge even without a coma corrector at f/6.

[rockystar]

1 hour ago, Louis D said:

Give in to the dark side.  Get the 9mm Morpheus.  You know you want it.  Why resist? 

Seriously, I love my 10mm Delos.  It is basically perfect from edge to edge even without a coma corrector at f/6.

don't you worry, it will be in my case before the end of the year - just need to save the moolah

 

[JOC]

On 2017-6-15 at 20:13, triton1 said:

in fact why buy another ep when you have a barlow?

Well I have tried my existing one in a Barlow, but the 'hand grenade' format in the Barlow isn't the safest feeling combination in the focus unit, I have also noticed that the telescope is prone to being off balance which affects how it drives if I get too much weight down one end too.  I do like what the Morpheus offers and really don't know whether just to enjoy my scope with what I already have or whether to keep buying more kit which I guess I can't really justify.

[John]

Barlows / Telextenders can put a lot of weight / height into the final part of the optical chain

 

This can come in handy though

 

Edited June 17, 2017 by John

[Charic]

If you take the focal ratio of your scope 1200/200= f/6 then an eyepiece of 6mm makes for a perfect match ( matches the focal ratio and aperture ? ) providing a practical 200x power that this scope is capable of providing under the right conditions, its when you try to get the theoretical powers of 'twice the aperture' do you suffer the consequences ?

The 6.5mm EP will be just fine. Its this method, using the focal ratio, that I suggest to folk when buying their first high powered eyepiece, and work from there, the next EP for this scope would be a 12mm. That said, the 12mm makes for a nice focal length on the same scope, its my sweet-spot! its twice the focal ratio, half the power, better detail, smaller image?

[LukeSkywatcher]

I dont think that 6.5mm under our skies in a 200mm scope is an unreasonable request. I am unfamiliar with the Morpheus, so have no idea about the eye relief. 

8mm for me is about as low as i go with any scope (on any object), but i have gone down to 6mm Celestron Omni (observing the Moon).

ONCE. 

May i suggest an 8mm Vixen NPL?

https://www.firstlightoptics.com/vixen-eyepieces/vixen-npl-eyepieces.html

It will/should work a treat with your scope and get much use. I swear by the Vixen NPL's (not that i am an expert in any way). They just seem to work great with every scope i have from my 100 quid travel scope right up to my 8" SCT.

 

[Mr niall]

You know... I'm just about to sell a Celestron Omni 6mm. I know its not perhaps in the calibre that you are talking about buying but its a good budget piece and only a few months old (I bought it for my refractor but then changed to a MAK and its too powerful for that). I'm looking for £12.50 including postage. It might be a cheap way to try out a 6mm and would be a keeper if it was ok I reckon. 

Just an idea though! If you are interested let me know in the next couple of days, if not I'll put it in the classifieds, no problem either way!

[JOC]

Mr niall I was trundling through posts and spotted that I appeared to have completely ignored your kind offer - the ignoring part wasn't intentional - I clearly just hadn't spotted your response - please accept my apologies and I hope you found a suitable home for your EP.