New diagonal or new eyepiece?

[Steve91]

Hi guys,

Not had my scope long but looking to upgrade either my diagonal or get a new eyepiece. I have been lent a couple of good 25mm eyepieces but the stock ones at the high power are not very clear. Also i've heard that the stock diagonals are not up to much either so which would be a better investment?

I was looking at this diagonal - http://www.firstlightoptics.com/diagonals/william-optics-125-carbon-fibre-dielectric-diagonal.html

Or maybe a mid-high powered BST eyepiece or simiar

Thanks

[homer]

I bought a diagonal from ioastronomy

http://www.hampshireastronomy.co.uk/product/altair-dielectric-diagonal-99-1-25-inch

This made a difference

[Tinker1947]

If a 2" will fit go with one as its then future proof and will provide a better image.....

http://stargazerslounge.com/topic/211750-125-vs-2-diagonal/

[Steve91]

If a 2" will fit go with one as its then future proof and will provide a better image.....

http://stargazerslounge.com/topic/211750-125-vs-2-diagonal

Hey,

Would any of my 1.25" eyepieces fit? Because if not it would be a no no for now as I can only really afford one or the other

[homer]

2"-1.25"  Eyepiece Adapter about £15

[homer]

you will also find a 2" diagonal will be more money 

http://www.hampshireastronomy.co.uk/product/altair-dielectric-diagonal-99-2-inch

[John]

Is there any point in fitting a 2" diagonal to the 127 Mak ?. The rear port is only about an inch in diameter so I'm not sure will not be able to make the most of 2" eyepieces, ie: the wider field of view that they deliver, as the port will be narrower than the field stop of the eyepieces.

[knobby]

Is there any point in fitting a 2" diagonal to the 127 Mak ?. The rear port is only about an inch in diameter so I'm not sure will not be able to make the most of 2" eyepieces, ie: the wider field of view that they deliver, as the port will be narrower than the field stop of the eyepieces.

I've seen a lot of debate on this... Usual consensus if opinion is that it works, to a degree... You'll get slightly wider field but possibly darker at the extreme edges

[Pig]

I would go for an eyepiece in this instance   as per John's opinion on the rear port

[Steve91]

I see what you're saying about the rear port, the Mak has a small FOV and theres only so much I would actually be able to see in a 2".

The thing is i can only really afford one or the other, which do you guys think would make the most noticable difference? Just t let you guys know what I already have - 9mm Stock Eyepiece (struggles in anything below average seeing), 25mm stock eyepiece, 25mm E-Lux Celestron and a Bresser 26mm Super Plossl (which Is excellent) and also a 2x barlow. And I am still using the stock Star diagonal which feels a little cheap but i'm not sure of its optical quality.

[Tinker1947]

Is there any point in fitting a 2" diagonal to the 127 Mak ?. The rear port is only about an inch in diameter so I'm not sure will not be able to make the most of 2" eyepieces, ie: the wider field of view that they deliver, as the port will be narrower than the field stop of the eyepieces.

I recommended a 2" more for being there when the scope gets upgraded although i didn't know about the small port size....On the will your 1.25 fit in a 2", they normally have a 2" - 1.25" adapter supplied in the box....

[sandyshaw]

My Skywatcher diagionals are pretty good, not realy worth upgrading before all the rest of the other peices that would be worth upgrading.

[sandyshaw]

I think it really is a difference between 95% transmission vs 99% transmission.

If you need that 4% transmission then the rest of your optic path must be perfect.

[ronin]

If it is only one, then the eyepiece, will show the greatest single improvement.

I assume that the 127 in question is a 127 Mak, the 9mm will be too close to the maximun possible.

Using the BST's as examples the 12mm or 15mm will be better, but not another 9mm.

The Celestron X-Cels come in the same and there are 12mm and 15mm plossls, Vixen NPL's.

Update the diagonal later.

[sandyshaw]

How much transmission does good flocking gain on average?

[Northern Soul man]

Hi Ya Steve, as John says, no real benefit to the diagonal upgrade, the only reason I would upgrade is to change the type of add ons - to say that the visual back and the top of the diagonal have little screws which tighten onto the EP and the diagonal, over time this can score the barrels of the EP and star diagonal when moving around the sky, so if your buying expensive EP'S, the barrels are going to get scratched - the same with the star diagonal - if your going to upgrade - choose the compression fit option with brass rings which "cup" the EP and diagonal as not to scratch your nice new add - ons.

Paul.

[Steve91]

If it is only one, then the eyepiece, will show the greatest single improvement.

I assume that the 127 in question is a 127 Mak, the 9mm will be too close to the maximun possible.

Using the BST's as examples the 12mm or 15mm will be better, but not another 9mm.

The Celestron X-Cels come in the same and there are 12mm and 15mm plossls, Vixen NPL's.

Update the diagonal later.

Thanks for the reply

I'm only heading towards the BST's because of a large amount of people on here saying how good they are for the price. I was recommended the Celestron X-Cels by a shop but i've not really heard much feedback on them. I was thinking of going for around say 16mm, as i've said I have 25mm EP's and i also have a 2X barlow which gives me some other options but i'm not sure how good my barlow is and if it affects the quality of the view.