Orion optics spx scopes

[vince 66]

After my latest planned purchase falling through I am looking for a faster scope than my m615 for dso's and somthing with more power than my megrez 90 but it must still be portable for star parties etc.I have noticed a couple of OO spx 200 newtonians for sale on buy and sell has anyone on this forum had experiance of these scopes the oo description seems to be high spec with 1/8 wave optics as standerd so Iam getting tempted but I am sure I've read somwhere that certain eye pieces won't work properly with fast scopes is this correct. The ep's I have are WO Uwans a couple of pentax xw's and a set of BGO'S I don't want to have to change my ep's or buy any more if I buy a faster scope.

[John]

Your eyepieces will work fine with a fast scope - you would be hard pressed to buy anything better to be honest.

The only thing you might find, if you have a long focal length eyepiece like a 40mm, is that, in an F/5 or faster scope, it produces an exit pupil diameter which is rather larger than you own dilated pupil so some of the light is wasted and you may see the shadow of the secondary mirror in some circumstances. But anything 32mm or less won't have that effect.

Pentax XW's, UWAN's and BGO's are very good eyepieces indeed

[vince 66]

So are these good scopes then? which should i go for the f4.5 or the f6 theres one of each for sale at the moment.

[John]

So are these good scopes then? which should i go for the f4.5 or the f6 theres one of each for sale at the moment.

I have an Orion Optics Europa 10" F/4.8 newtonian and that's got good optics - the SPX series are a step up again with better primary mirror cells and 1/8th wave optics / Hilux coatings as standard so, yes, they are good scopes. Personally I'd go for the 8" F/6 as it's a pretty good allrounder and will be a little easier to collimate and keep in collimation.

[vince 66]

Thanks I was thinking the f6 would be a bit better.