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Old 15-06-2009, 10:55 PM
Wavytone (Nick)
BigBanger

Wavytone is offline
 
Join Date: Jul 2008
Location: Killara, Sydney
Posts: 3,570
I have two sets...

Grab & Go set : 1.25" Vixen LV's - 4, 6, 7, 10, 15, 25mm.

Main set: "all 2-inch" - and similar in weight - so no fussing with rebalancing across this lot.

Vixen LVW 5, 8, 13, 22
Vixen NLVW 30
TMB 40mm Paragon, and
Vixen LV50

A full 10:1 range from highest to lowest power.

The 40mm Paragon takes in the full field of the 2" barrel - if your scope can fill it - which is why I bought it - but more below.

At the low end I started with the Vixen NLVW30 as I wasn't too sure whether either of my scopes could really fill the field of a 2" barrel. The field stop is 34.1mm, and gives a really gorgeous low power field in both my scopes.

Ultimately I decided to push the limits and try the TMB and the LV50. The TMB 40 is big. Looking at the field lens, it's aperture is bigger than some refractor objectives and you can't really appreciate how big till you hold one in the flesh. And as for the LV50... not many eyepieces have an eye lens cover BIGGER than the field lens cover - this one does as the eye lens is huge.

In my f/7 refractor the TMB 40 is good to the edge, a tad sharper than the LVW30 at the edges of the field and very crisp and contrasty. However it is not entirely comfortable to look through for long periods in comparison to the Vixen LV50 - which has a slightly smaller field field stop, a field of view of 45 degrees and heaps of eye relief.

My f/15 Mak however can't really fill the field of the TMB without some vignetting towards the edge of the field because the aperture at the back of the OTA is significantly less than 50mm. The same would be true for 8" SCT's.

Consequently while the TMB is spectacular in my refractor, I find the LV50mm is a better choice for low power on the Mak.
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Last edited by Wavytone; 15-06-2009 at 11:11 PM.
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