My Circle T collection

[philjay]

The collection is coming on.

 

The intention has been to build a set of period Circle T (Tani) volcano topped eyepieces which will be used with the 4" F15 and its starting to take shape now just got to get a proper wooden  box to put these in. 

 

I have now got 4,6,9,12.5,18 and 25mm circle Ts plus a couple of Circle T Kellners and a Circle V 25mm plus a Fullerscopes 25mm Ortho

 

The lens and brass tube on the left at the back is a period Fullerscopes adjustable barlow lens, you don't see these often and its also contemporary with the F15 I was well pleased to get that bit of kit rare as hens teeth.

 

The Celestron 40mm plossl at right is a temporary addition until I can bag the even rarer Circle T 40mm Orthoscopic. The 40mm is an ideal finder eyepiece with its lower mag.

 

As for performance of the circle T well Ive used a 25mm off and on for years and played with other folks' eyepieces but never had the opportunity till the other night to do side by side comparison to assess how good they are compared to modern eyepieces.

 

On lunar, Jupiter and Mars the other night through my 180 Mak I was astounded at how good these are. I did a comparison with my modern Vixen LVWs and I have to say apart from the 4mm which was a little soft compared to the LVW 3.5mm I could not see any appreciable difference in quality between the old Circle Ts and the LVW.

 

Yes the LVWs have 22mm eyerelief and 65 degree fov but quality wise I was most pleased. Also in all the eyepieces the true field was right across the viewing area which is far superior to a lot of modern eyepieces eg TMB planetaries where you have a sweet sharp spot in the middle 50% of fov then its softer. These are a pleasure to use on lunar. 

 

 

Edited April 10, 2014 by philjay

[Doc]

I still have the 4,6,9,12.5, and 25mm Circle T's as well Phil, I used to use them with the Tal refractor.

 

They are pretty sharp eyepieces, my favourite was the 12.5 mm.

 

Most of my Lunar 100 was done using them.

 

Great collection Phil.

 

 

Edit:

 

Mine are Telescope House is the same thing.

Edited April 10, 2014 by Doc

[philjay]

I know what you mean about the 12.5, the 18mm is a cracker as well.

[+Ibbo]

I still have an 18mm and the erfle 40mm is somewhere around

 

was nicknamed the awful as we believe it had been opened p and not put back right

[philjay]

 I had a 20mm Erfle which I christened awful as well

[Guest Nightfisher]

classic eyepieces, i have the full set, other than my 18mm is the BGO not a VT

[philjay]

As a footnote, I used the Fullerscopes variable barlow last week on Mars and what a useful bit of kit it is. It just fits in the draw tube and the magnification depends on how far down the tube it goes, this has greatly extended the range of the set.

Edited May 5, 2014 by philjay

[philjay]

Update

 

I managed to find an appropriate box for them, an old 60s/70s oak microscope box from auction.

I knocked out the interior and replaced the hardboard base with ply.

Fitted a foam interior from a spare maplins case.

Fitted the internal rim with a lip to help centre lid.

A bit of beeswax polish to the outside eh voila!

 

 

I now have a box which looks more the part than a Maplins case when I use these with my 4" F15.