Astro T-2 System Specs
| Part # | Description |
Optical Path Length (mm) |
Threads/Size,
Objective End |
Threads/Size, Eyepiece End |
Filter/ Auxiliary Threads |
| MAX-1 | T-2 Maxbright Mirror Diagonal | 54 | T-2 (i) | T-2 (e) | - |
| AMICI | Deluxe Amici Diagonal | 49 * | T-2 (i) | T-2 (e) | - |
| T2-01B | T-2 Prism Star Diagonal | 42 * | T-2 (i) | T-2 (e) | - |
| T2-01C | T-2 Prism Star Diagonal | 38.5 * | T-2 (i) | T-2 (e) | |
| T2-03 | Adapter 36.4/T-2 (Takahashi/Vixen Small) | 0.5 | M36.4 x 1 (e) | T-2 (e) | M34 (i) |
| T2-06 | T-2 Quick Changer | 11 | T-2 (i) | Bayonette (i) | - |
| T2-07 | T-2 Change Ring | 4 | Dovetail (e) | T-2 (e) | Ø38mm(i) |
| T2-08 | Clicklock Eyepiece Clamp 1.25"/T-2 | 32-38 ** | T-2 (i) | Ø1.25" (i) | T-2 (e) |
| T2-09 | Zeiss M44/T-2 Adapter (Inner) | 14 | T-2 (i) | M44 x 1 (i) | - |
| T2-10 | Reducer 1.25"/.965" | 6.5 | Ø1.25" (e) | Ø0.965" (i) | M28.5 (i) |
| T2-12 | Takahashi Converter M43/T2 (fits Takahashi Focusers) | 1 | M43 x 0.75 (e) | T-2 (e) | - |
| T2-12b | Zeiss Position Circle | 18 | M44 x 1 (e) | M44 x 1 (i) | - |
| T2-13 | Zeiss Camera Adapter M44/T2 | 5 | M44 x 1 (e) | T-2 (e) | Ø38mm(i) |
| T2-14 | Nosepiece 1.25"/T2 | 0.5 | Ø1.25" (e) | T-2 (e) |
M28.5(i)/ M34 (i) |
| T2-15 | Deluxe Reducer 2"/1.25" | 14 | Ø2" (e) | Ø1.25" (i) | M48 (i) |
| T2-16 | Nosepiece 2"/T2 | 2 | Ø2" (e) | T-2 (e) |
M48(i)/ T-2 (i) |
| T2-17 | 2" Deluxe Clamping Eyepiece Holder | 53 | UNC 2" (i) | Ø2" (i) | - |
| T2-21 | Short T-Adapter (16mm) | 16 | SCT 2" thd (i) | T-2 (e) | Ø38mm(i) |
| T2-22 | Adapter M43/T2 (Vixen) | 2.5 | M43 x 1 (e) | T-2 (e) | Ø38mm(i) |
| T2-23 | Russian Camera Adapter M42/T2 | 7 | M42 x 1 (i) | T-2 (e) | Ø38mm(i) |
| T2-25A | T-2 Extension Tube 15mm | 15 | T-2 (i) | T-2 (e) | Ø38mm(i) |
| T2-25B | T-2 Extension Tube 40mm | 40 | T-2 (i) | T-2 (e) | Ø38mm(i) |
| T2-25C | T-2 Extension Tube 7.5mm | 7.5 | T-2 (i) | T-2 (e) | Ø38mm(i) |
| T2-26 | Inverter T-2/T-2 | 0.0 | T-2 (e) | T-2 (e) | Ø38mm(i) |
| T2-27 | Adapter 2"/T-2 | 0.5 ** | SCT UNC 2" (e) | T-2 (e) | M48 (i) |
| T2-28a | Expanding Ring T-2/2" | 1 | T-2 (I) | UNC 2" (e) | - |
| T2-29 | Expanding Ring T-2/M48 | 2.5 | T-2 (i) | M48 (e) | - |
| T2-30 | Focusing Ring Collar FR-4 | 9.9 | 1.25" (i) | - | - |
| T2-32 | 2" Deluxe Clamp | 17 | |||
| T2-34 | T-2 Conversion Ring | 10 | T-2 (i) | T-2 (e) | - |
| T2-35 | T-2 Locking Ring | 2 | T-2 (e) | T-2 (e) | - |
Notes:
(i) = Internal Thread
(e) = External Thread
T-2 Thread = M42 x 0.75
* Typical Value, measured at f/5.5. Effective Path Length will be slightly different due to optical effect of prism on path length (less path length is required for scopes faster than f/5.5, more for longer scopes).
** When using the T2-08 plus T2-27 with the Herschel Wedge, the range of clearance from top of the T2-08 to the filter glass surface is 38-44mm.