Adapter 2"/SCTi to T-2a, rotatable – for SC- and MAK-telescopes

Yes, the outer and inner part of the #2408160 adapter are identical to the #2958500B part. The only difference is that #2958500B comes with a 0,8mm T-2 fine-tuning ring to hold the parts together. This or a similar sized T-2 ring can be easily retro-fitted to the two #2408160 components. To achieve a T-2 optical length of 28,35mm you can use the Baader VariLock 29 (#2956929).

The total length of the adapter is 27,5mm minus 5mm T2 male thread is 22,5mm minus 7,5mm female SC 2" thread gives the optical length of 15mm.

Yes, you need the parts #16 (# 2408150) and #26 (#1508025) to mount the Alan Gee in a 2" eyepiece clamp, and in addtion some spacers to reach the desired distance between sensor and Alan Gee. For purchase in/delivery to the United States, please contact our distributor www.alpineastro.com.

Please note that the recommended distance between Alan Gee and the field stop of an eyepiece or a camera sensor is 121mm. It should not be much further away than ca. 130mm, otherwise the quality may suffer. The 2" SC/HD-Clicklock has got a length of 47mm, our 2"-mirrors ca 112mm, our 2" prisms about 100mm (both including their clicklock eyepiece clamps) and our 1.25"-T-2-prism 64mm incl. eyepiece clamp. So, it is okay if you use a 1.25" star diagonal, but with a 2" star diagonal, the Alan Gee will be too far away from the eyepiece. You can use the BTA (#21) and the Expanding Ring T-2f / M48m (T-2 part #29) #2458110 (optical length: 2.5mm) to attach the Clicklock to the BTA. But we'd recommend this only for 1.25" star diagonals. The ASI has got a backfocus of 12.5mm from the T-2-thread, so you need ca. 108.5mm of distance. If you attach the camera *directly to the BTA*, this can be achieved e.g. with - 2x 40mm T-2-extension tube (T-2 part #25B) #1508153 - VariLock 46, lockable T-2 ExtensionTube 29-46mm (T-2 part #25V) #2956946 This will give you a length of 109mm, or if you want the more precise, you can use - 1x 40mm tube - 2x 15mm tubes (#1508154) - 1x VariLock 46 to give you 99-116mm. If you mount the Alan Gee in *front of the Clicklock*, you need e.g.: - Expanding Ring T-2f / M48m (T-2 part #29) #2458110 - optical length: 2.5mm - 2" SC-Clicklock - 47mm - Baader 2" / T-2 Nose Piece (T-2 part #16) # 2408150 - optical length: 2.5mm - 2 x 15mm T-2-extension tube (T-2 part #25A) # 1508154 - 30mm - Baader VariLock 29, 20-29mm (T-2 part #25Y) # 2956929 - set to 26.5mm - ASI cam - 12.5 mm This will give you the desired working distance of 121mm.

Indeed - the T-2 section can be rotated into any desired position with the camera firmly on - and then the rotational position of the camera is locked by rotating the big 2" nut onto the 2" SC-thread. Inside the mechanism you can see three pressure plates in 120° spacing. This may have irritated you as it indeed looks similar to some dead lock solution. However - this is just to increase pressure when locking down the SC-nut, so that the T-2 thread cannot slip sideways once the 2"nut is tightened down. However it does not hinder free rotation of the T-2 thread at all during finding the optimum rotational position of the camera. We hope it answers your question satisfactorily.