Step-Down Adapter with 2.7" Male Threads to 42mm Male Threads (ADA27-42)
Brand : Astro-Physics
We have designed a series of adapters to assist imagers obtain back spacing distances for their camera systems. It is important to retain the largest diameter possible to the imaging train until just before the camera or filter wheel. This will provide strength, reduce flexure and reduce vignetting. These are some of the components that you may wish to consider. Be sure to refer to the Imaging Train Option diagram below to see how each one can be used and additional components that will be needed.
The following adapters can be used to step down from the 2.7” thread of the appropriate extension to the threads of your camera or filter wheel:
ADA27-42, step down to 42 mm threads, net spacing distance: 0.2” (5.1 mm)
ADA27-48, step down to 48 mm threads, net spacing distance: 0.2” (5.1 mm)
ADA27-54, step down to 54mm threads net spacing distance: 0.2” (5.1 mm)
ADA27-68, step down to 68 mm threads, net spacing distance: 0.2" (5.1 mm)
ADA27-2156, step down to 2.156” threads, net spacing distance: 0.2” (5.1 mm)
ADA204, step down to 2” SCT threads, net spacing distance: 0.3” (7.3 mm)
Our 2.7” Extensions (EXT27-) and Spacer Rings can be combined with the above adapters to help you meet optical spacing distance requirements. Each has a different net spacing distance. In May 2021, we changed our part # system so that you can determine what you need more easily.
EXT27-15.2, (former part # A3505), net spacing distance: 15.2mm
EXT27-19.1, (former part # A3503-A), net spacing distance: 19.1mm
EXT27-22.9, (former part # A3506), net spacing distance: 22.9mm
EXT27-27.0, new in 2021, net spacing distance: 27.0mm
EXT27-31.8, (former part # A3504-A), net spacing distance: 31.8mm
EXT27-44.5, (former part # A3502-A), net spacing distance: 44.5mm
EXT27-64.8, (former part # A1008-A), net spacing distance: 64.8mm
SRSET-27, set of three 1mm thick spacer rings.
It may still be necessary to use a custom adapter to complete the connection, but using combinations of the above adapters will greatly reduce cost by eliminating the need for multiple and costly custom adapters.
Diagram and Instructions
If you own items not shown in the diagrams above, please refer to the Discontinued Products section of this website and Technical Support for Legacy Products that are No Longer Available.