Step-Down Adapter from 3.27" to 68mm for CMOS and CCD Cameras (ADA327-68)

In July 2024, we added several adapters to simplify your CMOS or CCD imaging train when used with the field flatteners and telecompressor correctors (TCC) developed for the 3.5" or 4" focuser. These adapters were designed to retain the largest diameter possible just before the camera or filter wheel. This will provide strength, reduce flexure and reduce vignetting.

Applications

CMOS camera systems that provide a distance of 55mm from the camera sensor to the back of the adapters and/or OAG and filter wheel : When using ZWO, QHY and other similar cameras, these adapters will achieve the desired 80.8mm spacing from the camera sensor to the back-focus spacer of the field flattener or TCC. Refer to the CMOS camera system diagrams below.

CCD and other CMOS cameras: These adapters allow you to connect with the 48, 54 or 68mm threads of your camera. You may need a custom spacer (3.27 x 16tpi Male / 3.27 x 16tpi Femaie) to span the distance from this adapter to the back flange of the field flattener or TCC. There are so many camera models available that we can't provide spacers for all possibilities. Refer to the CMOS camera system diagrams and other diagrams related to your system below.

Designed for these Field Flatteners and TCCs with their recommended Back-Focus Spacers and/or SRSET-327 Spacer Rings: 

All of these utilize our Astro-Physics 3.5" focuser or 4" focuser.

• 110TCC and 110FF 
• 13035FF-2, 13035FF-3, 13035TCC-3 and 13035TCC-2
• QUADTCC-155 and QUADTCC (all versions)
• 14035FF and 180F7FF
• Legacy field Flatteners: 160FF, 175FF 
• Legacy Telecompressor Correctors: 155TCC, 160TCC, 175TCC

Select Adapter

Select the appropriate adapter to step down to the threads of your CMOS or CCD camera system.  

ADA327-48, step down to 48mm threads
ADA327-54, step down to 54mm threads
ADA327-68, step down to 68mm threads

Specifications

• Net spacing distance: 25.8mm.
• A mono camera with filters requires an extra 1mm added to the adapter length to compensate for filter thickness. We suggest that a spacer ring from the SRSET-327 be used.
• CMOS thread: 48mm
• Female threads: 3.27 x 16tp, to use with the back-focus spacer specified for your field flattener or TCC. 

Diagrams and Instructions

Refer to the following diagrams for additional information regarding spacing.

Current recommendations:

• 110GTX CMOS Camera System Diagram
• 130GTX CMOS Camera System Diagram
  
  
• 175 & 160 CCD Field Flattener Spacing Requirements, includes legacy adapters, consider ADANIK-Z instead
• 0.76x 155TCC, 160TCC & 175TCC Telecompressor Corrector Spacing Requirements, includes legacy adapters, consider ADANIK-Z instead
• 0.72x QUADTCC (all versions) Telecompressor Corrector Spacing Requirements, includes legacy adapters, consider ADANIK-Z instead

Legacy documents for your reference in case you own some of these components:

• Field Flatteners, TCCs & QUADTCC Imaging Train Options

• 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. 

Custom Spacers & Adapters

If you need a spacer or adapter for a configuration that is not described above, we recommend that you contact PreciseParts. You may also review the following diagram that shows additional components you might find useful. Keep in mind that some are legacy parts: Field Flatteners, TCCs & QUADTCC Imaging Train Options

Astro-Physics 80.8mm Back-focus Spacing Distance

For more information regarding the concept for the 80.8mm back-focus spacing distance, refer to this webpage: Spacers & Extensions