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Shelyak C-mount to T-mount adapter ring

Shelyak C-mount to T-mount adapter ring

by Shelyak
SKU SHK-BA0034
CA$78.00 - CA$78.00
CA$78.00
CA$78.00 - CA$78.00
CA$78.00
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  • Connects female C-mount threads (25.4mm) to male T-mount threads (M42x0.75mm)
  • Enables use of larger T-mount cameras on C-mount guide ports or accessories
  • All-metal construction for secure, flex-free connections
  • Low profile design minimizes added back focus
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  • Description
  • FAQ
  • Specifications
  • In the Box
  • Warranty

  • C-mount to T-mount adapter ring

    This C-mount to T-mount adapter ring physically connects two essential standards in astronomical and industrial imaging. It features a male M42x0.75mm T-thread on one side and a female internal 25.4mm C-mount thread on the other, providing a simple, rigid solution for integrating hardware that would otherwise be incompatible.

    Connecting T-Mount Cameras to 25.4mm C-Mount Ports

    The primary function of this adapter is to mount a camera with T-threads—such as a DSLR or a large-sensor astronomy camera—onto a device with a female C-mount port. This is a common requirement when using an off-axis guider's guide port, a microscope eyepiece port, or other specialized optical equipment that defaults to the smaller C-mount standard. This converter allows you to use your preferred, often larger, guide camera where only a C-mount was previously possible. Note that depending on your camera's sensor position, an additional C/CS-mount spacer ring may be required to achieve the correct back focus.

  • What is the primary use for this C-mount to T-mount adapter ring?

    Its main purpose is to allow a camera or accessory with male T-threads (M42x0.75mm) to be attached to a device with a female C-mount thread (25.4mm). This is most often used to connect a larger format guide camera to a smaller C-mount guide port on an off-axis guider or finderscope.

    What are the exact thread specifications for this adapter ring?

    The adapter has two distinct threads:

    • Male Thread: M42x0.75mm, commonly known as T-mount or T2-mount.
    • Female Thread: 25.4mm (1-inch) diameter with 32 threads per inch, which is the C-mount standard.

    Can I use this adapter to attach my DSLR camera to a microscope C-mount port?

    Yes, this is a valid application. If your DSLR has a standard T-ring attached (which provides male M42x0.75mm threads), this adapter will allow you to screw it directly onto a C-mount photo port on a microscope, assuming you can achieve focus.

    Will I need additional spacers for my guide camera to reach focus with this adapter ring?

    Possibly. The C-mount standard has a flange-to-sensor distance of 17.526mm, while the related CS-mount is 12.5mm. If your guide camera is CS-mount native, you will likely need a 5mm C/CS spacer ring in the optical train to reach focus. This adapter does not change that fundamental spacing requirement.

    Is this adapter the same as a T-ring for a camera?

    No. A T-ring adapts a specific camera brand's lens mount (like Canon EF or Nikon F) to a male T-thread. This adapter takes an existing male T-thread and converts it to fit into a female C-mount port. You would typically use a T-ring on your camera first, and then attach this adapter to the T-ring.

    Does this C-mount to T-mount adapter add significant length to the optical path?

    No, this type of adapter is designed to be as thin as possible to minimize its impact on back focus. While it adds a few millimeters, it is generally considered a "low profile" adapter and should not prevent you from reaching focus in most setups that have sufficient travel.

  • Male Thread M42x0.75mm (T-mount)
    Female Thread 25.4mm x 32 TPI (C-mount)
    Function Adapts T-mount (male) to C-mount (female)

    • C-mount to T-mount adapter ring

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  • Shelyak 1-Year Warranty