Pegasus M68 Male to M42 Male Adapter
- Connects M68x1 accessories to M42x0.75 T-threads
- Adds only 4mm of optical length to the imaging train
- Male-to-male thread configuration for direct coupling
- Standard M42 pitch of 0.75mm ensures wide compatibility
This Adapter M68 Male to M42 Male provides a robust, direct connection between large-format M68 accessories and standard M42 T-threaded components, adding only 4mm of length to your optical path. The standard M42 thread pitch of 0.75mm ensures compatibility with a wide range of cameras, filter wheels, and off-axis guiders.
Engineered to solve a common connection challenge, this adapter allows you to step down from the larger M68 thread standard—often found on high-end focusers, field flatteners, and rotators—to the universal M42 T-thread. Its key feature is the minimal 4mm optical length, which is critical for maintaining correct back focus distances, especially in systems with reducers or correctors that have tight tolerances. The male-to-male design creates a solid, secure link between two female-threaded components, eliminating flexure in the imaging train.
This adapter is designed to connect a component with a female M68 thread (like a large focuser drawtube or a full-frame corrector) directly to a component with a female M42 T-thread (such as a DSLR T-ring, a filter wheel, or an astronomy camera).
The adapter adds exactly 4mm to your back focus distance. You must account for this when calculating the spacing for your flattener or reducer. Its minimal profile is designed to consume as little of your precious back focus as possible.
Yes. The M42 thread has a pitch of 0.75mm, which is the universal standard for photographic T-threads used in astronomy. This ensures compatibility with the vast majority of T-rings and camera adapters.
This depends on the specific threads of your components. If your Esprit reducer terminates in a female M68 thread and your ZWO camera or filter wheel has a female M42 T-thread, this adapter will bridge the connection, assuming the 4mm path length fits within your back focus requirements.
A male-to-male adapter acts as a thread changer and coupler between two components that both have female threads. It's a common requirement when connecting parts from different manufacturers that were not originally designed to mate directly.
Stepping down from a large M68 opening to a smaller M42 throat can introduce vignetting, especially on fast optical systems or with full-frame sensors. While the adapter itself is low-profile, the M42 standard is the limiting factor and is generally better suited for APS-C or smaller sensors to avoid dark corners in your images.
| Connection 1 | M68 Male Thread (M68x1) |
| Connection 2 | M42 Male Thread (T-2) |
| M42 Thread Pitch | 0.75mm |
| Optical Length | 4mm |
Adapter M68 Male to M42 Male
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