When do I need the PrimaLuceLab M56 15mm Extension Tube?
You need this 15mm extension tube when your camera and accessories require a specific back focus distance that cannot be reached with your standard setup. It's commonly used to push the camera sensor further away from the focuser to accommodate reducers, flatteners, or off-axis guiders that have strict spacing requirements.
How does this 15mm extension connect to the ESATTO 2" focuser?
The extension tube threads directly onto the M56 male thread of the ESATTO 2" focuser's draw tube. The other side of the extension provides an M56 female thread, allowing you to connect your existing ESATTO 2" camera adapters or other M56-threaded accessories.
Can I stack multiple M56 15mm extension tubes?
Yes, you can thread multiple extensions together to create longer spacing (e.g., two tubes for 30mm). However, be mindful that each added connection increases the length of the imaging train, which can introduce flexure. For longer distances, a single, longer extension is generally preferred for maximum rigidity.
Is this M56 extension compatible with focusers other than the ESATTO 2"?
While it is designed specifically for the PrimaLuceLab ESATTO 2", it may be compatible with other focusers or accessories that use a standard M56 x 1mm thread. However, compatibility and correct spacing are only guaranteed within the PrimaLuceLab ecosystem.
Will the M56 15mm extension help me reach focus with an OAG on my Sky-Watcher Esprit 100?
Yes, this is a perfect use case. An off-axis guider (OAG) often consumes significant back focus. If adding your OAG and camera to the ESATTO 2" on your Esprit 100 leaves you short of the required spacing, this 15mm extension can provide the extra distance needed to bring both the main camera and guide camera to a sharp focus.
Why use this 15mm extension instead of just extending the ESATTO 2" draw tube?
Using a fixed extension keeps the focuser's draw tube more retracted. A more retracted draw tube is mechanically stiffer and less prone to tilt or sag, especially with a heavy imaging payload. This M56 15mm extension ensures your focuser operates in its most rigid range, improving the overall stability of your optical system.
