Lacerta 1:10 Microfocus Unit - Dual-Speed Crayford Focuser Upgrade.
This is a high quality but economical solution to upgrade your Single Speed Skywatcher Crayford Focuser.
Compatible with all Dobson and Newton (from 20cm diameter of the main mirror size) and ED-APO single speed Skywatcher Crayford focusers. However if you are not sure, please contact us to check out compatibility.
Many of the larger models of SkyWatcher telescopes, such as the ED APO PRO Series, Dobsonians and Newtonians (from 20 cm diameter) have (thanks to a longer distance between the two ball bearings) a very stable Crayford, but without micro-focus unit. Lacerta have designed a universal Microfocuser, which should fit all previously manufactured SkyWatcher Crayford focusers (ie.focusers without dual-speed micro focuser).
Please note, images are for demostration purposes only. We should mention that the logo at the end of the smaller know has changed to a lizard, which represents the constellation Lacerta (i.e. Lizard), that is also the brand name of this manufacturer...
FAQ - Frequently Asked Questions
- What is so special about this Microfocuser?
The micro-focus unit is different from previous upgrade versions. The way earlier versions were designed resulted in uneven course of focusing. We now replace the whole plate of the Crayford-back to a new, which can be adjusted several times: the pressure plate can be tilted and even the axis of the micro-focus unit can be adjusted with the help of four adjustment screws. This results in even travel of the focuser unit.
- Why do we need various adjustments for the micro-focus unit?
Earlier versions had only two adjustment screws: one for the brake and the other to increase the pressure on the Crayford-axis and thus on the extension tube. If the distance is not set correctly, this pressure can cause a slight bending of the Crayford-axis. Because of this bend rubbing the end of the Crayford-axis and thus runs the focuser not evenly.
But if the distance between the Crayford-axis and extension tube can be adjusted sensitively, no bending will occur on the Crayford-axis anymore, even if we increase the pressure on the Crayford-axis and this will result in a dual-speed focuser with fine, stable and precise movement.
- How to adjust the micro-focus unit?
Loosen both adjusting screws and whilst rotating thefocuser/microfocuser, slowly tighten the adjustment screws.
A detailed Replacement and Adjustment Instructions with photos of each step will be available soon.
- Can the focuser be upgraded with motorized focus?
Thanks to the complete replacement of the holder plate (Crayford-back), the popular motor focus can still be mounted, as the Lacerta 1:10 microfocus unit add no extra thickness like other versions do.
- What-axial stability is to be expected from your Crayford after upgrade?
A well-adjusted Crayford should hold about 3kg weight in the axial direction without losing focus without additional screw.