SXV-AO-LF ‘Adaptive Optics’ Starlight Xpress

Overview

Major features:

• Image tracking and stabilisation using a high speed tip-tilt optical window.
• Fast tracking speed of 5mS per increment.
• Overcomes rapid gear errors to stabilise even difficult mounts.
• Mount control output for correcting large drive errors while maintaining AO stabilisation.
• Image shift factor independent of optical system or camera back-focus spacing
• Off-axis guider assembly (optional) for use with an SXV guide camera.
• STAR2000 guiding compatible.
• May be used to image stabilise many other makes and types of camera, given suitable control software.
• Clear aperture of 60mm for up to 35mm full-frame size chips.
• Short optical length – 74mm with OAG, 44mm without (add 6mm if front end adaptor is used).
• Very low light loss (~2%) from the multicoated optics.
• Filter threads for adding 48mm narrow band. IR blocking or pollution rejection filters without affecting the guide camera sensitivity.
• Serial RS232 control via the computer or SXV splitter box. Parallel control available.
• Low power consumption. Less than 600 mA at 12v DC when moving – 50mA quiescent current.
• Compact and lightweight – only 132mm in diameter x 32mm long – less than 700 grams load on the ‘scope.

Description

The SXV-AOLF should be used with the off-axis guider assembly for the best results with most optical systems. This combination uses an SXV guide head or Lodestar to view the edge of the telescope field via a 10mm square prism and provides accurate positional feedback to the control software. Unlike cameras with an integrated guider chip, the OAG puts the guide camera ahead of any filters that the user fits into the camera ring recess and so its sensitivity is always at maximum. The guide camera mounting is designed to be parfocal with an SX camera when used in this combination – fine focus adjustment is provided by moving the threaded guider mount along the prism tube. If you do not need the OAG barrel (e.g. when using a camera with a built-in OAG or guide chip), you can fit the 72mm or T adaptor directly onto the rear of the AO assembly.

The SXV-AOLF can also be used with our ‘Ultraslim’ OAG and filter wheel assembly. In this case, you do not need the OAG for the AO unit, just the T mount adaptor to connect the AO to the OAG, as seen above. You will save about 27mm of back focal length if you use this method.

STAR2000 cameras may be used directly without the OAG, but the AO correction rate must be kept reasonably slow, or amplifier glow effects may become a serious issue.

A front view, showing the imaging and guide camera CCDs, along with the input and output connections.

WARNING – this version of the update is applicable to ONLY older versions of the AO unit (pre-USB input). DO NOT load the update into a USB version or it will become unusable!! The warning in PHD2 should be ignored.

If you have the older serial port AO unit, download the serial port  SXV-AO utility & firmware version 120

If you have a new USB AO unit that needs programming, please use the AO utility with version 201 below:

Here is the current USB AO utility and firmware version – (issue 201)