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Collimation aide for AA/GSO RC8 scopes


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I've drawn up a target sheet to aide collimating my Altair Astro CF RC8 OTA.
I place the scope/mount with weights vertially down and tube horizontal with a spirit level. I use a Glatter laser with standard holographic filter to align the focuser to secondary mirror then the circle/ring hologram to align the primary against the test sheet.
The test sheet for me is taped on the observatory wall aligning the cross against the vane shadows and the centre circle with the secondary shadow.
Miss-alignment can then be seen against the concentric circles on the test sheet.

Usually there is no need to further adjust on star testing but occasionally a small tweak is needed to centre secondary shadow in defocused stars.
This will print on an A4 sheet. Whole pattern if set at 100% and borderless, you loose the long edges if printed with borders.

Drop box link:


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