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Testing Changes last night
Last night Sydney had a rare clear night ( 90% waning moon ) so took the opportunity to test a few changes to my rig
New USB3 Hub
To minimise cable drag , I eliminated 2 cables going from laptop to mount / scope by fitting a new USB3 hub to the underside of the Losmandy dovetail plate. Bought a Startech Industrial USB3 4 port powered hub and connected imaging camera , guide camera and mount via Startech USB3 and USB2 1m cables.I use a 5m Startech Active USB3 main cable from Hub to laptop.
Worked perfectly all night with all software programs , APT , Stellarium, EQMOD, PHD2. With USB3 set ups you have to find quality cables that are USB3 performance certified ( there’s so much junk out there claiming USB3 conformance ) and keep your distribution cables from hub to equipment on the mount no longer than 1m (the Startech USB3 cables have not let me down, so far after 3 years )
Re Orientation of OTA and rebalance
Down south at my Obs , I reorientated my 8” Newt with camera facing down at 6 o’clock in lieu of at 2pm, re balanced it and this proved to have a significant improvement in tracking and guiding.
I did the same re orientation last night on my 6” newt and again the guiding numbers were a marked improvement from previous
Previous 0.70 to 0.80 arc sec error ( over 3 years )
Last night 0.52 to 0.60 arc sec error ( in 4 different locations in the sky ) I’ve had this mount ( EQ6-R pro ) over 3 years and never had the guiding so tight. Ra and Dec were well behaved using the PPEC algorithm in PHD2 ( with dithering) and only noticed one or two small excursions all night.
Tilt evident in image
After reviewing some 5 minute subs , I did notice some evidence of tilt in the smaller fainter stars across the image, nothing too alarming but it’s there . I’m confident it’s due to the re orientation of the OTA with camera facing down as now the camera is exhibiting more torque on the focuser than ever before in most positions.The 2600MC with adapters and Baader MPCC is a lot of weight hanging out from that little 6” newt. May need to use some ring spacers and tighten up the whole assembly a bit better ( a works in progress)
Heavy dew set in around 1am , it was a productive night and tested and proved a few changes which went well
Cheers
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