Quote:
Originally Posted by Startrek
Ryan,
Just like to share some of my personal guiding observations whilst imaging
I use the same mount ( EQ6-R ) and guide scope and guide camera at both Sydney ( Bortle 8 ) using a 6” f6 newt 900mm focal length and my weekender south coast NSW ( Bortle 3 ) using my 8” f5 newt 1000mm focal length and achieve “similar guiding error values” which are both dependent on seeing and transparency ( ie upper atmospheric conditions) and local conditions like wind , dew , humidity etc...
Excellent seeing 0.70 to 0.80 max arc sec error
Average to good seeing 0.80 to 1.00 max arc sec error
Poor seeing 1.00 to 1.30 max arc sec error
However after many imaging hours with both set ups I can honestly say that my Bortle 3 dark location has produced some of my best and most consistent guiding ( PHD2 ) after a 6 month comparison and using a heavier payload (the 8” f5 newt).Whether this is due to “lucky seeing conditions” down south compared to Sydney, I really don’t know or the EQ6-R performs better under a slightly heavier load or my polar alignment was slightly better , lots of variables !!!!
I balance both rigs “slightly east heavy” too
Also one observation I have experienced at both locations , under a +50% waning or waxing moon my guiding has been marginally worse than under a “No Moon” Bortle 8 and Bortle 3 sky.
Just thought I would share some of my guiding experiences over the past 6 months or so with a similar rig at 2 different locations
Cheers
Martin
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Thank you for your input Martin. I have a question for you regarding the variability of your observations based on mine. I find that the further away from SCP the object is, the worse my guiding is. This stands to reason as the sky effectively follows a much longer curved path and as such there is greater room for error. I wonder if you have also found the same?
My mount is heavily over weighted for imaging and although the 6 and the 5 are similar mounts, the payload is quite different. My total payload with the 200mm F/4 , guide setup and camera tops in at just over 11.5kg. Yes I do realize that that is half the problem. All that said, in my Bortle 8 suburban backyard with FWHM of rarely less than 4, I generally achieve average errors between .5 and .8 arc seconds. I am pretty happy with those numbers given what I’m dealing with but my practice with the newt guiding and subsequent tuning is more for my SCTs benifit. The filter was just one of the thoughts that went through my head and to be fair not the most expensive thing to try.
Thanks again for your input Martin
Cheers
Ryan