Grab n Go with a 6" f6.5 Alt Az setup.
Re: Grab n Go with a 6" f6.5 Alt Az setup.
Hey btw, do let me know (PM?) of the Toa Payoh sidewalk sessions by Gary. I think that one is near to the main road, cab accessibility is good. Could be ok.
Re: Grab n Go with a 6" f6.5 Alt Az setup.
It is actually in a balanced position. I can move the dovetail around because it is the Losmandy Universal dovetail bar with lots of holes, and also can shift the tube postion on the scope around, but basically the Twilight II saddle to scope's tube position remains, hence the diag <-> tripod legs clearance is the same. ie COG same, just the bars and rings move.weixing wrote:Hi,
By the way, is the scope in balance position or this is a quick setup for photo taking? My 6" F5 is front heavy, so the mounting point is near the main lens.
Have a nice day.
But yes i can guess a 6" F5 would be much nearer to the main objective lens.
Re: Grab n Go with a 6" f6.5 Alt Az setup.
Robin? Hmm...frankly i can't comphrehend the rest of your paragraph... but, as long as this setup works and you are satisfied, then that's fine.vivid wrote: Robin’s suggestion of just slinging the weights through the central hole, that I have tried before. There is a small problem, because the weights central hole is not slippery so it does not slip until a certain angle, so through the scope the Alt becomes a bit sticky/resistance until the point it slips, and then it causes vibrations. With the cable tie it is constantly slipping, ie the shaft moves but...
...I can just run the AR152 without counterweights, but from my testing with weights it is far far smoother with correct balancing. In fact if I may hazard a guess, even a 80mm benefits from a nearly 100% balance in counterweights.
If the Twilight II needs counterweight to balance a 80mm and move smoothly, then it must be quite sensitive.
Richard Low
Re: Grab n Go with a 6" f6.5 Alt Az setup.
Haha....sorry I meant Richard. 
Well it's not that it's not smooth, i'd be ok to use the AR152 without counterweights.....last Thursday I tracked Saturn at 150X happily, no issue. I mean hey, with the diagonal this is a 1.2m long bugger and loaded with the ES82 30mm it is 13.5kg. C11 bare OTA is 12kg and the moment is definitely magnitudes lower than the long refractor....that's how i look at it.
Just that it can be optimised for better smoothness, more for the joy in usage. Properly balanced with nearly 1:1 weight distribution, it is absolutely effortless to position it, as if the weight is not there and just enough braking power. In fact with this weight system in place and by adding just some additional weights (assuming the M6 screw holding the shaft does not shear), i am very confident it can handle a 12" newtonian very smoothly. I have tried using both hands to press the saddle down with quite some force in addition to the weight from the scope and weights, it still can change Az and Alt very nicely. <<-- note, that'd probably kill my back first. LOL!
It's not easy to understand, actually i only recently found out that just by slipping those barbell weights onto the shaft it does not work. Before the purchase I also originally though that it could work.
I guess if it's a real quick look for easy /low power objects like the moon/M42, I can leave the weights out.
Well it's not that it's not smooth, i'd be ok to use the AR152 without counterweights.....last Thursday I tracked Saturn at 150X happily, no issue. I mean hey, with the diagonal this is a 1.2m long bugger and loaded with the ES82 30mm it is 13.5kg. C11 bare OTA is 12kg and the moment is definitely magnitudes lower than the long refractor....that's how i look at it. Just that it can be optimised for better smoothness, more for the joy in usage. Properly balanced with nearly 1:1 weight distribution, it is absolutely effortless to position it, as if the weight is not there and just enough braking power. In fact with this weight system in place and by adding just some additional weights (assuming the M6 screw holding the shaft does not shear), i am very confident it can handle a 12" newtonian very smoothly. I have tried using both hands to press the saddle down with quite some force in addition to the weight from the scope and weights, it still can change Az and Alt very nicely. <<-- note, that'd probably kill my back first. LOL!
It's not easy to understand, actually i only recently found out that just by slipping those barbell weights onto the shaft it does not work. Before the purchase I also originally though that it could work.
I guess if it's a real quick look for easy /low power objects like the moon/M42, I can leave the weights out.