Can my guiding be improved (cheaply/free!)

[Skipper Billy]

1 hour ago, blinky said:

I wonder if it’s time to sell the Lodestar..... if I need to use bin2 to get round interlacing, realistically it having a guide camera with 16um pixels guiding a camera with 3um pixels going to work? Might be better to sell and buy the ZWO guider instead.

I used my Lodestar 1x1 and 2x2 and to be honest I didnt see much difference in guiding performance (both were very good).

I bought a ZWO290 mono with the idea of making an 'all sky camera' but havent done it yet. I tried the 290 as a guide camera and it is much better than the Lodestar - smaller pixels, more sensitive and my guiding with it (with a SW ED72) is very, very good.  

The Lodestar used to be the 'gold standard' of guide cameras but maybe it is losing it's crown??

[blinky]

Interesting, don’t think I can stretch to the 290, was thinking of the 120 for guiding

[Skipper Billy]

42 minutes ago, blinky said:

Interesting, don’t think I can stretch to the 290, was thinking of the 120 for guiding

Cant speak about the 120 from personal experience but a lot of people use it VERY succesfully.

[blinky]

I’m gonna persevere with the Lodestar for the moment I think - get properly polar aligned and also push the prism a bit further in to see if the star shapes get any better.  In theory at 1x bin the Lodestar is a little less than half the ASI1600 pixel size so I would think it would be able to guide it OK through an OAG

[ollypenrice]

I'd be inclined to guide more frequently, at least to see if it worked. I haven't used our EQ sixes myself recently, I just have them to lend to guests, but I think I used to go as low as 0.5 seconds.

As Ole says, your RMS needs to about half your pixel scale.

Regarding the flex in OAGs, I made a strap to hold this one solid. It worked fine.

I must admit that I use our Lodestars in Bin 1, having been entirely unaware that this was supposed to be an issue. I'm using one in a 400mm guidescope to image at 0.9"PP. In the setup above we were also using Bin1 at just over 0.6"PP.

Olly

[blinky]

Thanks Ollie - Seems that although it says to Bin 2 a few folks have been using Bin 1 completely unaware of this and have no issues.  As I live in Scotland and dont have the benefit of your skies it may well be weeks before I can mess about with this avian!

[Xplode]

For OAG guiding the ASI 120 isn't a good choice, you're better of sticking to your Lodestar.
The theory is that you can guide at almost 1/10 the resolution of your imaging scope, you're at around 1/4 so that should be no problem.

If you wanted an uprade to the Lodestar the ASI290 or the ASI174 is the best choice, in my opinion ASI290 with a small guidescope and ASI174 for longer FL guidescopes or OAG.
Lodestar is indeed not the best guidecam and haven't been for years, imho it's way overrated, but still sell well because of it's good reputation
 

Here's a screenshot at 1855mm/f5 with an ASI174 at 0.65", main camera is at 0.67"
The best i have seen is RMS 0.31"
I'm sure this can be improved upon with some small improvements that i don't think is up to my standards
I have also seen flex in the OAG, USB cable from the guidecam is now strapped to the main camera so it doesn't create unnecessary weight on the OAG.

[Anthonyexmouth]

+1 for the 290. I was using an older 120m which was ok but when it started playing up I couldnt afford a new one so i demoted my 290c from planetary imaging, which it did very little, to being a guide cam. Very happy with it, if i could afford a mono one i imagine it would be even better. using it with an ST80

[blinky]

Think I finally got it all sorted...… Nice round stars at 5min exposures, same setup, imaging at 0.98arcsec/pixel.  I rebalanced, re-polar aligned and redid the guiding assistant