skywatcher guider

[rightguard]

having some trouble with the stand alone skywatcher guider.

It is pretty light polluted round here in reading but I wouldve thought it should find something in my 200p?

exposure at 4056, and nothing.

Is it a fault with the kit or is it just not worth its weight?

Anyone had one, or got any thoughts? Brought from FLO on 25th Oct, might be able to get refund?

[Stephen]

Are you using it in an OAG?

[rightguard]

no, first tried it in a homemade finderscope, but then decided that since im new to this i should insert it into the 200 focuser and piggy back the dslr till i know what im doing

[Stephen]

Well in an ST80 (so I assume a finder scope as well) you need a huge extension tube to allow it to focus (like 80mm or so.)

I've never tried it in a 200P, can't say I ever heard of anyone doing it that way either

Never the less, I have to wonder if you have enough in / out focus. (You have gone the full extent of the focuser each way with a 4s pause at each step?)

Verify you are pointing at a bright star (use a 10mm EP) and then swap the synguider in.

If you can't see anything on the screen, try drawing it slowly out of the focus tube and see if anything appears on the screen.

[rightguard]

i tried it on jupiter last week and it found it. didnt focus to a fine point but i assumed that was it wasnt a point liek a star would be.

tried on a bright star this evening. centred and focussed with a 5mm ep. kept focus similar and put in the guider. nothing.

kinda put me off the whole thing.

[Stephen]

i tried it on jupiter last week and it found it. didnt focus to a fine point but i assumed that was it wasnt a point liek a star would be.

tried on a bright star this evening. centred and focussed with a 5mm ep. kept focus similar and put in the guider. nothing.

kinda put me off the whole thing.

I'd send it back to be honest if you aren't happy - at FLOs discretion of course.

[rightguard]

just emailed them explaining and asking for a refund.

only brought it 2 weeks ago and ive heard good things about flo so finegrs crossed.

[AndyUK]

The Synguider does work, and works very well (IMHO), but you do need to be able to bring it to focus. I was never able to get it to focus with a finderscope (helical focuser), but on the end of a piggybacked ST102 (or as mentioned above, an ST80) it's comparatively easy (honest!).

I used to use mine with a diagonal (probably frowned upon), but pointing it at a bright named star (Vega, Caph, Capella, Altair etc) I found that to get a BRI level of about 20, the exposure was around 32ms or even 16ms (which is actually way too low for guiding, but useful for getting reasonable focus). However, with a star that "big", it does look like a "blob" on the screen, but the trick is to play with the focuser until you have the greatest BRI value for the exposure setting you've selected - Once you've achieved that, you can then move to your chosen target and either adjust the guiderings to centre your chosen guide star (if you have a guidescope) and use auto select or you can manually select a star on the screen.

Synguiders seem to be something people either love or hate - I loved mine, but as I was getting differential flexure from the piggybacked ST102 (and wasn't able to focus the synguider through a finderscope), I eventually moved over to a lodestar and PHD... I actually seem to have more guiding issues now, but when I get the settings right, the flexure has totally disappeared and is superb... but I still believe that if I'd been able to find a way of focusing the Synguider through a finderscope that would have been my personal ideal solution.

As you don't have an ST80/ST102 type guidescope and are simply trying to test the synguider through your 200P, I'd agree with Kh3ldar - Try getting a 10mm EP centred on a bright star and then insert the synguider (without an extension tube) and slowly pull the focuser in/out... and if you still can't get focus, put an extension tube in (or a lensless barlow?) and try the process again. I would have thought that you really should be able to achieve focus on a fairly bright/named star... But for an ongoing guiding solution with the synguider, I would suggest you consider either a side-by-side or piggybacked solution (although if you can succeed where I failed by getting it to focus through your finderscope then I think you're onto a winner!)

[rightguard]

stuck between a rock and a hard place.

will try moving in and out next time im out with it.

this is definately a preferred method of guiding as it doesnt require a laptop, 1 less thing to carryout! but if its not going to be any good then itl have to go. shame.

[AndyUK]

I feel your pain - I didn't want the grief of a laptop either... but the noise that crept in to the DSLR images got to me last April and I took the leap to mono CCD imaging / setpoint cooling (so the laptop arrived anyway). However, I still have the modded DSLR and when it starts getting colder again, I'm sure it will come out again. I've accumulated too many mono images since getting the CCD and the weather this year has hardly been conducive to mono "colour" imaging... and my wife is getting bored of mono Ha images! But PHD also seems to be an art unto itself - Focusing / star selection is MUCH easier (bigger screen), but I'm really struggling to get the settings right

[AndyUK]

I had another thought - You also need to check your "noise" setting - If it's too high, you won't see anything. I remember the first time out I tried to use it, I discovered that, for some reason, it was initially set at about 50!

If you reduce the noise value as far as you can (towards 1) the screen will eventually go all red. If you then increase the noise value step by step until the screen isn't all red, it will then be at it's most sensitive point. For reference, I used to find a value of about 6 or 7 about the norm when in use so I'd suggest you start with a setting around that mark to begin with.

When you do get some stars on the screen, increasing / decreasing the noise value will increase/decrease the number of stars you see, but of course for this testing phase (using a FL of 1000mm), you're going to need to ensure that you're framing on the bright star is reasonably good. When using it "for real" though (in your case through your finderscope) you should have quite a selection of guidestars available and it's then that you'll need to choose one that gives you a BRI value of around 15-20 with an exposure of 1024-2048s. Although the Synguider screen isn't great, its sensor is pretty sensitive and on a good night you should be able to guide on a star about mag 7 ish with no real problems. Flexure aside, when using the DSLR, getting 10 min exposures was no problem at all...

I wrote the attached for another SGL member - It was specific to his rig, but maybe it might help?

Synguider Process Doc.doc

[rightguard]

thanks very much andy, much appreciated

[x6gas]

I have a SynGuider as well and I am in the 'love' camp.

There is a process in the manual that describes how to make a parfocal eyepiece (i.e. an eyepiece with the same focus point as the synguider). That for me is an absolute must do. It means that you can see what's going on before swapping the synguider in and makes life much easier. The synguider comes with a ring that you use on the eyepiece to achieve this and I use a cheap plossl that came with a scope.

You do need a bit of apperture for it to work properly. I started with a 70mm frac and it struggled (now have an ED80 with no problems) so i don't think you'd get away with it on a finderguider unless you're up at that kind of apperture...

Give it another chance!

[rightguard]

ahh. sent off to flo yesterday and have been refunded. will try guiding in the new year.