Skyliner 250px synscan query

[skywatcher250]

Ok so I'm not sure if i got very lucky today or something but my star test looked pretty good... The collimation didn't go well and the scope still needs doing badly, I can't even see the primary mirror clips....anyway I went out tonight and slewed to a few stars.... Here is my question

I tried to 2 star align and brightest star in both cases the 2nd star was well off... I checked it was level (wasn't too bad), checked date and time and daylight savings and inputted coords as my iPhone told me but I must be doing it wrong

Is there a way of getting exact coords and what else could I be doing wrong pls

Stunning night out there!!!!

[skywatcher250]

i can't seem to edit the above post so apologies for writing underneath - i think my problem may have been i used my iPhone to find my coords via the compass - it occurred to me today that the phone although it SHOULD be correct, its always on the move and may well be wrong - after checking google maps its seems the longitude was a fair bit off... I'm wondering if that was the problem

[Paulb3098]

Hi, I normally use the 2 star alignment, I tend to find Synscan selects the second star behind a tree or a neighbour’s house. Make sure you also use a high mag EP, this gives better accuracy when using the goto during your session. The second star is never spot on, the less accurate you are on the first star alignment the more chance it will be out of the FOV. To align the second star use the arrow keys and nudge until its central (same as the 1st star), once again worth using a low EP to start with and tweaking with a high EP. On the collimation issue, worth getting a HoTech SCA laser or a good chesire. Good luck Paul

[skywatcher250]

thanks paul - may i ask - the 2nd star was literally about 20 degrees out - quite a lot - do you think it was down entirely to my iPhone giving me a false reading of gps - when i try with google maps gps this eve it should work right ?

thanks

[squeaky]

20° out?!?

I usually find that at most the second star is off by a single degree, so yes, you've clearly got one of your inputs wrong. If you put your location plus latitude into google (as in "Sin City latitude" - without the quotes) or even your post-code, you should come up with plenty of results.

I've also found that using Polaris as the first star seems to result in better tracking further down the line. I have no idea why... unless you're supposed to start the two star alignment with the scope ALREADY pointing to the Celestial North Pole and THEN pick two stars to align from? The book's not very clear on this.

[skywatcher250]

im guessing my iPhone let me down squeaky - will certainly try again this eve using googles coords

i believe that as per the manual i have to have it a 0 degrees (basically horizontally flat) facing as close to north as i can (iPhone compass) and then turn it on... then i have to start the align and push the scope by hand to polaris, centre it click enter than it should find the second one auto ?does that sound about right - i hope i understand it now for tonight !

[squeaky]

Yep, sounds right enough - given that you have the right coordinates in

What I do is centre the target star in my lowest magnification eye piece, then step up to the next EP and centre, and then again with the next EP... go as high as I can. That way it's as accurate as I can get it. Then start again from the lowest mag EP when on the second star.

To get a GOOD Celestial North Pole (NOT magnetic from a compass because magnetic North is about seven degrees away from Celestial North) use a program such as Stellarium so that you can star hop from Polaris to a "best guess" on the actual CNP. I say "best guess" because there's no actual star on the CNP and, depending on how low a magnitude your scope and viewing conditions allow - you'll be guessing so as to get within a few arc seconds. Then move your scope straight down using the drive motor down arrow to horizontal. This will be way better than you've achieved so far, honest

HTH

[Bumfluff]

Hi all,

I got mine working a treat last night! What a great piece of kit this is!

Firstly to find my co ordinates I just googled "mytown (Alcester) co ordinates" and the wiki result gave them as degrees and minutes.

Secondly it doesn't seem to have an offline clock, so when I first set up last night I had to re edit the date and time, I also turned it off for a bit and when I turned it back on the time and date had rolled back to 24 may!? ( this caused my 2nd star alignment problem).

After sorting that, happy days!! The second star alignment was still slightly off but still in view of my finderscope. so as per instructions, nudge it into the centre with the buttons then set, and wa-hay setup successful.

[skywatcher250]

Ah that's a great idea. So using stellarium I should be able to reasonably accurately measure how far to turn it away from Polaris (not far) to the left or right, then level down to zero then turn the scope off then back on to polar align ? Then with hopefully the correct settings and coords start aligning again ? Gotta be what I do tonight. I Pray that it works this time. No point in looking for the ring nebula in just a black bit of space haha

Thankyou !!

[skywatcher250]

Amazing bumfluff. Did u line up celestial north then turn off and on ?I'm hoping to get it right tonight !!

[Bumfluff]

Yea I plonked it down in my garden, got it level using a spirit level app ok my phone. Set the date, time etc. Went for 2 star alignment. Vega as first star as its nice and bright and easy to see in the findersope, second star polaris tweak it to the centre of view, hit enter and sorted! When you get it done later check out M13, I was amazed by how good this object looks with this scope!

Happy hunting

[squeaky]

Yep.

Get a good CNP then put the scope horizontal and turn off.

Then turn on again, now go for two star alignment - ensuring that you have the right coordinates for where you are and that time and date etc are all correct.

If the second star doesn't show up in your finder scope there's every chance you've got something wrong unless it's only just outside the view.

Anyway, have fun

[skywatcher250]

bumfluff, did u use one of the included eyepieces for M13 ?

squeaky... I'm getting really excited now haha - i wish it was night !!!thanks again

[stev74]

Yep.

Get a good CNP then put the scope horizontal and turn off.

Then turn on again, now go for two star alignment - ensuring that you have the right coordinates for where you are and that time and date etc are all correct.

If the second star doesn't show up in your finder scope there's every chance you've got something wrong unless it's only just outside the view.

Anyway, have fun

I have the 300p and I believe you only have to put the scope horizontal and point it north if you are auto tracking only. For GoTo you only need to do brightest star or 2 star alignment and the scope will work fine and should be able to find any object in the database. Well as long as you input time, date, long/lat coordinates and level the scope correctly. There is no point giving yourself extra work if you don't need to.

Sent from my HTC Desire HD A9191 using Tapatalk 2

[squeaky]

yes, I agree with what you say about goto and tracking - but I found that tracking could be a bit iffy when only doing a two star - but seems much better if you start up with the scope already pointing north and horizontal.

I set mine to track a low eastern star the other day when we had a lot of haze, gave up and went to bed... five hours later the star was still centre view!

[skywatcher250]

hey - ok well I'm set up and now waiting haha !!!!!! thanks again - fingers crossed i get it right - just tried a v fast shot of the moon - nothing to clever and obviously the daylight contrast is pants haha

[squeaky]

Yep - pants

So come on then - we're all here holding our breath waiting to hear how you got on...

[skywatcher250]

no good sadly - the synscan went nowhere near where it was supposed to - have i possibly got a duff base unit as well... surely not !!!!!!

mate - thankyou so much for all your help too yesterday !!! invaluable - lets see what FLO tell me later on and go from there.... not an ideal start, but onwards and upwards

[squeaky]

Bummer.

Don't know what else to suggest, sorry.

[skywatcher250]

it should work.. just doesn't seem to ! ill get there at some point but gotta talk to FLO first to see what they say

thanks

[knobby]

it should work.. just doesn't seem to ! ill get there at some point but gotta talk to FLO first to see what they say

thanks

Si,

I've got my laser collimator in car with me today in case I'm near Loughton.

Could pop it in if you still want to try it?

Sent from my HD2Droid

[skywatcher250]

wow ! amazingly kind of you - thankyou - i can follow that vid link then !!! ill send you a message after talking to FLO - if they tell me to box it all up again etc then prob no point in grabbing it really - ill get back to u asap - thanks again

[knobby]

wow ! amazingly kind of you - thankyou - i can follow that vid link then !!! ill send you a message after talking to FLO - if they tell me to box it all up again etc then prob no point in grabbing it really - ill get back to u asap - thanks again

Pm'd you

Sent from my HD2Droid

[SeedyF]

no good sadly - the synscan went nowhere near where it was supposed to - have i possibly got a duff base unit as well... surely not !!!!!!

mate - thankyou so much for all your help too yesterday !!! invaluable - lets see what FLO tell me later on and go from there.... not an ideal start, but onwards and upwards

Uh-oh - this sounds a lot like the issue I had. I went through the set up routines time and time again and was absolutely sure I was doing everything right. But the goto would overshoot the 2nd object wildly. Eventually it dawned on me that I could test the motor's accuracy and if it was spot on I could go back to working out what I was doing wrong. The fault was in the motor (somewhere!!) and I had the whole mount replaced.

So here is what I did during the day;

1. Set up as normal but didn't star align (it was daylight after all )
   
2. Focussed the scope on a distant tree. It had a really distinctive knot quite high up.
   
3. I centred the eyepiece on the knot.
   
4. I recorded the co-ordinates displayed in the handset
   
5. I slewed the scope up in ALT by 20 minutes looking only at the handset display. I slewed back to the co-ordinates noted at 4 above.
   
6. Checked the knot was still centred. It was spot on.
   
7. Repeated this slewing away in AZ
   
8. Slewed back again only using the handset display and when it reached the AZ co-ordinate noted at 4 above checked the eyepiece and the eyepiece was not centred on the knot.
   
9. Actually I didn't need to look in the eyepiece, I could see the scope went way past the tree. My recollection was by about 15 degrees.
   

So my deduction was that the motor was travelling much further/faster than the encoders and handset thought. I contacted the supplier who arranged for it to be picked up, sent back to OVL and tested. They quickly came back and said the motor was faulty and shipped a replacement mount.

It now works like a dream and I have had several months thorough enjoyment. M13 nearly made me fall off my chair first time I saw it

PS - I saw your other posts and I have seen DSO images taken with a 300 version of our scope that are pretty amazing, maybe don't rush to get an EQ mount. I'll have to see if I can find a link.

[skywatcher250]

hey chris... wow now that is an experienced voice talking !

great idea ! i will do just that later on - when u say 20 minutes you mean on the coords ? surely if u slew 20 mins on the hand set both ways it will come to the same spot - do you mean it went faster one way than the other ?