newbie alert

Hi Leti... You be better off pulse guiding so not using the ST4 connection... You will need the ascom platform driver and the drivers for your guide cam installed regardless of how you guide benefits to pulse guiding are that you only have to calibrate once, with ST4 you have to calibrate every time on every target and after a flip.. plus if you bring up the drift align tool it will tell you where you're pointed so helps with calibration on equator

As a add on the newt style scope has a bigger central obstruction , where as the esprit doesn't have any, I'm sure there's a calculation out there to show the difference in brightness... If you want more reach for the smaller galaxies etc I'd look at the Rc or sct design

First aperture does nothing for the size of the target, it will be brighter thou.. FL gives the object size in the fov not aperture This shows what you have now to the quattro So the green box with the .77 reducer in place The red by taking it out and using it at it's native 1050 FL And the yellow with the 12 inch quattro For me not enough to warrant the extra expense, plus you would need a fairly decent mount to throw 12 inch X 1200 around, presume you have that... I've based it on the default camera in astronomy tools fov as you didn't say what camera you use

Don't think there's a guide assistant when using the air.... Don't think it uses the whole Phd package

Seen them like that using a OAG and guidecam, just needed a slight spacing adjustment... With my William optics 80 I had to use a adapter to produce the correct spacing... Are you using a reducer?

You obviously like them to buy another... Nothing to lose and alot to gain from a full strip down.... probably then run far better than it ever did... If you change all the bearings, washers the worst that could happen is maybe a new motor or board....

Indeed that's very odd, I've got a problem with the data board on my 460 which needs a trip to Portugal soon Before you go too in-depth I'd certainly eliminate the data cable, check the power supply and also I'd plug the data cable straight into the laptop rather than use a hub if you use one

You've not fitted the reducer the wrong way around have you? I've seen someone else do this, who's name I'll hide to save embarrassment....ehh Simon🫢

I've already said I can't see your signature as I'm viewing on a phone( you can't see this on a phone) What I don't get is why you're using a tele- extender and making your image small.. you want a reducer if anything... Only trying to help , won't take the trouble anymore

There's no horsehead image I can't see your signature as viewing on a phone

Yes I'm all in favour of using what you have..

Nothing here...

Lots of people

So from left to right.. first is to the middle left of the image and the rest are top left? How does the rest of the stars in the image look as from what you have looks confusing.. If it's drift it would usually be on one particular axis so stretched stars in 1 direction, if it's spacing it would show stretched stars pointing inwards if it's too close and going around the circumference if it's too far( you seem to have both)... With my William optics ed80 I thought I had tilt but it showed to be focuser tube sag as one of the bearings eventually gave up... William optics were just useless, blatantly said the focuser is no longer used, we don't have spares, can't help... ( Turned out to be a simple fix) So that's the last William optics scope that I buy

PTFE or teflon washers will be better than cork assuming the mating surface is for minimal friction, just make sure they're the same thickness As for a bigger worm, the drive system is calculated with components in the mount, if anything is changed, ie a bigger worm drive are you able to change this calculation to enable the mount to track or point if it's a goto... Assuming its not

That's just crazy...another old but still no slouch when it comes to using it

I was imaging this last night.. Won't look anything like yours thou... Great work with details I've never seen before,crisp, sharp and just awesome

As vlaiv has suggested , with a oag you need it set up correctly.. spacing needs to be correct to the imaging sensor, and dimensions from the prism to the imaging cam and the prism to the guide cam the same.. taking note the backfocus distance between cameras won't be the same.. I have the long side if the guide cam parallel to the long side of the imaging cam Then there's the prism depth, ideally take some flats to make sure it's not impeding into the light cone of the imaging cam.. I use 3 sec guide exposures , plenty long enough And make sure the focal length is entered correctly within phd

I use a 290m with a oag with my c8.. plenty sensitive enough, never had an issue with finding guidestars What camera are you using? And what oag?

Zoom as you put it is really FOV dictated by the sensor size... You can increase the fov by using a reducer but only by the size of the reduction, ie .8 , .6 etc Just check that you're not using ROI on your capture program as that could also have that effect

That T adapter would work with a Celestron reducer but it's a Antares one, which I'm sure that I've seen 85mm thrown about rather than the 105mm that Celestron spec... Have a little search on Mr google

Use a big bright star and up the iso on your camera .. longer exposure length also helps

You can do your dark Library and bad pixel map but I've found it better to do this outside You could focus on a distant object during the day but expect this to be different at night on stars