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What am I doing wrong?


Guest VikN46
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Guest VikN46

Hi all I was wondering if you could help me.


 


I am still no nearer getting my guiding set up to work and now feeling so fed up with it.


 


I am using a QHY5L -II camera.


 


And have tried with both a 9x50 finder and using my travel scope the SW ST80 (on the off chance it was the finder as the ST80 would be too heavy to use on my mount I think).


 


Have tried using both PHD ver 1.14 and Metaguide


 


I can focus in the daytime and get a really nice clear images of a distant tree and at night a distant street light.


 


I just can't seem to figure out why I cannot focus on the stars I actually cannot see any stars at all, when I use an eyepiece they are there but when I change it for the camera nothing.


 


I have tried just the camera


 


I have tried adding a 2x barlow as an extension (lens removed)


 


just to name a few things I have tried. I am assuming it is down to a focus issue as everything works.


 


Could anybody give me a step by step idiots guide or different options to try to get this working feeling pretty defeated at the mo been trying to get it working for the past month but with no success. I really hope its just something I am doing wrong. :wallbash:


 


Thanks in advance.


 


Vik


 


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Do you have T-thread spacers on the ST80? It needs 13.5cm of back focus. Also a bhatinov mask is useful to get the focus spot on. :)


 


(Which finder/guider is it?)


Edited by Brantuk
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Guest Kheldar

Do you have T-thread spacers on the ST80? It needs 13.5cm of back focus. Also a bhatinov mask is useful to get the focus spot on. :)

 

I think you're confusing back focus requirements (important for flatteners) with scope focal point here Kim

 

To get a QHY to focus on an ST80 you either need a diagonal in the chain or a good 80mm T2 extension

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Mines hooked up directly to the focus tube Stephen (ie without diagonal). When you take the diag out it needs the tube extending 80-90mm. So when you focus - the camera is 13.5mm from the end of the scope (where the T-thread is). So yeah - we are in agreement. :)

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Guest Kheldar

Mines hooked up directly to the focus tube Stephen (ie without diagonal). When you take the diag out it needs the tube extending 80-90mm. So when you focus - the camera is 13.5mm from the end of the scope (where the T-thread is). So yeah - we are in agreement. :)

 

:highfive:

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Guest VikN46

I have used the extension that came with the camera and a 2x barlow with the lens removed to extend it further, is this too much or could this work?


 


or should I get one of these? I it is the right thing that is.


 


http://www.firstlightoptics.com/adaptors/baader-t2-extension-tube.html


 


 


Thanks all :)


Edited by VikN46
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I had a similar problem gaining focus with my ASI130MC when using it with my 200P and a 4x powermate when imaging planets. It is just a case of experimenting with various length extension tubes until you get it to work-or it was for me anyway. You'll get there :)

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Guest Kheldar

I have used the extension that came with the camera and a 2x barlow with the lens removed to extend it further, is this too much or could this work?

 

or should I get one of these? I it is the right thing that is.

 

http://www.firstlightoptics.com/adaptors/baader-t2-extension-tube.html

 

 

Thanks all :)

 

Barlow tube alone should be around the correct length.

 

All I can offer at this point is to move through the focuser travel very carefully and slowly. Set a 2s exposure in PHD

Edited by Kheldar
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stick in the diagonal that comes with the st80, does the job and will get you going and save you a few quid.


using PHD 1.4, there are a few options in camera selection, if it`s a ascom compatable camera have a go on that selection, set exposure to 1 second and move the slider to darken the back ground alittle so it`s not too grey, set it running and move the focuser on the st80 in alittle each time then wait to see if you can see anything appear, bit of a pain but when i was using the philips webcam to guide with the focus point was so small it was easy to go past it, once you have focus, i marked the draw tube of the st80 with black marker pen for future referance.


worth googleing the topic of using a qhy5 camera for guiding, make help with some settings and exposure times recommended for the camera.


don`t give up it`ll be worth it in the end.


Edited by red dwalf
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I got the finderscope adaptor from Modern Astronomy, removed the angled eyepeice from the finderscope and screwed this on then the QHY5 direct onto that.The only focusing i had to do was adjust the front lens of the finderscope to get decent stars. PHD 1.4 worked almost straight away, I had to adjust the gain but works very well!!


 


Cheers


Ron


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I use a QHY5 on an ST80 with a 2x barlow (lens removed) and its almost at the limits of its outward travel to get focus.


I use PHD, when connecting I select ASCOM camera and a box pops up with QHY5 with OK and Properties buttons, select properties and a new pop up appears - Gain, I set mine to 95% then click OK and its into PHD.


With it set to 1 second you should be seeing stars on the display.


 


Hopefully that helps, bear in mind mine isn't a QHY5II.


Edited by andyboy1970
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Just to add my 2 p


Instead of going straight for a guide star start with trying to focus on the moon.


I mean it is not like you can miss that and once you have achieved a good focus it is not too much to adjust it to focus on a star.


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Guest ecopley

You could try to find focus using sharp cap or something like it. You might find that tinkering with the settings allows you to get faster feed back while you are focusing. One you've done that you can switch back to phd or metaguide knowing that you should be focused and then find the right settings in you guide program.

You will probably still need the extension tube but it's very frustrating trying to focus at one frame every two seconds.

Just a thought.

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I have several T shirts. They all come from the land of "Tried to short cut getting focus at the start of the night".


 


Some of them are wet because it started to rain before I got focus.


 


Even if it takes 20s per sub I will personally, tweak focus, tweak focus.................... do it. Because after 6 hours you will be immensely p'd off when they are all out of focus.


 


Just my 2p worth!

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Guest ecopley

I completely agree that there's no short cut. Just that it might be easier to find your image if you can see nearer to real time.

Not a short cut, just a section of motorway in between the slow roads :)

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