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Focusing NIGHTMARE with 6”SCT + ASI224


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Endless nights spent trying to focus and still nothing. It’s to the point where I loath getting the telescope out. I really enjoyed visual and wanted to take a picture of Jupiter with an actual planetary camera instead of holding my phone up to the eyepiece. It feels like the worst purchase I’ve made yet!

Current setup: Celestron 6”SCT, AVX mount, ZWO ASI224 colour. 

The issue seems to be focusing. I have yet to achieve focus on any object, whether that is the moon, a star or planet. Back focus is not as issue, I can find the target and make ‘doughnuts’ either side of the object using the focus knob. I’ve tried using a toothpick and elastic band for more precise focusing - nope. 
 

I invested in a RPi4 running astroberry with the intention of plate solving eventually but with zero focus it can’t solve anything so it’s rendered useless. I am at wits end with it all. I’ve connected the camera direct to my laptop and used it through astroberry. I’ve tried multiple programs, APT, Firecapture, OACapture.  I’ve watched video and video on YouTube how how to use the programs with without focus it’s impossible.
 

Should I look to get a motorised focused? Or will this be more money I am throwing away? 
 

ANY HELP, literally any is appreciated before I giving up completely. 

 

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55 minutes ago, lw2689 said:

Endless nights spent trying to focus and still nothing.

Hi Lou, I find with my 8se that you need to turn the focus knob very slowly, I use a clothes peg

Try it out during the day (if you haven't already) using your 25mm Plossl on a chimney pot or something else.

Maybe others can help more.

Edited by Mick H
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30 minutes ago, Mick H said:

Hi Lou, I find with my 8se that you need to turn the focus knob very slowly, I use a clothes peg

Try it out during the day (if you haven't already) using your 25mm Plossl on a chimney pot or something else.

Maybe others can help more.

Hi Mick. Thanks for your reply. Focusing with an eye piece in is really easy to achieve but near impossible when using the planetary camera :(. I’ve tried using an elastic band with a tooth pick similar to the clothes peg idea but it’s all one fuzzy blob

 

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Hi have the ASL224mc i have used it on my 8 inch Newtonian i use sharpcap and not really had a problem with focus 

I start with an eyepiece focus it then remove it pop camera in and if it needs a tiny adjustment  to the focus its only a touch 

I have used camera in 125 nose piece and also in 2 inch mode focus can be a little fiddly but does not need much 

Are you using an AR cut filter 

Edited by Neil H
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23 minutes ago, lw2689 said:

Focusing with an eye piece in is really easy to achieve but near impossible when using the planetary camera

Sorry I did not realise your problem is with the camera, hopefully the astrophotographers can help.

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2 hours ago, lw2689 said:

ANY HELP,

Hi

Are we sure that the camera is working correctly?

Can you get the 224 attached to another, preferably short focal length, telescope? Focus with low/auto gain in daylight on a distant tree/pylon/building...

Cheers

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If using the moving mirror focuser it is vital to make the last adjustment a push of the mirror up the tube. If you do the reverse the mirror may take a while to drift back down the tube to catch up with the mechanism, so changing the focus as it does so. On most SCTs, I think, that means turning the knob anti-clockwise as the last operation. Check this for your instrument. It is certainly better, when imaging, to lock the mirror close to critical focus and to use a back-mounted conventional focuser.

But... when the seeing is bad there is nothing you can do. Have you tried focusing on a star to see how consistently that behaves?

Olly

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