Getting Focus with Atk 314L + Pro

[valleyman]

Ok got out tonight for the first time with the Atik on my SW 80 ED Pro and could not just get focus. Using Artemis I followed the instruction about starting and switched on the Camera.

 

I had practised during the day on a distant object and had all the extension tubes fitted to get focus.

 

With the Camera switched on all I had on the screen was a mass of colours. No star (Arcturus) I started playing with the exposer times and took it down to .02 sec which got rid of the colours and gave  me a view of the star, started focusing it but could get it no smaller than a 1/4" disc. Gave up and switched to Nebulosity. Managed to get the star down to a dot using the focuser and the Black and White sliders, tried switching that to Auto but did not get any better.

 

Had about 15 minutes playing with that but then the clouds rolled in and that was it for the night.

 

Any advice with what the settings should be to get the pin point stars or what knobs should be tweaked, would be greatly appreciated.

 

 

Pat

[lensman57]

Ok got out tonight for the first time with the Atik on my SW 80 ED Pro and could not just get focus. Using Artemis I followed the instruction about starting and switched on the Camera.

I had practised during the day on a distant object and had all the extension tubes fitted to get focus.

With the Camera switched on all I had on the screen was a mass of colours. No star (Arcturus) I started playing with the exposer times and took it down to .02 sec which got rid of the colours and gave  me a view of the star, started focusing it but could get it no smaller than a 1/4" disc. Gave up and switched to Nebulosity. Managed to get the star down to a dot using the focuser and the Black and White sliders, tried switching that to Auto but did not get any better.

Had about 15 minutes playing with that but then the clouds rolled in and that was it for the night.

Any advice with what the settings should be to get the pin point stars or what knobs should be tweaked, would be greatly appreciated.

Pat

Hi Pat,

Centre the star in a high power eyepiece, then swap to the ccd and turn the camera on . Start Artemis capture and make sure that it has detected the camera, click the preview and choose a 1s exposure and click the loop button at the top. Adjust the focus slowly till you get an image of the star, if the star is way out of focus you don't get any thing first but as you get close you should get the diffraction rings and then gradually the star snaps into rough focus. Once in rough focus draw a preview rectangle around the star and double click on the star, the FWHM window opens up and then using the micro adjuster fine tune the focus for the smallest FWHM value. Personally I use Nebulasity for my captures now the focus routine is similar but quicker in my opinion.

Regards,

A.G

[ollypenrice]

I agree with AGs description, though once you have an idea of focus you can mark the drawtube with a pencil and dispense with taking out the camera, which is something I avoid where possible. Mine live in the scopes.

I suspect you had a setting wrong somewhere, maybe just the visualization which is controlled by the 'Log' slider. Or could your focuser have been slipping so that while you thought you were moving the drawtube you maybe weren't?

Olly

[SimonfromSussex]

Pat the other thing to say is that, I found with the atik 314, a bright star would be quite large on screen, i.e. it would not reduce down to a pin point.

You just need to get it as small as possible, so you will be in focus when you roll focus one way it gets bigger and if you roll it the other way it gets bigger as well.

I cannot recommend a bahtinov mask enough, they are not expensive and would help enormously to conform the focus point which you can then lock off.

[valleyman]

Thanks guys for the help. What you say Simon is more or less what was happening.

Will pick a smaller star next time Lensman, your advice is good, did most of what you said except for the Preview bit.

Was getting close to asmaller image with Nebulosity but the clouds rolled in