YouTube of my PST Sweet Spot Tweaks

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Starry Jack
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YouTube of my PST Sweet Spot Tweaks

Post by Starry Jack » Fri Jun 12, 2020 1:31 am

If you would, try this YouTube link of a video I made adjusting the PST Stage 2 Mod sweet spot. I've placed markers at each moment I moved the Etalon. Sometimes the "movement" was simple a micro move the opposite direction from whence I came.

https://youtu.be/MIW9DP8-AAI

For the life of me I don't know what 'sweet' really is.

By the way, the focuser is not strong enough to keep focus as I move the Etalon so it is a bit soft. This was shot as an SER 16bit "auto size" so part of the video is vignetted.

152mm f6.5 with a Baader 1.7 glasspath-->Original Etalon (old one)-->BF5-->12nm filter-->ASI174.

Thanks,


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marktownley
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Re: YouTube of my PST Sweet Spot Tweaks

Post by marktownley » Fri Jun 12, 2020 11:27 am

That tuning is bouncing round all over the place, how have you got it all connected together?


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Re: YouTube of my PST Sweet Spot Tweaks

Post by Starry Jack » Fri Jun 12, 2020 12:49 pm

Thanks, Mark...that's an artifact of the long optical train and the mount. The connections are all solid "screwed" or "glued". The unit is solid.

To move the Etalon I end up bouncing the scope and once I move the Etalon in one direction I can barely move it in the reverse direction which can result in a big change in the sweet spot.

Also since the unit is so heavy, the focuser slips a little bit so focus goes soft.

I can edit the video so I only grab stills at each marker.

Jack


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Quark Chromosphere f27 native, (f14 when focal reduced)
Mallincam .5x focal reducer (large format)
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Re: YouTube of my PST Sweet Spot Tweaks

Post by marktownley » Fri Jun 12, 2020 6:37 pm

How solid is the focuser? I think the back end has some tilt to it.


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Re: YouTube of my PST Sweet Spot Tweaks

Post by Starry Jack » Sat Jun 13, 2020 11:44 pm

You have a good eye, Mark. Yes the unit is so Ling it drools the focuser.

That said, I rotated the assembly a bit yesterday and seemed to remove some of the slop.


Explore Scientific 152mm f6.5 achromat
Aeries D-ERF
Quark Chromosphere f27 native, (f14 when focal reduced)
Mallincam .5x focal reducer (large format)
ZWO174 (IMX249 chip 5um)
Huge Sense of Adventure Viewing Creation

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