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  #261  
Old 23-06-2019, 01:04 PM
Stefan Buda
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Quote:
Originally Posted by multiweb View Post
Hi Stefan, good to see you again up and about.
You have a heating pad for the secondary and fans only for the primary, correct?
Heating pad for the secondary and also heaters in the air stream for the primary, but only about 6 Watts, just enough to provide dry air in the morning. See earlier pictures.
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Originally Posted by gregbradley View Post
I am curious. What does overcooling the secondary do? I thought the cooler the better when it came to mirrors or is it more the cooler the better so long as the secondary and primary are in sync with regards to ambient?

Does it make the secondary shift shape slightly compared to the primary?

Greg.
Greg,
By overcooling I mean getting bellow ambient or very close to it. It happens because the secondary assembly is radiating away its heat to a very cold sky and can easily drop below ambient. The same reason you get ice on top of your car when the ambient is still a few degrees above zero. The secondary itself is only 14mm thick in the center and will not develop much of a thermal gradient that would cause shape shifting. If there is a small change in focal length, the auto focus should deal with it. I will set the controller to maintain the secondary at about 1.5 degrees above ambient. That may not be worm enough to prevent dew in some conditions but it will not produce a heat plume either. A humidity sensor would allow the calculation of the dew point, but at this stage I want to avoid using one.
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  #262  
Old 07-09-2019, 07:11 AM
Stefan Buda
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Made my own dovetail base, to fit the slots in the mounting bar.
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  #263  
Old 02-11-2019, 06:37 AM
Stefan Buda
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Serial Number 001 is now installed in an automated observatory in country Victoria.
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  #264  
Old 02-11-2019, 08:17 AM
sharpiel (Les)
The Birdman

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Looks as good as, if not better, than top end commercial units.

That AP mount looks right at place underneath. An exquisite job as usual from a master builder.
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  #265  
Old 02-11-2019, 08:50 AM
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Atmos (Colin)
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Incredible build Stefan, it’s come up very nice!
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  #266  
Old 03-11-2019, 07:12 AM
Stefan Buda
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Thanks guys.

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Originally Posted by sharpiel View Post
Looks as good as, if not better, than top end commercial units.
I hope so, as I designed it from the start to be a commercial product if there is demand for it. But I won't start advertising it as such until serial number 002 is completed. That will not happen until mid next year because of other work commitments. Meanwhile I also want to bring up the prototype (SN 000) to the same standard with the electronics as SN 001.
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  #267  
Old 03-11-2019, 07:33 AM
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multiweb (Marc)
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Awesome product.
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  #268  
Old 03-11-2019, 09:21 AM
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strongmanmike (Michael)
Woohoo it's clear

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Beautiful looking (and performing) bits of kit there Mr Buda
Mike
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  #269  
Old 07-11-2019, 10:05 AM
TWF (Tom)
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CDK250#001 First Light

First light image from BeamTech CDK250 #001.

This image is a calibrated stack of 77 x 240 sec Lum exposures. No further processing applied.

The scope is exceeding all expectations, particularly the time honored ability for new equipment to generate cloud!
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  #270  
Old 07-11-2019, 02:20 PM
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multiweb (Marc)
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Originally Posted by TWF View Post
First light image from BeamTech CDK250 #001.

This image is a calibrated stack of 77 x 240 sec Lum exposures. No further processing applied.

The scope is exceeding all expectations, particularly the time honored ability for new equipment to generate cloud!
Beautiful!
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  #271  
Old 07-11-2019, 07:49 PM
Stefan Buda
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Quote:
Originally Posted by TWF View Post
First light image from BeamTech CDK250 #001.

This image is a calibrated stack of 77 x 240 sec Lum exposures. No further processing applied.

The scope is exceeding all expectations, particularly the time honored ability for new equipment to generate cloud!
Thanks Tom for the feedback, and welcome to IIS.
I'm sure you will also get good feedback regarding processing if you post future images in the deep sky section.
This Lum image looks like a promising start, but I don't know how you managed to accumulate 5 hours worth of clear sky. I had to abandon all my attempts of travel to Haethcote because of predicted high level haze.
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  #272  
Old 09-11-2019, 01:21 PM
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Troy
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What everyone else said looks good
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