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Filter Slider System,
More UHC Filter Tests

Posted: 3 September 2020

After last night's successful eyepiece focus test with the Starizona Filter Slider System, I called Starizona to find out if they had a M42-SCT adapter for their Filter Slider System. After checking they confirmed that they had one in stock. They also had filter trays (I wanted a fourth tray) and a 2"-1.25" filter adapter in stock. Laurraine picked up all three items for me.

Open: Wednesday, 2 September 2020, 1805 MST
Temperature: 86°F
Session: 1512
Conditions: Clear, breezy

12" f/8 LX600 w/StarLock
2" 24mm UWA eyepiece
1.25" 26mm eyepiece
2" 14mm 100° eyepiece
2" 5.5mm 100° eyepiece
Filter Slider System

iPhone 11 Pro Max

I tested the M42-SCT adapter on the Filter Slider System. It worked to attach a SCT visual back onto the holder, seen here using a 1.25" 26mm eyepiece, with and without the filter tray in place.


There was only one problem; the 1.25" tube was loose as the SCT ring could not be fully tightened down. I needed a spacer. I found a rubber washer that fit perfectly without blocking any light. Adding that eliminated the problem. I also tested the 2"-1.25" filter adapter with my six 1.25" filters. I was disappointed to discover that my four colored filters were too tall to slide into the filter holder. My other two 1.25" filters, an old Scopetronix Moon Filter and an Astronomik Hydrogen-Beta Filter, were usable with the Filter Slider System. I may look at replacing the colored filters with smaller sizes.

1836 MST: I began relaxing on the observatory patio bench. It is a nice way to "watch the stars come out".

1847 MST: sunset.

1904 MST: had a visitor.


1930 MST: back inside the observatory.

1933 MST: LX600 ON, StarLock OFF, High Precision OFF.

Viewed Jupiter and three moons, 102X.

Mounted the Filter Slider and 26mm eyepiece. Viewed Jupiter and Saturn, 94X, without a filter. Using an eyepiece with the Filter Slider worked wonderfully.

I then began doing more visual tests of the Explore Scientific 2" UHC Filter for my upcoming review. I viewed several Deep Sky Objects with and without the filter. Using the Filter Slider System made it very easy to compare the views with and without the filter by sliding the filter tray in and out.

1944 MST: the eastern sky was brightening from the rising just past full Moon.

2002 MST: dome OFF (onto the PZT).

2006 MST: the breezes were calm now.

2008 MST: I completed my visual tests of the UHC Filter. I plan to do imaging tests on the next session.

Viewed M57 (Ring Nebula), 102X, 174X, and 443X. The view with the Explore Scientific 2" 14mm 100° eyepiece was great.

Viewed Jupiter and Saturn, 174X and 443X. Seeing was not quite good enough for 443X, but the planets were gorgeous at 174X.

2034 MST: dome ON.

Final look at Saturn, 102X.

2036 MST: LX600 OFF.

2040 MST: the Moon was rising over the hill.

Close: Wednesday, 2 September 2020, 2048 MST
Temperature: 76°F
Session Length: 2h 35m
Conditions: Clear

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