Lunt 60mm Tilt Tune

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Bill_C
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Lunt 60mm Tilt Tune

Post by Bill_C »

Hi All
What advantage if any is a Pressure tuner over a Tilt tuner? Thanks in advance. Bill


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Bob Yoesle
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Re: Lunt 60mm Tilt Tune

Post by Bob Yoesle »

Pressure tuned etalons can theoretically be used at a greater range of altitudes (e.g. they are impervious to barometric pressure changes, which alter the etalon gap refractive index). Tilt-tuned etalons are more sensitive to altitude changes. If in a good range of tuning at sea level, going to higher altitude will reduce the refractive index of the etalon gap, and blue shift the etalon CWL. It would have a reduced tuning range, and may not even be able to get on band at much higher altitudes. However, this seems to be a rare event, and can be remedied with a tilt-tuned etalon with a different CWL.

Tilt tuned etalons therefore needed to also have much more stringent spacer thicknesses (CWL) to be usable at a range of altitudes, and some therefore feel they perform a little better than their PT cousins. There does seem to be a much wider variation in etalon CWL with PT etalons.

Bob


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Re: Lunt 60mm Tilt Tune

Post by marktownley »

Tilt tuned etalons can also show a more unevenly illuminated field of view if they require too much tilt to get them on band... This is the same for internal and external tilt tuned etalons...


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Re: Lunt 60mm Tilt Tune

Post by Bill_C »

Thank You Bob and Mark for the replies I live at about sea level and will be also using the scope at about 342m or 1122 feet .
I can retro fit the tilt tune to pressure and am wondering if it is worthwhile.
Thx Bill :beanie:


Lunt pressure tuned 60mm
Orion ST 80mm
Bausch and Lomb 90mm
Quark Chromosphere / 130mm ERF
Antlia 35mm prism with 1.25" cak filter
Starfield 2" herschel wedge
Celestron 10x42 white light binos
various Barlows and Filters
Player one :
Neptune M IMX 178m
Apollo M IMX 174m
Apollo Mini IMX 429m
Apollo -M Max IMX 432m
Sky Watcher SolarQuest
EQ 5 Black
User avatar
Bob Yoesle
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Re: Lunt 60mm Tilt Tune

Post by Bob Yoesle »

I'd wait to se how well it works - it could be and probably will be just fine.


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Re: Lunt 60mm Tilt Tune

Post by Bill_C »

Thank you Bob
Will be waiting on good weather nothing but rain right now


Lunt pressure tuned 60mm
Orion ST 80mm
Bausch and Lomb 90mm
Quark Chromosphere / 130mm ERF
Antlia 35mm prism with 1.25" cak filter
Starfield 2" herschel wedge
Celestron 10x42 white light binos
various Barlows and Filters
Player one :
Neptune M IMX 178m
Apollo M IMX 174m
Apollo Mini IMX 429m
Apollo -M Max IMX 432m
Sky Watcher SolarQuest
EQ 5 Black
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