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6" F/9 Triplet Refractor OTA - *** sold ***

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6" (154mm) F/9 (approximate) Triplet Refractor OTA - lens by R. Christen, founder of Astro-Physics.

Lens is marked as: 6024 Sept. 84 R. Christen CT8.20

I do not know, and have not exactly measured the focal length of this instrument, but based on the tube length, I believe it to be approx. F/9

Previous owner(s) must have cleaned front element (sky facing) of lens, as there are streaks and blemishes visible. This defect does not appear to detract from the images obtained with the instrument. I have attached a photo that captures (as best as I can obtain) the front of the lens. I have only cleaned the lens front a couple of times using distilled water only. I removed the lens from the cell to obtain the attached photos, but have never separated the lens elements.

Tube is aluminum, white exterior, black interior, with dew shield (9"). Focuser is 2" Dobbins Instruments, rack & pinion.

I purchased the OTA in 1994 from an amateur in northwestern NM. I believe I am the third owner of this scope, but cannot prove. Non-smoker. Always stored inside air conditioned & heated space.

Sale includes :
* 6" (154mm) F/9 (approximate) OTA. Tube is 173 mm ID. Distance from the front
of the lens cell to the rear of the focuser is 1310mm
* 2" star diagonal w/ 1.25" adapter
* Explore Scientific 8 x 50mm Straight Thru Finder w/ Illuminated Reticle (6
degree FOV) & rings. Produces right-side-up images.
* 3" (80mm) Guide scope, approx. focal length F/7, w/ 1.25" rack & pinion
focuser, w/ 1.25" star diagonal, w/ TeleVue 9mm Ortho Illum. Reticle eyepiece.
Distance from lens to rear of focuser is approx. 19.5" (480mm)
* 6" Thousand Oaks Optical Solar Filter

I would prefer local pickup & examination, but would consider meeting within approx. 500 miles of the New Orleans, LA area to perform exchange.
If paying with PayPal - please add fees.
I have additional photos available if interested, please send private message for additional photos or info.

Mike Harang