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I badly needed a quick look, white light solar scope to check for visible surface features [spots, etc.]
The observatory now houses only the 6" f/10 H-alpha scope. Changing it to white light is possible but takes several minutes. Which also undoes the well proven filter stack and denies me a focuser.
It also means opening up the observatory. Then removing the entire tail end of the 6" telescope and switching on the drives. With the sun at a minimum it often isn't worth the effort.
I'd need a solid mounting for the Vixen 90 f/11. Which is much too long to sit comfortably on my video tripod with pan and tilt head. So I opted for my APO spotting scope on its Manfrotto CF tripod and CF Sirui, gimbal mounting.
The Kowa TS-884 provides a nicely sharp image up to 96x with 1.6x extender. [Barlow] With only a hint of atmospheric dispersion. The downside is it is straight through 'scope [rather than bent] and does not have enough inward focus for a diagonal. Neck wringing is no fun [at all] at my age. Best used early and late in the day while the sun is still up.
I found a piece of PVC drainpipe which fitted the Kowa's sun shield nicely. All except for the protrusion of the moulded rubber, aiming sight on the sun shield. I had no plans to shave off the moulded sight so I grooved the inside the pipe off-cut instead. I started with a shallow hacksaw cut and then widened it with a range of coarse files. After turning both ends square in the lathe I finally smoothed it all over with sandpaper and gave it a wash to remove the dust. It now fits the Kowa sun-shield like a glove.
A strip of double sided, foam backed tape was stuck around the business end. The pipe off-cut then lowered gently onto the foil and then the foil lifted a little at a time to stick to the tape. A final turn [or two] of bright yellow, electrical tape ensured security of the solar foil and was a clear indicator of the filter being fitted to the telescope for safe, solar use. The wrinkly appearance of the filter foil is not deliberate but does not matter. Only perfect flatness is to be avoided for optical reasons.
I have found a food storage tube into which the new filter will fit safely. The filter rests on the lid of the inverted tub. With the tub lowered over it and pressed into the snap-on lid. This avoids having to find an oversized storage container to drop the solar filter into the depths. With the constant risk of damage to the foil during extraction. Moreover, no dust can settle on the foil in the inverted, storage arrangement. The tub is a bit tall but does no harm and cost practically nothing.
A strip of double sided, foam backed tape was stuck around the business end. The pipe off-cut then lowered gently onto the foil and then the foil lifted a little at a time to stick to the tape. A final turn [or two] of bright yellow, electrical tape ensured security of the solar foil and was a clear indicator of the filter being fitted to the telescope for safe, solar use. The wrinkly appearance of the filter foil is not deliberate but does not matter. Only perfect flatness is to be avoided for optical reasons.I have found a food storage tube into which the new filter will fit safely. The filter rests on the lid of the inverted tub. With the tub lowered over it and pressed into the snap-on lid. This avoids having to find an oversized storage container to drop the solar filter into the depths. With the constant risk of damage to the foil during extraction. Moreover, no dust can settle on the foil in the inverted, storage arrangement. The tub is a bit tall but does no harm and cost practically nothing.
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