Ruler as an Optical Scale

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mikemarotta
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Ruler as an Optical Scale

#1

Post by mikemarotta »


Squinting is hard work and I often view with both eyes open. Last night, it occured to me to use a millimeter scale to help with ratio and proportion. I sketched Epsilon Lyrae. I set the ruler at a comfortable bent-arm's-length so that the distance between E1 and E2 was 2 cm. With that, I was able to get a better guesstimate of the layout of the nearby stars. Later today, I will goto see about buying a large sheet of something black to set up as a backdrop.

(ES 102 mm refractor. f/6.47 with 32mm ocular with 2x Barlow.)
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Michael E. Marotta
Astro-Tech 115 mm APO Refractor Explore Scientific 102 mm f/6.47 Refractor Explore Scientific 102 mm f/9.8 Refractor Bresser 8-inch Newtonian Reflector Plössls from 40 to 6 mm Nagler Series-1 7mm. nonMeade 14 mm. Mounts: Celestron AVX, Explore Twilight I Alt-Az, Explore EXOS German Equatorial
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John Baars Netherlands
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Re: Ruler as an Optical Scale

#2

Post by John Baars »


Well done and a good idea!
Be sure to have the same observing distance to the ruler. IMHO a stretched arm will always give the same results for you.
With a refractor and a zenith prism or diagonal one can even have one eye on the ruler and the other at the object. ( OK, it will cost some exercise)
Once the lay-out of the brightest stars in the eyepiece field is sketched, the rest may become more easy. ( without the ruler)
Thanks for your nice tip for sketchers!
Refractors in frequency of use : *SW Evostar 120ED F/7.5 (all round ), * Vixen 102ED F/9 (vintage), both on Vixen GPDX.
GrabnGo on Alt/AZ : *SW Startravel 102 F/5 refractor( widefield, Sun, push-to), *OMC140 Maksutov F/14.3 ( planets).
Most used Eyepieces: *Panoptic 24, *Morpheus 14, *Leica ASPH zoom, *Zeiss barlow, *Pentax XO5.
Commonly used bino's : *Jena 10X50 , * Canon 10X30 IS, *Swarovski Habicht 7X42, * Celestron 15X70, *Kasai 2.3X40
Rijswijk Public Observatory: * Astro-Physics Starfire 130 f/8, * 6 inch Newton, * C9.25, * Meade 14 inch LX600 ACF, *Lunt.
Amateur astronomer since 1970.
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