Difference between revisions of "August 13, 2013"

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=Optical Magic=
 
=Optical Magic=
 
 
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<em>image by [mailto:gari@adbooth.net Gari Arrillaga], Salou, Spain</em><br />
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<em>image by [mailto:gari@adbooth.net" rel="nofollow Gari Arrillaga], Salou, Spain</em><br />
 
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<br />
 
Over LPOD's 10 years there have been a small number of superb imagers who have not just luck, but the skill, equipment and technique to continually <br />
 
Over LPOD's 10 years there have been a small number of superb imagers who have not just luck, but the skill, equipment and technique to continually <br />
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and has sent a comparison of imaging close to the horizon with and without it. The difference is remarkable, transforming a poor image into quite a <br />
 
and has sent a comparison of imaging close to the horizon with and without it. The difference is remarkable, transforming a poor image into quite a <br />
 
respectable one. Gari's diagram at top right shows how the ADC works. It contains two counter-rotating prisms that are adjusted to reduce or eliminate the<br />
 
respectable one. Gari's diagram at top right shows how the ADC works. It contains two counter-rotating prisms that are adjusted to reduce or eliminate the<br />
red-blue edges often seen on bright objects. Gari uses an ADC sold by [http://www.pierro-astro.com/accessoires-optiques/correcteurs-reducteurs/a-d-c-correcteur-de-dispersion-atmospherique.html Pierro Astro], and Leo's ADC is from [http://www.astro-electronic.de/wedge.htm Astro Electronic]. These ADCs may be <br />
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red-blue edges often seen on bright objects. Gari uses an ADC sold by [http://www.pierro-astro.com/accessoires-optiques/correcteurs-reducteurs/a-d-c-correcteur-de-dispersion-atmospherique.html" rel="nofollow Pierro Astro], and Leo's ADC is from [http://www.astro-electronic.de/wedge.htm" rel="nofollow Astro Electronic]. These ADCs may be <br />
 
very useful for observers who live in high latitudes, where the Moon and planets are too often at low atlitudes. The ADC may also be a relatively easy way<br />
 
very useful for observers who live in high latitudes, where the Moon and planets are too often at low atlitudes. The ADC may also be a relatively easy way<br />
to correct an otherwise good achromat marred by color fringes. And I really wish that Greenacre and Barr, who observed red &quot;[http://www.the1963aristarchusevents.com/JBAA_123-4_OConnell.pdf volcanic eruptions]&quot; at the<br />
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to correct an otherwise good achromat marred by color fringes. And I really wish that Greenacre and Barr, who observed red &quot;[http://www.the1963aristarchusevents.com/JBAA_123-4_OConnell.pdf" rel="nofollow volcanic eruptions]&quot; at the<br />
 
Cobra Head in 1963 with the Lowell 24&quot; refractor at low elevation, had an ADC. (Although, perhaps it would correct away real color, too!)<br />
 
Cobra Head in 1963 with the Lowell 24&quot; refractor at low elevation, had an ADC. (Although, perhaps it would correct away real color, too!)<br />
 
<br />
 
<br />
<em>[mailto:tychocrater@yahoo.com Chuck Wood]</em><br />
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<em>[mailto:tychocrater@yahoo.com" rel="nofollow Chuck Wood]</em><br />
 
<br />
 
<br />
 
<strong>Related Links</strong><br />
 
<strong>Related Links</strong><br />

Revision as of 22:48, 4 January 2015

Optical Magic

LPOD-Aug13-13.jpg
image by " rel="nofollow Gari Arrillaga, Salou, Spain

Over LPOD's 10 years there have been a small number of superb imagers who have not just luck, but the skill, equipment and technique to continually
produce outstanding lunar images. Based on the images that Leo Aerts of Belgium has submitted over the last 2 months I think he is in that pantheon of
great lunar imagers. In a recent LPOD he responded to my request to describe his equipment and technique so that others mght learn from his exper-
ience. One thing that struck me as being different from most imagers was the use of an atmospheric dispersion corrector (ADC). Gari also uses an SDC
and has sent a comparison of imaging close to the horizon with and without it. The difference is remarkable, transforming a poor image into quite a
respectable one. Gari's diagram at top right shows how the ADC works. It contains two counter-rotating prisms that are adjusted to reduce or eliminate the
red-blue edges often seen on bright objects. Gari uses an ADC sold by " rel="nofollow Pierro Astro, and Leo's ADC is from " rel="nofollow Astro Electronic. These ADCs may be
very useful for observers who live in high latitudes, where the Moon and planets are too often at low atlitudes. The ADC may also be a relatively easy way
to correct an otherwise good achromat marred by color fringes. And I really wish that Greenacre and Barr, who observed red "" rel="nofollow volcanic eruptions" at the
Cobra Head in 1963 with the Lowell 24" refractor at low elevation, had an ADC. (Although, perhaps it would correct away real color, too!)

" rel="nofollow Chuck Wood

Related Links
21st Century Atlas chart 9.