Editing Talk:1791: Telescopes: Refractor vs Reflector

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Nitpick:  The refracting telescope, drawn correctly, has a mirror in the optical path (image inverter), but it is made with a special vampire reflecting material Ichorium. {{unsigned ip|162.158.74.219}}
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Nitpick:  The refracting telescope, drawn correctly, has a mirror in the optical path (image inverter), but it is made with a special vampire reflecting material Ichorium.
 
:Doesn't the one in this image have a mirror too? at the bottom to make the image come out at the side instead of the end? [[Special:Contributions/162.158.89.187|162.158.89.187]]
 
:Doesn't the one in this image have a mirror too? at the bottom to make the image come out at the side instead of the end? [[Special:Contributions/162.158.89.187|162.158.89.187]]
  
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Aren't there Space Vampires in Lovecraft somewhere? [[Special:Contributions/162.158.214.34|162.158.214.34]] 22:48, 27 January 2017 (UTC)
 
Aren't there Space Vampires in Lovecraft somewhere? [[Special:Contributions/162.158.214.34|162.158.214.34]] 22:48, 27 January 2017 (UTC)
Not as such, but there are in the classic ''Queen of Blood'' [http://www.imdb.com/title/tt0060877/] and in the unfortunate "Lifeforce" [http://www.imdb.com/title/tt0089489/] .  A refractor though should be able to see their interstellar umbrella [https://pluckyoutoo.files.wordpress.com/2008/08/lf17.jpg] [[User:Anthony11|Anthony11]] ([[User talk:Anthony11|talk]]) 07:05, 30 January 2017 (UTC)
 
:Colin Wilson also wrote a novel titled ''The Space Vampires''. https://www.goodreads.com/book/show/869314.The_Space_Vampires [[User:Nitpicking|Nitpicking]] ([[User talk:Nitpicking|talk]]) 03:38, 6 March 2022 (UTC)
 
  
 
An important advantage of refractors that keeps them popular is the very tiny amount of internal scattered light compared to reflectors. This really stands out when viewing planets and bright objects. Everybody loves that velvety black background field that refractors can provide. [[User:ExternalMonolog|ExternalMonolog]] ([[User talk:ExternalMonolog|talk]]) 09:59, 28 January 2017 (UTC)
 
An important advantage of refractors that keeps them popular is the very tiny amount of internal scattered light compared to reflectors. This really stands out when viewing planets and bright objects. Everybody loves that velvety black background field that refractors can provide. [[User:ExternalMonolog|ExternalMonolog]] ([[User talk:ExternalMonolog|talk]]) 09:59, 28 January 2017 (UTC)
 
Another issue with reflecting telescopes (though not pertinent to the joke) is that when used as a lens in photography, the bokeh, or unfocused highlights beyond the depth of field in an image, are rendered as circular 'doughnut' shapes, instead of the fuzzy points of light created by refracting lens systems. Run-on sentences, FTW. [[User:These Are Not The Comments You Are Looking For|These Are Not The Comments You Are Looking For]] ([[User talk:These Are Not The Comments You Are Looking For|talk]]) 01:20, 29 January 2017 (UTC)
 
 
Strictly speaking, bokeh is the "quality" of the OOF areas, not the areas themselves. [[User:Anthony11|Anthony11]] ([[User talk:Anthony11|talk]]) 07:05, 30 January 2017 (UTC)
 
 
There can be no doubt that the original comic contains a *mirror*, not a prism. And a porro prism would not even work, because it reflects the projection by 180 degrees! Porro prisms are always used in pairs, to upright an image *without* changing the viewing direction! --[[Special:Contributions/162.158.89.43|162.158.89.43]] 12:26, 30 January 2017 (UTC)
 
::The lens of a refractor flips the image, so having a single prism would render it upright.[[Special:Contributions/172.68.90.46|172.68.90.46]] 01:48, 31 January 2017 (UTC)
 
 
These days, Chernobog may be better known as Czernobog, from Neil Gaiman's novel [[American Gods]].  [[Special:Contributions/162.158.88.254|162.158.88.254]] 14:11, 1 February 2017 (UTC) Paul
 
 
It is odd that apochromatic refractors are not mentioned. These have much better color correction than achromatic telescopes. Further, contrary to the article's claims, refractors ARE widely used by amateur astronomers--especially for photography. There are several reasons for this, including that refractors are physically more compact, generally have give higher contrast images, and do not require collimation. Most important, though, is that they generally have shorter focal lengths than reflecting or catadioptric designs. This results in lower magnification and a wider field of view. This is helpful not only because many deep sky objects have a large angular size, but because highly accurate tracking is required to prevent star trails at higher magnifications. A google search will confirm that many experts in astrophotography recommend refractors (esp. for beginners). Cheers.
 

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