Overall Rating: No Vote Weight: <none> Date: 09/28/2001 10:18:25 pm PST By: Anonymous (xxx.xxx.134.49) Link to this vote: http://www.excelsis.com/1.0/displayvote.php?voteid=40113
>No ED-doublet refractor should ever be called "apochromatic"! Not even the fluorite-doublets are! True apochromatic refractors are of true triplet or quadruplet design - which for example excludes doublets with additional field flattener lenses... The above is a political statement more than a rating of the product. With modern glass and lens design it is possible to build an APO in a doublet configuration. The ED114SS review in S&T (5/02) called it an APO and compared it to other APO scopes. Some quotes from the article: "Jupiter looked neutral white when sharply focused, with no surrounding halo of blue light, remarkable for such a fast-foca-ratio refractor." "Bright 1st-magnitude stars appeared clean white, with no halos from chromatic aberration." This is not a fluke, many Tele Vue scopes are doublet APOs also.
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