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nobody

01 Mai 2017 10:30



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Telescope Optics, Rutten/Venrooij:
The ray-tracing results, presented in fig. 13.9, reveal that it is difficult to achieve a good performance with these systems. The reason for this is that three aberrations (spherical aberration, coma, and color) must be corrected simultaneously with a simple doublet. The axial color correction of the third system, the Jones-Bird, appears to be good, but the system exhibits both astigmatism and field curvature. Note that coma could be eliminated by separating the two lenses. Focal correctors of this type are sometimes mistakenly called Barlow lenses. This is incorrect because a Barlow lens does not change spherical aberration (see section 15.1); rather, a Barlow lens is designed for use in systems in which spherical aberration is already corrected.

Vezi ce zic si astia: No, don't throw it off any of the Manhattan bridges -- that's illegal.  Find a small bridge out in the country.  
Wouldn't give it away.  I couldn't do that to someone else.  Well, maybe my old boss, but even then. :lol:

Ca tentativa de colimare, poti incerca pe stea, daca ai norocul sa fie numai din oglinda primara.
Pentru laser trebuie sa dai jos corectorul.

La acel Erecting Eyepiece pomenit de 2SKY, poti folosi un ciocan mai mic. Nu glumesc.