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nobody

05 Apr 2016 22:11



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Si cu filtrele, citeste mai atent manualele: 
For  brief  observing  sessions  using  refractors  with  less  than  80mm  of aperture when not using a tracking mount, it can be OK to use no energy rejection at all. Be alert for any rise in temperature of your telescope, diagonal, or Quark.

For  telescopes  under  approximately  150mm  of aperture,  a  screw  in  UV/IR  cut  filter  can  be employed  in  front  of the telescope diagonal. The  UV/IR  cut  filter  reflects  UV  and  IR  light back  out  the  front  of  the  telescope, reducing temperatures  inside.  Do  not  use  a  UV/IR  cut filter  with  a  telescope  with  an  integrated  rear field flattener or Petzval lens. The UV/IR cut filter must be the first optical element to encounter concentrated light.

For highest safety, a red or yellow glass front mount Energy Rejection Filter should  be used. This prevents almost all heat from entering the telescope.

To prevent damage, we recommend using an Energy Rejection Filter on telescopes of 80mm aperture or more, or when tracking the Sun for long periods. This can be a UV/IR cut filter mounted before the diagonal, or a full aperture red or yellow glass ERF mounted in front of the telescope.