IDAS Filter System

I just prepared for IDAS imaging system for my own use. Probably this double-stacking system will be my default for a while, regardless of one or two filters.


Personally I’m still quite comfortable for using a consumer camera for 1st trial purpose. So I just setup with a modified SONY A7 first. I will try to use ZWO camera later. Thanks for the short flange back mirrorless camera, which allows me to set two filter boxes in-between. Adding 1mm spacer, the light path turns perfect after two filter’s refractive correction with my no-filter A7.


With BORG 72FL F4 (prototype)

Clockwise from upper right, NGS-1, NB1, ODW(clear) and NB2. What I can do with these filters are;

  • ODW + NGS1 : broadband color under the light polluted sky
  • NB2* + NGS1 : dual-band color (Ha and OIII)
  • NB3*(when comes in) + NGS1 : dual-band color (SII and OIII)
  • ODW + NB1 :  tri-band color (Ha, OIII and Hb)
  1. *NB2/3 must be set in at the objective side.
  2. NB1 performs alone. ODW is just in for the par-focal. All are 52mm sizes. So large enough for full frame sensor.
  3. NGS1 and NB1 may be replaced with others like LPS-D2 or conventional UV/IR blocking filters. I have just picked NGS1 since it seems to be suitable for my backyard sky.

These Marumi filter case allows to set a filter holder itself. Very convenient. Probably now I need to label on each case, or I’m sure I set a wrong filter at the dark site.

Now ready to go. I’m excited about that!





~ by tedishikawa on June 13, 2019.

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