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View Full Version here: : Your Focal Length Spread?


glend
04-08-2017, 02:28 PM
In another thread, PW set out his telescopes by focal length, covering a pretty wide range, and providing wide field to narrow field imaging. Here is what Peter shared:

"So in order of focal length my current ensemble is: FSQ85, FSQ106, AP130GTX, AP155, AP RH 305, Alluna RC16. They all bring something different." My apologies Peter if you din't want this mentioned here just let me know and i will delete it.

Just curious as to how others setup their equipment assets to achieve a range of focal length capabilities, and what drives the decision, other than a desire for a choice of field size and magnitude to suit?

Marke
04-08-2017, 02:49 PM
80 , 102 , 250 plus minus 0.67 focal reducer. Then look up object in either SkyX or CCDcalc and compare the projected fov with the object size and use what best fits.

Peter Ward
04-08-2017, 07:01 PM
:lol:...infamy!

Actually when I include camera lenses and barlows the range goes from 4.5mm to about 13.2 metres.... one has to be versatile :D