Quote:
Originally Posted by xelasnave
 Thanks JA as with everything it just keeps getting better.
I had estimated 5.67 times faster but I approximate a great deal and then subtract 7% just for pillow calculations but I usually get rather close.
It will be interesting to see just how far I can push things...2seconds at 350 gain and 2000 saved subs stacked at 3 times drizzle 
Alex |
Alex,
It
was 7.43 times faster based on the increase in light collection area of the RASA 11 compared with the 115mm f/5.5 AND the increase in Quantum efficiency changing cameras from the ZWO ASI1600mm (60%QE) to the ZWO ASI2600mm (91%QE !!!) which is a great result,
but I may have mentioned that the sensors are a different size and wanted to account for that, which will drive the improvement even further to over approx
10* times better light collection I'd say.
*I lost my post in the ether somehow/timed out so I will come back with and edit with more exact detail soon.
EDIT: Further to the above, and trying now to correct the estimated improvement created by the sensor increase in size (yes I know the FOV will be different), the sensor area of the ZWO ASI2600mm is 1.56 times that of the ZWO ASI1600mm so that it (the ZWO ASI2600mm) will intercept more of the light collected by the optics (think of it as
less of an internal restriction/aperture/field stop in a conventional camera, i.e: akin to a lower f/number in photographic terms).
Taking this in to account you could expect something like 7.43 x 1.56 = ~11.6 times, call it 12 times more light collected by the RASA 11 f/2.2-ZWO ASI2600mm system compared with the 115mm f/5.5 Scope-ZWO ASI1600mm based system.
So in light gathering terms:
what previously was a 60 second exposure is now more like 5 seconds.
Best
JA