Quote:
Originally Posted by Peter Ward
Well.... 
I'd disagree. Sony don't publish absolute QE data, and it seems derived values vary a tad depending on who's website you want to believe.
So does Christian Buil...
....his testing indicates it's more like 20% at best.
http://www.astrosurf.com/buil/isis/noise/result.htm |
I've used both sensors extensively and also notice exposure times on this site. Its at least 30%. That link simply goes to an ad for his publications. I thought he measured DSLRs mainly. I am not sure what equipment you need to measure QE but he is not a professional and I doubt he has the gear to do it with properly.
And its more like 40% - 50% plus more sensitive in narrowband where its even more sensitive in O111 than the venerable 6303 sensor. 66% QE in O111 is unique. 70% in Ha is also unique. You can get a pretty clean 10 minute Ha sub from this sensor. What is the KAF8300's QE in Ha or O111? At a guess 45% and 25% versus 70% and 66%
My experience is the KAF8300 is a very poor match for focal lengths greater than around 2 metres. The Sony is not bad, not quite 9 micron performance but it does allow genuine 2x2 binning which takes it to another level with only a modest drop in resolution. The higher QE and low read noise seems to make up for the mismatch in pixel size and focal length to a large degree.
But there is a reason the KAF8300 is the most popular sensor, its quite versatile and suits your average astrophotographers telescopes and imaging conditions quite well, its got a reasonable FOV without too demanding of the optics so its a good fit for most.
Greg.