Last night I had somewhat better seeing than the night before so my tests of
the new IMG1024S Dream Machine continued but with somewhat better results.
I ended up concentrating on the "tadpoles" in IC410, continuing on an object
that I had taken a few test exposures of the prior night.
I used the very nice "suburban friendly" Custom Scientific 3nm FWHM Halpha
filter to take seven exposures of a half hour each. I can say with zero
hesitation that the 3nm Custom Scientific Ha filter is the best Halpha
filter I have ever used. My comparison set so far consists of the set of 3nm
Cs, 4.5nm CS, 6nm AD, 9nm pre-AD Schuler. I still haven't yet tested the new
7nm Baader but am excited to see a nice $300 solution for 50mm that, based
on the work of others, appears to work every bit as well as the higher
priced 6nm filters that seem to be so popular, but at less than half the
price!
The seeing still was not all that great due to upper air disturbances caused
by the position of the jet stream, but was definitely better than Wed night.
Hopefully I will have good seeing soon, because I would like to shoot the
scope at full focal length, without the reducer (5760mm vs 3366mm), to
continue my testing.
The Dream Machine's big 24 x 24 micron back-illuminated pixels are like a
photon vacuum cleaner compared to the "ccd with sunglasses" performance I
see with the KAF3200ME sensor. Not a bad sensor at all, mind you, but it is
in a different league with the 6.8 x 6.8 micron microlensed pixels. When the
seeing is good, then it is a lot of fun to use on the stinger at 0.42
arc-sec/pixel.
The DM used with the reducer gives me 1.42 arc-sec/pixel and without it is
0.86 ASP.
I processed the image two ways: with and without deconvolution.
In this case due to the decent s/n I get from the big pixels exposed through
a 3nm filter at f/7.1 I can tolerate some deconvolution without mucking up
the image. It is a pleasure to have so much signal after operating in
starvation mode for the past month taking the data for Jones 1.
http://www.narrowbandimaging.com/ic4...ch_ha_page.htm
comments welcome.