RE: [APML] RG200+SHQ100 Composite Posted

[Jon Kolb <jkolb@mindport.com>]

Thanks everyone for your comments and questions, both on- and off-list.
I've tried to respond to a few of these below:

> There is a distracting blur in the center portion.

This is the result of my attempt to smooth out the faint stuff by
selectively blurring it.  I obviously took this too far, since now I find it
distracting, too.  What I did was to use brightness masks that progressively
took in more of the bright nebulous areas, and process these areas
separately.  The idea was to try and create some dimensional depth between
the various parts of the nebulosity.  Finally, with almost all of the
nebulosity (and stars) masked out, I blurred everything else to smooth it
out - but instead it looks like it washed it out.

> I had no idea SHQ could be hypered so long and not skew the colour. 

That was in the first batch of hypered film I ever did, so I don't have much
to compare it with.  The PJ400 I did at the same time was way too hot for
the Epsilon - even 10 minutes on that stuff was very hot in the center of
the frame.  The SHQ, though, looks very smooth, with a little more green
than I would like, but easily compensated.  Perhaps the green can be reduced
somewhat by lowering the hypering time. I might try some of the hypered
PJ400 for meteor patrol. 

> Did you notice, that the edges are much sharper than the middle? I could
bet
> you did not use a pump and thatīs film movement, right?

I used the hand pump and hypered in the canisters.  I think the soft spots
you're referring to are the result of my smoothing technique described
above.  I can only pump down to just under -20 inmg, but since I'm at 6350
feet elevation, this should be very close to the recommended vacuum at sea
level for the hand pump.

> It almost has a tri-color look to it.  Interesting.

Well that's certainly encouraging!  Part of the reason for the progressive
masking referred to above was to acheive some semblance of 3D look that I've
greatly admired in Tony's and Chuck's work.  It'll never be the same as RGB,
though.  I also did just ever so slightly tweak the hue to be more pink than
orange. I picked only two pixels and dragged them just a tiny bit toward the
intersection of blue and red. The already strong blue response of both of
these films helps a lot.

> But someday we all gotta convert you to Photoshop! ;o)

I wouldn't rule that out.  So far, Sean's AV technique is the only thing I
haven't been able to duplicate in PW.  I'm going to try Jerry's technique
for the core of M42 this winter, and if that doesn't work out in PW, then I
might switch.  I've got to admit though, that PW is pretty darn powerful for
1/6 the cost of PS, and with a much, much simpler user interface.  I think
if it had come out before PS, the inertia might be opposite of what it is
today for astrophotography purposes.  Of course, PS offers some other things
I would like to have, but I'm not sure they are worth the extra cost.

Sincerely,
Jon Kolb
Adventures in Astrophotography
http://home.datawest.net/jkolb/
jkolb@mindport.com

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