RE: [APML] February Images and Other Stuff

["Jon Kolb" <jkolb@datawest.net>]

Andreas, Bobby, Mike C., Chris C., Jim, Warren,

Thanks very much for you kind words!

Matt, Tony, Maurice, Chris S., Jim, Mike&D,

Answers to your specific questions appear below.

> Some truly spectacular imaging... I really like the one showing the
link between the HH > and M42 and Bernard's Loop... awesome.

Thanks, Tony!  I couldn't believe how much was on the slides when I
started working on them.  This actually makes the image difficult to
process, since you have to decide how much of the faint stuff to show
without making it look foggy.

> Where is Badger Flat? 

Badger Flats is a square mile of state trust land just off of US Hwy. 24
about 3 miles E. of Wilkerson Pass, and is about 50 miles W. of Colorado
Springs.  Any decent road atlas should indicate this pass.  It's a good
site for one-night outings, since I can be there in an hour, and it's
only an hour back if the weather goes bad.  The site itself is open
meadow at 9000 feet with some Ponderosa, but it's bordered on all sides
by the Pike National Forest, and there are several other good sites with
tree cover nearby if the wind pipes up.  The Colorado Springs
Astronomical Society has their annual Rocky Mountain Star Stare at a
site nearby.  

> The stacking of E200 and 400F seems to work well.

Yes, Matt, this combination looks like a winner.  I like it better than
the SHQ100+RG200 hypered combo I used last Fall, and both films are
available in 120 size.  Both films seem to have outstanding reciprocity
characteristics and fine grain.
 
> The Central Orion shot is fabulous, but the background is a bit dark.

Compared to the other shots, the background does seem dark, but it's
also in a much less crowded part of the sky.  Like I mentioned to Tony
above, it's a challenge to find a pleasing balance between showing faint
nebulosity and losing detail by bringing up all of the faint stuff on
the slides. 
 
> I notice some dark circles around almost all the stars 
> embedded in nebulosity in the IC405/410 and IC443 images.  I 
> think they significantly detract from the shots.  The easiest 
> remedy is to exclude those stars from the mask (i.e. only 
> shaping the field stars not embedded in the nebulae).

It's much less objectionable in the 405/410 image, since I didn't use
any star shrinking technique on that one - the effect you noticed is
probably due to unsharp masking in that image.  IC443 is another animal
though, and I agree that the black eyes really detract from the
nebulosity.  I just didn't think to draw a curve around the nebulae and
remove those stars from the mask, but I'll try it again and see what
happens.  BTW, I think a small amount of this effect gives sort of a 3D
look, but it sure looks bad when overdone.

> Do you observe and photograph completely alone or is your wife joining
you? Aren't you 
> afraid of bears or don't they live in or near your observing sites?
I've recently seen 
> the movie "The Edge" starring Anthony Hopkins and Alec Baldwin,
therefore my question.

Hi, Maurice.  My wife likes to go camping, but not this time of year!  I
believe the bear you are referring to in that film was an Alaskan Brown
(aka. Grizzly), an enormous and potentially very dangerous animal
indeed.  Thankfully, we only have the much smaller Black Bear here in
Colorado, but they can still reach up to 150 kg. in size, perhaps larger
in the western part of the state.  Although the sites I use are all
known bear habitat, they're all asleep right now!  Most animals will
avoid humans, but in hard times the bears and mountain lions (Cougars)
can and do attack.  We had a late freeze last Spring that killed off a
major food source for bears, and there were a couple dozen attacks last
Summer because of that.  I fear the mountain lions much more than the
bears, since they are absolutely silent, and because I've found tracks
right outside our tent in the past.  I carry some "bear medicine" that
also cures lions, but that's probably off-topic.

> Im presuming you use the provia for the blue part of the response
because of the 
> extreme reds of the E200?

That was the idea, Chris, but it's really surprising how much blue the
E200 will pick up if you expose long enough - especially if it's pinkish
blue you're after, like that around AE Aurigae.  The 120 format E200
seems to be slightly better at this than the 135, but it could also be
differences in the transmission characteristics of the Borg vs. the
Epsilon.  Nevertheless, the Provia films are indeed much more responsive
to blue than E200.  I think the combination works very well.

> I like your home made mounting plate. It looks like it's based on the
Losmandy side by 
> side plate?

Hi, Jim.  The plate can be used on either the primary G-11 saddle or the
DSBS, just like any other Losmandy plate.  In fact, it uses a Losmandy
DP13.5 doveplate to interface with the saddle.  If you have one of these
made, be sure to get a nice, rough sandblast finish - it really grips
things and you can mount big cameras like the Pentax 67 with just one
screw in the tripod socket.

> The Borg looks like a very fine instrument. ( have you put the TAK
away for a while ? )

No Mike, the Epsilon did some work this month after being out of
collimation in January.  Unfortunately, the composite California nebula
I shot was poorly composed.  I did get a wimpy M101 shot with it, but I
haven't tried to process it yet.  The Epsilon was also used on my
attempt at Gum15/17, but the seeing wasn't good enough that low to make
processing the image worthwhile.  It's going with me to AZ in April if I
can make it down there.

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




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