Return of the Denkmeier

Hi Gang:

As some of you may remember, I had the opportunity to test the 2"
Denkmeier Binoviewer some time back. I was suitably impressed, but due
to the weather we were experiencing down here on the Gulf Coast at the
time, my opportunities to use the Denk on a variety of objects were
somewhat limited. Sure, Saturn looked great, the Moon looked great,
M42 looked great, but that was just about the extent of it.

Recently, the good folk at Denkmeier Optical
http://deepskybinoviewer.com/ asked if I'd like to borrow one of
their demo units for some further testing. Since my initial experience
with the Denk had been positive and had frankly made me something of a
binoviewing convert, I couldn't help but say "yes."

By way of background, before I had the chance to test the 2"
Denkmeier, I was not a real fan of binoviewers in general. I had never
had much success using them. I couldn't _ever_ seem to completely
merge images, and the resulting strain and headaches meant I avoided
them like the plague. You can read the full story in my review "How I
Learned to Stop Worrying and Love Binoviewers" available he
http://skywatch.brainiac.com/sw030403.pdf, but to make a long story
short, I found it _easy_ to merge images with the Denkmeier, and the
entire viewing experience was comfortable and rewarding.

In fact, the only criticism I had of the unit was the friction-fit
eyepiece holders. None of my eyepieces ever dropped to the ground, and
the eyepieces would stay put when I slid them in and out for diopter
adjustments, but I just felt they weren't as secure as they could have
been, and that the O-ring arrangement that applied tension detracted
from the appearance and overall build-quality of an otherwise
outstanding piece of gear. I had been told that in the interim that
both the "Premium" Denkmeier II (2") and Standard Denkmeiers had gone
to twist-to-lock self centering eyepiece holders, and I was anxious to
see how these worked.

In due course the "new" Denk arrived here at Chaos Manor South. The
binoviewer in question, the 1.25" unit, was, as the previous
binoviewer, contained in a black plastic case of sporting goods
heritage. What I received this time was basically Denkmeier's
"Standard SCT" package. In addition to the binoviwer itself, also
included were the 2" Starsweeper, a 2x "multiplier" lens and requisite
adapters. The eyepiece holders, as I had suspected, were a major
improvement. Smoothly threaded, they held the eyepieces securely and
were easy to use and attractive.

On to the Chiefland Star Party. For those of you who've never attended
this event, you should, the skies are DARK and the temperatures were
nice and warm (this year, anyway). The trip to this star party is a
reasonably easy one for me, about 6 hours from Mobile to Chiefland,
which is roughly 65 miles North of Gainesville in the Florida
interior. I had done some limited viewing with the new Denk at the
Deep South Regional Star Gaze in October, but the fact that I only
had one good night meant that I used the Denk less than I probably
should have.

At any rate, my astro-buddy, Pat Rochford, and I hit Chiefland just
right. It looked like we'd be favored with two excellent nights, and
we were. I spent the first night working my observing list and using
the StarSweeper for single eyepiece viewing. As I reported last time
around, I'm impressed with this gadget with or without a binoviewer.
It provided a decent-looking field edge with most eyepieces, and I
really didn't miss the f/6.3 reducer/corrector. This is far better
than the f/5 reducers we used in the bad old days. An advantage of the
StarSweeper, as before, was that it allowed me to use the big back of
my C11 via an EyeOpener, something you can't do easily if you want to
use a Meade/Celestron r/c.

I did break-out the Denk for Saturn on this first night (Friday), and,
once the planet had risen to about 40 degrees of altitude, it was
amazing. Using 2 TeleVue 8mm Plossls, I was just blown away. The color
variation across the ring system, from the dusky reddish of the Crepe
Ring, to dirty yellows and snowy whites, was amazing. The disk itself
was highly detailed, with the banding beginning to take on the detail
you see in Jupiter's belts rather than the usual pastel smudge you can
make out on Saturn. I didn't trust intuition, but switched back and
forth between binoviewer and single eyepiece to check myself. Yes, as
I don't think many folks will dispute, you CAN see more with a
binoviewer, with THIS binoviewer, anyway, on the planets than with a
single eyepiece, no matter how good that single eyepiece (Naglers and
Panoptics in my case).

Enough single eyepiece deep sky viewing! I declared Saturday night at
Chiefland to be a "binoviewing night," and my scope a
"single-eyepiece-free zone." :-) One thing I should mention is that
using the 1.25" version of the Denk was not a huge hassle. Yes, the II
_is_ nice and has some advantages beyond a 2" barrel including
superior coatings and tighter optical tolerances. However, when it
comes to using the "Standard" in a 2" diagonal with 2" accessories, I
found that attaching a good 1.25"/2" adapter, my
compression-ring-equipped Intes, worked very well indeed. The Intes,
like most 2" adapters these days, is threaded for 2" accessories, so
with it firmly in place, I stopped missing the Denkmeier II's 2"
barrel fairly quickly.

I suppose the most memorable view I had on this evening was NOT M42,
though I did take a look at it once it cleared the horizon. No, the
hit was M33. With a pair of 25mm TV Plossls in the Denk and the
StarSweeper screwed-on, it was perfectly framed. Big enough to show
plenty of detail, but enough dark field around it to provide good
contrast. The first thing I noticed was how _easy_the spiral structure
was. Sure, I've looked at many photos of this amazing object (and
taken a few myself) over the years, but I wasn't being fooled into
thinking I saw something I didn't. The Pinwheel shape was _prominent_.
Now, this was a good night, a very good night, so to evaluate the job
the Denk was doing, I switched to a 22 Panoptic, a single eyepiece,
and, yes, the spiral structure was just less evident. Back to the
Denk. This galaxy's huge HII regions were picked off one after
another, but the real treat was the tiny nucleus of M33 twinkling in
and out.

Of course there's always the question of brightness when using a
binoviewer on the deep sky. There is no doubt that a binoviewer
decreses the amount of light reaching each eyepiece. How obvious and
serious is this? With the Denk, it was really _not_ a handicap. Yes,
when you go back to single eyepiece viewing you can detect an increase
in image brightness. But not as much as you might have expected. I
don't know whether this is due to the Denk's construction, the fact
that things are easier to view with both eyes, or, probably, both of
these factors. At any rate, the increase in detail that I noted with
the binoviewer was well worth the small brightness penalty.

Did this decrease in brightness make some objects "out of bounds" for
the Denkmeier? No. Not for me, anyway. If you're a real galaxy
fanatic, things may be different for you, but I found that any galaxy
I wanted to view was in range of the Denkmeier. I took particular care
to check this, and looked at a variety of smaller galaxies in the 11.5
- 12 magnitude range. All were as visible in the binoviewer as with a
single eyepiece. Dimmer than 12? I certainly don't push too much
dimmer with a C11 (hey, I'm really a Lunar/Planetary guy these days!),
and I suspect that most galaxy hunters are using scopes in the 20 inch
plus aperture range. Meaning there's more light available for the
binoviewer.

The thing was, I had just as much fun with the Denkmeier on the deep
sky as I'd had with it on the Solar System. And you can sure "wow"
people with it. Being a recent convert to the binoviewing "religion,"
naturally I wanted to proselytize, but I didn't have to. The fact that
I had the only Denkmeier on the field (as far as I know/knew) meant I
had a stream of visitors wanting to check it out. Maybe initially on
Saturn, but one look at M42 peppered with "3D stars" and I had plenty
of converts.

There were, by the way, several other brands of binoviewers on the
field, so I had the opportunity to compare their performance to that
of the Standard Denkmeier, if not in side-by-side fashion. My opinion?
For ME the Denkmeier worked better and was more comfortable to use. I
do understand that "comfort" when using binoviewers is a subjective
thing, and that what suits one person might not suit another, but I
can only report what _I_ experienced, after all.

Did I say M33 was my fave? Actually, my most memorable observation at
Chiefland was _not_ M33. Oh, that was great, but the _greatest_ thing
was the Denkmeier showing me the "Running Man" Nebula, that complex of
reflection nebulosity including NGC 1973-5-7. In the past, I'd never
been sure I'd seen it. It's like the reflection nebula in the
Pleiades; it's very easy to ascribe what you see to scattered light.
But the Denk pulled-out the real deal. Not just around those bright
stars, but fanning off into space, showing surprising size and detail.

What a night! Wish you'd been there!

Peace,
Rod Mollise
Author of:_Choosing and Using a Schmidt Cassegrain Telescope_
http://members.aol.com/RMOLLISE/index.html