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gary
04-11-2007, 05:01 PM
Firstly, a disclaimer. The following post relates to a product of Obsession
Telescopes. Obsession are a customer of Wildcard Innovations and buy our
Argo Navis Digital Telescope Computer.

Dave Kriege will be a name well known to many of you. Dave is owner
of Obsession Telescopes (http://www.obsessiontelescopes.com) and co-author of "The Dobsonian Telescope (http://www.willbell.com/tm/dobtel.htm)",
a book many regard as the bible of large truss pole telescope design.

Earlier this year, Dave generated quite a lot of excitement when he announced
he would be introducing a new telescope to the Obsession range. He kept the
lid on what the scope would look like, so many of us were anxious to see it
when he brought the pre-production prototype to the Texas Star Party (TSP) in
May this year.

In the early morning hours of my first night at TSP, I was able to track Dave
down on the observing field. "Come and take a look at this", he whispered to
me. Opening up a modest size box, I was stunned to see inside a complete
18" aperture truss pole Dobsonian telescope in its 'knocked-down' state. It was so
compact, it was evident it would fit into the boot of just about any car.

The next day, to a packed meeting hall, Dave introduced the new 18" f'4.2 UC
(Ultra Compact). When he assembled the scope in under three minutes
there was an enormous ovation.

Whist at TSP, I had a brief opportunity to use the scope and was convinced
straight away that Dave had made no compromises when it came to the
performance of the instrument.

Therefore when Dave brought a production version of the 18 UC to Australia
last month, I was excited about the prospect of getting to use it again, this
time under dark Australian skies near Coonabarbran for a week.

In the back of my Subaru Forester, I had transported up one of Andrew Murrell's
scopes, a classic 18" f/4.5 Obsession fitted with Argo Navis and ServoCAT.
The classic f/4.5 18 fits into a car like the Forester if you fold the back seats
down, but it takes up a lot of space and I avoid lifting the mirror and rocker box
on my own. The optical and mechanical performance of the classic 18 is
par excellence and anyone who has ever used an Obsession instantly
understands what premium telescopes these are.

Dave assembled the f/4.2 18 UC a few meters away from the classic f/4.5 18
I was using, so it was convenient to go back and forth between the two scopes
to make comparisons.

What was instantly evident was that the new 18 UC was delivering exactly the
same quality views as the classic 18. That comes as no surprise as both scopes
have the same quality 2" thick mirrors that come from a choice of Galaxy or OMI,
supported by 18 point mirror cells and coupled with high quality secondary
mirrors along with refinements such as Feathertouch focusers.

Dave had also brought with him a couple of new TeleVue 13mm Ethos
eyepieces, which I had also first used at TSP whilst we spent an night observing
with Al Nagler. These were wonderful 'cruising' eyepieces for the 18" scopes
and the views of the Tarantula were probably the most stunning I had ever seen.

To see how the new 18 UC would fit into the Forester, I folded the back seats up
and the virtual mirror box when placed inside the rocker fits in easily. In fact,
the scope is likely to fit into the boot of just about any car. The virtual mirror
box and rocker measure 61cm x 61cm x 34.3cm high. The only other component
was the clever inter-connected 6 pole truss which slid into a cardboard
tube for transport. These were longer than the Forester's boot, but easily
fitted between a couple of passengers in the rear seat or optionally on the
roof rack. The good news is that the heaviest component of the scope to lift
was the 28kg virtual mirror box and mirror. Since this particular component is
so compact and therefore not awkward, this is something I could lift on my
own if taking care. The eyepiece height at the zenith is 180cm, so a vertically
challenged individual such as myself only requires a very short step ladder
which again is not a problem to transport in the boot of just about any car.

The bottom line - here is a reflector with 18 inches of high quality optical
performance and fabulous mechanical performance that will fit into the
boot of just about any car and which can be lifted out of the car and assembled
in just a few minutes by the average bloke on his own.

In this post and some posts below, I have attached some photos I took
showing the 18 UC in the back of the Forester and Dave lifting it out.
One image also shows the telescope in an optional Air Transport Association
(ATA) compliant travel case. I have also attached some photos showing the scope
in various stages of assembly. In the background can be seen a couple
of other Obsessions, a 25" and a classic 18.

Dave tells me the 18 UC is now in production. He and some American
observing colleagues who had also flown out for the week were audibly
gasping as they cruised the regions in and around the SMC and LMC.
When we Aussies hosting them looked through the same 18 UC fitted
with Ethos, we started making the same noises, despite the fact these
were familiar skies to us.

Best Regards

Gary Kopff
Mt, Kuring-Gai

gary
04-11-2007, 05:04 PM
Here are some additional images showing the Obsession 18 UC being
assembled and finally assembled. These images were all taken by myself at
Coonabarabran October 2007.

The last image shows Dave Kriege (right) and myself (left) standing behind the
scope with its shroud on.

Best Regards

Gary Kopff
Mt. Kuring-Gai

Stephen65
04-11-2007, 08:34 PM
I have a Forester, now I just need that scope.

norm
04-11-2007, 09:12 PM
Great write-up Gary.

Certainly can see a niche for this type of scope. Was there any noticable coma being f4.2 and how was it for collimation?

Cheers, Norm

gary
04-11-2007, 09:20 PM
Hi Norm,

Dave recommends a Paracorr at this short a focal length.

Apparently the collimation is just as easy to do on the UC as it is on the classic.
Obsession ship the mirrors with a center mark to assist. Optically, it was brilliant.

Best Regards

Gary Kopff
Mt. Kuring-Gai

gary
04-11-2007, 09:35 PM
Hi Stephen,

It certainly looked sweet in the back of mine. :)

As I mentioned, you can fit it easily into the back cargo area with the rear seats
still available for passengers. You get a lot of aperture for the number of
cubic cm the UC occupies when in its compact transportation state.

I suspect there are a lot of enthusiasts out there that would love to buy that
telescope they always wanted but aren't in a hurry to buy a new vehicle to
transport it in. You don't need a station wagon or trailer for this thing, just
about any car will do, even most small ones.

For some, this opens up the opportunity for observing to become a family
experience. With the rear seats free, there is space for the kids.

Best Regards

Gary Kopff

coldspace
04-11-2007, 10:28 PM
Hi Gary,

Any idea on pricing for this beauty.

Matt

gary
04-11-2007, 11:53 PM
Hi Matt,

Apparently they are priced the same as the classic 18" with the same items.
Obsession have some US Dollar pricing on their web site here -
http://www.obsessiontelescopes.com/telescopes/18_UC/index.html

Best Regards

Gary Kopff
Mt. Kuring-Gai

fringe_dweller
05-11-2007, 04:54 PM
wow nice Gary! also love the extremely photogenic location and weather! :eyepop: and great photos, drooool! cheers!

Roger Davis
07-11-2007, 11:19 AM
Geez Gary, Do you know how many owners of Foresters there are in my club alone? Let me think, gee just in the Instrument Making Section there are four of us! and that's a group of about 20. Extrapolating that's 180 members with Foresters! What has Dave done??! Looks like I'm having words with him!!

gary
07-11-2007, 11:33 AM
Hi Fringe_dweller,

Thank you! I appreciate your kind comments.

Best regards

Gary

gary
07-11-2007, 11:56 AM
Hi Rog,

Love the extrapolation! :)

I bet we all did the same thing. You are down at the Subaru dealership
(there's an astronomical connection right away of course, with Subaru being
the Japanese name for The Pleiades), you open up the hatch at the back
and the first thing that enters your head is imagining a telescope of some
sort being in there. :)

I even had a US enthusiast email me yesterday, having read this thread on
IceInSpace, asking my opinion of the Forester as an astro-transportation
vehicle. (Hello Mark!).

With light, sweet crude heading toward US$100 a barrel, I am sure down-sizing
of vehicles is a consideration for an increasing number of Americans. DaveK,
being the astute businessman he is, has undoubtedly seen this coming, so the
Ultra Compact is very much a product introduction with impecable timing.

Best Regards

Gary

Blue Skies
07-11-2007, 06:40 PM
This new ultralight model has certainly got me salivating. I don't have a subaru but I was certainly thinking big scopes when I got my early model Honda CR-V with heaps of room in the back! A friend here bought a 15" Obsession a year or so ago and I finally got to look through it recently under dark skies and was very impressed - it was outdoing the club 17.5" with Coulter mirror that has a damaged surface. The compact size is definitely a drawcard, as well as it being transported in only two 'packages', that makes less to forget when packing the car.

gary
08-11-2007, 07:38 PM
Hi Blue Skies,

You might like to request a copy of the latest Obsession DVD. I received
a copy today from Dave Kriege and it includes a new segment on the 18
Ultra Compact that was video'd at Coonabarabran. You get to see Dave
assemble and disassemble the scope and he talks about its various attributes.

The DVD is free and Dave will post it to anywhere in the world for free as well.
See here for details - http://www.obsessiontelescopes.com/contact/index.html

Best Regards

Gary Kopff
Mt. Kuring-Gai

Omaroo
08-11-2007, 09:34 PM
One word - "beautiful"

GrahamL
09-11-2007, 10:20 AM
very nice gary.. any noticable bump when the alt bearing moves
over the folding joint ?

gary
10-11-2007, 02:18 PM
Hi Graham,

Thanks for the post.

Dave is proud of the fact that he came up with a clever way to eliminate the bump
completely, so there is no bump.

Best Regards

Gary Kopff
Mt. Kuring-Gai

tnott
11-11-2007, 01:40 PM
Looks great. Similar ideas to many of the newer ATM scopes out there at the moment. I'm interested that he managed to eliminate the bump where the bearing folds over. In the Tridob design I copied for my 16" scope this is accomplished by having three fins, with the front two folding over the mirror box, but it requires extra bits of teflon as keepers on the sides. http://www.iceinspace.com.au/index.php?id=63,324,0,0,1,0


Can't see the point of the shroud to be honest, as most stray light gets in around the top end around the focuser and secondary assembly, and this is above the shroud in this design. Also, light is not blocked from getting into the light path around the primary either. Might be more to do with customer perceptions than blocking stray light. personally, I'd be baffling the focuser and using a bigger baffle behind the secondary instead.

Tim.

janoskiss
11-11-2007, 01:59 PM
Main reason to have one, and it's a good one, is to help keep dew off the primary.

tnott
11-11-2007, 02:09 PM
Haven't ever heard of this happening to a thick 18" primary. My 16'' has never, ever dewed up. In fact I am pretty sure that cooling that much thermal mass is more of a problem. Michele Plettstone maintains that a shroud makes little or no difference with dew formation.

But it would keep keys or coke off the primary. :lol:

Blue Skies
11-11-2007, 03:25 PM
It happens!! The 17.5" Coulter mirror I mentioned above sits in a classical type mirror box with no shroud around the trusses and it dewed up two nights running around 2-3am in then morning only a month ago in October. I've seen plenty of dewed secondary mirrors but this was the first time I had seen this scope dew up like that, and it wasn't even a particularly cold and dewy night.

gary
12-11-2007, 12:34 PM
The Obsession video of the 18" Ultra Compact is now available online.

You can view it on YouTube here - http://youtube.com/ObsessionTelescopes
or you can view it in Quicktime format from the Obsession web site -
http://www.obsessiontelescopes.com/telescopes/18_UC/index.html

You can see the scope being assembled and disassembled whilst Dave Kriege
provides a commentary.

The video was shot at Coonababrabran in New South Wales not far from
the Anglo Australian Telescope at Siding Springs, in early October 2007.

At one point, I make a brief cameo. :)

Best Regards

Gary Kopff
Mt. Kuring-Gai

gary
12-11-2007, 01:51 PM
Hi Tim,

The scope comes with Kydex light baffles both for the secondary and the
primary, it is just that they were not installed during the daytime when I took the
photographs. You can see the light baffles in the attached photograph taken
by an 18 UC owner at the recent Okie Tex.

In keeping with the fast setup time, both baffles attach in just seconds.
By keeping the primary baffle removed until one starts observing, this may
also assist with the mirror cooling down to ambient much more quickly.

Best Regards

Gary Kopff
Wildcard Innovations Pty. Ltd.

Blue Skies
12-11-2007, 05:10 PM
Thanks for that, gary. I went and watched both videos, interesting viewing. It made the counterweight system more understandable and gives a good idea of the size of it. I loved the sound effects - flies, wind and magpies. How Auatralian is that! But at one point the winds gusted up a bit and even with the shroud on it didn't blow about much, which was encouraging. It can get pretty windy at night over here in the west in summer if an easterly kicks in.

gary
12-11-2007, 07:06 PM
Hi Blue Skies,

As Dave demonstrated when we were in Texas, the neat thing about the
counterweights is that they open up and you can add or remove sand or
shot to get the balance 'just right'. This is handy if you are adding or removing
something heavy like a 31mm Nagler.

The flies really were something else at Coonabarabran, but we told our
visiting American colleagues they were in honour of that great overlooked
southern constellation, Musca.

The bird calls at sunrise up this location are iconically Australian as well.

As you noted, it was quite gusty whilst filming, but the scope does not sail
around.

Best Regards

Gary Kopff
Mt. Kuring-Gai

mrsnipey
14-11-2007, 11:51 AM
The UC looks amazing! So simple and clean cut. I'm glad I didn't get one of the Standard Obsessions.

I must say that he's a bit rougher with his telescope than I am with mine. I cringed a couple of times when he got near the primary and he just chucked the secondary on the ground. It can obviously take the battering but I could never imagine treating mine that way. I love my telescope.

Having said that it looks very impressive. I love the fact that the secondary attachment is so thin. I don't like the large wooden ones. I guess the metal gives it a bit more rigidity. And I like how the Telrad just swings into place.

Gary, how do the encoders attach to the virtual rocker box for your Argo Navis?


Thumbs up from me. :thumbsup:

tims
19-11-2007, 03:06 PM
Hi all

The Obsession website has the cost of all their telescopes but wondered if anyone can advise what they charge for the shipping and freight costs to Australia for the Obsession 18 UC and again for the standard (full size) Obsession 18.

thanks

Tim

coldspace
19-11-2007, 04:13 PM
Hi Tim,

Go to the obssesion web site and you can E-mail Dave all your enquiries and he responds back to you in 24hrs with pricing. I was told about $1500 US$ last week to get the UC18 air freighted over including insurance.

Regards Matt.

Satchmo
19-11-2007, 04:53 PM
Don't forget about $500 broker/ port charges on this end plus 10% GST on the total of purchase price + freight.

Mark

erick
20-11-2007, 04:58 PM
Thanks for the tip, Gary. I received my copy together with various paperwork, posters and price list etc. The one I received didn't have the UC footage on it, but I've seen the YouTube video. No UC mention in the paperwork as well. No problem - there is plenty on the website.

Quite neat to watch the "home video" style. Nothing hidden here, no slick sales pitch. Just a detailed demonstration of the construction, assembly and mechanicals - plus ServoCAT and Argo Navis description/demos.

I'm particularly impressed that Sheryl Johnson can collimate her 20" with the primary mirror cover still in place, but maybe I'm missing something here :confuse3:

gary
20-11-2007, 05:21 PM
Hi Eric,

Great to hear you got the information pack. As mentioned, I did receive one
of the newer DVD's that includes the 18 UC but it was good you were able
to watch it on YouTube.



Dave likes it that way. Just raw. I think he pre-dates a style now made popular
with reality television. He doesn't even tell you he will film you. He just pulls
out a camera and says "start talking" ! :)

By the way, if you have never picked up a copy of the book he co-authored
with Richard Berry, "The Dobsonian Telescope", it makes an excellent read
and a fabulous reference.



So use to it, she can probably collimate with her eyes closed. ;)

Best Regards

Gary

gary
20-11-2007, 05:33 PM
Dave Kriege reports that the 18" Ultra Compact has made the much
coveted U.S. Sky & Telescope 2008 Hot Product list and will appear in the
January issue.

The Tele Vue Ethos 13mm eyepiece is also believed to have made the list.

Having had Argo Navis chosen a few years ago as one of the U.S. Sky & Telescope
Hot Products of the Year, I can tell you how good it feels to be awarded this
honor. This is the astronomical industry equivalent of the Academy Awards.

Congratulations to Obsession and Tele Vue.

Best Regards

Gary Kopff
Managing Director
Wildcard Innovations Pty. Ltd.
20 Kilmory Place, Mount Kuring-Gai
NSW. 2080. Australia
Phone +61-2-9457-9049
Fax +61-2-9457-9593
sales@wildcard-innovations.com.au
http://www.wildcard-innovations.com.au

prova
20-11-2007, 10:55 PM
apologize if this has been mentioned, but will their be an Aussie dealer for these at some point?

g__day
21-11-2007, 09:00 PM
I was at BinTel the other day and mentioned to Don the Skywatcher look great - but they just aren't an Obsession - having viewed Zane's 24" Obsession with the Argo Navis and Servo cat.

Don mentioned oh yeah (at some length) and had alot of great things to say about about Zane and Magellan, then went on to rave about Argo Navis - saying it should be the product of the year - thought you'd like to hear that Gary (and Zane)!

gary
21-11-2007, 11:41 PM
Hi Prova,

Customers are just ordering Obsessions direct from the U.S where they will also
customize them with whatever options you request. They even come with
a brass plate with your name on it.

Sea freight is another option that Dave can undoubtedly quote on. This
method of freight is particularly attractive for the classic range of Obsessions
which are somewhat physically larger.


Best regards

Gary Kopff
Mt. Kuring-Gai

gary
21-11-2007, 11:55 PM
Thanks g__day,

It is always nice to receive a compliment first hand, but to hear it second-hand
can be even nicer, so we appreciate you passing that on.

Mai and I are very fond of Don and his contributions to amateur astronomy
and his knowledge of telescopes and astronomy is something we deeply admire.

Best regards

Gary Kopff
Mt. Kuring-Gai

g__day
24-11-2007, 11:32 AM
Gary,

Having seen your gear at Magellan used in competent hands (I did a review on this earlier this year - a tale of two observatories) it worked so ridiculously well, the compliments are simply well earned.

Matthew

tnott
06-12-2007, 09:44 PM
Hmmm. Let's see - it is a very rigid design, with 2mm thick steel-vaned spider. The diffraction spikes would be more obvious than the wire spider on my current scope but the setup has other practical advantages. The poles, themselves connected at the apices for greater structural strength, are connected to where the spider vanes meet at the top and then bolted directly to the sides of the mirror cell at the bottom. It would work well scaled up to a larger size and hold collimation really well like the original version of this design - Greg Babcock's scope from a few years ago ( http://www.synrgistic.com/astro/24inch.htm ).

I think I might build a 22" F3.66 version - feet on the ground for most viewing, almost double the light collection of my 16" Tridob and in as lightweight and compact package as possible.





Think I'm joking don't you......

Tim

erick
06-12-2007, 10:14 PM
Nope! I'm looking forward to joining the queue at a star party for a look! Sounds good to me. :thumbsup: