Hofheim Instruments 8" f/4 travelscope

[Dragan]

Hi all,

Last summer I had the opportunity to purchase, what I believe to be, the ultimate travelscope. I bought it from German observer and fellow DSF member Marc Emde. We made the transaction over a weekend visit he had during a business trip to the states. I've had it out several times since July, including the Nebraska Star Party in August. Uwe Glahn, member and regular contributor here, also has experience with this very scope as he has had many opportunities to observe with it along side Marc - most recently being during a trip to Big Bend NP immediately after this years TSP. Uwe provided a fantastic sketch of Hickson 58 which he drew while observing with this very scope. His sketch can be found here.

At 8" f/4, its the largest aperture scope I know of that is capable of traveling with you as a carry on piece of luggage on the airlines. To make a long story short, the scope is nothing short of fantastic. So much so I wrote an article for Astronomy Technology Today magazine which can be found in this months issue. (Nov/Dec 2013) You can also read it here if you happen to not be a subscriber.

I have no relationship with Hofheim Instruments, though in full disclosure, I am trying my damnedest to get this scope easier and quicker to purchase here in the States. The scope makes an ideal travelscope and its 8" of aperture makes it a decent little performer on deepsky objects.

I just wanted to make the group aware of a great little product! I hope you're as impressed by it as I was the first time I saw it!

Thanks again Marc!

[svdwal]

There are a couple of other such scopes, some of them bigger too. In The Netherlands, ATM's make travel scopes based on the one designed by Pierre Strock: http://strock.pi.r2.3.14159.free.fr/Ast/Strock-250.html.

Here's one guy's website describing his home built telescopes: http://www.roelblog.nl/category/zelfbouw/. Some of them are directly based on the Strock, the latest one, a 350mm f/4 is a bit more radical. The website is in Dutch.

Here's another one, the smallest 8" travelscope in the world, apparently: http://www.astroforum.nl/showthread....hlight=Propdob. In Dutch too, check out the images by pressing the image links.

Then there's a commercial vendor, Sumerian Optics, http://www.sumerianoptics.com/products/alkaid/. The site is also in English, top right.

One can hypothize that we Dutch have lots of time to build travel scopes, because of the generally bad weather, and the need to travel far away to be able to see DSO's.

[Dragan]

Hi Sander,

Thanks for the links! I especially like the Sumerian design. Very well designed.

But one thing that attracted me to the HI8 was the fact that it is completely self contained. There are no extra pieces to carry apart from the telescope. For example, the trusses. In the HI design, the trusses are stored within the rocker box. Most other travelscopes need a second piece to carry, whether it be the trusses or a tripod.

The HI8 design is perfect for the airline traveler. One piece of carry-on luggage and its all there.

[MarcE]

Hi Dragan,
exact for the "Airline-traveller-design" i bought the scope, loved the scope and miss the 8 incher right now:-)
But: i enjoyed selling it to you and really be happy that you like my old scope so much!
And as i said: for me it is much simpler to buy a new one if i do not feel so comfortable with my new 14" Traveldob i will get mid of January.
But as you said: there is NO other scope on the market (i know about) which has this "one piece design".
ATM can build a scope like HI with half of the weight, but this is a total different story..
Hope to be back quite soon in the US and hopefully meet you then Dragan.
BR
Marc

[deepskytraveler]

On a recent visit to Dragan's I had the opportunity to see and experience the Hofheim Instruments 8" f/4 Travelscope. Though we were unable to observe with it, I was able to set it up, tear it down, and repack it.
Here are my reactions about this innovative scope.

>Incredibly compact - like there is no way there is a complete 8" dobsonian in that small box.
>Exquisitely engineered and meticulously fabricated. You've got to see it to believe it!
>Assembly and disassembly is simple and easy - it can be ready for observing or repacked in 5 minutes or less.

I can't wait for an opportunity to give this scope a try under some dark skies.

Dragan, good luck with your efforts to make it easier and quicker to purchase this scope here in the States.

-Mark

[Ivan Maly]

Seems like a very well-executed take on the "mount-less" travel telescope. And a fine article, Dragan. I would be worried about stability and eyepiece height range with this type of design, buy hey, it's 8" and it goes into (a big plane's) overhead bin. That's very attractive to this occasional traveler. My travel scope is 6" (carry-on) on a mount (checked) and I'd like more aperture.

[svdwal]

Dragan

Indeed, the Hofheim uses collapsable rulers as trusses, and they apparently work very well, and are very easy to pack in a small space. In fact, one guy I know has one too, and I have seen it once. Never looked through it, though.

These travel scopes are quite interesting from a design point too. If it is too small, it is hard to balance and you need to put it on top of something to get enough eyepiece height. If it is too big it becomes too heavy and it won't pass airline regulations. If it is too slow you cannot get it balanced either, if it is too fast you get ugly stars and get balance problems because of the the heavy eyepieces. The sweet spot is somewhere around 8, 10, 12 inch mirrors with a focal lenght of 1200 mm.