First glimpse of the Explore Scientific 16" Dobsonian

[emadmoussa]

At Astrofest, ES lead designer, Tassilo Bohm, told us they were working on a 16" version of their 'extra-light' 12" truss Dobsonian.

Apparently, it's not on the market yet, but there are some glimpses on the design.

Manufacturer: Explore Scientific
Aperture: 405mm
Focal length: N/A
Diameter reduction: 50.8 mm
Control: manual
Total weight: 32kg
Light gathering power: 3347 ×
Resolving power: 0.34 "
Minimal magnification: 58 ×
meaningful Maximum magnification: × 810
theoretical maximum magnification: × 1157

It seems slightly more compact than the Sky-watcher or Orion 16"...which I think is a plus point. However, a shorter focal length means more fussy collimation.

Let's wait and see.

[emadmoussa]

There's also a hypothetical list of prices for 10", 12" (we already know ) and 16"

16" Explore Scientific Gitterrohrdobson - 1999,00€ (NOT BAD actually)..
12" Explore Scientific Gitterrohrdobson - 999,00€ (cheaper now)
10" Explore Scientific Gitterrohrdobson - 599,00€

[michael.h.f.wilkinson]

Interesting stuff. The design looks a bit like the ones sold under the Omegon brand by astroshop.eu

[emadmoussa]

If the 16" functions mechanically as the 12" which we had a play with at Astrofest...then we're up for good stuff.

[emadmoussa]

Interesting stuff. The design looks a bit like the ones sold under the Omegon brand by astroshop.eu

But there's a massive difference in price...

[crashtestdummy]

I dont like the open nature of the top bit,way too easy for stray light to enter.and why do they insist on putting cheap rdf on them?

[emadmoussa]

As a matter of fact on close examination the RDF is a good quality piece of kit. But why would I care? I usually get rid of the stock accessories anyway...

[michael.h.f.wilkinson]

But there's a massive difference in price...

True, but the Omegons are supposed to have Hilux mirrors, and can be supplied in 1/6, 1/8 or 1/10 lambda surfaces. The travel versions are certainly light.

ES does look interesting, but I await specs on the mirrors.

[swamp thing]

I dont like the open nature of the top bit,way too easy for stray light to enter.and why do they insist on putting cheap rdf on them?

I agree.

I would like to see how the all metal design deals with vibration dampening too.

I have used some all metal dobs that vibrate like tuning forks in the past.

[emadmoussa]

True, but the Omegons are supposed to have Hilux mirrors, and can be supplied in 1/6, 1/8 or 1/10 lambda surfaces. The travel versions are certainly light.

ES does look interesting, but I await specs on the mirrors.

When we examined the 300P flextube which was sitting near the Explore scientific 12" Dob, we noticed (maybe in our eyes) that the primary mirror on the 300P was slightly bigger even though both had the same aperture.

[Pig]

One of the interesting features Tassilo showed us at the Astrofest is you can collimate it whilst you are observing through the eyepiece.

Is this a common feature with Dobs?

If I do not get a Solar scope next I may go for the 12", it is extremely well thought out for portability and good for dew control.

I will of course investigate the tuning fork theory as vibration, in my opinion, is probably the worst attribute of all.

[Mike73]

True, but the Omegons are supposed to have Hilux mirrors, and can be supplied in 1/6, 1/8 or 1/10 lambda surfaces. The travel versions are certainly light.

ES does look interesting, but I await specs on the mirrors.

I think that when you start getting to 16"+ the ultra high grade mirrors become less desirable because you don't see any benefit from them on DSO's, even a HiLux coating will only give you roughly a 5% brighter view which I think most people would struggle to notice.

If I had the money to get either a 16" 1/10pv or a 20" 1/4pv I would get the 20" without a doubt.

[Mike73]

One of the interesting features Tassilo showed us at the Astrofest is you can collimate it whilst you are observing through the eyepiece.

Is this a common feature with Dobs?

Collimating a large dob can be tricky because of the focal length but it easy to get around if you use a bar lowed laser of Hotech collimator so although you can collimate the ES at the eyepiece using the rod its certainly not a deal clincher, handy to have but not essential.

[Pig]

Collimating a large dob can be tricky because of the focal length but it easy to get around if you use a bar lowed laser of Hotech collimator so although you can collimate the ES at the eyepiece using the rod its certainly not a deal clincher, handy to have but not essential.

Thank you Mike. I do like handy things though  they kind of come in handy.

[emadmoussa]

Collimating a large dob can be tricky because of the focal length but it easy to get around if you use a bar lowed laser of Hotech collimator so although you can collimate the ES at the eyepiece using the rod its certainly not a deal clincher, handy to have but not essential.

ON many occasions handy does matter physically and psychologically. That's the whole point of 'improved' design - doesn't add extra features but rather tweak existing ones and make them easier to handle which in turn saves time and effort.

I can't speak of the optical quality, but I can certainly tell you that mechanically the 12" which we fiddled with was well thought of. The balance element in particular was very good. Despite having a heavy eyepiece the scope didn't seem to lose balance upon lowering all the way down. For all of us who use heavy 2" eyepieces - including me - this feature is pretty useful. While my 12" is better balanced than my 10", I found the ES 12" more self balanced than both. Perhaps because of less metal and hence weight...I'm not sure.

From what I read and heard, beyond 16" optical quality (speaking of margin differences, not great vs rubbish) seems to matter less, as far as DSOs is concerned, as Mike72 remarked.

[Pig]

I wish you guys would stop making me want more and more scopes   Blinking nuisances all of you   I do like the black and yellow combo, its kind of waspish.

[Mike73]

ON many occasions handy does matter physically and psychologically. That's the whole point of 'improved' design - doesn't add extra features but rather tweak existing ones and make them easier to handle which in turn saves time and effort.

I can't speak of the optical quality, but I can certainly tell you that mechanically the 12" which we fiddled with was well thought of. The balance element in particular was very good. Despite having a heavy eyepiece the scope didn't seem to lose balance upon lowering all the way down. For all of us who use heavy 2" eyepieces - including me - this feature is pretty useful. While my 12" is better balanced than my 10", I found the ES 12" more self balanced than both. Perhaps because of less metal and hence weight...I'm not sure.

From what I read and heard, beyond 16" optical quality (speaking of margin differences, not great vs rubbish) seems to matter less, as far as DSOs is concerned, as Mike72 remarked.

Sure I understand what you mean but the only benefit that I can see that it gives is you'll be able to use a standard cheshire collimator which itself can be a real pain to use when setting up in the dark at a dark site and is another reason why I use a focus cap and Hotech. Apart from that it doesn't really improve on existing methods of collimating big scopes.

[emadmoussa]

I wish you guys would stop making me want more and more scopes   Blinking nuisances all of you   I do like the black and yellow combo, its kind of waspish.

If you're going Dob, perhaps go 12" plus I'm not seducing you into the realm of empty pockets...Nah, I am!!

[emadmoussa]

Sure I understand what you mean but the only benefit that I can see that it gives is you'll be able to use a standard cheshire collimator which itself can be a real pain to use when setting up in the dark at a dark site and is another reason why I use a focus cap and Hotech. Apart from that it doesn't really improve on existing methods of collimating big scopes.

Ah well, reflector telescope can be high maintenance, especially the bigger they get. Let alone they infect you with the OCD virus.

[Pig]

I think I will have to go up at least a couple of inches more, I kind of liked that Orion Dob we saw. I think it was 16" about 3K if I remember rightly

I think I have some loose change hanging about

[emadmoussa]

I think I will have to go up at least a couple of inches more, I kind of liked that Orion Dob we saw. I think it was 16" about 3K if I remember rightly

I think I have some loose change hanging about

Yeah, the Orion ones were great. I think it was £3800...even without the top ring

[emadmoussa]

Oh, the original image showing the 10", 12" and 16" is gone...!!!

Here's it is again...

[Pig]

I can just see the look on the other halfs face if I bought one

I would have to lie to her otherwise she would book a very expensive holiday

[emadmoussa]

I can just see the look on the other halfs face if I bought one

I would have to lie to her otherwise she would book a very expensive holiday

I'm already throwing hints about the 16" if we moved house....internalization methodology so she won't be shocked!!

[michael.h.f.wilkinson]

I sense a collective bout of aperture fever coming on