Vixen DED 108SS Refractor helpI have been running a f3 200mm Honders in my Dome for g

[AlanP (Alan)]

I have been running a f3 200mm Officina Stellare Riccardi Honders in my Dome for gathering Luminance and Ha data. It sits next to an AT10RC, so the base level of the Mount is comfortably filled. I bought a 90mm F6.67 Refractor to pull in the RGB [OSC] data [while the Honders handles the B&W], but found that it was too slow to make a simultaneous imaging session sense.

So the challenge was to find a 530mm to 580mm FL fast focal ratio, compact, light weight Scope that didn't break the bank. The closest used offering that I found recently was a lightly used Vixen DED 108SS Refractor. This is a petzval design that Vixen made for a short period of time [2002 to 2004? maybe], to possibly compete with the TAK FSQ106.

The Scope uses two long spacing ED Doublets, with a larger Doublet placed at the Focuser, to minimize potential vignetting. So you end up with an 108mm aperture at f5 focal ratio for a resultant 540mm FL. And because it is a relatively unknown Refractor Model, the resale price was within my budget [as opposed to the heavier, longer and many times more costly TAK 106 Scopes, that have been coming to Market].

Apparently the result is a fast, flat field [a 90mm diameter flat field is indicated by Vixen] Scope that was targeted at 6x9 film Cameras of the time.

I have tried various Online searches to get more information on this Product, but the results have been very limited. Additionally, I don't see any AP images posted from this type of Refractor beyond about 2008. I am hoping that maybe some members of this Forum can help fill in more detail for me. Thanks in advance, AlanP


-> I did try sending a PM to LewisM, again hoping to gain some insight about a Scope that is fairly invisible Online. It is looking as not many of these landed in the States...

[Kunama]

Welcome Alan, I saw your post on CN. Lewis recently bought one of those scopes and has started imaging with it. I think he is moving house at the moment but will no doubt reply soon.
Have a look here:
http://www.iceinspace.com.au/forum/s...hlight=108+ded

[Larryp (Laurie)]

Welcome, Alan

[renormalised (Carl)]

Have a look at this....

http://www.vixenoptics.com/refractors/VSD.html

[LewisM]

Alan,

As per our private messages, you will be impressed with it when it arrives. It gathers an astonishing amount of light in little time, with a supremely flat field. I am thoroughly impressed with mine, just still need to refine focus etc - it's a finicky lady!

Still awaiting the return of my SX camera after repairs, but am using an OLD SBIG ST-8XE in the meanwhile, with very promising results (just cannot get sky time!). Star bloat seems a little issue, though I think almost entirely focus related - as I said in messages, the in-focus range is impossibly small (though the drawtube range is impressively large, accomodating a LOT of cameras etc), so manual focus is really FRUSTRATING (though, I have nailed it ONCE). Auto-focus system required (I have Sharpsky - just have not installed it yet). And of course, ANY slight camera tilt shows up drastically on the images like a miscollimation (which it is!) - the SX cameras with the adjustable faceplate are IDEAL.

Do post pictures when you get it - these scopes are VERY scarce, with only a handful of owners I know (found another this morning).

Oh, and visually - they leave a any scope - including my FL102S - for DEAD. The colour and contrast visually is nothing short of perfection. I know you own an FL102S too,so you will be amazed I think. It's just a delightful scope, killed off by the simple fact Vixen could NOT keep the cost down to keep them competitive.

[LewisM]

BTW, this was the WORST CCDInspector result I got with the DED108SS (slightly over-corrected), which is still, in my opinion, impressive enough!

Not entirely flat, but darned close! A TINY crop of the image removes the VERY small coma at the EXTREME edges of the frame.

[AlanP (Alan)]

Thanks for all the welcomes. So a Yankee is welcome to the club?

For the imagers out there, my website is mystarrynight.info
The most recent Scope Pack at the House has a 200mm Officina Stellare RHonders sitting next to an AT10RC, as I indicated in the earlier Email. I mention this to point out the current Pack in my website images, as there are also images of the earlier stuff. I think the changing of the Celestial Heavens force us to change our Equipment too... It's not our fault! We are compelled by forces beyond us...

To any O/S RHonders people out there, I am buying a second used Scope to put at my my Cottage POD next to an AT6RC [for the OSC].

Our skies have been overcrowded with more and more clouds as the years accumulate. So I have been trying to simultaneously image Luminance and OSC to get all the data in one pass on the few clear nights. One Scope images Luminance/guides and the second pick up OSC while using AO to correct flexure.

While this works well for dark clear skies. the Moon still ruins OSC, when it is more than ~25% present. So much of the current data is Ha off the Honders. Eventually I will pick up OIII and SII to loop back through this Ha collection. And maybe I will be granted some Color too.

Thanks for the welcomes. If I can help, please let me know. AlanP

[brian nordstrom (As avatar)]

Hi Alan , and a big welcome from me as well .
Lovely scope you are getting and I hope it all works well for you .
Brian.