Dream scope,small (maybe not) issue...

[LewisM]

I finally found my dream scope. The price is RIGHT, and all is there, but only 1 issue - there is a patch of striated / filamentous mould behind the first element of the objective (a 4 element refractor). The patch is roughly the width of the first finger tip.

Naturally, this would need to be cleaned off, but being a 4 element design, this could well throw collimation off unless I marked the position of the lens first. BUT, if there is mould already, is there every chance it has "eaten" through the coatings (it is ED glass)? Realistically, how much degradation could occur from such an instance?

Attached is a shot of the objective. Dusty outside, but note the mould striation at 1 o'clock.

I want it badly, but is this a deal breaker? Would UV tend to thwart this one?

It's an UNCOMMON scope, rarely seen any more.

[Larryp]

Personally, I would not touch it, Lewis

[LewisM]

I keep trying to talk myself INTO it, but.... I BADLY want the darned thing.

[rmuhlack]

what benefits does this new scope offer over the FL102S?

The Vixen is extremely well regarded, so i think that this new alternative would have to be orders of magnitude better to even contemplate - and even then only if the optics were to be professionally cleaned and re-collimated.

If it was me, I'd give this new alternative a miss

[casstony]

Find out the cost of returning it to the manufacturer for servicing and deduct that from the fair purchase price of a good sample?

[LewisM]

It is a Vixen Richard - a DED108SS :) Vixens answer to the Tak FSQ106.

Not replacing - HELL NO! Supplementing.

[rmuhlack]

I see the attraction. However, the FL102 with focal reducer has a FL of ~640mm, vs the DED of 540mm. So from an image scale and FOV perspective they are very similar.

A quick google around also suggests that collimation of the 4-element design was problematic, and a star test prior to purchase would be advisable. (However if you get Vixen to clean the optics they would re-collimate it as well). If collimation is potentially a problem with the DED, then compared with your FL102S which you know has perfect collimation and outstanding colour correction, i still reckon you're better just sticking with your current fluorite frac.

The main attraction as I understand it of the DED would be the enormous corrected image circle. Again, unless you're looking at getting a KAF16803 is an image circle that large necessary?

Personally, i reckon you'd be better off getting a second mount instead of the DED, then you can run your FL102S and your new VC200L in tandem on separate targets and double your image output... :)

[LewisM]

Well, yeah... I have talked myself out of it, and being off-shore just adds to the problems. Getting it resurfaced by Vixen is not an option, financially IMHO.

I did just trade for an R200SS too, so happy there - will be a 3 Vixen household :)

2nd mount... now we are pushing it :) The GPD2 can handle all 3 (not simultaneously!) without hiccup, and the PE is REMARKABLY small, so... :)

[rmuhlack]

Fair enough.



Haha, I know what you mean - my casual suggestion at home the other day of a second GOTO mount was swiftly vetoed :lol:

I might just have to surreptitiously get a motor drive for the freebie EQ2 I picked up earlier in the year, to make a DIY budget version of a Polarie/Astrotrac for widefield shots with a camera lens. ;)

[LewisM]

Ah, sir, thou should contact me - I have such :)

[Kunama]

Lewis,3 Vixen household ????? its the redheaded Vixen you should be worried about, just make sure you give priority to that one !!!!! ;)
With all this spending you need to remember that you sleep several hours a day and she knows where the sharp knives are !:rofl:

[LewisM]

Oh thanks Matt - instill fear and loathing in me...

Thanks... and I was going to leave the scopes to you in my will. Now Richard get's em :)

[Kunama]

C'est la Vie !

[rmuhlack]

lol :)