Quote:
Originally Posted by sejanus
thanks heaps for that info Greg.
One question - does the 106ED vignette at all with the f/3.6 reducer?
edit - also, if you had to buy a Tak 106 - what would you get these days? The N or the ED? Price aside...
cheers
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Yes there is vignetting with the reducer but it corrects with flats. All scopes that I have used do not produce an image that is even all the way across the image. Some require flats more than others. The Tak BRC250 for example, the FSQ106ED with reducer even the AP140 with reducer. But then the flats totally handle it. So is that really vignetting like you asked (implying something that can't be corrected in processing?) then no it does not vignette.
Now you've put me on the spot. I currently have the 106EDX with a camera angle rotator (one of Taks great accessories - such a nice piece of gear I am surprised other manufacturers don't copy it).
I think I would stick with the 106ED as I really like the reducer.
It also is smaller (shorter). The microfocuser is as good as it gets (better even than a feathertouch). The other points are small issues really.
As I say you'd be ecstatic with either. If money were an issue then the 2nd hand prices of nice 106Ns with rings etc would be really tempting knowing that in some ways it is better than the 106ED. If the reducer (which is not everyone's cup of tea) was your thing then the 106ED is the go. No other scope really can match it for the money - F3.65, pinpoint stars to the corners of a 16803 chip and 106mm aperture - WOW. If you wanted to use binoviewers then the 106ED is the choice (not sure you can even use binos on a 106N - probably not).
You are really comparing a US$2800 or even less scope (106N) with a US$4500 scope (106ED with rings etc). So its quite a bit more for the EDX. You might even scope a 106N with quick release finder brackets and a finder scope and a case for that sort of money. So they are a bargain for what is still a magnificent scope.
Plus when you bring it in GST is calculated on the higher price as well making the difference in price even more.
When considering the price, I say the 106N is the clear winner unless you really want the reducer or use binoviewers in which case the EDX is the go. If you want perfect colour correction then the 106ED is the go.
Greg.
Quote:
Originally Posted by jase
No, the differences are marginal Greg. If presented with data of the same target from both instruments, you'd be hard pressed to distinguish the difference.
Saturation is the dominance of a hue in a colour and is often referred to as colour intensity. What ever you wish to call it, it has very little to do with the instrument, but post processing. You can make hues pure (saturated) or grayscale (desaturated) as you see fit. To make sure we are all clear on the differences between hue and saturation, I've attached the below chart (no idea where it come from as I found it in work course material!). As you move into the center of the wheel, the hue of a particular colour becomes less dominate. At the center, no hue dominates and is therefore considered fully desaturated. Saturation is the dimension running from the outer edge of the wheel (fully saturated) to the center (fully desaturated). It is possible to reach the same level saturation with ED glass through post processing (if at all needed).
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I probably have all my 106N data. I may image the same target one day just out of interest to see if what you say is true (it may well be).
I think it was more the coatings rather than fluorite versus ED glass where the difference is a subtlety rather than a heavy difference. Both are amazing but I would always opt for fluorite all other things being equal if I could get it. The new coatings have an almost mustard colour whereas they used to be a grass green. I am sure the 2 coatings do not have the same properties. Roland Christen has done quite a lot of work on coatings. Roland talks down fluorite but then Tak used fluorite for years and marketed its advantages. TEC is now about the only fluorite scope maker. Yuri says there is a measurable difference but I think he mainly uses it to achieve faster F ratios with the same or better colour correction. Certainly my TEC180 has perfect colour correction - zero. Which is good for an F7 scope. But then so does my ED glass AP140 which is F7.5.
Roland produced that custom made 206EDF for Tony Hallas and put a lot of attention getting high end coatings. Tony's images with that instrument broke new ground on familiar objects much like the ASAs did at one point in Wolfgang's hands. It would seem coatings are a little world in themselves with their differences and qualities. But the highend coatings cost a lot so what we get on our scopes is not the same as what Tony Hallas got.
For the same price range this scope would outperform either of them, an AP130 F6 for $4000 negotiable - thats about $1900 under normal price unless there is something wrong with it:
http://www.astromart.com/classifieds...fied_id=691236
Oh I see, the guy has no ratings. Hmm - could be a scam. He has no posts, not posted an image, not posted anything, not sold anything before and suddenly a high end AP for $1900 less than normal. Risky.
Or this a Televue NP127is for $4700 (he'd probably take $4500 or less):
http://www.astromart.com/classifieds...fied_id=690526
I have also seen a Tak TOA130 on Astromart recently for under $4000. That would be hard to beat and better than
an FSQ106 in that it is a more versatile instrument (FSQ is really only widefield). There is a nice reducer available on a TOA130
and an extender as well giving F5.25 and F11 or so. It would need a G11 or better mount to handle it though.
There is quiter a large amount of choice around the US$4000 band and a larger aperture scope can be gotten.
I saw a TMB 152 going quite cheaply recently as well. The US guys are hurting financially so low demand plus the need for cash = bargains for us (for a change).
Greg.
Quote:
Originally Posted by jase
The captains wheel certainly does suck when it comes to imaging. If you happen to also have the finder scope attached you can't rotate the imaging train a full 360 degrees as it typically bumps into the dovetail or mount plate. Very restrictive.
Not only that, if you want to do any framing/composition remotely, rotating the capitan wheel isn't an option. So you're left with the only option of locking down the wheel and putting on a CAA with Astrodon Takometer. That effectively turns a regular FSQ106ED into and EDXII as this is what Tak now provide (as you note Greg) to address such an issue. The captain's wheel was a bad idea IMO. With the CAA, rotating the camera is a breeze, even with a payload of MMOAG, U16M/wD9 cooling and filter wheel.
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Yes the captains wheel was a bad idea. It was a nice feature on the Tak BRC250 which is perhaps where Tak got the idea from to use it on other scopes. But on the BRC the corrector had to be kept at the same distance from the primary mirror so the captains wheel made sense (the corrector fitted inside the captains wheel).
Greg.
