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Show us your Frac


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My Helios 6" f/9.4 went to a new home this morning and this little beauty came home as part of the deal...

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Skywatcher Startravel 120 f/5

Now fitted with a Skywatcher Dual-Speed focuser.

Looking forward to some nice wide field views and perhaps some DSLR action through this one :grin:

Edited by DRT
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Nice Derek :) I've always wondered if using a semi apo filter would make imaging possible with one of these scopes?

I have a Baader Semi-Apo, Chris, and now also have an EQ5 with tracking motors so will be giving it a go. I don't have the patience for all this stacking malarky but will be trying to get some good single long-exposure shots :smile:

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Mark from Moonraker took some of his scopes to the NEAF this year in the US:

I think if they had a "best in show" award he would have won it !

I am in love with all of them truly. Would be happy with multiple moonrakers haha, but if I had to choose, it would have to be:

NEBULA CLASS F13 100MM & F15 80 MM or F12 104mm

Probably the F15 80mm because I have a 100mm scope now and that is an impressively long focal length.

Edited by Tyson M
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Refractive family portraits...

Takahashi FS-102, a 102mm f/8 apochromat...

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Purchased new in 2003, it is a consummate "pupil", my having split Sirius in the same year when it and its companion, "The Pup", were practically adjacent to each other; said companion having blinked in and out, but never having disappeared entirely within the Dog's intense glare.  The separation between the two has steadily increased since that time.  I attribute said feat to the refractor's exquisite calcium-fluorite doublet, known for its relative absence of light-scattering...

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Tanzutsu 60mm f/15 achromat, and upgraded to a 1.25" focusser...

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Made in Japan in 1987 or '88, this example was purchased as new old-stock earlier this year.  Almost 5" had to be cut off of the optical tube, from the front, and in order to effect the new 1.25" format.  An extra tube-baffle was added, and ultra-flat black spray paint applied throughout the optical path where necessary, from the front edge of the dew shield to the 1.25" visual back.  I had always wanted a long-focal achromat, albeit only a 60mm.

Lastly, the most recent acquisition: an Antares 805 80mm f/6 fast-achromat...

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It, too, will need enhancing, but as it stands I was able to view the Airy disc of the brightest star within Orion's Trapezium, designated "C", rather distinctly and under high magnification.  Nonetheless I consider it to be little better than a guidescope with less than stellar optical quality.

An afocal image via the Takahashi, and simply by holding a point-and-shoot camera up to the eyepiece...

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Likewise, via the Tanzutsu...

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...and via the Antares...

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Chromatic abberation is well-controlled with this example, but present nevertheless.

In every instance, the Canon S110 always falls short of that seen during a live session.

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Nice pics of the scopes :smiley:

In that last one of the moon, it looks like the CA around the limb varies in tint from the top (greenish) to the bottom (blueish). I've not seen that before. Usually you see it as per your other two photos, a consistent colour around the limb, changing colour, again consistently, as you rack through the focus point.

Does the Antares show that visually or is it a photographic artifact ?

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That's quite a strong colour cast through the Tak. Was it a TeleVue ep by any chance?

The Moon was almost full, waning I think, when I took that photograph, thus the use a variable polariser to dim down the brightness.

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Nice pics of the scopes :smiley:

In that last one of the moon, it looks like the CA around the limb varies in tint from the top (greenish) to the bottom (blueish). I've not seen that before. Usually you see it as per your other two photos, a consistent colour around the limb, changing colour, again consistently, as you rack through the focus point.

Does the Antares show that visually or is it a photographic artifact ?

At f/6, 480mm, the Antares will indeed exhibit its fair share of false colouration, and the camera only accentuates it further in the resulting photograph.  I've been told that the camera itself, even, will introduce colours, particularly when held at an angle.  Here's another shot through the Antares, and at a higher magnification.  However the colour wasn't as strong when observing with the eye...

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In every instance, the Canon S110 always falls short of that seen during a live session.

As a spectacle wearer I can vouch for the fact that the eye/brain combination is very good at doing on-the-fly RGB alignment. It can be fooled, illuminated TESCO signs in red and blue and the HSBC logo on a computer screen both show movement of the two coloured parts when I move my head - in fact the red spelling wiggle under TESCO moves side to side as I shake my head! But when the colours are overlaid, the eye correct (e.g. the word TESCO in white doesn't split into RGB except at the extreme edge of my vision, even though the red bit must be moving as much as the wiggle!)

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As a spectacle wearer I can vouch for the fact that the eye/brain combination is very good at doing on-the-fly RGB alignment. It can be fooled, illuminated TESCO signs in red and blue and the HSBC logo on a computer screen both show movement of the two coloured parts when I move my head - in fact the red spelling wiggle under TESCO moves side to side as I shake my head! But when the colours are overlaid, the eye correct (e.g. the word TESCO in white doesn't split into RGB except at the extreme edge of my vision, even though the red bit must be moving as much as the wiggle!)

I'm near-sighted, and have worn glasses since my relative youth. 

In any event, what I had meant by my statement regarding the camera's shortcomings, is in that it fails to capture the sharpness of a live view.  This is a photograph I took with the Tanzutsu 60mm f/15...

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It appears nice and sharp, eh?  Ah, but not nearly as sharp as the live view at the time the photograph was taken.  Here's a close-up...

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During the live view, within the circled portion, I saw what appeared to be dozens if not hundreds of what I term "hills and dales", within that ridge.  The event has me almost convinced that the achromatic doublet was not manufactured by Tanzutsu, but by the Japanese optical house, Towa, instead.  The two companies were in collaboration with one another at some point in the past.  I wouldn't be surprised if the doublet was a part of Towa's old stock, and possibly from at least a decade prior to the refractor's manufacture.

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Nice series of images, it's interesting to see the difference imaging wise between different scopes :) Maybe you could start a thread called 'show us your Moon image' ;) Seriously though, that might be a pretty good idea for the imaging section :)

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That last image shows the Lunar Apennine Mountains. The Apollo 15 landing site is in there. You can see the Hadley Rille and Mount Hadley with high magnifications through my 12" dobsonian.

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Haven't visited in a while. Some really great scopes here. I might be getting a 4" F/6.5 achromat some time soon, to make EVEN bigger solar H-alpha mosaics :D

Thats the same spec as my Vixen ED102SS Michael, except that it's an ED doublet. I ought to try a Quark in it sometime, I believe it's the right sort of specification for that device.

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