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New Astro-Tech 0.8x reducer/field flattener

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#1 frebie

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Posted 18 October 2012 - 02:24 PM

The new Astro-Tech ATR8 2" 0.8x reducer/field flattener for f/6 refractors is now available from stock. Although designed primarily for use with the new Astro-Tech AT60EDT triplet apo refractor, and priced at only $119.95, the ATR8 will work well with any brand of apo or achromatic refractor with a 2" focuser and operating at a focal ratio of f/5.5 to f/7 or so.

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#2 Mary B

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Posted 18 October 2012 - 03:46 PM

Any news on one for the RC scopes?

#3 Ira

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Posted 18 October 2012 - 04:45 PM

Is this mainly for photographic use or does it apply to visual observers?

/Ira

#4 frebie

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Posted 18 October 2012 - 05:43 PM

Any news on one for the RC scopes?


Nope. Different supplier.

#5 frebie

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Posted 18 October 2012 - 06:00 PM

Is this mainly for photographic use or does it apply to visual observers?

/Ira


Photographic. The image plane falls 55mm behind the shoulder of the reducer, the spacing between the front face of a T-ring and the image plane in a DSLR. There's no room for a diagonal and eyepiece and no easy way to attach them.

#6 tomo

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Posted 24 October 2012 - 07:55 PM

I just picked mine up. It looks just like Orion's one but they don't say it flattens. Same?

#7 frebie

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Posted 25 October 2012 - 10:36 AM

We don't know for sure if it is the same reducer, since we and Orion don't share ordering information. A lot of astronomy products look alike. What we do know is that the manufacturer has very specifically stated to us in writing -- twice -- that our 0.8x reducer, and I quote their email, "is also a flattener."

#8 WhitenerJ

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Posted 02 November 2012 - 08:47 AM

I have an Orion EON 80mm which is F/6.25. Would this work well with it and also what would it drop my F/6.25 down to?

Jason

#9 frebie

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Posted 02 November 2012 - 10:13 AM

It should work with no problems, as f/6.25 is in the right f/ratio wheelhouse, but we have not tried it with that particular scope so no promises. f/6.25 x 0.8 = f/5.

#10 Starrvue

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Posted 18 January 2013 - 09:59 AM

Will this product support a DSLR full frame 35mm camera or is it only intended for the APS size camera?

#11 frebie

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Posted 18 January 2013 - 03:22 PM

The image circle at the focal plane of the 0.8x reducer is 42mm. 35mm film has a 43.3mm diagonal and full frame DSLRs typically have a diagonal measurement of 43 to 43.3mm, depending on the manufacturer. There will be a very small amount of vignetting at the four corners of the image.

#12 Lightning

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Posted 19 January 2013 - 02:30 AM

Funny... it looks absolutely identical bar the white type to my Williams Optics P-flat 88.

[Edit] Oops, it's clearly different. :foreheadslap:

Question: Which scope would this work with better, the AT65EDQ or the AT60EDT? Thanks in advance. [/EDIT]

#13 frebie

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Posted 19 January 2013 - 11:33 AM

We haven't tried it the reducer with the 65EDQ, since the 65EDQ already has a built-in field flattener lens. The field-flattening function of the 0.8x reducer would probably simply undo the field-flattening effects of the scope's built-in flattener and recurve the already flat field.

#14 Lightning

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Posted 19 January 2013 - 07:05 PM

It does look suspiciously similar to this though: http://www.bintel.co...ners/Orion-0...






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