Jump to content

  •  

CNers have asked about a donation box for Cloudy Nights over the years, so here you go. Donation is not required by any means, so please enjoy your stay.

Photo

Field flattener for ED80

  • Please log in to reply
9 replies to this topic

#1 JeffreyHorne

JeffreyHorne

    Explorer 1

  • -----
  • topic starter
  • Posts: 50
  • Joined: 22 Apr 2013

Posted 19 February 2019 - 11:45 AM

Hello friends, and thanks in advance. 

 

My my father is letting me borrow his ED80, so I can get some wider FOV shots than with my C8.

 

He’s mentioned, and I’ve read, that I’d probably want to use a field flattener with the ED80 if I’m going to do imaging. 

 

Explore Scientific’s 2” field flattener is on backorder for months (heard directly from them.)

 

What brand/type of field flattener do you recommend for the ED80?

 

Thanks!

Jeffrey



#2 joelin

joelin

    Surveyor 1

  • *****
  • Posts: 1653
  • Joined: 14 Jan 2008
  • Loc: Saratoga, CA

Posted 19 February 2019 - 12:02 PM

I'd say this one: https://www.telescop...ctor/p/5195.uts ?

 

It flattens and reduces slightly. It's threaded so camera connections will be solid. 


Edited by joelin, 19 February 2019 - 12:03 PM.


#3 ngc7319_20

ngc7319_20

    Ranger 4

  • *****
  • Posts: 312
  • Joined: 25 Oct 2015
  • Loc: MD

Posted 19 February 2019 - 12:37 PM

The TeleVue 0.8x worked OK on my ED80.  

https://agenaastro.c...r-trf-2008.html



#4 JeffreyHorne

JeffreyHorne

    Explorer 1

  • -----
  • topic starter
  • Posts: 50
  • Joined: 22 Apr 2013

Posted 19 February 2019 - 02:38 PM

Do either of you know how using a field flattener/corrector with a refractor like this matters if using a full frame vs crop sensor?

#5 ngc7319_20

ngc7319_20

    Ranger 4

  • *****
  • Posts: 312
  • Joined: 25 Oct 2015
  • Loc: MD

Posted 19 February 2019 - 03:53 PM

The blur diameter is something like 14 pixels in the APS-C sensor corner without the flattener (assuming Canon 60D 4.3 micron pixels).  For full frame sensor the blur is about 36 pixels in the corners.  So either way you want a flattener.



#6 Darrenlh

Darrenlh

    Vostok 1

  • -----
  • Posts: 176
  • Joined: 08 Sep 2010
  • Loc: Alberta, Canada

Posted 19 February 2019 - 04:40 PM

I can personally recommend this flattener also from Orion:

 

https://www.telescop...yword=flattener

 

It comes in at a reasonable $139, but isn't a reducer. It works excellent with my Nikon D7200 (APS-C) and Skywatcher 600mm ED80 F7.5

 

I get sharp stars all the way to the edge.



#7 OrionSword

OrionSword

    Mariner 2

  • -----
  • Posts: 274
  • Joined: 14 Aug 2010
  • Loc: Colorado

Posted 26 February 2019 - 06:22 PM

The Hotech SCA did a good job on the ES ED80 I had, now using it on the Stellarvue SV80ST.  You need 55mm of back focus from the flattener to sensor.  Agena says 56mm which does not match the packing sheet.

 

https://agenaastro.c...-flattener.html


Edited by OrionSword, 26 February 2019 - 06:23 PM.


#8 droe

droe

    Viking 1

  • *****
  • Posts: 738
  • Joined: 01 Jul 2015
  • Loc: Fenton, Mi

Posted 27 February 2019 - 11:33 AM

I did a comparison of the Orion FF and Reducer here. Hope it helps.

 

https://www.cloudyni...or-es-80mm-apo/



#9 GraySkies

GraySkies

    Vostok 1

  • -----
  • Posts: 165
  • Joined: 25 Feb 2011
  • Loc: Ontario, Canada

Posted 28 February 2019 - 10:53 AM

I have a William Optics ZenithStar 80mm f/6.8 II ED APO Refractor and I use the WILLIAM OPTICS FLATTENER 4 - 0.8X REDUCER with great results

https://optcorp.com/...cer-flattener-4

[It replaced a Meade Series 4000 Focal Reducer / Field Flattener I was using previously which now sits on a shelf]



#10 Steve OK

Steve OK

    Apollo

  • -----
  • Posts: 1470
  • Joined: 22 Sep 2007
  • Loc: OKC, OK

Posted 01 March 2019 - 11:20 AM

I just got the one made for Orion for my ED80, the Orion Field Flattener for Short Refractors.  It seems to do a good job. 

 

Here's an image with it in place.  I don't have a "without" image to compare, but this image has tighter stars at the edges than I ever saw without it.

 

click for a larger image:

M-37-CN.jpg

 

Steve




CNers have asked about a donation box for Cloudy Nights over the years, so here you go. Donation is not required by any means, so please enjoy your stay.


Recent Topics






Cloudy Nights LLC
Cloudy Nights Sponsor: Astronomics