OVL Field Flattener

OVL Field Flattener

  (12 Reviews)
✓ 2 year warranty


Usually shipped 20-25 working days.
Request a Price Match

About this product

Model:  skywatcher_field_flattener
Part Number:  20225

A high-quality, non-focal-reducing Field Flattener optimised for DSLR imaging on refractor telescopes with focal ratios around f/5.5 to f6.0. 

Will also provide much improved results on refractors with focal lengths narrowly outside this optimised f/range.

Integral T-Ring adaptor thread. High quality CNC machined body with gloss black anodised finish.

Features standard 2" push-fit barrel for use with 2" focusers.  Threaded for 2" filters.

Customer reviews

Average Rating (12 Reviews):  
Write a Review and share your opinions!

Rating (max 5):  
OVL Field Flattener works flawless with Fullframesensors!
Friday, 14 February 2020  | 

The OVL Field Flattener works very well on my Skywatcher 72ed refractor telescope! It corrects the stars completely up into the corners of my fullframe sony camera! For this price its amazing! For those who dont want to loose Focal Lengh its the best way to go imo

Rating (max 5):  
Much friendlier option than the SW reducer/flattener
Monday, 30 September 2019  | 

£100 less than the "optically matched" reducer/flattener from SW which is not even optically matched, just frankenstiened from the the ED80's reducer/flattener.
Doesn't reduce the focal length, just provides a flat field across 95% of your crop frame image.
1 Star removed as my barrel literally came superglued into the fixture that it is supposed to unscrew from, tore my hands apart trying to get it removed, ended up having to spend an extra £15 on some rubber loop wrench's to unscrew it, upon unscrewing it, there was clearly superglue residue (or some kind of rubber sealant) in the threads, once removed, my screw in focus tube adaptor for the 72ED connected without issue.

Rating (max 5):  
Good work.
Sunday, 18 August 2019  | 

Very Solid making. nice clear lens. Can connect with telescope both 2" nosepeace and 48mm.

Rating (max 5):  
Sunday, 10 February 2019  | 

Prix excellent et envoi rapide, pas encore plus le tester faute de mauvais temps, mais FLO a fait sont travail et très bien.
Je vous remercie encore car il n'est pas facile à trouver et même introuvable en France.

Rating (max 5):  
Un envoi parfait
Wednesday, 19 December 2018  | 

Très content de ce produit. Merci Flo.
A bientôt

Rating (max 5):  
Great value for a simple flattener
Tuesday, 3 July 2018  | 

Bought this for the new SW 72ed and it is just perfect.

Less than 80€ and does the job, exactly what I needed. Thanks flo.

Rating (max 5):  
Skywatcher Field Flattener
Thursday, 3 July 2014  | 

I bought this to try and flatten the field on my TS 80mm triplet F6 scope when using it with a Nikon DSLR. Without it, the scope was producing unusable images where the stars towards the corners were more like streaks than round stars. Once I included this field flattener however the results were transformed. Perfect round stars across the entire image. I also managed to connect my filter wheel between the flattener and the scope and was still able to achieve focus so I'm really pleased.

One point worth mentioning is that the nosepiece is quite long and was initially hitting the inside of the focuser before reaching the flange so you might want to look at a lower profile version. Since I took this off to attach the filter wheel, which has a low profile nosepiece anyway I now have a solid unit.

I would recommend this flattener to anyone using a DSLR and a fast refractor. Totally worth the money.

Thanks again FLO

Rating (max 5):  
Superb flattener
Monday, 13 January 2014  | 

I bought this for use with an Equinox 66. I had to purchase a low profile SCT to T thread but the bonus is that with the flattener and a 2" LP filter its all focussed without adjustment (fully racked in). As for the performance of the flattener, it works perfectly. Some comparison pics can be found here http://stargazerslounge.com/topic/200692-equinox-66-advice/

Rating (max 5):  
Great Flattener
Saturday, 6 July 2013  | 

Bought to go with Equinox 80 and QHY9M with QHY USB wheel. Great round stars right to edge of field with no change to focal length. Used at 52mm from sensor. Clear skies

Rating (max 5):  
It works at f/6.25
Monday, 6 June 2011  | 

Bought this to go with the Skywatcher Equinox 80 APO PRO OTA f/6.25 and a canon 7D. Flattener screws directly into the T to EOS adaptor. Corner stars are now very good and round.

Read all 12 customer reviews...


Please fill in the form below to ask a question or request a price match.

Your Name:
Your Email Address:
Your Question / Request:
URL of the Cheaper Price:
If you are requesting a price match please let us know the URL where you have seen the product cheaper.

Related Products
Astro Essentials T Rings

Covid-19: We are open for business as usual. Some deliveries are a little delayed. All deliveries are contact free. Thank-you for choosing FLO 🙂