William Optics Adjustable Flattener 73A for ZS73
William Optics Adjustable Flattener 73A for ZS73William Optics Adjustable Flattener 73A for ZS73William Optics Adjustable Flattener 73A for ZS73William Optics Adjustable Flattener 73A for ZS73

William Optics Adjustable Flattener 73A for ZS73

  (6 Reviews)
✓ 2 year warranty


1x in stock shipped 1-2 working days

About this product

Model:  wo-flattener-ZS73A
Part Number:  P-FLAT73A

New Adjustable Dedicated Flattener 73A for William Optics ZS73

Optically-matched 1:1 Flattener for ZS73 APO

Suitable for use with sensors up to APS-C. 

Integrated camera rotator.

Internal thread accepts 2" astronomy filters.

Requires an M48 threaded T-ring if using a DSLR camera.

Recommended distance for the ZS73 is 11.4mm

Note: Loosen the three grub-screws before removing the telescope's anodised eyepiece adapter.  

Customer reviews

Average Rating (6 Reviews):  
Write a Review and share your opinions!

Rating (max 5):  
Excellent purchase!
09 August 2022  | 

Very well made, excellent quality and craftsmanship.
Found the camera rotator part to be very useful, but also very stiff to move, then discovered that there are grub screws that can be lossened slightly to enable rotation without unnecessary force.
Very pleased with the Z73 flattener and the wonderful service from First Light Optics. Thankyou.

Rating (max 5):  
A must-have for imaging.
15 March 2022  | 

My main interest is in astrophotography so a field flattened is pretty much mandatory. The 73A is a beautifully engineered item. Attaching it to the Zenithstar 73 was simply a case of removing three small grub screws from the telescope with an allen key and then screwing it on. The allen key isn’t provided so you will have to make sure you have one to hand.

The field flattener does its job superbly. With a cropped sensor on a DSLR, stars were pin-sharp from edge to edge. I have not yet attached my dedicated astronomy camera and filter wheel but I am confident the adjustable flattener will enable me to reach the perfect back-focus without the need for countless spacers. A must-have for imaging!

Rating (max 5):  
A must
17 June 2021  | 

Beautifully built and a pleasure just to hold. The flattener is adjustable and also has a very smooth camera rotation ring and in-built filter thread so it really completes the Zenithstar to a very satisfying unit. Because of manufacturing delays I received my scope weeks before the flattener and wouldn’t bother using the 73 without it if, like probably most people buying WO, used for photography. Stars are pin-sharp from edge to edge but without it looks terrible in the periphery. Highly recommended

Rating (max 5):  
Order and receiving items
18 March 2021  | 

Same comments as my order for the William Optics Z73 OTA. I look forward to using it!! Stoopid clouds

Rating (max 5):  
William Optics Adjustable Flattener for Zenith Star 73
01 July 2020  | 

Wow what a difference this Flattener has made.Typical of WO the build quality is first rate,it really is a solid piece of construction.The added beauty of this little gem is in the title,adjustable.
No more messing around with spacers(unless of course your camera requires more back space than the adjuster can give,but i would think that would not be the case.
Also because everything is screwed to the scope,no more sag that can be introduced with thumb screws.Required back space is so easily done.
I can thoughly recommend this Flattener for your Zenithstar 73.
No regrets with this purchase,and of course the exerllent service provide by Firstlight Opics.

Rating (max 5):  
Excellent - no messing with spacers
11 November 2019  | 

This is a superb flattener, it is beautifully made and the ability to adjust it without resorting to spacers is a massive benefit. Combined with the ZS73 I get perfect stars from corner to corner so very impressed.


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