ZWO 1.25″ Atmospheric Dispersion Corrector / ADC
ZWO 1.25″ Atmospheric Dispersion Corrector / ADCZWO 1.25″ Atmospheric Dispersion Corrector / ADCZWO 1.25″ Atmospheric Dispersion Corrector / ADC

ZWO 1.25″ Atmospheric Dispersion Corrector / ADC

  (6 Reviews)
✓ 2 year warranty


3x in stock shipped 1-2 working days

Dave says

"Tuning the ZWO ADC improves the view for visual observation and when imaging at high magnifications.

My images of Saturn, which is low in our sky so more affected by atmospheric dispersion, are noticeably crisper and sharper."

About this product

Model:  zwo_adc
Part Number:  ZWO-ADC

Latest version with bubble level to aid zero position alignment

The ZWO Atmospheric Dispersion Corrector (ADC) is the first of it's kind, designed and manufactured by astronomers for astronomers.

Significantly reduces the prismatic smearing (atmospheric dispersion) caused by light passing through moisture in our atmosphere, a common problem encountered when observing/imaging planets at low altitudes.  

The aberration is viewed as false colour then corrected via the positioning of two high quality 1/10 Lambda surface quality prisms, resulting in views and images of planets with noticeably improved surface detail.  

Note: For best results position the ZWO ADC immediately before the eyepiece and place other optical accessories (barlow, diagonal, etc) in front of the ADC (telescope side).  I.e. eyepiece -> ADC -> barlow -> diagonal -> telescope. 


  • Threads: T2 Male and Female
  • Optics: 2 Prisms
  • Material: H-K9L(Schott BK7)
  • Surface Accuracy: λ/10@632.8nm
  • Deviation Angle: 2°
  • UV friendly Anti-reflective (AR) Coating
  • ADC Body Height: Approximately 30mm

UV Friendly AR Coating

Customer reviews

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

Rating (max 5):  
07 January 2023  | 

FLO never disappoint, we've had quite a few items from them and they always keep us up to date with the orders, very polite and helpful, highly recommended 👌😁

Rating (max 5):  
Exceeds expectations
12 September 2022  | 

For anyone that spends any time observing or imaging the planets in our turbulent UK weather, we know that seeing is seldom good.
I bought this on a whim not expecting much but WOW!! The first time I used it I had not expected much of a visual change but the enhancement to the views is like night and day.
I moved onto imaging the planets with this and I could never be without an ADC anymore. This is an essential item.

Rating (max 5):  
very good product
07 March 2019  | 

very good product

Rating (max 5):  
11 June 2018  | 

The only way to get sharp images of the planets visual and for planetary imaging.

Rating (max 5):  
Rescue Your Planets
08 June 2018  | 

This little gem works wonders. This year (2018) when planets are all very low it has let me get better images than the previous year.

I must admit that I have struggled to get an approach to setting it that works better than trial and error. Set the ADC to the neutral position (arms together) and get a view of the planet that is greatly over-exposed, this typically blurs so it shows blue and orange edges. Align the ADC arms with the direction of the blur, then open them out until the coloured edges disappear. If they get worse, rotate the ADC 180 degrees and try again.

The effect is quite dramatic, but adjustment is not hyper-critical as the view/image just gets better and better as you get close to the correct position and even a bit under or over corrected will be vastly better than no ADC at all.

When you go to a normally exposed image, you will see it is much sharper than without the ADC. I'm sure it will work well for visual use as well.

Here's a link to an image using the adc:

Rating (max 5):  
ZWO 1.25 ADC
07 February 2018  | 

Another very well made product from ZWO. Yes, there are more expensive versions on the market but for the specific use I require this for this offering from ZWO is perfect. I have not yet managed to get any images through this due to very poor conditions however visually this does greatly make a difference. No instructions with product but they can be found on the internet as can video demonstrations.


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