ZWO Atmospheric dispersion corrector question.

[wavydavy]

Will an ADC work with a mono camera, and improve the seeing/image, or is it purely for visual or colour cameras??

[Kokatha man]

"Yes" - contrary to what some think the effects of atmospheric dispersion are not just the shifting of the colour channels in an image. if it were then a simple channel alignment application in Registax6 etc would solve the problem!

There is "dispersion" within each channel such that the quality of each in an image is affected to the detriment of resolution (think of it as a kind of "blurring" of the details)...a Wratten #47 filter can be used to set it with a mono camera but all of our Mars images this year here https://stargazerslounge.com/topic/364851-35-days-of-mars/   where the planet was mostly around 49°-50° used an ADC & a mono camera.

Fortunately for us we have both the ASI462MC (colour) & ASI290MM (mono) cameras which each have similar pixel-sizing in the sensors & are thus parfocal, so we could set the ADC with the colour cam & then swap in the mono cam for our imaging captures.

Pretty soon we realised the lever separation of the ADC was a constant amount of 1 gradation either side of the slip ring over the period from about 1.5-2 hours before & after culmination of this planet...so we did not need to use the colour camera at all after the first few trials...merely setting the levers at that separation with the centre-reference horizontal on our C14 at the start using only the mono camera...& re-adjusting every 15 minutes to keep the centre-reference horizontal via its bubble level & re-adjusting the levers either side of it to maintain that 1 gradation separation.

Edited January 10, 2021 by Kokatha man

[wornish]

I would love to get an ZWO ADC but they seem to be out of stock across Europe.

[matt_baker]

Someone's selling one on a Facebook group if you have it

[Pete Presland]

Excellent detailed response by @Kokatha man