Ted Ramasola
Veteran
in my experience, bigger achromat lens doesnt necessarily mean better. Case in point was an indian made ASIAN brand 72mm achromat, terrible CA and soft corners and edges.
Next was the first gen 72mm Cinevate which was similar to the first gen redrock. Better than the Asian but still had considerable CA at the sides.
What worked in my set up was the SG pro achromat, while housed in a 72mm ring and thread, the actual optics was much smaller, probably 55mm only.
So I would say its not the achromat size but quality of the glass and its magnifying power.
Next was the first gen 72mm Cinevate which was similar to the first gen redrock. Better than the Asian but still had considerable CA at the sides.
What worked in my set up was the SG pro achromat, while housed in a 72mm ring and thread, the actual optics was much smaller, probably 55mm only.
So I would say its not the achromat size but quality of the glass and its magnifying power.