how does sgpro achromat compete against brevis's?

i've been a user of brevis and i've seen some CA aberration when using their achromat? is there anything better for brevis?

Yes, our optical flip array! The flip system transforms cameras like the XH-A1 into incredibly clean cameras and is certainly well regarded by our customers in terms of edge to edge sharpness too :-) Our video university series has a segment showing a test of the flipped Brevis with respect to CA...definitely some interesting results there.

Dennis i was thinking on getting a more bigger achromat (actually i don't know if they exist, i've havn't searched yet) since the midle is sharp, maybe i can have a bigger one and only use the middle, and then put a stepdown to 72 and use the cinevate spacer, do you think this can be achived that way?

Would the Canon 77mm 500D or 250D work? I actually have a 500D sitting in my drawer and will try it the next time I use my RedRock M2, but given that it has a fixed focal distance of 500mm (50cm or about 20") , it will need too much distance from the ground glass. The 250D may work with the rails provided.