Check your footage interpretation in AE for field settings as well as the import and export settings in Avid. Also take care to figure out which color ranges you use. The Avid is quite picky and if you tell it to use the wrong ranges, it will of course wrongly normalize them. Rec 709 is different from RGB....
I'm not sure about the Interprete footage. Because my footage is in 23,98, After Effect doesn't have to analyse the 3:2 pulldown. The footage is in 23,98 in the interprete footage menu.
I don't realy know if what can interprete footage can do more for me...
What settings do you use exactly on all ends? this is critical, so please provide as much details as you can.
Export from Avid:
TIFF SEQUENCE 16 bit - Compression NONE, JPEG Quality 100%
1920x1080 at the projet frame rate: 23.976p
Color Space RGB
When reimporting that into Avid as is it works. No compression lost.
Import in AE:
Bring the sequence in a 1920x1080 23.976p comp
Pixel aspect square
Set the working space at 32 bits (float)
In interpret footage I<m using the Assume this frame rate and enter the 23,976 value.
The Separate fields option is at off (I<m in 23,976p)
In render setting:
Quality is at best, resolution full, field render at off, comp frame rate 23,976
In output module:
TIFF SEQUENCE, post render action at none.
Video output RGB, Depth millions of colors, color premultiplied
In the format TIFF option nothing is select (LZW compression, IBM PC ordering)
When reimporting in Avid:
Setting in RGB, Size for current workspace, Field ordered for curent format.