Chris, my response is for Tri-X Pan ISO 400. TXP is a different emulsion which I have not used. The Film Developing Cookbook by Stephen Anchell and Bill Troop (1998) have this to say about XTOL vs D-76. "Fine grain and sharpness are improved when compared to D-76 and T-Max developers. XTOL is now the developer most highly recommended by Kodak for T-Max films. It has been observed that dilution increases speed and sharpness with XTOL. Dilutions of 1:3 or more are frequently recommended. At these dilutions XTOL is effectively a nonsolvent developer, but because of its careful buffering, grain is still fine." They also mention that most films show about 10% more enlargeability. My experience squares with their advice. Xtol 1:3 is almost as sharp as Rodinal with less grain.(posted 8970 days ago)