--- ray/src/px/x11image.c	1993/04/29 12:17:45	2.25
+++ ray/src/px/x11image.c	1993/06/18 10:22:26	2.27
@@ -628,7 +628,7 @@ XKeyPressedEvent  *ekey;
 		if (avgbox(cval) == -1)
 			return(-1);
 		comp = com=='@'
-		? 59.2/pow(1.219+pow(luminance(cval)/exposure,.4),2.5)/exposure
+		? 106./pow(1.219+pow(luminance(cval)/exposure,.4),2.5)/exposure
 		: .5/bright(cval) ;
 		comp = log(comp)/.69315 - scale;
 		n = comp < 0 ? comp-.5 : comp+.5 ;	/* round */
@@ -652,6 +652,14 @@ XKeyPressedEvent  *ekey;
 		if (fast)
 			make_rpixmap(ourras, wind);
 		redraw(0, 0, width, height);
+		return(0);
+	case 'f':				/* turn on fast redraw */
+		fast = 1;
+		make_rpixmap(ourras, wind);
+		return(0);
+	case 'F':				/* turn off fast redraw */
+		fast = 0;
+		free_rpixmap(ourras);
 		return(0);
 	case '0':				/* recenter origin */
 		if (xoff == 0 & yoff == 0)