diff --git a/libvips/foreign/tiff2vips.c b/libvips/foreign/tiff2vips.c
index 760a5d11..245f9807 100644
--- a/libvips/foreign/tiff2vips.c
+++ b/libvips/foreign/tiff2vips.c
@@ -754,15 +754,13 @@ rtiff_labpack_line( Rtiff *rtiff, VipsPel *q, VipsPel *p, int n, void *dummy )
 {
 	int samples_per_pixel = rtiff->header.samples_per_pixel;
 
-	float pf[3];
 	int x;
 
 	for( x = 0; x < n; x++ ) {
-		pf[0] = p[0] * 100.0f / 255.0f;
-		pf[1] = (signed char)p[1];
-		pf[2] = (signed char)p[2];
-
-		vips__Lab2LabQ_vec(q, pf, 1);
+		q[0] = p[0];
+		q[1] = p[1];
+		q[2] = p[2];
+		q[3] = 0;
 
 		q += 4;
 		p += samples_per_pixel;