diff --git a/progs/osdemos/ostest1.c b/progs/osdemos/ostest1.c
index 2c7adfc..000b8c4 100644
--- a/progs/osdemos/ostest1.c
+++ b/progs/osdemos/ostest1.c
@@ -407,7 +407,10 @@
    glGetIntegerv(GL_ALPHA_BITS, &cBits);
    assert(cBits == bits);
 
-   printf("Rendering %d bit/channel image: %s\n", bits, filename);
+   if (WriteFiles)
+      printf("Rendering %d bit/channel image: %s\n", bits, filename);
+   else
+      printf("Rendering %d bit/channel image\n", bits);
 
    OSMesaColorClamp(GL_TRUE);
 
@@ -458,6 +461,8 @@
 {
    int i;
 
+   printf("Use -f to write image files\n");
+
    for (i = 1; i < argc; i++) {
       if (strcmp(argv[i], "-f") == 0)
          WriteFiles = GL_TRUE;