diff --git a/scripts/imgtool/main.py b/scripts/imgtool/main.py
index 1917a97..a03a164 100755
--- a/scripts/imgtool/main.py
+++ b/scripts/imgtool/main.py
@@ -142,15 +142,16 @@
 @click.option('--align', type=click.Choice(['1', '2', '4', '8']),
               required=True)
 @click.option('-k', '--key', metavar='filename')
-@click.command(help='Create a signed or unsigned image')
+@click.command(help='''Create a signed or unsigned image\n
+               INFILE and OUTFILE are parsed as Intel HEX if the params have
+               .hex extension, othewise binary format is used''')
 def sign(key, align, version, header_size, pad_header, slot_size, pad,
          max_sectors, overwrite_only, endian, encrypt, infile, outfile):
-    img = image.Image.load(infile, version=decode_version(version),
-                           header_size=header_size, pad_header=pad_header,
-                           pad=pad, align=int(align), slot_size=slot_size,
-                           max_sectors=max_sectors,
-                           overwrite_only=overwrite_only,
-                           endian=endian)
+    img = image.Image(version=decode_version(version), header_size=header_size,
+                      pad_header=pad_header, pad=pad, align=int(align),
+                      slot_size=slot_size, max_sectors=max_sectors,
+                      overwrite_only=overwrite_only, endian=endian)
+    img.load(infile)
     key = load_key(key) if key else None
     enckey = load_key(encrypt) if encrypt else None
     if enckey:
@@ -159,10 +160,6 @@
         if key and not isinstance(key, (keys.RSA2048, keys.RSA2048Public)):
             raise Exception("Encryption with sign only available with RSA")
     img.create(key, enckey)
-
-    if pad:
-        img.pad_to(slot_size)
-
     img.save(outfile)