YouTube
The Fudō Bīja hāmmāṃ
The Mahāvairocana Seed Syllable vāṃḥ
Note here that the calligrapher makes an error. He writes ba instead of va. The two are very similar. In ba the curve curls back to meet the stem on the up-stroke, whereas on the va it continues down to the stem on the down-stroke. These letters are similar in most Indic scripts: cf Devanāgarī ब व. Indeed they are often confused in pronunciation as well.
Labels: calligraphy, Siddham, YouTube