The photo shown in the MCA post are taken by Pentax K100D with Meyer Lydith 30/3.5 which has a 42mm thread mount, often known as M42 mount. It has 5 elements in 5 groups, and minimum focusing distance is 0.33 meter or 1.1 feet. It is believed to be a simplified design of his brother Meyer 29/2.8. From my own knowledge, there are three versions in the production line of East German 30mm series, both share the same design but in two different names, Meyer and Pentacon.
It all starts when I picked up a booklet at a small cafe in Paddington...I thought Bruce might be interested in this kind of stuff, or say basically ARTS, lolz, so I asked him whether he wants to check out the exhibition on Wednesday.
It was raining heavily in the morning but turned into a beautiful sunny day when we were ready to roll, lucky tho. We had a late lunch at the highly rated sushi bar, and walked all the way to MCA.