http://www.filaposta.com/slania/portrait.php
It is a very good page.
There are quite good pictures, you can enlarge them.
I have a lot of his stamps. I had the opportunity to see also bigger work - breathtaking.
His friend told me that when he was already very old, around 80, being in the hospital, he had pieces of steel, a few gravers and a triplet loupe (in beautician!). He sat at the windowsill and worked...
I asked the man if he uses a microscope. He apparently never used!
He told me that while working in the left hand he held a loupe.
Supposed to transfer the project on the plate, in the company he worked for, they used photographic techniques.
But he also could do it without the aid - simply made a pre-sketching.