Thank you for the link to TIHA photograph and information in Vancouver, BC, Canada. Vancouver was my home port and college, where I obtained my Radio Officer's certificate.
I posted a comment on seatheships.org.uk website.

Here you can see her as "Tiha" http://www.seatheships.org.uk/gallery/showphoto.php/photo/117582/title/tiha/cat/503
Seems derrick 4 has been later modified.

On a closer look derricks 1,2,3 and 5 can only be used on one side. Not possible to swing to fwd or aft to cover 2 hatches. Only derrick N.4 can be used on 2 hatches. And that would be the "Stülcken design", the others are "just" swing derricks. Would be nice to see some more pics of this vessel

According to Lloyd's Register of Ships 1973-74, she has 5 derricks with 8 to. lifting capacity each.

I was not aware of different weight capacity for the derricks. The most I have seen them carry were large pallets of lumber for export, or a small front-end loader, placed in the ship's hold to unload cargo. It was difficult to determine the weight of the lumber, because different type of wood had different weights.
As Denis mentioned in the first post, why are Stuelcken derricks unique on this ship ?

Seems 4 out of 5 the derricks have a fairly light capacity of 20 mto about ( just a guess ) and consequently a higher speed. Only No.4 looks like a bit "heavier" 50-60 mto. But still an interressting design. Particular for swinging the derricks from fwd to aft and vice versa

During the 1960's I was the radio officer onboard Ivan Delmas, when she was named TIHA and I have numerous photographs of her in the Pacific, Asia, Caribbean and the USA. The ship was later sold to a French company in Germany and renamed Ivan Delmas. I would like to contact any crew member, or radio officer, including photographer Michel Thomas. My email address is : [email protected]
Name : faulkner

Wow, I've never seen a ship with FIVE Stuelcken derricks in a row... nor I thought there could be a reason for such to ever exist! What a unique ship, thanks for sharing!

Regards,
Denis