The postman brought me a 300mm m10 threaded rod counterweight bar today, but unfortunately I am still not happy (I know, not easy to be...): the mini pentax alt/az mount I intended to use as a DEC unit adds way too much moment arm and my 2.8/300 nikkor + camera needs a whopping 2kgs of counterweight to balance! and it indeed makes the mount slipping if I add less. Back to square one: ball heads...
I had a medium sized stronger one, just broke recently. A small one that can hold the gear for a minute verified that the mount doesn't slip when i use it (far shorter moment arm).
Also, there is this nice example with a gimbal head: https://clarkvision.com/articles/astrophotography-tracking.mounts/
Also, there are geared heads with the footprint of a large ball head with fine adjustment - costing an arm, leg and half a kidney! https://www.aliexpress.com/item/1005006442147941.html
I really love the idea of a geared head, but it is simply uneconomical to add one to this kit, even a cheap one would bring the total mount cost to the level of a second hand GEM28. I am deciding between the large ball and the gimbal, both I'll be able to use for terrestrial photography.
I had a medium sized stronger one, just broke recently. A small one that can hold the gear for a minute verified that the mount doesn't slip when i use it (far shorter moment arm).
Also, there is this nice example with a gimbal head: https://clarkvision.com/articles/astrophotography-tracking.mounts/
Also, there are geared heads with the footprint of a large ball head with fine adjustment - costing an arm, leg and half a kidney! https://www.aliexpress.com/item/1005006442147941.html
I really love the idea of a geared head, but it is simply uneconomical to add one to this kit, even a cheap one would bring the total mount cost to the level of a second hand GEM28. I am deciding between the large ball and the gimbal, both I'll be able to use for terrestrial photography.