"I looked more calmly through the 12 × 42 with support than through a 10 × 42 without support."
If the Head Rest makes a 12x more stable than 10x without it that is a huge improvement. Almost like IS in my opinion.
The headrest improvement gets better every time you mention it. Your original comment was that " The Head Rest works amazingly well" which has now morphed into "Almost like IS in my opinion". Oh, can l just ask if in order to justify these statement have you looked through an NL with a Head Rest attached.
Again, like the original author, you are making statements that have no basis from which to judge what you say is correct. IS l assume is image stabilization but that can be described in various forms :-
1. The binocular just held by the arms is the worst form of stabilization and can be considered as a base on which to gauge improvements.
2. The binocular held by the arms and pressed into the glasses, eye sockets or eyebrows.
3. The binocular held by the arms and the hand holding a cap or splayed to the head.
4=. The binocular placed on a finn stick/monopod which is supported by the arms
4=. The binocular held by the arms and with an outrigger head rest to the forehead as per the NL. (Presumed)
6. The binocular held by the arms and fitted with an image stabilization system comprising electronic/mechanical operation. The arms only support the weight of binocular and don't provide much stabilisation.
7. The binocular mounted on a heavy tripod where the arms provide no stabilization.
These are all methods of increasing the stability of the image from the weakest no.1 through to the total stability of no.7. Which one do you mean in your statement and how can you justify it when the original author never mentioned IS?
Stan