this is sort of obvious, that besides sharing camera with an assistant,
family, friend or just passerby, even ourselves are culpable of
causing problems
if we look at the XP1's VF:
- its off center position in the top-left corner is quite advantageous: allows to shoot in RF style, and a nose is clear of LCD = no smears, no discomfort; provided that we focus with right eye;
- however, in VERTICAL orientation the only way to accomplish the same is to switch eyes - unless camera will be placed in a very awkward position, facing all up, with only point of contact being the right eye;
- there are very many photogs (myself included) whose eyes differ in the amount of correction required, and what is more this changes in time (even during a day, when fatigue and even levels of glucose in blood are all quite contributing factors);
so, gluing a screw-on diopter won't do at all as we'd need not one but
two of them - with constant screwing/unscrewing, and... lost shots

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