Sensing appears as a passive ability from what we seen with Karin and others. The only time it seems to require concentration is locating specific people And as far as we know, being tired/injured shouldn't matter and it doesn't cost much.
Karin has sense people numerous times without being aware of a need to sense them. Naruto too has sense people without knowing to look for them.
I think that's more about the sheer strength of Hashirama's chakra, same way Sasuke and co all sensed Naruto's chakra despite not being sensors.
That has never been mentioned in the manga otherwise Rikudou King and I would not be having a discussion or debate. I was wondering if Madara could sense because he was able to react to Raikage without shock at him appearing out of nowhere.
Probably because they weren't trying to hide their chakra or were actively sensing?
Ah Thanx, i thought i missed some thing
That is may be just like when once a hound learns some scent it recognises whenever it comes in his smelling radius.
Nagato too was able to sense Kabuto's chakra if I recall right, and Itachi said it was Nagato's ability, so I suppose the Rinnegan can grant you this ability
Well hiding one's chakra shouldn't mean an ability is active, they weren't in a situation where they would have been purposely sensing.
Which would suggest their abilities are passive, as mentioned before.
Or his Uzumaki blood, considering Miko and Karin. Neither Obito or Madara have showed similar sensoring, nor did the Paths, despite all having the Rinnegan.
That's what I was saying though. The ability is always on normally, without the user having to willingly employ it except to find specific targets. Madara was never shown sensing anyone but Hashirama and that seems more due to it being Hashirama then due to an ability.
