How long does an arty 'spot' last?

[-Svea-Livgarde-]

...until you are dead or for a certain time?

[Dukat]

Good question.

I think once you've spotted and stay alive, it lasts about 90 seconds.
If you die, it will last as long as your kit stays on the ground. Maybe even an additional 15 seconds longer. However it is similar to the time it takes for mines to vanish.

If somebody picks up your kit after you died and keeps using it, it will stay for a max of 90 seconds.

I don't know exactly, these are just estimated values.

[Capten_C]

My guess is about 30 secs after you've respawned. (I've usually started spotting again by then anyway!) 

[RN_Max]

I think the view also lasts until the same spotter targets something else in less than 90 seconds.

I had an infuriating round last week with a couple of spot hoppers who couldn't keep focus on a valid target and weren't accurate with the binoculars... I saw rivers, open fields, random static objects, empty terrain where mobile targets had moved, even what looked like an off-map glitch.

Its at times like these the ability to cancel the damn spots would be handy, as 90 seconds of multiple crap targets is such a chore to switch through.

[Dukat]

If you're spotting, try to stay alive. Just consider: The spot takes a moment until it arrives at the artillery operator. Then the operator needs to check whether the spot is valid. By then, 5 to 10 seconds have passed. Then the operator puts the dials on zero. He right clicks again, to watch his first shot. Most likely he has to adjust the dials again. Until then about 30 seconds may have passed. If you die shortly after having spotted, you spot disappears after about 30 seconds. So that doesn't help the arti operator at all, when he is about getting close to hit his target. Operators also concentrate on spots that stay for a long time.

When multiple spotters are spotting, the latest spot is being shown to the artillery operator, switching forward from the previous spot. But when the operator was about hitting the previous target, he will switch back to the previous spot. If many spotters spam spots to the artillery operators or repeat their spot once within ten seconds, the operator will have his hands full finding the spot he was targeting. He won't be able to concentrate on his task any longer, switching between the spots to find the one he was using. It is like in the saying: Too many cooks spoil the brooth. To many spotters cause the arti to not work properly at all.

Best is to spot for arti, when it is asking for a spot. If others have already spotted targets, you should abstain from spotting another one. You also have to consider the amount of arti available. If there are about 3 artilleries operational, it is ok to have 3 spotters spotting different spots. But 3 spotters for one arti is too much, especially when the spots are spammed repeatedly or being adjusted in case of a moving target.

In general you should not spot moving targets. The arti operator won't be able to adjust the gun as fast as the target is moving. Especially tanks make it more difficult for the arti operator to hit anything as he has to switch ammo on top. Rather spot a chokepoint where waves of enemy infantry is moving through to the frontline. If the arti operator misses the first wave of infantry moving through the chokepoint, he'll do much better when the next wave comes. This shows however how important it is to provide long lasting spots by staying alive.