Opportunity Fire Control

[Corto2London]

Hi mates, 
Just wonder how experienced players adjust their Opportunity Fire. 
Do they let it as default settings ? 
Do they change them ? 
Do they change them once for all or do they adjust them according to scenario type (Kursk open places, Normandy boccage...) ? 
Thanks for your opinion.

[ComradeP]

That depends on the scenario, or the task you have in mind for a unit.

In scenarios with difficult terrain, it might be helpful to keep your men and equipment concealed for as long as possible as the defender.

However, firing from close range also means the enemy fires from close range, which can make firing from range 1 worse for you than for the attacker if the attacker has more units or units with better quality and SA values.

Example: Guards Rifle units not in bunkers can't really deal with any kind of Panzergrenadier formation, as those will in most cases have an adjusted SA of 18.

Setting spotters to never fire will make them less likely to be discovered, particularly if you place them in a position where they can still see numerous hexes but are unlikely to be recon-spotted soon.

Units in ambush positions should either have opportunity fire set to off or not based on if they can and should start firing as soon as an enemy unit approaches. An example of this would be units in a town or forest, where the likely range of engagement is 1 hex. Do keep a close eye on elevation differences, to make sure they can actually only be engaged from the hexes you think they can be engaged from. The visible hexes function helps verify that.

[Corto2London]

That depends on the scenario, or the task you have in mind for a unit.

In scenarios with difficult terrain, it might be helpful to keep your men and equipment concealed for as long as possible as the defender.

However, firing from close range also means the enemy fires from close range, which can make firing from range 1 worse for you than for the attacker if the attacker has more units or units with better quality and SA values.

Example: Guards Rifle units not in bunkers can't really deal with any kind of Panzergrenadier formation, as those will in most cases have an adjusted SA of 18.

Setting spotters to never fire will make them less likely to be discovered, particularly if you place them in a position where they can still see numerous hexes but are unlikely to be recon-spotted soon.

Units in ambush positions should either have opportunity fire set to off or not based on if they can and should start firing as soon as an enemy unit approaches. An example of this would be units in a town or forest, where the likely range of engagement is 1 hex. Do keep a close eye on elevation differences, to make sure they can actually only be engaged from the hexes you think they can be engaged from. The visible hexes function helps verify that.

OK, thanks a lot for your kind and long answer. 
But does it mean you adjust a particular Opportunity Fire depending of scenario, but you also adjust it in a game, depending of evolution of events ?

[ComradeP]

I might adjust it at the start of the scenario for every unit category through the global opportunity fire settings, or only for units where I feel it's necessary at that point.

One important thing to keep in mind is that units will only stick to the opportunity fire settings when they think they haven't been spotted. Opportunity fire settings won't have any effect in non-cover terrain (note that terrain that functions as cover for infantry and guns won't necessarily cover vehicles, vehicles need at least a terrain height of 2 meters which can be checked per terrain type in the parameter data dialog).

As the battle is dynamic, opportunity fire selections might need changes on a turn by turn basis. For example: you might move your men into some woods, and knowing that they can't be assaulted by anybody moving into the woods after them, you might want to change opportunity fire. You might want to set the units to fire if you feel it is to your advantage, or you might want them to stay hidden so the enemy doesn't know where your units are.

There are some other things to keep in mind when you plan effective use of opportunity fire:

-The enemy can still detect if a hidden unit is in a hex by trying to move into the hex. Either an assault will be planned, or a notification will appear stating that there are not enough movement points remaining for an assault.

-Hidden units have no ZOC, so they might suddenly find themselves being isolated (or ideally they will isolate the enemy on their next turn, but if the enemy isolates itself they won't need to pass a supply check and be isolated until their next turn I believe). Come to think of it, I'm not sure if units detected through the above process will suddenly have a ZOC, never tried that.

[Corto2London]

Thank you very much for sharing all this knowledge, I will start working on all those stuffs.
At the moment I play everyday and progress regulary but I didn't experiment at all these Opportunity Fire tune. I will.
Thanks mate, and maybe one day I'll ask you for a small PBEM  ;- )

[Dog Soldier]

Simple rule for hidden units. While hidden, no ZOC. Once revealed to the enemy the ZOC is in force. How the hidden unit is revealed, does not matter.

Dog Soldier

[ComradeP]

But if you cancel the movement-turned-into-assault action and the defender doesn't use opportunity fire, the defender isn't revealed I believe.