[acolyte99]

Take a look at the sentence just two sentences before the mention of the cover modifiers (page 183, emphasis mine):

The target resists physical spells with Body and mana spells with Willpower. If the target is also protected by Counterspelling (p. 185), she may add Counterspelling dice to this resistance test. This Opposing dice pool is further modified by any positive cover modifier the target might benefit from (see Defender/Target has Partial Coveror Good Cover,p. 160).

The general explanation how effect of any spell is determined tells us it is resisted by Body or by Willpower. Every spell is modified by any cover modifier.

Do you think, that they would have wrote this about the cover modifier just to mention something that is only meant for indirect combat spells.
Technically you are right, the words "Defense roll" is very unfortunate and in my opinion is a result of this being written in the combat section.
I personally have no problem with giving cover modifiers to all spells, because I can well imagine that it is easier to establish the mystic link to an "aura" whose owner I can see completely than to an aura whose owner I can only see a small part of.
If I can establish the link without problems caused by cover why am I having problems with visibility (which is stated for all spells on page 183 second paragraph of "choose targets").
In case of visibility there is no way out (like the use of "defense roll" in the case of cover) of this general description of "choosing targets" for all spells.

By the way: do you give cover modifier to targets that are surprised? 
Because by RAW they can't have one, because "Defender unaware of Attack" says there is no defense possible, so there is no defense roll, so no cover would count. 
I would think it's not as easy to shoot a target that I can see only a small part of than its full figure, but by RAW it would make no difference because cover is only used with Defense dice.

Edit: Just saw that Noble Drake posted while I wrote with similar arguments, but not exactly the same, so I will leave the post as it is.

[Eye Eternal]

First off, no not reducing the spellcasting pool, upping the defense pool yes. And the rules for attack cover is on pg 169, for ATTACKS which are not SPELLS attack spells or not, still a SPELL. And the fact that it covers spells later in the book, for their own things means use the rules for spells. And it states that cover does affect spells. You can't get a great link to them bc a wall partially obscures your view of them as a whole. LINE OF SIGHT partially blocked. So line of sight being the factor, you have negatives. It just the system so spells don't wreck you for having an exposed toe or little finger.

EDIT- I do consider cover for the unaware, but in THOSE cases I subtract from shooters pool and leave no dodge roll. When defending the defender can USE the cover, so it adds to them. In this specific case of unawareness, its the shooter compensating for the cover of their target.

[Redmercury]

So by the logic that cover makes it harder to perceive a mystic link for spellcasting, a astrally percieving mage should be able to ignore cover modifiers from a chest high wall (for example) unless the wall is covered in moss or other life.

[Noble Drake]

So by the logic that cover makes it harder to perceive a mystic link for spellcasting, a astrally percieving mage should be able to ignore cover modifiers from a chest high wall (for example) unless the wall is covered in moss or other life.

Just because the wall isn't alive doesn't mean it doesn't block vision in the astral just as well as in the real world.

Page 191 "Any non-living objects appear as faded semblances of their physical selves, gray and lifeless, while the auras of living things are vibrant and colorful."

A "gray and lifeless" wall is still a wall.

[acolyte99]

Regarding the wall in astral space: I don't see the difference. A material wall is not invisible in astral space. It blocks vision. It's a dark astral shadow. The only difference to a wall covered by moss is, that the "living" wall is that is glows in addition to blocking vision.
So both wall are not see-through and give cover.

Regarding the unaware defender, who by RAW is unable to have cover: I was just using this example to show that the wording of effects of cover with the unfortunate use of the words "defense roll" do not even make sense in the combat section.
Of course I can see how one can say "ok, since there is no defense roll, I will subtract from the shooter's pool", but it isn't RAW. By RAW cover would make no difference between a target with cover or without, because the wording with "defense roll" in the description of the cover modifier and this following literally by RAW doesn't sense here and in my opinion also not in case of direct combat spells.

By the way, for a shooter with only 3 dice it will be a great difference, if you ignore the words "defense pool" in case of an unaware target and just give the unaware target 4 dice for cover (the shooter can still hit the target) or if you substract 4 dice for cover (no roll possible without edge).

Edit: Ah, was again too slow to answer.

[Eye Eternal]

Well if you are only shooting with a 3 dice pool I would say you don't aim well enough to shoot someone who is half behind a wall. 3 dice pool is kind of a sad pool. Again wait for the person to expose a little kore only take the 2 for little cover. Or use edge like any other roll that is nearly impossible for the dicepool you have. 3 pool is like 1 agi 1 pistol and taking aim... Thats a sad shooter who wouldn't hit well without cover. Even if you say ok 2 agi 2 pistol a smartlink you got 2 dice past that cover. And that is an underskilled under attribute shooter... Taking aim before the shot gives you the extra 1, for 3 dice after mods. Even in poor light you have a positive pool still.

[acolyte99]

I know that one will probably never encounter somebody with only 3 dice. I was just demonstrating another illogical situation, if one tries to resolve the use of "defense roll" in the description of cover by subtracting instead of adding:

The 3 dice shooter cannot shoot the unaware target if you substract 4 dice for cover and the moment the target notices the attacker the shooter may shoot (because now the defender has a defense pool, RAW kicks in, the defense pool adds 4 dice and the shooter doesn't substract any more).

The wall and the position of the target and how much you can see of him has not changed and suddenly you can shoot him, because he became aware of being attacked. That's not good.
I would rather ignore the "defense roll" in cover and just give the unaware target the 4 dice for cover and thus have a consistent ruling, that changes logically if the target becomes aware of the situation.

If one uses this strict, literal wording in cover, you can also throw away visibility modifiers for spells.
Like this:
1. page 177 tells us Visibility Modifiers (page 136) are used in spellcasting in general.
2. Visibility Modifiers on page 136 are used for Perception tests and modify Perception dice
3. spellcasting is not a Perception test so I can ignore the table because it doesn't say at this page that it also modifies spellcasting

I know that this is of course not intended, but that's what I get, when I take stuff to literal.

I think the dev didn't have the space or didn't think of it to write in the cover section " modifies the defense roll or gives 4 dice that act like a defense roll exists  or adds to a resistance test if a spell was used"
But as it is, yes by RAW spellcasting ignores cover because of the "defense roll" wording and this wording causes illogical consequences even in the combat section itself.
I personally rather ignore this, but that's only a houserule.

[Eye Eternal]

Hmm, I considered the just give them 4 dice to defend thing. And I was totally on the fence about it. But you know that I have actually SAT and thought long about it. It is fairer to give the defender the cover dice. Gonna make that change asap.

[Orvich]

If I can only see someone's hand (the rest is under cover), does my stunbolt only effect that person's hand? That would be a reason for it to do less damage (lower spellcasting total), but is kinda goofy.

Similarly, you specify that it's not actually decreasing spellcasting rolls, but adding to the damage resistance roll. Why does that work, but armor does not?

That's what you trade for using a direct combat spell over an indirect combat roll. It doesn't always work, as breaking LOS will stop the spell from working. However, they get far less (besides LOS breaking) that defends against the spell. Indirect combat spells don't require LOS and can have all sorts of special effects and cost less base drain, but are easier to defend against otherwise.

Making it so that cover defends against direct combat spells when armor does not is the most illogical outcome, imo.

[All4BigGuns]

If I can only see someone's hand (the rest is under cover), does my stunbolt only effect that person's hand? That would be a reason for it to do less damage (lower spellcasting total), but is kinda goofy.

Similarly, you specify that it's not actually decreasing spellcasting rolls, but adding to the damage resistance roll. Why does that work, but armor does not?

That's what you trade for using a direct combat spell over an indirect combat roll. It doesn't always work, as breaking LOS will stop the spell from working. However, they get far less (besides LOS breaking) that defends against the spell. Indirect combat spells don't require LOS and can have all sorts of special effects and cost less base drain, but are easier to defend against otherwise.

Making it so that cover defends against direct combat spells when armor does not is the most illogical outcome, imo.

All or nothing. If you can see ANY part of them, you can target and affect them, by the same token, if you can't see them, you can still throw that Fireball or Ball Lightning over there to frag the crap outta them.

[Orvich]

Exactly! Anything but perfect cover is irrelevant to a direct combat spell, and this makes perfect sense.

[All4BigGuns]

Exactly! Anything but perfect cover is irrelevant to a direct combat spell, and this makes perfect sense.

Yep, and like I said, even with the "perfect" cover, that Fireball will still frag 'em.

[Glyph]

Page 173, SR4:
"Visibility modifiers (including darkness, cover, and other impediments) noted for ranged combat also reduce the magician's Magic + Spellcasting pool when casting spells."

It's pretty clear and unambiguous.  Mages already don't have to worry about recoil, movement penalties, or range.  If you are letting them ignore visibility penalties too, then it's no wonder you think they are overpowered.

[Orvich]

Not seeing that line in SR4A anywhere. It mentions all over the place that Visibility modifiers may be applicable to a spellcasting roll, and/or an "and/or" phrase, which accomplishes much the same message that they sometimes are a factor.

[Noble Drake]

Not seeing that line in SR4A anywhere.

That line is, as was labelled, a quote from SR4 - the closest I can find in SR4A (2012 printing PDF) is this:

page 160, Defender/Target Has Partial Cover, last sentence "Note that this modifier applies to all Ranged Combat tests and also to Spellcasting using line of sight."

page 160, Defender/Target Has Good Cover, last sentence of first paragraph "This modifier too is applicable to both Ranged Combat and Spellcasting."

This whole idea that having LOS to only part of the body (say just his head peaking over a car) means spells get 100% targeting potential is insane - why would I not also get that same benefit trying to shoot that guy in the head? My target is only his head, and I can see that, so no cover... right?

Wrong - cover applies, the book says so a dozen times.