Use the same base 10 and cast it forcelessly, at least if you're talking about the Hermetic Arts. If not Hermetic Arts, who cares, steal the apprentice. 
Chris
With InVi spells, +1 magnitude gives some general information about what you are investigating (for instance, if investigating a spell, it gives Technique and Form) and +2 magnitude gives specific information (what the spell does and the sigil of the caster). I'm not sure which is the most appropriate here, but I believe one of the two should work.
Then just dont bother with official rules. Use the houserule i used, that you can use multiple R/D/T together and there´s no need for it. Just make sure you write down any new spells carefully so you dont mix up which R/D/T that applies what way.
I agree that Te/Fo shouldnt change just because of the number of targets.
It's more that "accidentally" detecting a magus would likely not be considered scrying (depending, of course, on the political situation at Tribunal). A magus disguised as a leg of lamb, would (normally) have a hard time explaining why that is something that other magi should expect.
However, I don't think that you can argue that a magus cannot pretend to be a leg of lamb in the pressence of other magi. Because if you can't be leg of lamb, then it seems that you also can't be a Bjornaer shapeshifted into a heartbeast of ram. Which sounds like an argument that would not go well at Tribunal.
I struggle with this one.
Totally OK that there is an InVi guideline for detecting the gift (can't recall teh supplement where it is called out, though). The problem lies in opening the Gift and determining what your InVi total needs to be to open it successfully.
Consider the case where a magus (a Quesitor) discovers, through some means, a Gifted child. If this child has, say, Second Sight and Entrancement -- which would be quite the find -- and they want to preserve both through the process of opening the Gift, one would need a fairly substantial InVi total, particularly if the child has an Ability score greater than 1 in each. In the rules mechanics, it is a simple calculation. However, what is the in-game, in-character means for them knowing whether they can successfully do it or need to contract someone from the lineage of Pralix (or how much they need to study)? Put another way, how does the magus know that they are good enough in the right areas to succeed, or do they need to experiment with all that attendant risk?
For myself, I would argue that this would require a fair amount of inVi work in the lab (and the core book does allow for this without explaining it) but if you want to make a story out of it, what do you do? Or, assuming you want to REALLY play it out, what series of InVi spells would be necessary?
-- Discover the Gift (and confirm it)
-- Determine other supernatural talents and thier extent
-- Determining whether your ability is sufficient to the task of opening the Gift in the manner you hope to
-- Developing a unique spell (or maybe not) or non-vis-using ritual that opens the Gift to the hermetic arts without damaging these NON-Hermetic supernatural talents
Now, suppose you determine that you lack the ability to preserve the Abilities. Is the "opening ritual/process" such that it allows you to choose how things change? The core book allows the magus to convert the non-hermetic Abilities into hermetic virtues (presumably related ones). In the example above, one could suppose that Second Sight could be converted to an Affinity with Intelligo (or possibly a minor magical focus in seeing spirits) and the Entrancement Ability into, say, Puissant Mentem.
Would this not imply that one should have some talent in MuVi since you are consciously manipulating the magic of the the apprentice? And how does this play against the apprentices Essential Nature? And why is the change permanent, when Mu spells can't be without being subordinate to a momentary Creo ritual? And, again, why does this not cost vis?
A standard Opening (if such a thing exists) could be explained by an Initiation Script that is protected very closely, perhaps more closely than knowledge of Parma, but since the Virtues conferred by a Script cannot be altered in most cases (There are a couple exemptions in the Bjornear write-up), this falls short of "converting" supernatural virtues into Hermetic ones and does not seem to answer the "preserving" supernatural virtues either.
I love a good mystery (yes, the pun is intended) but this one can go a lot deeper than is treated in 5th edition canon.
-K!
I think it is just a straight Magic Theory Ability Roll.
The magus needs to gather the right information somehow. InVi can detect the "level" of Supernatural Abilities. Alternatively, the magus can guess based on what the child can do (another Magic Theory, maybe Magic Lore Ability roll). Once he knows (or thinks he knows) what Supernatural Abilities the child has, it should then just be a straight Magic Theory Ability Roll to decide what the required magnitude of InVi Lab Total to Open the Gift is. The magus should know whether or not he can produce this magnitude of InVi Lab Total.
Personally, I would say it was also trivial information for somebody with Magic Theory to make this decision, and so not even require a roll (unless perhaps, the magus was really deficient in Magic Theory).
Ok, I am thinking that granting a normal sense would have the same range as the normal sense, where the "new" sense granted in Guidance on the Utmost Search has diameter of approximately 586 miles (based on the boundary definition selected at casting). "Mercia", "Wessex", etc., would be covered easily.
It would probably be cast in conjunction with Maintaining the Demanding Spell, if available at a sufficient level. Otherwise, the hunting magus would appear distracted a great deal of the time. Or, you could wait around and monitor candidates for a few days to see if they moved around. If they didn't, you could go investigate without having to worry about wasting your pawns of vis.
I hadn't thought of using two spells at once. That would substantially alter the way it worked.
The other mage was invisible or magically disguised? What? If the other mage is standing in plain sight around the corner, or even in front of you, you're still scrying on him or her should you use these spells; at least it appears that way to me.
Technically, yes.
However, it is only an issue if the other magus brings a case against you. And if you didn't know that they were a magus you could argue that it was "accidental". Which may (or may not) be an argument that carries any weight at Tribunal. Depends on the Tribunal and your saga.
I was not understanding what you wrote here. I re-read ArM5 p.114 up and down twice more and found nothing. I leafed through the spells and saw examples confirming your value, so it is now obvious to me that they are being considered as an ascending category group like the others. Honestly, I had thought all the sense "targets" were the same level: zero.
magical sense, p.113-114.
You want to see those with the gift, so you need target sight, equivalent of boundary (but doesn't need a ritual!)
I was thinking about just that. I'm a little bit away from confidently re-writing the rules yet.
I had thought that all the sense targets were level zero. Now I know better.
I am trying to re-write Guidance on the Utmost Search as only Intellego Vim, and then use a sense-enhancing spell to assist that.
ArM5 p.114 says that the equivalent of Smell is Group and p.113 mentions that is 10 people, so maybe I should say the spell can located up to 10 Gifted individuals whose Arts have not been opened. There is no suggestion in this case for how far away those people can be, which is somewhat frustrating. Can I even cover a village? What about London? I bet it smelled bad there. Would I need a third spell just for fine discrimination of odors?
If I add +5 Increased Size, that is 1,000,000 people.
What sort of spell would I design that would increase the range of a sense? It seems for Smell and Hearing I can increase the number, but not the range. I can't figure it out. (I can't even figure out what the game considers to be base mundane ranges for senses. The index does not assist in this case.) Do I have to go with +4 Vision (Boundary equivalent) because the other sense categories do not appear to work for what I am attempting to do?
It's higher-level than before, but it's not a ritual any more. Yay vis conservation!
Or I could do something like the below. Intellego Corpus doesn't seem right here to me because I not "perceiving a body", but rather allowing my eyes to see further than normal, but I don't know what else to use. Am I back to Muto Mentem, or maybe Muto Corpus since I am doing something to the eyes (Vision) and this is way beyond what is normally possible (and therefore it is not Creo)? If I go to Muto Corpus, can I still use a target of Vision to avoid Boundary? The guidelines of Muto Corpus do not seem suited for this purpose other than Base 2 "Change someone to give them a minor ability." Of course there is no definition of what that is.
I'm stumped. It seems the previous version above causes less swelling of the cranium for only 10 extra levels.
Also, these spells seem to be pretty high-level. A luxury Arch-Magi use to make finding apprentices easier? No wonder this type of spell isn't found on the standard lists.
No. It means "equivalent" only in the sense that Smell target and Group target both add +2 magnitudes to the spell level. How many things you can smell merely depends on their pungency and proximity to you (in the usual way).
Either Muto Corpus effects to alter your physiology (assuming you are Corpus), or Imaginem effects to collect the sense species in a different way.
Possibly, Mentem effects to change how you process the sense species collected by your senses (but that is probably not a very medieval perspective).
That puts me further in the dark than before since the game does not define what it considers those things to be.
Does the game need to define for you how smell works?
You are expected to use your everyday experience of how smell works. What is unclear for you?
Check the first page. I posted the guideline and two places to find it.
Chris
meow
As richard says.
The Smell Target means you target your sense of smell, and that this is as hard as targeting a Group.
So, if a spell makes the gift smell like strawberries, you could smell a potentially infinite number of people if near enough (imagine yourself in a strawberries field) or none, if there are none nearby (say, in the icelandic wastes).
What you then need is to be able to detect people from afar, which can be done with MuCo senses-enhancing spells, like giving you the smell of the bloodhound.
Here's a story seed, btw: With such a smell, you suddenly detect someone's gift miles away, whereas normal smell is much more limited (how far can you smell someone's perfume?). Who or what could have such a potent gift, that its smell alone could be detected across a countryside?
However, given of smell works and its limited range, you're, IMO, better of simply inventing a T: Vision spell, which allows you to detect by sight any gifted people (say, you see them as having a red aura).
For the record, level 60 is ritual anyway
But to me, just use your base 10 + 1 conc + 4 vision (final lvl 35). You can then use Eyes of the Eagle to gain a better sight, fly high, and look at the country for these little red dots.