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Does anyone know anything about the formulas or algorithms used to determine the potion effect strength and duration, the chance of successfully brewing a potion, determining which multiple fortify/drain/restore attribute effect gets selected without the MCP fix, or the potion weight in vanilla?

I've contacted Hrnchamd over at the BethSoft forums, but so far I haven't received any replies yet.

Shameless plug:
I want to add such information to my Potion Maker, and I'd be extremely grateful for any facts or tips.

I think this ingredient combo is a bit easier to acquire. Nice potion, though. My future Argonian water hunter will need something like that.

I see the sharing feature would be useful with this tool as well.

I know it has to do with both intelligence and alchemy skill level. For a long time I made super potions using fortify skill and then I met someone online that did it with his alchemy skill. I did not believe him till I tried it myself. You can make very expensive, very light weight, very long lasting, and powerful potions. Originally I thought the alchemy skill just make it more likely to successfully make one but it effect how powerful they are too. No idea of the formula

Edit: oops I meant fortify intelligence not fortify skill.

Thanks everyone.

I've contacted Zoopster despite his last activity being in 2009. In one of his quotes in the FAQ he mentions some numbers, but those might have been empirical testing only. Hopefully he replies and can help me, thanks for the pointer.

Otherwise, the only thing I can do is do some testing when I find some free time for that, crunch the numbers and try to figure out the formulas myself. Time to remember some of that uni math...

hey guys - i know it's been a while since anyone posted on this thread, and as there seems to be no resolution (I would *love* to see the full results in the Potion Maker!) i decided to go tinker with it myself to find out, and after some preliminary work, i've got some things to add

Some observations:
A (very) basic formula for alchemy results goes something like this: (when alchemy, luck, and intelligence are all equal)
-Firstly, PS is potion strength, PD is potion duration, ALT is value of alchemy, luck, and intelligence, BC is base cost of effect, and MQ is quality of mortar & pestle
-PS = MQ * ALT * .4 / BC
-PD is *always* 3 times PS (sometimes the numbers don't line up exactly, there are decimal points that are unseen)

As far as differing values for Alchemy, Luck, and Intelligence, I haven't gotten that far (all the work so far was hurting my head!), but I can say this so far:
-Intelligence and Luck seem to have the same effect on potion quality (I know, it's controversial, but I've tested it - bear in mind, this is all preliminaries, but it seems that way at this point) - in my testing, halving my luck dropped about 5% off of the potion quality, and the same was with intelligence - BUT - halving my alchemy dropped about 45% off of the quality, so I'm thinking maybe the (luck * .125) in other formulas (like spellcasting, i think) may apply here as well, along with intelligence

On alchemy equipment:
-For positive effects, the Mortar & Pestle is the only one that uses a multiplier (that being its quality)
-Calcinators and Retorts *add* to both strength and duration, and both add the same amount - see below
--Apprentice - adds 1 PS and 1 PD with either/or, and 2 with both
--Journeyman - adds 1 PS and 1 PD with either/or, and 3 with both
--Master - adds 1 PS and 1 PD with either/or, and 4 with both
--Grandmaster - adds 2 PS and 2 PD with either/or, and 5 with both
--*Secretmaster - adds 3 PS and 3 PD with either/or, and 6 with both
--so, the higher your alchemy/intelligence/luck, the less useful Calcinators and Retorts are
--and, the higher the BC, the more useful they are
-Alembics, everyone knows they only help with negative effects (at least everyone who has read the alchemy page) - they will drastically cut the strength and duration, as follows:
--Apprentice - reduces PS and PD by 33%
--Journeyman - reduces PS and PD by 50%
--Master - reduces PS and PD by *about* 55%
--Grandmaster - reduces PS and PD by 60%
--*Secretmaster - reduces PS and PD by 66%
-Tried figuring the formula based off of the qualities, but like I said, my head hurts - if someone else beats me to it, have at it, otherwise i'll prob do more work on it tomorrow evening

-Lastly, for some strange reason, Invisibility didn't act as predicted - the duration was actually shorter when using both calcinator and retort than when using either/or (don't believe me, try it - 100 ALT and GM equipment yielded a 12 sec potion with both, and an 18 sec potion with either/or) - I'm not sure why this is, maybe something to do with the lack of magnitude (i'll test this later with water walking/breathing, and paralysis) - just very puzzling

I think that's it for now, I'll work on it some more tomorrow evening and post my findings then - if anyone has anything to add that would be helpful, I'd love the assistance


EDIT: The formula for how much the PS & PD is reduced by the Alembic is...(AQ is alembic quality)
1/10 + (8 * (AQ) / 15) - (2 * (AQ)^2 / 15)

This is final - took looking up math skills I'd forgotten I used to know how to use!
Will be posting more soon, hopefully can have a complete formula before long!

*excited!*

Wow. This is some serious dedication to alchemy right there.

I suppose this means I should at least make the potion maker completely functional again. I took the quick (and heavy-handed) approach to take out the ingredient adding links thanks to Googlebot and just removed them. They should be back for users with JavaScript, but that's far down the TODO list at the moment. I will move it up.

And for the sake of completeness, Zoopster wrote me back. Unfortunately, he never had any complete formulae for alchemy, so I think your work, DextroWombat, might be the most detailed so far. Good job, and I look forward to the complete formula to put in!

I have it! The master alchemy formula! (it's ugly, fair warning)

First, the variables:
A -> Alchemy
L -> Luck
I -> Intelligence
MQ -> Mortar & Pestle Quality
AQ -> Alembic Quality
CQ -> Calcinator Quality, rounded
RQ -> Retort Quality, rounded
BC -> Base Cost (of spell effect)
C -> Calcinator used (1 if yes, 0 if no)
PS -> Potion Strength
PD -> Potion Duration

So, we've got 2 different equations, 1 for positive effects, 1 for negative:

PD (Pos) = MQ * (A/BC + L/10BC + I/10BC) + (C+1)(RQ) + CQ
PD (Neg) = MQ * (A/BC + L/10BC + I/10BC) * (-2/15 AQ^2 + 8/15 AQ + 1/10)
EDIT: This is garbage: (-If calcinator is used, plug in PD (Neg) to Tot below:
(--PD (Neg) = (29 Tot^2 + 197Tot/48 + 60) / 120

And there we have it! PS = PD / 3, always

Still some work left to do with the Invisibility thing, as well as figuring out what effects follow whatever special rule it's using

That takes a lot of dedication and work, I applaud you. Excellent work you got there!

thanks AtoM! posting it to the wiki as we speak...

Edit: oop, not done after all - got the calcinator thing wrong, gimme a few...
works with a journeyman alembic, not sure if it scales right

It's a bit complex for me, maybe I could help, but I'm not sure how.

think the only problem i'm really having is the relationship between the alembic and the calcinator
the calcinator is *supposed* to increase negs, but mixed with an alembic, it decrease them further
can't seem to find the exact relationship, though - that formula i typed under the alembic part up there is garbage

you know anything about functions with 2 variables?

How did you get the formula?

I was hoping to make a big spreadsheet with all 10 variables and two result values, then finding a nice formula that fit. The simpler, the better, but it would have to fit the samples exactly (with rounding or truncating, of course). I hoped to employ some free math tool I could find (probably something we used at uni, Matlab or Mathematica or whatever it was).

well, yogi, to be honest, i sat up all night tweaking on it and had to relearn Calculus!

basically, i just made some *huge* lists of sample data (i mean huge, my bedroom is a mess right now - think I went through like 2 1/2 notebooks!) and went about the long, arduous process of compiling it all into one big formula

actually using excel right now to do all the thinkin, cuz i'm super tired now and the dope's all gone, so i'm runnin on nothing but fumes, but i'm damn determined to get this done tonight! it's coming in pretty handy finding patterns and such (spent 2 hours re-learning derivatives, for christ's sake!)

i wish i hadn't stumbled on that thing with the Calcinator/Alembic combo - it's killing me! everything else is done, but this thing is some kind of exponential or cubic or something crazy and i'm not having too much luck - 3 times last night (after about 2 hours between!) i thought i had it, but checking it and it ended up not working - not feelin too bad about it cuz it's a big ugly nasty equation, i'm kinda pleased with myself that i can actually still do this stuff, but it is pretty frustrating (and my finger hurts!)

as far as the formula goes, i'll go into more detail on that when i post my completed work on the wiki!
and i was planning on making a little spreadsheet thing as well, seein as how i got a head start on you, do you want me to send you a copy when it's done? probably need a hand workin the kinks out of it anyways, and it'd be great to get another brain involved that knows what's going on (asked my GF for help, but she wasn't much...don't tell her i said that :p)

so yeah, that's all for now, still working on the damn Alemnacalcequation (again, i think i'm on try 6 now)

oh - if you've got a chance to do some work on it, i still don't know what's up with that invisibility thing (haven't got to it yet, it was of secondary importance to the grand formula, but it does need to get in there somewhere) - also, haven't started on prices yet - it doesn't seem to involve any tools except the mortar, so it should be a fairly simple equation (yeah, right!), i do know that alembic and calcinator don't figure into it, so i'd assume retort won't either, so it'd be based off of Alch, Int, Luck, MQ, and Base Cost

and might need help making the formulas prettier - it works great for programming, but the average person will see that and not care to ever use it (especially when i get this last piece in)

k, signing off - thanks for the interest and encouragement, and the great project idea!


--------------------UPDATE-------------------------------

Been doing some more work and found that the formula for the alembic multiplier was actually even simpler: 1/(AQ + 1)
Still haven't found how the calcinator fits into that, and really not making much progress - if there are any math heads out there, or you know someone that's really good at calculus-type stuff (mebbe someone with a programming degree) PM me and let's see about getting some data to you/them

or maybe someone can tell me what these curves are:
http://www.facebook.com/photo.php?fbid= ... =1&theater

--BUMP--

The formula has been posted to the wiki! *woohoo*

Would anyone that's good at making things pretty on the wiki have a look at it and maybe give it a makeover? (there are more details on the talk page)

so yogi, get in touch with me if you want that excel workbook - other than that, i think we can consider this topic closed!

Just asking, what is the BasePotionStrength and how do you find it?

lol added further details on the talk page, hoping someone can make it more presentable (feel free!)

Base Potion Strength (BPS) is based off of Alchemy (A), Intelligence (I), Luck (L), Spell Effect Base Cost (BC), and Mortar & Pestle Quality (MQ), from the following:

BPS = MQ * (A + I/10 + L/10) / BC

hopefully it'll be nice and pretty soon