Got it Peter,

I noticed that ParticleDrag did not respect the ParticleSettings parameter 
either. Thanks for filing the bug!

Another question - does anyone actually like this behavior? Personally, I would 
prefer that ParticleSettings did NOT require that you go back through your 
script and tweak all of your forces.

-n

> On Aug 5, 2015, at 3:26 AM, Peter Crossley <[email protected]> wrote:
> 
> Hi Ned,
> 
> I spotted and logged a bug a couple of months ago about a similar thing for 
> ParticleDrag:
> 
> Bug 47753 -Particles: ParticleDrag: reduced timestep not taken into account 
> when applying drag
> 
> Basically,  if you had 10 steps per frame, the same drag factor will be 
> applied 10 times in the full frame, resulting in much slower particles than 
> with 1 step per frame. The workaround for this is to divide the drag factor 
> by the steps per frame, i.e., for 10 sub frames, change drag from 0.97 to 
> 0.097.
> 
> I didn't investigate other force nodes at that time, but it wouldn't surprise 
> me if others suffered the same problem. I'll add a note to the bug to 
> investigate these too.
> 
> As a workaround for now, Ari's colleague's suggestion is probably a good one 
> to avoid getting bogged down in trying to reverse-engineer what the nodes are 
> actually doing. It also couldn't harm to get in touch with support to 
> escalate the priority.
> 
> Thanks,
> 
> Peter.
> 
> On 05/08/2015 01:33, Ari Rubenstein wrote:
>> Ned
>> 
>> Here is a response from one of our compers at Blue Sky that worked w/ 
>> particle settings heavily over the past year:
>> 
>> "Yes, there is a correlation between particle settings and forces - the 
>> greater the “in-betweens” the higher I needed to set my forces. However, I 
>> didn’t notice a constant numeric ratio between particle settings and 
>> different forces.  As I recall, I had to adjust for each force.  I always 
>> set the particle settings first, then proceeded from there. That’s also why 
>> I used the same particle settings setup for every shot - to keep the 
>> tweaking factor down."
>> 
>> Hope that helps
>> Ari
>> 
>> 
>> 
>> Sent from my iPhone
>> 
>>> On Aug 4, 2015, at 7:13 PM, Ned Wilson <[email protected]> wrote:
>>> 
>>> Hi Ari,
>>> 
>>> The exact opposite. Wind X set to 5 becomes 1 with particle settings at 5.
>>> 
>>> -n
>>> 
>>>> On Aug 4, 2015, at 3:54 PM, Ari Rubenstein <[email protected]> wrote:
>>>> 
>>>> Ned,
>>>> 
>>>> are you saying that a wind X set to 5 becomes 25 with particle settings at 
>>>> 5 ?
>>>> 
>>>> Ari
>>>> 
>>>> 
>>>>> On Aug 4, 2015, at 5:55 PM, Ned Wilson <[email protected]> wrote:
>>>>> 
>>>>> Hello all,
>>>>> 
>>>>> If I drop a ParticleSettings node in my tree, and adjust steps per frame 
>>>>> to be something greater than 1, then it seems to multiply all forces 
>>>>> acting on the particle system by 1/steps per frame.
>>>>> 
>>>>> Is this the desired behavior of the node? If so, do any of you have a 
>>>>> workaround other than to expression link various particle force nodes to 
>>>>> the ParticleSettings node?
>>>>> 
>>>>> Thanks!
>>>>> 
>>>>> -n
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