offsetting starting frame of camera?

[chazfest]

Hi Houdini heads,

I'm currently working on a fluid simulation scene (purely experimental, recreational and part of my ever lasting learning curve), involving a matchmoved camera from a live action plate.

The emitter is inside a train tunnel on a london underground platform, the plan is to flood the train track.

It's apparent that the sim will need a little head start on the scene to get flowing, so I'm wondering if I could set the camera to start at a later frame? Delaying it by, maybe, 30-40 frames or so?

I've attached a very early pre viz of the sim, just to show the scene setup:

http://www.mediafire.com/?coecds3ao4zjx30

Obviously it's in the (very) early stages and doesn't include the live action plate.

Any advice on how to accomplish this would be massively appreciated.

Thanks in advance.

Chaz

[chazfest]

Also, if anyone could advise how I can avoid the oversized blobs and globbules of fluid, specifically evident on the platform, that would also be a huge bonus.

Thanks (again) in advance.

Chaz

[Erik_JE]

What fluid method are you using? FLIP? If FLIP you need to decrease your particle separation to get more detail.

Regarding offsetting the camera its probably easier to offset the actual simulation instead. Run it from start and an extra 40 frames and write it out. Then make it load frame 40 for frame 1 or something.

[chazfest]

What fluid method are you using? FLIP? If FLIP you need to decrease your particle separation to get more detail.

Regarding offsetting the camera its probably easier to offset the actual simulation instead. Run it from start and an extra 40 frames and write it out. Then make it load frame 40 for frame 1 or something.

Awesome, thanks for the feedback Erik!

I am indeed using FLIP, I'll increase the particle separation as advised and run some tests.

Also, I'll need to refer back to an Digi Tutes lesson to write out the sim files. Can't quite remember how to write them out then bring them back in again. Shameful, I know. I'm pretty new to this though, and as I my day job is as a video editor, I'm learning in my spare time, with the help of kind individuals like yourself

Great community btw, I really rate the Houdini community highly, very friendly indeed.

Thanks again for the advice anyway, I'm off to run some more tests

[Erik_JE]

Awesome, thanks for the feedback Erik!

I am indeed using FLIP, I'll increase the particle separation as advised and run some tests.

Also, I'll need to refer back to an Digi Tutes lesson to write out the sim files. Can't quite remember how to write them out then bring them back in again. Shameful, I know. I'm pretty new to this though, and as I my day job is as a video editor, I'm learning in my spare time, with the help of kind individuals like yourself

Great community btw, I really rate the Houdini community highly, very friendly indeed.

Thanks again for the advice anyway, I'm off to run some more tests

Yeah the Houdini community is awsome.

Make sure you decrease the particle seperation and not increase it. It is at 0.1 by default and you want to get down around 0.04 to get more particles and finer detail.

I prefer writing out sims using the ROP Output node and then loading the sim files in using a regular File node.

Some people like to write out the surface directly but i prefer to write out the actual sim and then write out the surface in a separate step as it leaves more options too tweak the surfacing to get it right without having to re-sim.