UpResing and Substeps

I may be wrong here but just did a very long sim test and the base render was fine, I used 3 SS in both frame and pressure. Now when i simmed the upres I set the SS back to 1…it would have been a crippling sim otherwise. I got stepping in that render. It may well be the case that you have to leave SS as if when upresing. I may be wrong…correct me if so. But do some tests before you commit.
Personally I am not a great fan of upresing preferring to do a low res sim to check general shape is OK then upping the res. OK the shape changes but generally for the better and I can get a good % done on a very high res sim on my GPU. Also when upresing the normal sim needs velocity cache which really pushes the file size up and takes longer to sim. As a side note a good proportion of my render time is spent " preparing"…I suspect this is due to a slow hard drive. When i get the dollar I shall have to make a choice between upgrading my GPU first or an SSD.

Could you post samples of the stepping artifacts you are seeing and a minimal reproducer scene?
Thank you.

Sadly I deleted both caches and am going with straight no up res. Here a still from the upres with the stepping which was not apparent in the normal sim…remember I had SS at 2 the back to 1 for the upres which i think may be the cause. I am planning some tutorials (commercial) on these experiments. Rats cannot

u/l tif !!

Cannot u/l a c4d file to a reply i will mail it to you

sent to forum@jawset… I know the setup may be wrong I am experimenting with ideas…fast wind with 50% time scale then i will do slow wind at 100 % but I think that will loose the impact going slower

Here is a render from the file I sent…different frame I have not go as far yet !! But no stepping at a high resolution! Oh…I spun the bullet in this…delete the rotation to test as it may have an influence! Yes the rotation has a big influence

I have enabled several compressed file format extensions for upload. zip, 7z, bz2, gz

ok will zip in future Discourse software ?..err why ask !! I know it is Discourse !!

Here is the high res sim 2 steps ( no upres) smooth as a baby’s bottom. No bullet rotation