message: Make sure that base file exists, before checking for UDIM pattern
diff: @@ -329,6 +329,11 @@ bool Texture2D::checkForUDIM(FileName filename)
  if (hasUDIM())
  return true;
  + // Make sure base file even exists
  + std::ifstream f(fullName.c_str());
  + if (!f.good())
  + return false;
  +
  // See if base tile "1001" is in the filename. If not, it's not a UDIM.
  auto found = fullName.rfind("1001");
  if (found == std::string::npos)
  