images.toseries() 'auto' setting fails if length is larger then 100,000

[boazmohar]

data = thunder.images.fromrandom(shape=(110000,10,10,10), engine=sc))
data.toseries()

leads to weird chunking as:

if chunk_size is 'auto':
    chunk_size = str(int(100000.0/self.shape[0])))

chunk_size
out: '0'