[Dev-luatex] vpack_filter shipout mode?

[linuxss]

Hi, Hans,
I've got almost the same output, as I used 'pre_output_filter' callback 
and a function on a \output command.

1)
\newtoks\oldoutput
\oldoutput=\expandafter{\the\output}
\output{
    \directlua{node_check(tex.box[255], 'shipout')}
    \the\oldoutput
}

2) callback.add('pre_output_filter', node_check, 'info')

and I can't see here table and page number nodes.
pre_output_filter sounds like the all output should be prepared :)
if I use 'vpack_filter' i see all the nodes of the page.

so that means, that 'vpack_filter' is closer to shipout then 
pre_output_filter?
I thought is has to be in reverse :)

question: when the pages and table are inserted into \box 255?

Thanks, Linas