Here are some sample pictures of what my
QuickBASIC NES emulator produces for this test ROM:

The horizontal lines in the bottom left of the screen (border region) disappear if I scroll it upwards (00 EF or lower).
The QuickBASIC code has a newer version of the filter that runs much
much faster than the C++ version does (if the language difference is ignored), because it updates a running variable only once per channel per pixel, instead of doing 12 or 24 multiplications per pixel. But it is also less accurate, because it rounds to integers. It is unique compared to (probably) every other NES emulator in the world in that it simulates a full frame of television signal, with borders, syncs, colorbursts and all, with the NTSC decoder knowing absolutely nothing about what is happening inside the PPU (things like current scanline number, etc). The only interface between the NTSC decoder and the rest of the emulator is the 1 integer that represents the current voltage level of the NTSC signal that changes about 5 million times in a second.
The older and more accurate C++ version (the one that is documented in the Wiki) flickers between these two (click to zoom):

The third picture is produced if the code merges all three fields.
Note that any possible hardware screen captures depend entirely on what ever postprocessing your television set / composite decoder happens to do with the signal.
If I change my (C++) emulator to merge two fields into one (which a television is certainly not required to do), here is one of the outcomes:

It is quite a close match to the first sample posted by rainwarrior, if we ignore saturation differences.