Please Help Identify China Stamps

Bumping this old thread. I have a question for the group but want to put it all into context.

I purchased a C5 set off ebay which included both original and reprints. I can confirm that long wave UV does indeed cause the originals to fluoresce whereas the reprints remain dull. I used other features to confirm such as the original paper being thicker and more yellowish.

S2 is a good example of the UV lamp being a good identification tool. S2 reprints are readily apparent due to the extra horizontal line between the ox farmers legs. Coincidentally, the UV lamp makes the originals fluoresce while reprints remain dull.

My issue is with C8. I want to know if the UV test is TRULY helpful in differentiating originial vs reprints for C8 (and C8NE). I purchased an "original" set which does fluoresce. Then I purchased another "reprint" set which also fluoresces. Either (1) both originals and reprints BOTH fluoresce under UV (Scott and other sources say only originals fluoresce) or (2) the reprint set I bought was misidentified and really is original print.

Other sources say that you can differentiate C8 originals vs reprints based on how thick and dark the background map lines are. I don't have any reference examples so I don't know the thresholds to make the call.

Do you folks have any documentation or scans to help? I'll try to pull together some zoomed in scans and post them here for further scrutiny.

Thanks!

C5, C8 and C9 are notoriously difficult to differentiate between the originals and reprints#65292; since the designs are identical and the only difference is the paper and the color.

I would like your opinion of a blue dot in the left outter frame line of the 30000 1L154 stamp

Blob of stray ink? Or a paper inclusion?

Robert