I have 2x crompton 70w "mercury vapour" lamps and I want to verify their wattages because I have never heard of a 70w "merc". Both etches are worn to a point where they are unreadable. One has the physical coating of the etch gone and only has a light yellow etch stains while the other has no yellow remains but has some of the etch left. If I angle it just right, I can barely read it. Is there any way to read it?

Are you sure they're MV lamps and not mercury halide or other metal halide lamps? 70w makes me think of a SON mercury vapor replacement with built in ignitor.

As for your question - several methods are used by radio collectors.

- Cool down the tube a bit and then breathe on it to make the moisture condensate. Sometimes the condensation will appear on the glass but not on the print. Do NOT wipe the condensation off - that'll be the last of your print.
- Make a HDR photo of the print. Use Gimp or Photoshop to adjust the curves to get any faint detail out of the picture. That way you can usually see more than by eye.
- Use UV light. Sometimes you get lucky and the print is slightly fluorescent.

I have tries all methods, including saturating and contrasting. I also created a representation of the etch based on what I found. I am not sure about the F in MBF but that is the closest letter. The pictures are of the original, saturated and edited.

Update- Oops ! I read the etch wrong and it is a MBI-S/E. Sorry for the confusion!

This thread has some ideas for renewing etches.
https://www.lighting-gallery.net/gallery/displayimage.php?album=topn&cat=-7404&pos=5&pid=196960