A better way to sort these stamps?

[Bubba Bland]

Back light is when you hold the stamp in front of a good light source. I use a halogen light on my desk and it is strong and very clear light, so I hold the stamp in front of this light and it will show through the paper. Make sure you have the back of the stamp facing you. The design on many of the stamps are so strong that they scatter the image.

I scan most of my single stamps at 300 dpi. This should do it for the water mark trick. Sometime higher magnification creates more problems than the lower resolutions.

Best way is watermark fluid, but as you say, you don't want to use too much of this. When I am doing watermark detection work on something like the 1874-83 issues I use a black watermark tray and fill it high enough that I can do 20 to 30 stamps. I also make sure I shake off as much of the fluid back into the tray as possible before setting the stamps out to dry. Sometimes I have to do a hundred or more. Yes, those issues are difficult to see watermarks on. So are the 1872 for the LC+F watermarks.

Hope this helps.

[Civia Tuteur]

Bubba,
What is a back light and what should I scan the watermarks wtih?
Civia

[Bubba Bland]

I don't know if this trick will work for you on these stamps, but often this works pretty well for me to at least know that there is a watermark to look for.
Trick one. Just use a good back light and see if you can see any watermark showing through This was the watermark will be light and the rest of the paper more opaque.
Trick two. Take a bunch of these and place them upside down on a black stock sheet and scan them. Sometimes you can see the watermark (dark lines this way) but others may not show so well until you view the scan.

By the way, scanned stamps can show the washed out cancels on stamp thought to be mint, or have other problems you may miss when viewing them in hand.

Hope this helps.

[Fernando P-M]

I think you are on the right way, unless you could have access to a Signoscope which is the best instrument to detect watermarks without the use of any fluids but unfortunately it is expensive.

Good luck,

Fernando Perez-Maldonado

[Civia Tuteur]

I am sorting out my many copies (all canceled) of the airmail stamps in the archaeology and architecture series, and I have started with the 12 issues that Scott has listed of the 80 centavo airmail. Because I am trying not to use a lot of watermarking fluid, I am first measuring the perfs, then the size of the vignette, and I watermark at the end.  Is there a better way to sort these stamps?
Civia Tuteur