Best Watermark Detection?

With the Signoscope, there is also a reflection from the thin mylar film which intensifies the differences in thickness in the stamp being examined. This works very well except when there are hinge or paper remnants on the stamp.

It works by lighting the stamp from the side. As bookbndrbob says, a piece of mylar is placed on the stamp and clamped down because everything needs to be flat, and it reflects light, as does a piece of plexiglas (or somesuch) on top of everything. A stamp alone clamped down doesn't work.

By the way, if you have one, I wore out or lost the little mylar foils that are supplied long ago. I substituted cut pieces of Glad wrap and those work fine.

JKJBlue- do you feel that Clarity works better than Ronsonol? I tried Clarity 15 or 20 years ago and for the cost it didn't seem any better to me than Ronsonal (other than being non-flammable).

I actually had good success with the Signoscope just placing the stamps in between the pieces of glass without the little mylar film. The only times I ever used the mylar film was when I could not see the watermark with just the stamp between the glass pieces. The film did help me see some very difficult (though not all) watermarks, especially modern ones in very thick paper stamps 1970s-on).

For more classic stamps, one should be able to see almost all of them with fluid. I like the idea of a dark or black glass tray for watermarking. Was never aware of any issues with plastic but did notice at times there would be these very tiny black "floaters" in the fluid. Never had any idea what they were and never saw one once the fluid evaporated off the stamp. Are they a problem?

I use Clarity because it is the safest, and it works well for my purposes - checking the many possible watermarks in a WW collection.

In my undergraduate days, I had a good deal of exposure to flammable and noxious chemicals and solvents. (Chemistry Degree)

Been there - done that. No more.

The Signoscope must have evolved since I got mine. Mine has just one little brick of plexiglas/perspex which swings out over an aluminum tray. Mine was bought secondhand about 1990.

Signoscope is a major disappointment, mine (3 years old) seems to work best on the watermarks you can visually see and is worthless on difficult stamps.

No full-time dealer that I know uses a Signoscope. We're folks who sell stamps for a living, and being able to properly identify watermarks and faults determines whether we will be successful or not.

That should tell you all you need to know...

...and the corollary: 99% of the full-time dealers I know use Ronsonol (I do too). That's no coincidence either.

I don't know why some people seem to have so much trouble and disappointment with the Signoscope... Mine works fine. I have a feeling people aren't using them properly or something. It's a simple enough process. The only time I have a problem is if there is a paper or hinge remnant left behind on it.

As for those who sell stamps for a living. I agree, most I know don't use a signoscope but it's not because of performance, it's due to cost and the fact they many are scraping to get by as it is (or at least that's the story). When I've asked about this the answer has been I can by a lot of lighter fluid for the same price.

Jeff

Yes it is. Signoscope is virtually worthless for stamps with hinge remnants (or any adherence for that matter), can't detect difficult watermarks (even with recommended spacers,) and can't be used on most multiples (too large to fit). It does an inferior job vs. Ronsonol at detecting faults & alterations (in fact, basically can't detect anything that would only "flash" in fluid).

Collectors who use Signoscopes might do so to avoid toxicology concerns with fluid, but Clarity (no toxicology concerns) would be an order of magnitude superior.

I've probably handled a dozen Signoscopes (acquired from buying out estates) and have zero interest in keeping one, even for free.

I find most dealers (not all!) are very, shall we say, cost-aware. I suspect that is a strong motivation to use Ronsonol vs. Clarity.

Also, if you're a dealer and don't carry stamp supplies, Ronsonol is easy to obtain.



When I've been stuck somewhere without good ventilation and was testing a bunch of stamps for a couple of hours, Ronsonol has bothered my eyes and lungs. It's drying and a fat/grease solvent, and there are small amounts of impurities besides. I should maybe drop old contacts into it to see what happens.

Convenience: there has to be a convenient place on the work desk for a Signoscope, otherwise you won't want to drag it out every time you want to use it. If you've got a lot to process (like a dealer), Ronsonol or Clarity will get things done much faster.

As for seeing through hinges and adherences, I can still remove most of them quite well and fast enough to justify the time spent when it came time to sell.

Difficult watermarks are just that, difficult watermarks. I find the Signoscope actually better for some things like the British Commonwealth spiral watermarks on the somewhat thick paper used during its time frame.

I don't have a Signoscope, so I can't speak to that. However, as for Ronsonol vs Clarity, I've used both a fair amount. For me, they both seem to perform pretty well but Ronsonol seems to give me a slight (maybe 0.5-1 sec) longer "flash" for seeing the watermarks. I can't prove that scientifically, it's just my personal experience: for non-obvious marks, I found myself having to re-dip in Clarity multiple times to be certain vs only once or twice for Ronsonol.

I always use it in small quantities (a couple stamps at most) in an open, ventilated room so the toxic fumes concern is negligible for me.

Where do you buy Clarity.....it might be in the 7 pages of posting but my read of the last pages just mentioned it and APS Wedsite does not talk about it !
Thanks-Rene