Equipment Needed For Decoding Tagged Vs. Untagged

I have read somewhere that you need a UV source to differentiate tagged and untaggged US?

Is this true and if so, is there a good website to find such a thing?

Thanks.

Yes, you do. Someone on this forum will be able to tell us whether the US stamps need a long wave UV light, or a short wave one.

I have read that US stamps require shortwave UV. Not sure if any foreign uses long wave uv tagging. Many uv lights can selectively produce short or long wave. Having both makes it nice to use with mineral specimens also.
http://uvminerals.org/fms/uvlights is an explanation of UV lighting

I personally use this one for UV needs.
http://www.mineralab.com/Versalume.htm

Jim

Most Canadian stamps use long wave uv tagging : Long wave: Canada, Mexico, Norway, France, Hong Kong, People#146;s Republic of China, Russia and definitives of Great Britain after 1992.

Short wave: Great Britain, USA, Israel, Finland and older issues from Canada and Mexico.

Use short-wavelength UV to detect tagging on US stamps. My short-wavelength UV lamp is filtered at ~254 nm.

For detecting tagging on other non-US stamps that need long -wavelength excitation, the requirements vary considerably. My long-wavelength lamp is filtered at ~365 nm and will catch most, but not all, and some barely.

I can tell you right now that if you plan on collecting the early GB phosphor issues, I've not been able to find a philatelic grade lamp in the US that works well on those. My UV lamp is research grade, and it won't catch the early GB phosphor issues either. On those GB issues, I've often resorted to collecting a stamp with selvage, because the phosphor bands show well on the blank selvage.

If anyone knows of a UV lamp in the US that will readily detect the early GB phosphors, please let me know!

I use a Raytech LS-7, it works well for me. The phosphor on British stamps can be affected somewhat by soaking - are used stamps giving you the problems? I use my UV lamp in a completely darkened room without windows (I don't have guests, why else would I need a guest bathroom?). To look at phosphor tagging, I hold the lamp almost directly over the stamp with my eyes closed, and then I turn off the lamp and open my eyes. The taggant on used stamps can be fairly easy to see that way. On mint stamps, it jumps out brightly.

Fluorescent tagging doesn't need that sort of run-around, although there are some types (like the unstable OP-4 taggant used for a short while in Canada) that can fade away, making it more difficult to see.

http://www.raytechultraviolet.com/p...t-model7.php

Ryan

Thank you for your reply, Ryan. I am using something very similar to the RayTech, except slightly bigger and slightly higher wattage.


No, these are mint stamps, the earliest experimental phosphors. I have no problem with subsequent issues. In fact, on most subsequent issues, I can see the phosphor bands with the naked eye.

The main problem for me is specifically on 2 sets of early phosphors of 1964 -- the Shakespeare issue and the Forth Road Bridge issue. Some of the stamps in those 2 sets have vertical color bands as a background. Many times, the color bands coincide with the phosphor bands. So unless I have a selvage attached or the phosphor bands are shifted from the color bands, I cannot see the phosphor bands with the naked eye, nor can I see the luminescence clearly with my UV lamp. Power is not a problem, as I am using a medium power research grade filtered UV lamp (it's a little bigger than a house brick). I think my problem may be caused in part by the UV filter, which may be filtering out too much of the UV tail.

I have absolutely no problems with detecting the luminescence from other GB or non-US stamps. I can see the UV excitation without having to turn off any lights.

All the brick-and-mortar stores I went to in the past, the owners also told me they have the same problem with those issues. They've also tried using all the philatelic UV lamps normally available in the US.

The RayTech is nice, but I'm not about the spend $200+ just to detect the phosphor on 2 sets with only a slight premium. It would be cheaper for me to hunt down mint/used sets with selvage.

Thanks again for your reply!

khj --

I hear you on the Shakespeare and Forth Road Bridge. Luckily I have my (used) phosphor sets of those safely in my album and I don't deal in them so I can safely ignore the issue.

For my US, after researching (very, very briefly) about the costs of lamps etc., I made the easy decision that like you, for the sake of a few issues with no significant financial impact, I am not going to make a lamp purchase.

My answer is just to collect one example of the affected issues and not worry what tagging type they may be.

Obviously for dealers and different types of collections it'll be different ...

Actually, I traded about 5 years worth of 5 scientific journals for my lamp.

I wasn't going to be reading those journals anymore, but I knew the lamp could come in handy for...

It's pretty cool to see a whole pane of 50 stamps light up! It's also a pretty safe bet that I wouldn't have forked over $200 for the lamp. But since I do have it, it's provided me 2 decades of enjoyment pursuing tagging varieties/errors/freaks.

k

hello,
Can anyone suggest reasonable cost of uv for USA and all other countries stamps? Are there any that can have interchangeable light bulbs between SW (ShortWave) and LW (LongWave)? TIA

The least expensive option is a battery operated switchable or dual unit. Subway offers one at $71.95 with no brand name mentioned. I have personally used the battery operated Versalume by Raytech (which has recently died and it is not the lamp) and the Raytech ministar LS4. Both use a single lamp with dual output. I have been told by others that the cheap UV lamps are best used in total darkness.

Bill Lehr

I have a Marangue 1008-4182 sold by Staples that is used for currency verification. Works good for me - I have no idea if it short or long wave. Not indicated on machine. Cost less than $100

Unfortunately there is no "catch all" UV lamp for use with all the countries, because they don't all use the same chemical for tagging. For almost all US tagging, you need a short-wave UV lamp (~254nm range). Unless it is filtered, if it has any long-wavelength UV component, your tagging glow may be masked by the paper glow. If you are going to try using one of those currency verification lamps, you need to check the specs.

I am not aware of a model that accepts interchangeable lamps, but I haven't kept up with the UV products in the past 10+ years.

k

I use the UVP Model UVSL-14P, P/N 0188-02 that had both long and short wave. Which ever you need you slidea cover over th other. The
bul is clear on one half and white on the other half. Works off AA batteries. Been uing mine for over 10 years. Easy to find over internet.

I use exact same model and it works great!

What countries do you use it on, eaglebub7 and acanalizo?

I am back to the quandary of do I invest in a lamp, now that I discovered some GB Machins waiting to be sorted that according to SG ONLY exist with some combination of phosphor bands, not without phosphor or with overall phosphor. So there must be at least one band on each of these stamps. But I cannot make out a single band on any of them with the naked eye. It's the first issue of the 2nd class bright blue, by the way, c.1989-1993. I have a stack of them that simply show no bands.

So, can anyone recommend a lamp that does work for GB decimal (Machin / definitive) issues, 1971 - present?