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Europe/Great Britain : What constitutes a phosphor or perf shift.?

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Silence in the face of adversity is the father of complicity and collusion, the first cousins of conspiracy..
16 Jul 2013
On the Machin Index, a site devoted to these immensely interesting, but sometimes complicated Machin issues, a member asked;
" .... Having recently read the comment about the shifts in iridescent layer(& not having a Deegam catalogue) I was wondering how much of a shift qualifies as a "shift" ? ...."
This is a good question that I thought might be worth posting here to members of SoR. The established criteria needs to be kept in mind when evaluating whether to bid on an example offered on some auction sites where, at times, the lack of knowledge is astounding and only balanced by the amount of misleading hype.

To begin, Royal Mail has added phosphor bars or bands to the Machin stamps so that the mail can be quickly sorted and aligned for the cancelling machine. To separate first class mail from second class these phosphor identifiers may be a single bar or band usually down the center, or two bars or bands, one at either edge of the stamp. The ALF machine can measure the time between bars, or bands, and thus determine the level of service, plus turn the envelopes so that a cancellation can cover the right upper coiner and usually the stamp. Often that actually works. (Intended Sarcasm)
In most printings the bars or bands are placed on the rolling sheet after the image is produced. The perforations are ground in after the printing process as well.
Quite often the workers are not as interested in perfect alignment as the printed images are passed through the appropriate machines since for their purposes, the system will work despite slight misalignments.
However minor variations like that excite the Machinista.
And thus the question was asked.
To meet the Deegam Criteria for a phosphor shift, the phosphor must clear the perforations, but remember, to use this rule of thumb, the image on the stamp in question must be well centered.
This is explained in great detail with images to provide examples in both DR-53-5 and the handbook in Chapter 11, pages 12, 13, and 14.
That is because it can be that, what appears to be a phosphor shift is caused by the perfs, which are added after the image, not being well centered.
In sideways shifts, pay attention to the phosphor being clear of the regular perfs, but not quite of the elliptical perforation and thus as far as the Deegam Handbook is concerned, while interesting, that shift fails to meet the established criteria.
As mentioned this is all explained clearly both in prose and drawings, and then the chapter leads into a discussion of Doug's "SIN" system of identifying the different variations of different shifts.
The "SIN" system was disappointment to me as it refers to whether the bar is;
"Short, Inset or Notched" and not what I originally thought.
"Short" = Up or down or both,
"Inset" = Left or right,
"Notched = When the bar was intended to be notched to allow for a multi-value pane that has stamps with different, sometimes complex bar arrangements is not correctly aligned.
It is also possible that what should be a full sized bar covering the stamp and not the gutter betwixt adjacent stamps is misaligned so far that is appears to be "interrupted" when you examine the stamp.
Finding such an example while sorting common kiloware will set the collectors heart a-thumping.

This is but a brief blurb to answer the query but the Handbook covers this in great detail and without a copy ( Shameless plug: Now available on a disc as so many sources of information are.) of the Complete Deegam Machin Handbook so much is being missed.

Obviously other catalogs may use different criteria, but the Deegam is really the most comprehensive source of information about the ubiquitous Machin issue which started in 1967 and continues to this date and, I expect, will continue as long as the Queen survives. There are now about 500 easily identifiable color/varieties that alone could make a presentable display. With a little bit of effort, a magnifying glass at hand and some knowledge of the differences, that number can be increased to about 1,000 varieties, virtually all commonly available. Only a few call for any significant premium so affordability is hardly a problem to those who seek postally used, nice copies. The mint, never hinged, Machin collector will probably spend as much on mounts and albums as the stamps he purchases.
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The past is a foreign country, they do things different there.
16 Jul 2013
re: What constitutes a phosphor or perf shift.?


Not enough superlatives in my vocabulary to adequately critique your scholarship. Time for you to consolidate
your knowledge of "Machins" into a permanent and definitive Stamporama article on the subject.

The British PO seems to be possessed by the horror that some otherwise upright citizen might, just might, reuse
an inadequately cancelled postage stamp. Those phosphor bars/bands reminds me of the luggage conveyor belts
in major German airports: no matter where the baggage tag on the exterior of your luggage is located, it will be read
and your luggage will be on the same aeroplane as you. In the rare event a stamp is not properly cancelled, the British fail-safe mechanism of making it hyper-difficult to remove all of the stamp from paper intimidates all but the professional philatelist.

Your contribution to phosphor/perforation shifts is perilously close to being "A Brief History of Philatelic Time".
I enjoyed reading it.

John Derry

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Silence in the face of adversity is the father of complicity and collusion, the first cousins of conspiracy..
17 Jul 2013
re: What constitutes a phosphor or perf shift.?

To be brutally Honest, John, the scholarship belongs to Douglas Myall, "Deegam" himself who had studied this issue from it inception in great detail and tabulated the Compendium of Stamp and Machin knowledge known as "The Complete Deegam Machin Handbook" which I use extensively as my main source and without which Machin Stamp collectors would be like disoriented spelunkers whose torch went out..

For those who never saw a copy when it was still on paper the two volumes were up to some 1,500 pages, to which the Deegam Reports must have added another five hundred pages, all about this ongoing issue.
The thing that I found so interesting is that Volume One was some 700 page of some twelve chapters and appendices that explained a vast amount of information about how stamps in general, and Machins in particular, are produced, monitored, colored, perforated, over printed with phosphor lines and coated at times with fluorescent dye that shows up under long or short wave light.
The second volume listed every single imaginable variation in three main levels so that newcomers can start simply at level one and as they learn about the myriad of varieties they can advance their collections to the second and third levels.

The books in text form became so unwieldy that they were carefully converted to disc format and by now would easily constitute over 2,000 pages were they still in loose leaf binder format.

So the praise, John, goes to Doug who will be 91 in this December and has spent forty five years gathering and sharing all this information.

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