Perforation Gauging Manual Vs Electronic?

javascript:insertsmilie('')I noticed a few members referred to electronic perforation. I wonder how precise the new tools are, and how does it compare to the last 150+years of manually checking perforations. attached are a couple of my gauges, scanned at 600 dpi. Can someone electronicly perf to verify that a perf 12.3 (or any other number)instata is same whe3n electronically perferd? I saw this tread on Canada small queen, but focus was on potentially shrinking stamps...which may be possible with paper, but unlikely with plastic gauges.
Your help will be appreciated

I will scan my gauges and rulers and measure them in AutoCad and post the results here.

That would be great BC

PART 1.

I do not have the gauges that Gilles has, but I do have a Unitrade gauge similar to the Gibbons Instanta.

First I measured the Unitrade scale with a steel engineering ruler that I have, and there is an exact match. I then scanned the Unitrade scale at 600dpi and inserted it as a raster image into AutoCad. I then drew a scale in AutoCad similar to the one on the Unitrade gauge. I drew it independently, I did NOT trace the Unitrade scale.

I ligned the AutoCad scale (in red and yellow) up to the Unitrade and and there is close to an exact match! This shows that AutoCad, my scanner, and the Unitrade scales are calibrated, so any stamp that I scan and insert into AutoCAD will get true measurenments.

The advantage with the AutoCad scale is that the measuring lines are finer.





Stay tuned for Part2...

That is great BC

Hi BeeSee

I know you use AutoCad for measuring, and it is very, very accurate, but when you round off....

Example 12.2 can be 12.25 or 12.00

That has been bugging me...So here is my answer to all the gauge measuring discrepancies we encounter...(remember, I AM NO EXPERT)

I use GIMP which can measure distances that are accurate, even if you zoom in or out which would take care of all individual programs (viewers) that show stamps at different degrees of zoom.

See below






Now bare with me...If you take a pixel reading of a KNOWN perforation on a stamp and keep a record of it...Then NO mater what old stamp you measure, (example. if 12.25 perf = 200 pixels) then if the stamp reads 200 pixels...It has to be exactly 12.25....We would never need gauges again.

Gimp also measures in these modes as well as pixels
pixels
inches
millimetres
points
picas
centimetres
metres
feet
yards
typogr.points
typogr.picas

Wert, Gimp seems like Paintshop pro, another raster program. I get the same results as you in Gimp from Paintshop Pro. They are excellent.

While AutoCad is vector based (and allowing raster imports), it has the same (or better) rounding capabilities. I prefer AutoCad because it is my profession and I can use it way faster then any other program. It also has zooming without worrying about pixels.

Right now I am drawing a perforation gauge just like the Unitrade one (from scratch) and I will post the results when done.

BeeSee...I am aware that AutoCad is the best product, I think what I was referring to was what was in the quote above...Gauges are left to individuals to interpret the what they are trying to analysis....When I saw you working with AutoCad, I thought..Hey..That guy is on to something with those accurate measurements he is producing.

I was just trying to use that technology to a simple but higher level of stamp analysis....But, then I could be talking through my and your hat...

Wert - we are both proving the same thing in slightly different ways; electronic perforation measuring is just as good, or better, than the old way.

Part 2

Here is my AutoCad drawn gauge, inserted over the Unitrade gauge. Again, we have almost a perfect match.



Again,I did NOT trace the Unitrade gauge, I drew it to scale independently.

We can now say the the Unitrade gauge and AutoCad are equally accurate for measuring perforations.

Part 3 to come... bringing in a small queen stamp for measurement.

Gilles, if you can send me a 600dpi scan of your Instanta, I can import it to AutoCad and check it out. The one above is to small to synchronize accurately. Email me at: bc (at) brcstamps.com

Part 3

Here I insert a stamp that I suspect is a 1st Ottawa printing. It is from a cover previously shown here:

https://goscf.com/t/22248&whichpage=4#198586

The date Mar 8 Mar 3, 1872 is only seven two days after the first Montreal printings are known (March 1) and the colour is rose (though it looks more rose in real life than in the scan).

Final proof would be the perforation, as first Ottawa printings are always between 11.8 and 11.9 (except the rare 11.5 perf).

The stamp was scanned the same time as the Unitrade gauge so it is synchronized.

Here is what I get: a reading close to 11.85 - proof of a 1st Ottawa printing! I get a similar reading by using the actual Unitrade gauge on the cover, but it is quite difficult to read without a magnifying glass.



I drew the blue perforations in AutoCad to make them easier to see.

I am very pleased with all the interest this has sparked. I have put off my classifications of small queens from months due to all the difficulties in perf but I can finally see light in the tunnel and can't wait to get at it. Thanks a lot BC and all others who have contributed to answer my initial simple question

The e gauge I use is derived from the "new" instanta and was calibrated by the designer . I've also perffed many known stamps to know that provided the scan is 600dpi I can accuratlly get results. I also have the clear unitrade gauge Bee is using for reference on his experiment or better put his creation. I can accuratly hold a stamp to the clear gauge and using magnification get a pretty good result but when were talking .1-.2 of a perf being able to zoom in is so much of an advantage . With the E gauge I use I can take a 600dpi scan and blow it up X200-300 and the gauge expands within the image as well so its extremely usefull. Below is the gauge and a couple examples in use. NOTE the image of the gauge is from photobucket and not accurately displayed for use. For reference I have used a 15c large queen that I find to be perf 12.2 - for comparison I have done the perffing at 12-12.2 and 12.5 to show the differences. NO WAY COULD I DO THAT BY HAND AND BY EYE.

Nitro, can you email me your gauge? I know I had it at one time but cannot find it. I want to import it into AutoCad for caparison.

Mariost, I shall be looking forward to testing your gauge.