Is there a trick to photographing overstruck coins to make the original more visible?

[coinnoob7]

I have a few I see things in under microscope but can't get what I'm seeing to show up in photos, which would be hugely helpful for making overlays in photoshop to find a match. It makes me want to find someone with access to a scanning electron microscope and beg for their scan.

Are there any known examples of peace or morgans struck over other coins?

[UNCLE BINGO]

Are you talking about Daniel Carr kind of stuff , mint error struck on different Planchet , or just clashes ???? Maybe try using a different light source than what is on your scope . like a flashlight from the side if that makes any sense. Sorry i am confused by your question .. Are you seeing stuff like this http://ec2-13-58-222-16.us-east-2.compu ... ashed_dies

[messydesk]

I have a few I see things in under microscope but can't get what I'm seeing to show up in photos, which would be hugely helpful for making overlays in photoshop to find a match. It makes me want to find someone with access to a scanning electron microscope and beg for their scan.

Are there any known examples of peace or morgans struck over other coins?

No. All struck on fresh planchets.

US coins struck over other coins being legitimately used as planchets are limited to early copper as far as I know, with Conder tokens usually being the host - Druid halfpennies and Talbot, Allum, & Lee cents coming to mind.

[UNCLE BINGO]

If you have a few years to kill this website is fascinating https://minterrornews.com/glossarymultipleerrors.html

[alefzero]

I have a few I see things in under microscope but can't get what I'm seeing to show up in photos, which would be hugely helpful for making overlays in photoshop to find a match. It makes me want to find someone with access to a scanning electron microscope and beg for their scan.

Are there any known examples of peace or morgans struck over other coins?

No. All struck on fresh planchets.

US coins struck over other coins being legitimately used as planchets are limited to early copper as far as I know, with Conder tokens usually being the host - Druid halfpennies and Talbot, Allum, & Lee cents coming to mind.

Also there is a 1795 B-4/BB-14 Flowing Hair dollar ("hidden star" variety) struck on a 1794 B-1/BB-1 Flowing Hair dollar. I also have a 1795 B-1/BB-21 Flowing Hair dollar that possibly was struck on a 1794 B-1/BB-1 Flowing Hair dollar, but I am nearly certain it was simply double-struck. The reason it is inconclusive is that the 1794 dollars had strong central devices and nearly no detail along the periphery, the stars and legend. So the doubling is confined to the centers, as on my coin. The two images are in roughly the same orientation on my coin, which could have been deliberate of an overstrike, while the known overstrike was rotated and flipped. The obverse is overstruck on the 1794 reverse.

Here is an article announcing the confirmed fined.

https://minterrornews.com/discoveries-7 ... 94_$1.html

[RogerB]

You need to use a 3D optical profilometer, not a regular camera.

Nice ones start at about $50,000 and go up from there.

Keyence 3D profilometer

Image1.jpg (98.31 KiB) Viewed 1146 times

[weth]

There are different scanning techniques that can work, as Roger pointed out; not a lot can be done with simple optics.

I've thought about scanning some of the Brazil 960 reis overstrikes for which I can't quite make out what's underneath...

[coinnoob7]

You need to use a 3D optical profilometer, not a regular camera.

Nice ones start at about $50,000 and go up from there.

Keyence 3D profilometer

Image1.jpg

I was just coming to the forum to ask about this - how to accurately measure relief, not regarding overstrikes but there are a few coins that look unusually high/low and I'd much prefer to gather data on many coins and show the relief of one is statistically significant rather than just eyeballing it. The 3d scanning techniques I've seen don't work well with reflective materials (and are very expensive). A touch probe scanner would work but I'd want to try it with some junk coins first to make sure the probe doesn't leave marks.

I suppose the reasonable thing to do is just take photos at a very steep angle of something like the neck line where there is a large surface at an angle, but with how much die polishing can very it would be better to find the height between to parts of the design.

What would be the safest (for the coin) way to make a mold, wax? Silicone?

Do the grading companies have a quantitative way of doing this (such as a profilometer)? Do any numismatic museums?

[RogerB]

You can also use a visual microscope with calibrated micrometer focus capability. With correct use, and some practice this can give you very good estimates of relief differences between points on a coin. The operation is simple: At high magnification accurate focus is critical. The difference between correct focus for one point on a flat item, and another point on the same item can be measured by how much a micrometer wheel/gear has to be turned to adjust focus from the first point to a second. (The same basic process is used with a micrometer stage that can measure length and width of a magnified object.) You might be able to find a used HS or college-vintage one for $500. A Keyence optical starts at about $50,000.

Here's a 3D microprofilometer image the I posted on NGC's message board.

"This might be a clearer image of mushy details on a coin. This is the letter "I" in LIBERTY on a modern quarter. Any metal not parallel to the coin's field (table) contributes to reduced contrast and softer-looking details. Notice the irregular top surface of the letter, and the slight rise in the field adjacent to the letter."

1201465220_LetterI-detail.jpg.cfe201c2fe41503870e2a1e75fe6145e.jpg (182.06 KiB) Viewed 1072 times

The thread URL is: https://boards.ngccoin.com/topic/427976 ... nt-9807018.

The mesh grid helps support colors and tones used to indicate relief. This kind of device will produce accurate measurements of coin relief. Visual and photographic methods are capable of useful approximations. (But only when used by someone who understands what they are doping and limitations of those methodologies.)

[UNCLE BINGO]

I was extremely interested in this technology a while back . https://www.zeiss.com/metrology/product ... ISEALw_wcB and Roger has said a very wise thing about maybe picking something like it up refurbished,,, after the new wears off the price tag ... You don't wanna be like the guy that bought the very first laser disc player ... I don't know if something like it would really do what you are asking or not . I just did not want to have to z Stack pictures .

[RogerB]

The ZEISS Visioner 1 uses image stacking as mentioned earlier, except they automate the process. It can produce nice images, but will give you no information about design relief.

[vampicker]

Just a suggestion here for any newer collector - before dropping thousands or more on fancy equipment because you think you see 'something' , send the piece to someone who actually knows what they're doing. A couple of us are professional attributers and one of us is a fairly skilled photographer as well.
But I'll tell you up front, it's highly likely what you think you see is a trick of the eye. I think on some level the tricky looking stuff has gotten all of us at the beginning

[morganman]

Vamming should be simple withot thinking to much or
trying to micro vam everything. Pictures IMHO are much
tougher, learning various approaches & equipt is very
tough/hard IMHO. As a tech dinosaur learning pics is a no
for me, as frustration runs rampant. I find others struggling
as well.Spending much on equipt is not a good idea period

Let others with experience & equipt do pics IMHO

[UNCLE BINGO]

Well I guess I better clarify something , I did not run out and buy that ziess ... Those Germans are very proud of the stuff they make . Anything like that does not come with pricing , is generally the price of a small island However I am going to keep my eye on that tech . And see where it evolves ... Give it 10 years and see where the pricing goes .

[RogerB]

Morganman and Vampicker mention some good points. Now....how about acting on them?

[vampicker]

It's often the right (and kinder in the long run) thing to tell someone they're probably or definitely wrong.

Don't think I need to post my resume for this field

[UNCLE BINGO]

You know I agree with you guys about seeking expert advice , I was very confused by what the OP was asking in the original title of this thread .

[RogerB]

The OP's question might have wanted the answer "axial lighting." That's a way to produce the greatest definition in relief - but only if accurately done.

[coinnoob7]

The OP's question might have wanted the answer "axial lighting." That's a way to produce the greatest definition in relief - but only if accurately done.

Axial lighting is how I first noticed the coins I'm interested in measuring. What do you mean by accurately done? I've been frustrated by just how inconsistent the photos are from the grading companies and auction houses. It makes me wish there was a set of standards in numismatic photography, that is a document that specifies exactly which lightbulbs, how far to place them, the size/material for the tube placed over the coin to block off axis light, camera settings, etc. I can see why the TPGs and auction houses don't have an agreed upon standard, they're trying to make coins look good to make customers happy, but for numismatic research sake it would be nice if they took photos by some standard and also included their beauty shots.

Just a suggestion here for any newer collector - before dropping thousands or more on fancy equipment because you think you see 'something' , send the piece to someone who actually knows what they're doing. A couple of us are professional attributers and one of us is a fairly skilled photographer as well.
But I'll tell you up front, it's highly likely what you think you see is a trick of the eye. I think on some level the tricky looking stuff has gotten all of us at the beginning

I have a lot I'd love to send to you, vampicker, can't afford the shipping with enough insurance to feel safe. Certainly can't afford the expensive equipment mentioned here, or even to rent, but knowing what equipment could be used is a start, maybe I'll find a person/company/university lab/museum that will grant me access.

I do appreciate the expertise from all of you. Thanks for the help. Yes I agree its more likely its a trick of the eye, that's why I want something more quantitative like a 3D scan.

It's often the right (and kinder in the long run) thing to tell someone they're probably or definitely wrong.

Don't think I need to post my resume for this field

very true. Also helpful in that it often motivates people to prove themselves right in some irrefutable way.


What I'll try is finding some focus stacking software or photo editing tool that can remove the parts of an image not in focus, then with my cameras aperture wide open step through the focus adjustment taking photos at each step.

Thanks for your help.

[vampicker]

If you are going to the FUN show in January, I'll be there at the company table offering examinations and opinions, Messydesk is usually there with his photo set up as well.