Numismatic and History Discussion Forums > Coin Photography, Conservation and Storage

Your advice needed for cutting and cropping coins

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Istinpolin:
Dear Friends

I have been facing some problems with my images. I use a Sony DSC-P150 with 7.2MP and very good macro function.

Along with that I am using a tripod to take images. I elevate the coin to bring it closer to the lense and have white paper under the coin.

I am using Photoshop 7.0 to make the coin look as natural as I can.

However, I always have some shade from the angle of light that I would like to get rid off. I couls use the magic wand but one needs a calm hand for that and it takes too much time as I process 100 coins sometimes.

Is there a way fast and good way to cut the coin out of the background completly and put it on a background that I have made myself, so that the coin seems like floating? Any andvice would be appreciated.

Best wishes,
Burak

slokind:
Dear Burak,
The exact set-up can vary according to equipment and space (I have a copy stand, but I used to use a tripod, for example).
But the answer to your problem is a white dish (mine is a white oven-ware glass baking dish) and a  sheet of ground glass or any non-glare treated glass about 30 cm. square.  You buy it at a normal glass shop or at a picture framing shop, and ask them to smooth the cut edges.  The lamp I use is an Ott-Lite folding desk lamp, but any mini-fluorescent, any lamp that is diffuse, is good.
The important thing is the white dish (or shallow box) with the ground glass (so not shiny, not glinting) on it so that THE COIN IS RAISED 4-5cm above the bottom of the white dish.  Sufficient light, passing through the glass, is reflected back from the bottom of the white dish so that you get no shadow at all.
Now that I have a tiny camera for snapshots, I used it to take a picture of my Nikon 5700 mounted in position.  I have found that with 5MP and 8X zoom, the camera mounted about level with the Ott-Lite, when the lens is extended to take a picture, it is about 10 cm above the coin.  I do a pre-focus, pre-exposure off the coin itself (no matter if it is a hemiobol that does not fill the center of the frame).  This gives me enough depth of field that both the center of the coin and its edges are sharp.  I don't like to have to 'sharpen' an image in post-processing, though a little is desirable on a big image of a tiny coin.
Pat L.
P.S. here is an image of a little dark bronze 10mm coin of Klazomenai.  It hasn't been 'cut' or 'cropped' at all.  I do hate using that 'magic wand'!  With this image, not necessary.  Just use paint bucket.  I don't like orange, but for a demo, OK

Istinpolin:
Well first of all Pat, I am impressed by your set up. It is too proffesional for my means. I have made a 15cmx15cmx15cm all black box painted with acryl, but instead of a glass plate I use a big nail with a wide head softenen with dried glue. I was thinking of using a glass plate, but I am generallz lazy when it comes to dusting ad cleaning. The problem I have with this sized box is that I cannot put the tripod around without going far from the coin, which means I am taking the image from too far away. Thats why I have switched to a primitive solution of white A4 paper, elevating the coin by 7cm from that paper and have the lense 4cm above the coin. Below you can see the an example of a Maximinus I that I photographed this way.

I defininitly will switch to your system but I would like to ask you some few questions if I may. You mention the deep dish you. I can probably use anything in this shape, but what about the material. Would wood do it? Does it have to be non shiny porcelan?  I have a custom made box like I said before, but I do not know if you have seen that specific Simpsons episode, it looks like the Spice Rack Homer built for Marge. In other words it is horrible.

You also mentioned the size of about 30cm. Is that the diagonal shape? Can I use a smaller application of about 15cm.

Also, where can I get such a copystand to attach my camera to, so that I can come as close to the coin as possible. That would be so amazing to have one, as my tripod does not go any deeper and that is why I have to elevate the coin. I live in the UK and was never able to find one.

Moreover, I have a huge lighting problem. Is fluorescent light the best I could use. I once heard that a "colder" light bulb such as for reptiles would be the best, but I could not find one of these, as well. I use a conventional horrible desk-lamp with a conventional clear 60W light bulb and always get a horrible red colour which destroys the nature of the coin vastly and takes out to fix at photoshop to only a certain degree.

You also mention "paint bucket". Do you mean the paint bucket from Microsoft Paint which comes with Windows, or some other software. I tried Microsoft Paint and it does only a minute are of the background.

Best wishes,
Burak

Istinpolin:
The image above turned out better, but I have real problems with silver coins, copper is easy but it takes some time at photoshop and constant comparing with the coin in hand, but silver and gold is just horrible for me. Please see a silver coin below with some reddish colour that I could not get rid off without destroying the nature oif the coin.

Burak

Numerianus:
The problem is that  we see coins but also the  coins see us!  An object is visible because it
reflects the light.
I made experiments with a stand: coins are flat and lifeless. Each coin requires an idividual
approach. Rotate the coin to the right or to the left (only to several degrees)  and you can see how the expression of the
emperor will change. You may said: one needs a standard. It is true and not true because each master had his own vision and
and put his own individual imprint. Similarly, the direction of light, deep or shallow shadows do metter.
You cannot compare the coin in hand and on the screen, by many reasons, even because the brain processes these images differently.

Dealers who have a need to handle hundred  at some point decide to take photos  using a stand. I mentioned once the example
of Ancient Treasures.  I enjoyed  their photos when they were  individually adjusted. Now they are standard and ugly.

In fact, I like some  color shadows on  silver: it may be your tee short or furniture. It is quite normal: you look at coins
and coins look at you. 
   

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