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Image enchancement help


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I have got a couple of coins that seems to be very interesting and perhaps pretty scarce if not rare. I have come to a stage realizing that mere constrasting is not enough and I think I will need some help with noise removal and differentation. I do wish that I have a 10mp digital camera or more but that is not an option at the moment ;)

 

I do remember doing something like this on a MathCad but I don't have the software any longer. Would photoshop have a similar function to this? (or is this topic even making any sense to anyone? :ninja: )

 

Or alteratively my last option is to pick up a cheap stereo microscope but that too sounds very expensive.

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You lost me. Exactly what has noise got to do with taking a photo? What differentiation are you talking about? As to a 10 Mega Pixel camera, why. You could use a thousand Meg camera, if one existed, and still have to reduce it for posting on any web site. If your just attempting to take a photo of a coin, there are numerous web sites on how to take coin photos out there. Also, many cheap or free photo programs available by just downloading. For example Picasa is free. I have abaout 5 or more photo programs and one is photoshop and still never even opened it.

www.coppercoins.com has a how to takd photo section. Also, a place called Table Top Studio, coin photography techniques. You don't need a fantastic camera, microscope, etc., you check out the many options available.

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Thanks carl and doug, it's actually not the resolution or detail that is tricky but more to do that the coin itself is corroded that makes it harder to visualize. To be more honest, it's the corrosive nature of the coin that makes it more difficult to visualize.

 

For example:

 

1795ph3.jpg

 

This was shot with a 5mp Ricoh digital camera but at ISO 200 - I don't have enough lighting. I should consider lowering it down to ISO 64 which will help with the noise issue.

 

My idea of image differentiation is to be more selective of how I can pick certain aspects of the design and have a control over to constrast. Constrast might help a bit but it is too generic for what I am trying to exploit. The thing is, I did remember doing something like with on Matlab but unfortunately I don't have the software :ninja: I was kind of hoping someone in this forum would have access to it and help me play around with the images that I have.

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Well after looking at that I assume that what you after is a computer program that can take poor images and enhance them into recognizable objects - kind of like the computers in the movies where they say - "now enhance that". If so, sorry pal - can;t help ya with that.

 

However, after looking at your image, if I had to guess I'd have to guess that it was a counterfeit lion dollar.

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It's actually this coin here GDJMSP, a kopek coin:

 

930426.jpg

 

While I am relatively happy with my camera, I realized that there is a need to go further. Mind you, it might seem like a totally corroded copper coin which is almost worth it's metal value but this particular coin is perhaps more rare than most people who might realize. This seems to be an overstriked coin (I did orientiate it to the underlying crown) but unfortunately I haven't found a systematic method of dealing with such coins. Yes, I might be able to sketch it on paper but it is a lot more trickier than what I expect it to be.

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I think GX is talking about some type of edge detection filter, but there is so many noise in there that it would be better to actually blur the image a bit (or a lot). I have the GIMP at home and i think it might be able to do this.

 

Jose :ninja:

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Ahhhhh what a difference - lions, horses - they're almost the same thing :ninja:

 

Knowing you I figured it had to do with you trying to see an over-strike. But Boy Howdy ! - trying to figure that one out is gonna be tough. But of anybody can do it, it'll probably be you ;)

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Noting the shadowing I'd say you could do a lot better if you took the photos outdoors. On a bright sunny day, but not in direct sunlight, you would get a much better quantity of natural lighting and if in the proper location, no shadows. Digital cameras always work better with a large amount of light and in daylight that is there. I use several digital cameras with different MegPixels and different settings and most always come out the best on a bright sunny day. Also, placing the coin on a dark background will force the camera to consentrate on the coin instead of the background. Try it. Nothing to loose.

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Thanks Carl, most definately there is lighting issue in most of the coins that I take. Should always take good note of it.

 

This is what I am thinking of doing but I guess it is beyond normal standards:

 

http://lakdiva.org/coins/ruhuna/ruhuna_grains_cu.html

 

http://hasyweb.desy.de/science/annual_repo...ib/48/11472.pdf

 

http://www.sciencedirect.com/science?_ob=A...cd9bc335731053c

 

http://www.sciencedirect.com/science?_ob=A...942fb8b3ce61ab0

 

Oh geez, I did forget that I have an account at ScienceDirect, will have to download the articles :ninja:

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