PHD problem

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pedro.m.reis

Newbie but eager to learn
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Hi ppl.

A friend of mine is getting a PHD on passive iris recognition.
He talked to me because he is having a problem on obtaining "passive" iris images.
The gold is getting an image of the iris at distance....
Lets assume that the subject is still, or almost still (think on a subject that is sitted on a train or airplane trip), and light is optimal or near that.
Is it possible to take a picture of the head/face and then get (by cropping) an image like those i'm showing here?
I cannot get that kind of detail with my gear at distance , but, i'm a poor guy :).
There are 2 images, the "good" one is 400x300 the "minimum" quality one is 200x150.
Your thoughts and examples are very welcome.

Thanks
 

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Medium format is best for that kind of thing... unfortunetely my scanner is really poor. I once took a photo, on which I could see myself and the camera reflecting on a tiny light on an eye...
 
I think that a Dslr with a ring light is what you're after.
 
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The gold is not macro/close range foto. That we can acheive with an inexpensive p&s camera ... Those in example where taken with one.
The gold is getting that detail at some distance, like 4-6mts, with a "face" shot.
Offcourse that the only way to go is digital....
 
Does passive mean there is no operator who can zoom in? If that is the case I would try to position the camera in a place the people have to walk by to get them in a controllable environment. Like the exit areas of the train. There is not enough room to pass the camera unnoticed. But then there is the size of the people which has to be taken into account. Not easy and if it leads to more big brother stuff it is ... well ... not desirable
 
Hey! i'm looking for a gear setup, not the M.O. for getting the pictures :D
The problem ist that we cannot get enough detail to get a readable iris at distance....



MichaelB said:
Does passive mean there is no operator who can zoom in? If that is the case I would try to position the camera in a place the people have to walk by to get them in a controllable environment. Like the exit areas of the train. There is not enough room to pass the camera unnoticed. But then there is the size of the people which has to be taken into account. Not easy and if it leads to more big brother stuff it is ... well ... not desirable
Click to expand...
 
Passive means without the subject participation (in some degree).


MichaelB said:
Does passive mean there is no operator who can zoom in? If that is the case I would try to position the camera in a place the people have to walk by to get them in a controllable environment. Like the exit areas of the train. There is not enough room to pass the camera unnoticed. But then there is the size of the people which has to be taken into account. Not easy and if it leads to more big brother stuff it is ... well ... not desirable
Click to expand...
 
Sorry, but as I see it the placement should be clear to chose the gear. If it is a small place to cover you can use a normal digital with "wide" lens. If you have to be far away you need a zoomlens with much more mp. So my solution would be a small area to cover to be able to use a wide lens and do the cropping for the iris. If there is an operator and you have the space try a normal dslr with a zoomlens. Other than that I can not recommend anything special.

Edit:
I just searched for an example. 5mp with the subject about 5m away will not provide good enough results. I would look for a +10mp and a good zoomlens (maybe 200mm?) digital. A modern superzoom?
 
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Yes, maybe a superzoom.
I was hopping for some examples since buying a 200mm lens + DSLR "just for trying" is not an option.....
The best result we had with a 5Mp p&s where close range, at max distance of maybe 50cm. I beleive that a "pro" lens may give good enough results at 5-6m, with a 8-10MP DSLR. But i've searched the "net" for an exemple without luck, hence the post here.
Thanks


MichaelB said:
Sorry, but as I see it the placement should be clear to chose the gear. If it is a small place to cover you can use a normal digital with "wide" lens. If you have to be far away you need a zoomlens with much more mp. So my solution would be a small area to cover to be able to use a wide lens and do the cropping for the iris. If there is an operator and you have the space try a normal dslr with a zoomlens. Other than that I can not recommend anything special.

Edit:
I just searched for an example. 5mp with the subject about 5m away will not provide good enough results. I would look for a +10mp and a good zoomlens (maybe 200mm?) digital. A modern superzoom?
Click to expand...
 
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