Fingerprint Sensor is discriminating against me

[KhandakeF]

My friend has the Essential phone and I want to put my fingerprint on it (with his permission of course)

 

However, when I try to put my fingerprint, it always always says the scanner is dirty and to clean it. He can do it himself right after with no problem, so the sensor isn't dirty and my finger works on mine so my finger isn't dirty

 

What would cause this type of behavior? This happened before as well

[DezGalbie]

(Just picking a guess right out of the blue here, but...) It seems to me like the phone thinks that the sensor is dirty because it is expecting your friend's fingerprint to be scanned. The scan of your print is being compared to the print of your friend's finger and the phone thinks the discrepancy must be due to a dirty sensor. Like it knows that your print is not his by comparison to the print of his which it already has stored, and so it defaults to assuming the sensor must be dirty and that it has misread the print?

Maybe it wasn't designed with multiple users in mind? I wouldn't expect many phones to be designed with multiple users in mind, TBH. It's usually a pretty personal piece of tech.

[KhandakeF]

7 minutes ago, DezGalbie said:

(Just picking a guess right out of the blue here, but...) It seems to me like the phone thinks that the sensor is dirty because it is expecting your friend's fingerprint to be scanned. The scan of your print is being compared to the print of your friend's finger and the phone thinks the discrepancy must be due to a dirty sensor. Like it knows that your print is not his by comparison to the print of his which it already has stored, and so it defaults to assuming the sensor must be dirty and that it has misread the print?

Maybe it wasn't designed with multiple users in mind? I wouldn't expect many phones to be designed with multiple users in mind, TBH. It's usually a pretty personal piece of tech.

I meant when putting in a new fingerprint, it always says that the scanner is dirty

 

And most phones can store up to 5 prints at a time(that I know of). My print would be the 5th one

[DezGalbie]

1 minute ago, KhandakeF said:

I meant when putting in a new fingerprint, it always says that the scanner is dirty

 

And most phones can store up to 5 prints at a time(that I know of). My print would be the 5th one

Yes, I know that you mean when putting in a new fingerprint.

Maybe I can explain what I mean a bit better.

Maybe there is something about your fingerprint which causes the phone to know that it is not from the same person? You say that this phone already has 4 prints stored. Now what if there is something incompatible about the pattern on your fingerprint and the prints already stored?

I don't know that this is the case, but are there any links between the different prints on the fingers of a hand? Are there similarities between each individual print whereby you can tell that they came from the same hand (or that they could not have come from the same hand)?

Or is it the case that each print for each finger on a hand can just go wild and look like anything, and that a phone could never tell the "odd one out"?

If there is any kind of pattern between prints, or any kinds of disqualifying features which cannot appear together on the same hand, then maybe this has been programmed into the phone?

Where's the CSI guys when you need them? They might be able to answer

[KhandakeF]

1 minute ago, DezGalbie said:

Yes, I know that you mean when putting in a new fingerprint.

Maybe I can explain what I mean a bit better.

Maybe there is something about your fingerprint which causes the phone to know that it is not from the same person? You say that this phone already has 4 prints stored. Now what if there is something incompatible about the pattern on your fingerprint and the prints already stored?

I don't know that this is the case, but are there any links between the different prints on the fingers of a hand? Are there similarities between each individual print whereby you can tell that they came from the same hand (or that they could not have come from the same hand)?

Or is it the case that each print for each finger on a hand can just go wild and look like anything, and that a phone could never tell the "odd one out"?

If there is any kind of pattern between prints, or any kinds of disqualifying features which cannot appear together on the same hand, then maybe this has been programmed into the phone?

Where's the CSI guys when you need them? They might be able to answer

His parents' prints are stored, soooo

[DezGalbie]

Just now, KhandakeF said:

His parents' prints are stored, soooo

Jesus, mate. You're really not even trying to read what I've painstakingly tried to explain. Lol.

His parents prints are stored. Great. That doesn't change the point.

What if there is a feature in your print which the phone knows couldn't have come from the same hand as your friend? His parents prints being stored on the phone really has nothing to do with that question unless his parents have the exact same fingerprints as you, in which case you should forget about the phone problems and put yourselves forward for study by medical science.

But this is just conjecture. I don't know that fingerprint technology is this far advanced yet or whatever. I don't really have anything more to add so I'm unfollowing the thread.

[KhandakeF]

1 minute ago, DezGalbie said:

His parents prints are stored. Great. That doesn't change the point.

What if there is a feature in your print which the phone knows couldn't have come from the same hand as your friend?

If there's a feature in my print that isn't from my friend, how can his parents' prints be there? Since no two prints are alike