# hole card question

• SilentBob420BMFJ

hole card question

the casinos in my area use the mirror reader, and a while back i was staring at the black plastic of it, right where it meets the mirror, and when the dealer slid her card in, all i could see was white.. well, i thought it wasnt working, but then i found out (i cant believe i didnt notice before) that all 2-9 cards dont have the number in the corner of the card, but rather about a 1/2 inch down from the corner, so as to avoid dealer player collusion.. so i realized that i did in fact see the card, it just was a 2-9, well i thought that well, it dont matter if i can see it, because if i can see the card, then the dealer will have blackjack, and i wont be able to use that information..

well it just hit me, if the dealer has a TJQK, and checks for blackjack, i could still see another TJQK! and according to the knockout book, if a dealer shows a ten, he will have another ten under there 55% of the time, which means 55% of the time he has a ten showing, and checks for blackjack, and doesnt have it, then i will be able to hit my 17-19s or not double down on any of my hands! im wondering what kind of advantage would you have if you knew ONLY if a dealer had 20 (not A9 tho) but not any other hand..

i cant believe they make the black plastic on the mirror readers shiny.. im thinking, if the dealer has a ten 31% of the time (more than that if you only play in positive counts like i do), and she has another ten under that ten 55% of the time, this would mean i would know the dealers hand on approximately 18% of ALL hands! the problem is, the dealer would have a 20, which you cant really win against anyways, but i could avoid doubles, which would help variation and save me money, and i could hit my 17,18,19.. so are we talking a nice advantage here?

• 21forme

If a dealer shows a ten, has checked the hole card, and doesn’t flip an ace, the chance of another ten is 4/12 (assuming infinite shoe) or 33%. Where does 55% come from?

• Brock Windsor

Your percentages are wrong Bob but your instinct is correct. Knowing every time the dealer has a 10-10 20 would give you an advantage, more so with surrender. Do not double nor split if you know the dealer has 20. Im surprised you were able to spot hole cards in this manner as any table layout/cards I’ve seen wouldn’t lend itself to players seeing the mirrored reflection.
BW
p.s. 10’s are 4 in 13 with an infinite deck and better than 4 in 12 with a TC+3

• Canceler

Seems unlikely

Quote: SilentBob420BMFJ said:
well it just hit me, if the dealer has a TJQK, and checks for blackjack, i could still see another TJQK!

Have you ever actually done this?

Related question: Do the aces have an “A” in all four corners?

When checking for an Ace,the card is not inserted the same way.Its at a 90% different angle.

• Brock Windsor
When checking for an Ace,the card is not inserted the same way.Its at a 90% different angle.

Hence my surprise he could spot TJQK, or even see anything. The Aces in that deck would need a raised A as opposed to being custom marked in the opposite corner. Perhaps this was just theory and not practice

• SilentBob420BMFJ
Quote: 21forme said:
If a dealer shows a ten, has checked the hole card, and doesn’t flip an ace, the chance of another ten is 4/12 (assuming infinite shoe) or 33%. Where does 55% come from?

the knockout blackjack book says if the dealer has a ten, he has a 55% of getting a 20, so ya, i forgot that would include T55, T28, T226 and such

Quote: Brock Windsor said:
Your percentages are wrong Bob but your instinct is correct. Knowing every time the dealer has a 10-10 20 would give you an advantage, more so with surrender. Do not double nor split if you know the dealer has 20. Im surprised you were able to spot hole cards in this manner as any table layout/cards I’ve seen wouldn’t lend itself to players seeing the mirrored reflection.
BW
p.s. 10’s are 4 in 13 with an infinite deck and better than 4 in 12 with a TC+3

they arent MY percentages, its from the blackjack book, but i somehow misunderstood, read above.. i cant see the mirror, its very hard to explain, but the black plastic is shiny and reflective, so i can see off of that, but all i could see was white when he inserted the card, which would mean i saw the card

Quote: Canceler said:
Have you ever actually done this?

Related question: Do the aces have an “A” in all four corners?

im not sure, what are you getting at?

When checking for an Ace,the card is not inserted the same way.Its at a 90% different angle.

what do u mean? im sure all casinos use the same mirror reader, where the dealer takes the card and inserts the bottom right of the card (the short sides of the card face the dealer and you) into the reader, ive never seen them put the card in sideways (short sides face 1st and 3rd base) or anything, so i dont know what you mean, especially when you say “90% different”

Quote: Brock Windsor said:
Hence my surprise he could spot TJQK, or even see anything. The Aces in that deck would need a raised A as opposed to being custom marked in the opposite corner. Perhaps this was just theory and not practice

now im getting confused, i guess i should take a look at the ace and compare it to TJQK, but no, i have never actually seen a card in the reader, just that one time the reflection i saw white when he put the card in, proving i saw the card, because it was just black when the card wasnt in there.. but im guessing there is a way to make it so when you check for blackjack with an A, the dealer wont be able to see if there is another A under there, which i think he would be able to see that, but im probably wrong, and the same goes with 2 tens, because i thot that AKQJT all have the letters placed in the exact same place, and the 2-9 is .5 inches down

• ihate17

How and why of most readers

The idea is two fold. Stop spooking and tells.

When the dealer has a ten card showing he slips the card straight into the reader and sees nothing unless there is an ace in the hole for blackjack. This way, there are no tells from the dealer that might let a player know he is stiff or has a 20.

When the dealer has an ace showing the hole card is inserted at a 90 degree angle and if the hole card is not a ten, the dealer again sees nothing.

Sometimes there is some wear or something faulty in the reflective area and that might create a situation where you or the dealer can see something you should not be able to see.

ihate17

• Canceler

Disclaimer: 99% of my experience has been with the red light/green light system. I can explain how that works!

I’m 100% sure that when the dealer checks for BJ he knows if he has one, and if he doesn’t, he doesn’t know what the hole card is. And I was going to explain exactly how that’s done, but now I can’t figure it out myself.

Quote: SilentBob420BMFJ said:
im not sure, what are you getting at?

My question about the A in all four corners was not meant to be a trick question. I played at one place with cards like that.

Quote: SilentBob420BMFJ said:
now im getting confused, i guess i should take a look at the ace and compare it to TJQK

Yes, do that. And report back.

Quote: SilentBob420BMFJ said:
but im guessing there is a way to make it so when you check for blackjack with an A, the dealer wont be able to see if there is another A under there, which i think he would be able to see that, but im probably wrong

So, SilentBob, why don’t you go to the casino and find out just how this works. Ask the dealer to explain it if you have to. (If you can explain it to me, I’ll think of you as a genius for at least 15 minutes.)

Or, if someone else wants to explain it before he gets a chance to, that’d be fine.

• Brock Windsor
Quote: Canceler said:
Disclaimer: 99% of my experience has been with the red light/green light system.
Or, if someone else wants to explain it before he gets a chance to, that’d be fine.

I’ve never played redlight/greenlight. Aces have a marking in the upper right hand/lower left hand corner when the card is face up, that is why turning the card 90 degrees allows checking for BJ with a 10 up. 10 value cards have their numerical ranking printed higher than cards valued 2-9 + A. That is how a dealer can tell if he has BJ with an ace up, but can not tell what the value is if the hole card is not a ten.
BW

• Canceler

Ah, now I get it. Thanks, BW!

• SilentBob420BMFJ
Quote: Brock Windsor said:
I’ve never played redlight/greenlight. Aces have a marking in the upper right hand/lower left hand corner when the card is face up, that is why turning the card 90 degrees allows checking for BJ with a 10 up. 10 value cards have their numerical ranking printed higher than cards valued 2-9 + A. That is how a dealer can tell if he has BJ with an ace up, but can not tell what the value is if the hole card is not a ten.
BW

im pretty sure the ace is in the same position as the tens, its just that its in opposite corners, because if the A was in the same position as the 2-9, you couldnt see it regardless of how you inserted it

• Brock Windsor
Quote: SilentBob420BMFJ said:
im pretty sure the ace is in the same position as the tens, its just that its in opposite corners, because if the A was in the same position as the 2-9, you couldnt see it regardless of how you inserted it

It is not usually the A the dealer looks at. There is a marking on the face of the card at the opposite corner on aces, that is why the card is turned 90degrees and that is how the dealer checks for BJ with a 10 up. Instead of that marking I suppose the A could be raised and printed on the opposite side, I just haven’t noticed decks like that. I normally play Bee no.92 cards. Find out what your casino is using.

• Canceler

Or is it complete confusion?

Just for completeness, and while hoping not to add to anyone’s confusion…

Just last night I saw another way of doing this. The 2-K were all printed low, with the A being the only one printed high. The 10-value cards were the ones with the mark in the opposite corner. It ends up working exactly the same way as has been described, though.

• SilentBob420BMFJ

ok i went to the boat and here is what i found.. all the cards except for the tens have the letter/number in the exact same place (for instance, some casinos have it so the A is in the top left and bottom right, and then the tens would be the opposite of that, in the top right and bottom left, but resorts doesnt do that), which is a half inch from the top, in 2 corners of the card, but the aces also have a tiny resorts logo in the other corners, and the dealer told me he sees the logo when he checks under a 10 for a bj.. so if hes checking for a ten, he will see it because its at the top of the card, and if hes checking for an ace, but there is another ten underneath, he will see nothing, because there is nothing in the corners of the other cards where the ace normally has the resorts logo.. but im thinking, the dealer must turn the card if his up card is a ten, because otherwise he would either see nothing, or a ten underneath, but i could swear i saw him checking for an ace underneath the same way he checks for a ten underneath..

• beat320

sigh… if only casinos started using Bicycle Poker Peek© Playing Cards for blackjack games

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