user30282: I wish to know how to handle a certain situation regarding chess etiquette. Consider the following:
I went for an OTB tournament recently - rapid 15 + 10 time control. Organizers stated that recording is not compulsory, but I still recorded for the purpose of post-mortem analysis. One of my opponents didn't record the game himself but he asked me for a photo of my recording sheet after the game ended, which I had recorded on my own time during the game.
Should I let him take a photo or ask him to record his game himself if he wants to do post-mortem analysis? I let him take a photo but I feel a bit sour now, considering that it's pretty unfair that I spent some of my own time recording instead of thinking - or am I being a bit petty? Also we'll probably meet in some other tournament again just that he's in a better position to prepare against me now.

user31921: This is too long for a comment, but Brian Towers answer as it currently stands is legally wrong. It is true that the score sheets are property of the organizers. But the document you wrote during the game is not a score sheet as understood by the rules, these are just your personal notes that happen to have a form that is very similar to a score sheet.
Score sheets have to satisfy a whole bunch of rules on what is and isn't written there, how it is written and which notation has to be used. Your personal notes are not bound by any of these rules. You could have skipped a few moves, you could have written down some variant that wasn't actually played in the game, you could have used your personal notation, maybe you didn't even write down the game at all but rather some general impressions of the tournament. All of these things would get you in trouble on an official scoresheet. None of them matter on your personal notes.
What you wrote are your personal notes and you are free to do with them as you please.
All that being said, personally I would consider it impolite to not share them if the other player asks nicely. This is just information, you lose nothing by sharing but the other player gains something.

user19861: You dont have any obligation. If I was playing a friend I would give it to them but if I thought he was doing it to gain an advantage, which he is by forcing you to use your time, I wouldn't.
He is choosing to not record the game. If you give it to him its a favor.
Besides, how does someone not remember the game they just played? Thats just laziness. Back in the day, before smartphones and before I had internet, I would go down to the local library and play online for 4-5 hours then come home and transcribe the 10-15 most interesting games. How can someone not remember ONE game they just played?

user13012: This is an incredibly legalistic argument over a simple matter of common decency. Rules have no place here. Use your common sense and be as nice to your opponents as they are to you.

user14340: It seems likely that someone who doesn't record moves themselves wants a picture for personal gratification ['my first chess game in a real tournament!!!'], rather than deep study for which they maliciously offloaded work to you.
Therefore refusing a picture of this is not a matter of some sort of 'game edge' you are denying, it is simply a personal request which provides no harm to you and some enjoyment to the other player.

user4418: 
Should I let him take a photo or ask him to record his game himself if he wants to do post-mortem analysis?

The FIDE Laws of Chess say this about the ownership of the scoresheet:

8.3  The scoresheets are the property of the organiser of the competition.

and they say this about sharing the scoresheet:

8.5.2    If only one player has not kept score under Article 8.4, he must, as soon as either flag has fallen, update his scoresheet completely before moving a piece on the chessboard. Provided it is that player’s move, he may use his opponent’s scoresheet, but must return it before making a move.

So, you are not allowing your opponent to take a photo of your scoresheet, you are allowing your opponent to take a photo of the organiser's scoresheet for your game and there are certain events which can happen during the game which require you to share the scoresheet you are keeping.
Although the rules are silent on what happens after the game regarding sharing the scoresheet it would appear churlish to deny your opponent a photo. Arguably your opponent needs the permission of the organiser, the owner of the scoresheet, not you, in order to make a copy.

user27380: You did the right thing! I would definitely allow my opponent to take a picture of the scoresheet. There is no need to be sour, as it is very unlikely you had or will have any disadvantages from his behaviour.
It was your choice to spend time recording the moves and one single game will not help him in a meaningful way to prepare against you next time, even if he didn't have ChessBase. Even if it did, you would still need to be matched.
Of course, it would not have been sportsmanlike if he had already started to record the moves and stopped doing that after noticing you keep recording the moves only in the hopes of getting them from you later. In this case, rather than alleging that so. has such dishonest motives, grant him the benefit of the doubt and show magnanimity.
In the case described, I would assume that he would not have recorded the moves anyway and only asked for the sheet because it was nice to have.
Try to separate your emotions about the game itself from such questions.
I find it hard to believe that you would have such thoughts if you had taken the full point effortlessly.
If that player does not already have a reputation for taking advantage of others, I will second Brian Towers' opinion that refusing the scoresheet would appear rather petty.

30282: <p>I wish to know how to handle a certain situation regarding chess etiquette. Consider the following:</p>
<p>I went for an OTB tournament recently - rapid 15 + 10 time control. Organizers stated that recording is not compulsory, but I still recorded for the purpose of post-mortem analysis. One of my opponents didn't record the game himself but he asked me for a photo of my recording sheet after the game ended, which I had recorded on my own time during the game.</p>
<p>Should I let him take a photo or ask him to record his game himself if he wants to do post-mortem analysis? I let him take a photo but I feel a bit sour now, considering that it's pretty unfair that I spent some of my own time recording instead of thinking - or am I being a bit petty? Also we'll probably meet in some other tournament again just that he's in a better position to prepare against me now.</p>
 31921: <p>This is too long for a comment, but Brian Towers answer as it currently stands is legally wrong. It is true that the score sheets are property of the organizers. But the document you wrote during the game is not a score sheet as understood by the rules, these are just your personal notes that happen to have a form that is very similar to a score sheet.</p>
<p>Score sheets have to satisfy a whole bunch of rules on what is and isn't written there, how it is written and which notation has to be used. Your personal notes are not bound by any of these rules. You could have skipped a few moves, you could have written down some variant that wasn't actually played in the game, you could have used your personal notation, maybe you didn't even write down the game at all but rather some general impressions of the tournament. All of these things would get you in trouble on an official scoresheet. None of them matter on your personal notes.</p>
<p>What you wrote are your personal notes and you are free to do with them as you please.</p>
<p>All that being said, personally I would consider it impolite to not share them if the other player asks nicely. This is just information, you lose nothing by sharing but the other player gains something.</p>
 19861: <p>You dont have any obligation. If I was playing a friend I would give it to them but if I thought he was doing it to gain an advantage, which he is by forcing you to use your time, I wouldn't.</p>
<p>He is choosing to not record the game. If you give it to him its a favor.</p>
<p>Besides, how does someone not remember the game they just played? Thats just laziness. Back in the day, before smartphones and before I had internet, I would go down to the local library and play online for 4-5 hours then come home and transcribe the 10-15 most interesting games. How can someone not remember ONE game they just played?</p>
 13012: <p>This is an incredibly legalistic argument over a simple matter of common decency. Rules have no place here. Use your common sense and be as nice to your opponents as they are to you.</p>
 14340: <p>It seems likely that someone who doesn't record moves themselves wants a picture for personal gratification ['my first chess game in a real tournament!!!'], rather than deep study for which they maliciously offloaded work to you.</p>
<p>Therefore refusing a picture of this is not a matter of some sort of 'game edge' you are denying, it is simply a personal request which provides no harm to you and some enjoyment to the other player.</p>
 4418: <blockquote>
<p>Should I let him take a photo or ask him to record his game himself if he wants to do post-mortem analysis?</p>
</blockquote>
<p>The <a href="https://handbook.fide.com/chapter/E012018" rel="noreferrer">FIDE Laws of Chess</a> say this about the ownership of the scoresheet:</p>
<blockquote>
<p>8.3  The scoresheets are the property of the organiser of the competition.</p>
</blockquote>
<p>and they say this about sharing the scoresheet:</p>
<blockquote>
<p>8.5.2    If only one player has not kept score under Article 8.4, he must, as soon as either flag has fallen, update his scoresheet completely before moving a piece on the chessboard. Provided it is that player’s move, he may use his opponent’s scoresheet, but must return it before making a move.</p>
</blockquote>
<p>So, you are not allowing your opponent to take a photo of <em>your</em> scoresheet, you are allowing your opponent to take a photo of the <em>organiser's</em> scoresheet for your game and there are certain events which can happen during the game which <em>require</em> you to share the scoresheet you are keeping.</p>
<p>Although the rules are silent on what happens after the game regarding sharing the scoresheet it would appear churlish to deny your opponent a photo. Arguably your opponent needs the permission of the organiser, the owner of the scoresheet, not you, in order to make a copy.</p>
 27380: <p>You did the right thing! I would definitely allow my opponent to take a picture of the scoresheet. There is no need to be sour, as it is very unlikely you had or will have any disadvantages from <strong>his</strong> behaviour.
It was your choice to spend time recording the moves and one single game will not help him in a meaningful way to prepare against you next time, even if he didn't have ChessBase. Even if it did, you would still need to be matched.</p>
<p>Of course, it would not have been sportsmanlike if he had already started to record the moves and stopped doing that after noticing you keep recording the moves <strong>only in the hopes of getting them from you later</strong>. In this case, rather than alleging that so. has such dishonest motives, grant him the benefit of the doubt and show magnanimity.
In the case described, I would assume that he would not have recorded the moves anyway and only asked for the sheet because it was nice to have.</p>
<p>Try to separate your emotions about the game itself from such questions.
I find it hard to believe that you would have such thoughts if you had taken the full point effortlessly.
If that player does not already have a reputation for taking advantage of others, I will second Brian Towers' opinion that refusing the scoresheet would appear rather petty.</p>
