Body: <p>I was using lichess's analysis board for Stockfish's analysis of this line in the French:</p>
  <pre><code>[Title &quot;French Defence, Steinitz Variation&quot;]
  [StartFlipped &quot;0&quot;]
  [fen &quot;&quot;]
  
  1. e4 e6 2. d4 d5 3. Nc3 Nf6 4. e5 Nfd7 5. f4 c5 6. Nf3 Nc6 7. Be3 Qb6 8. Na4
  </code></pre>
  <p>Seeing as this is a familiar line, lichess already had Stockfish analysis to a deep level available in the cloud. After 7 Be3 is played in lichess, it says Stockfish (depth 41) rates 7 ... Qb6 at 0.0,
  giving the line 8 a3 cxd4 9 Nxd4 Bc5 10 Na4 Qa5+ 11 Nc3.
  But if 7 ... Qb6 is then played in lichess, it says Stockfish rates 8 Na4 as +0.6.</p>
  <p>That's a difference of 0.6. That's much greater than rounding error. How come such a large difference? Could it be a horizon effect? If so, it's a particularly distant one! I'd have thought that analysing to depth 41 would give Stockfish plenty of opportunity to reach a quiescent position.</p>
  
Comments.ContentLicense: CC BY-SA 4.0
Comments.CreationDate: 2022-11-05T11:12:29.710Z
Comments.Text: Did you note that once Qb6 is on the board, depth is 47 plies?
Comments.UserDisplayName: Peter Fischer
Comments.ContentLicense: CC BY-SA 4.0
Comments.CreationDate: 2022-11-25T11:00:09.583Z
Comments.Text: Maybe i just do not understand the question. `But if 7 ... Qb6 is then played in lichess, it says Stockfish rates 8 Na4 as +0.6.` -> what is depth for this analyse? I am not near my Stockfish engine but difference 0.6 in the opening (7th move) is not that high imho.
Comments.UserDisplayName: Melkor
Tags: <analysis><stockfish><french-defense>
Title: Are these depth-41 Stockfish evals the result of a horizon effect?
ThreadText: # Are these depth-41 Stockfish evals the result of a horizon effect?
  
  (Asked by: username_0 on 2022-11-05)
  
  I was using lichess's analysis board for Stockfish's analysis of this line in the French:
  
  ```
  [Title "French Defence, Steinitz Variation"]
  [StartFlipped "0"]
  [fen ""]
  
  1. e4 e6 2. d4 d5 3. Nc3 Nf6 4. e5 Nfd7 5. f4 c5 6. Nf3 Nc6 7. Be3 Qb6 8. Na4
  
  ```
  
  Seeing as this is a familiar line, lichess already had Stockfish analysis to a deep level available in the cloud. After 7 Be3 is played in lichess, it says Stockfish (depth 41) rates 7 ... Qb6 at 0.0,
  giving the line 8 a3 cxd4 9 Nxd4 Bc5 10 Na4 Qa5+ 11 Nc3.
  But if 7 ... Qb6 is then played in lichess, it says Stockfish rates 8 Na4 as +0.6.
  
  That's a difference of 0.6. That's much greater than rounding error. How come such a large difference? Could it be a horizon effect? If so, it's a particularly distant one! I'd have thought that analysing to depth 41 would give Stockfish plenty of opportunity to reach a quiescent position.
  
  **Tags:** analysis, stockfish, french-defense
  
  > **Comments:**
  > **username_1**: Did you note that once Qb6 is on the board, depth is 47 plies?  
  > **username_2**: Maybe i just do not understand the question. `But if 7 ... Qb6 is then played in lichess, it says Stockfish rates 8 Na4 as +0.6.` -> what is depth for this analyse? I am not near my Stockfish engine but difference 0.6 in the opening (7th move) is not that high imho.  
  
  ---
  
  ## 0 answers
  
  