The stadimeter in SH3 wasn't modelled properly... it wasn't a moving line. It was a double-image; they got it right in SH4.
If you had a double image, wave action wouldn't matter as the images would move in tandem, you'll notice that in SH4.
You have 2 choices in SH3...
1) you can turn on the image stabilizer and take a slight hit on realism %
2) or my preferred approach, wait til you have a nice image of the ship in the scope and pause the game. The stad still works while game is paused!
I justify this approach as being acceptable because we're using an unrealistically difficult instrument. Pausing game removes wave action and allows use of stad without realism hit... and I like how the scope moves otherwise.
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