A really noob question about focal length.

[Fotografer]

<b><font face="Arial">I have a really noob question (idiotic even) but it had been bothering me for a while now...</font></b></p>
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<p><b><font face="Arial">Okay. Now, I know I didn't have the budget for a 500mm lens, but I have a 300mm + 1.4TC do the focal lenght is 420mm.</font></b></p>
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<p><b><font face="Arial">So if I took a step forward from point A to point B, and lets say the step is 80mm total, then shoot the picture. Is that equivalent to shooting a subject in point A with a 500mm lens?</font></b></p>
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