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Your picture is amazing. Unfortunately my exposure time can only go up to 15 seconds on the camera I currently use.

Can you use double exposure ? Or try to make two pictures one right after another and then multiply them in photoshop.

I can't do double exposure, but I will try taking to photos and then using photoshop. Thanks.

This might help a little. Just remember, that you have 30sec. time limit. If you will expose longer - you will see stars like short dashes

That helps a lot, thank you.