Long exposure help?

[Danny_511]

Im looking into doing long exposure photography. Stuff like blurred people walking in the city and the bridge and skyline at night. Sorry thats not a good explanation but im at a loss for words right now lol. During the day I know I'd need a Nd filter but, im not sure which kind. What would you recommend?

 

[smenkhare]

I use a Hoya NDX400

 

[TCookieMonster]

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