[hjoseph7]

i usually buy the B&W stuff, it's highly regarded and has always met my expectations. recently i got me a variable one 1-5 to have more flexibility.
for the type have a look at the table on the wiki it shows what to expect. https://en.wikipedia.org/wiki/Neutral_density_filter

or here: https://www.google.ch/search?q=nd+filter+table&pws=0&biw=1324&bih=488&source...DOaPXtd4-MM%3A

your lenses are light so get a light travel tripod which you can fold small enough


i have the Pentax O-RC1, its water proof and has done a good job.
I also have an IR remote built in my smart phone with the right app and after teaching Pentax i hardly ever take the remote with me and use the phone.

for Catch-In-Focus or trap i use the pentax cable release...

edit: you can use the 2 sec delay for those pics...

+1 on the variable ND filter. No sense fiddling around with a bunch of filters until you get the right light.