sorry for stupid question but if i put a 10stop nd filter and a CPL i cant see anything what do you do to find out how much to turn the CPL for example to remove reflections in water?
You need to do is rotate your CPL until you achieve the desired result, then put your 10 stop ND filter in. A 10 stop ND filter is always last to go in after you have set up your composition and adjusted any needed filters as you can't see anything after it is in front of your lens.
That's correct. My approach (noting I've only used mine about 5 times) is below, and any comments/feedback would be welcomed:
1) I scout the shot handheld and then set up. Tripod, cable release, Lee ring & holder, etc.
2) Switch to M, Av, Tv mode -- whatever you prefer. ISO 100*. Always shoot RAW with the Big Stopper -- many have a color shift that you need to back out in post, and RAW gives you a greater ability to do that. For a host of reasons, I switch to manual focus before doing anything. (Forgetting to do this later can burn you when the Big Stopper is in place.) I never remember to do this, but this is where I should
cover the optical viewfinder for the odd risk of light leak.
3) In LiveView, I frame up everything the way I want it. Everything but the Big Stopper
should be in place (CPL, ND Grad perhaps, etc.) and rotated / located the way I want it. I won't get into composition as I'm a rookie on that front, but on the technical side of things, I usually opt to manually focus at 10x zoom 1/3 of the way into the frame as many landscapers recommend.
4) If LiveView is showing me what I want to see in the shot (minus the long exposure the Big Stopper will give me), I write down or remember my aperture and ISO settings.
5) I put my Big Stopper in. My new shutter speed will be whatever I had before times 2^10 = 1024. (Note this is a rough number and that your specific Big Stopper may vary a bit -- you'll learn this as you shoot with it.) You can do the math yourself, read the card that came with your Big Stopper, or just get an ND filter app for your phone.
6) I usually just switch to Bulb mode, but you technically don't have to
if the computed time is under 30 seconds -- you can use M mode then. I input the ISO and aperture from LiveView, and I take the shot with a cable release (in the locked position) and a timer on my phone. I haven't invested in an cable release with a built-in timer, but that is an option as well.
*I'd imagine that you don't always
want 1,024x slowdown and buttery blending. But if you don't have standalone ND filters that are less strong than the Big Stopper, could you cheat and push ISO up to speed up the shot in Step 4, and by extension, take a much shorter final exposure, right? I know jacking up ISO is heresy for a landscape shooter, but it is possible
Feedback appreciated if there is an easier/better way to use the Big Stopper, thanks!