I got it upside down, idiot.
Effectively sunglasses. Increase blur. Lots of movement and stillness.
Firstly what is an ND filter well it is effectively
sunglasses for your camera a traditional camera has three ways of being able to
manage the amount of light that comes into the sensor now sensor obviously needs to get
the right amount of light to not be overexposed and not be underexposed and can do that one in
a couple ways one is we can change the iris so when we go outside you notice our eyes close up
and that essentially just reduces the amount of light that can get in now the alternative
way to do that is also to use a shutter so you basically it's the amount of time that the sensor
is exposed to light so if we do it really fast it's a small amount of light if we do it long
a lot more light gets in when you expose an image for a short time nothing moves when you expose it
for a longer time the things that are moving will appear blurred what we're aiming to do is to get
the fast moving stuff like the road blurry so we can see that movement from one frame to the next
and the slower moving stuff in the frame like the bike itself not blurry right so that's why
we use ND filters and the trick is to get the right filter now with traditional cameras they
have the iris so they can close off the amount of light getting in a gopro does not have that the
gopro doesn't have an iris it is basically just the light all gets in now the third piece of that
is iso which is the sensitivity of the sensor the more sensitive it is the more light it can absorb
over a short period of time but it also means that the higher sensitivity you get graininess
in the shot so we want to avoid high iso so when it's bright and sunny like this
what we can do is we put our sunglasses on it reduces the amount of light coming in and
so then we can lower our shutter speed and slow down the shot a bit that's why we use it so the
way this ND filter works is you've effectively got that's the original filter um that goes over
the top of the lens so that just protects the lens it's completely clear we've then got these filters
which then go over the top to replace it and so that's what we're going to do we're going to
start though with this one the naked shot and just show exactly what it looks like without putting
an ND filter on so this is without an ND filter this is a naked gopro straight out of the camera
as I go over those little bits of cracks and the join in the bridge, you can see that's what we're
going to use as a reference point, and you can see basically it is completely still in
the shot it should have, particularly because it's a bright sunny day should be completely
still even when you're trying to demo stuff it's still got to be switched on
So now we're going to swap to an nd8. You can actually do this while you've got the helmet on;
you don't have to turn anything off. We can do a quick swap. Basically, just look in
the mirror so you can see what you're doing. I'm gonna unscrew that so it's a quarter turn
back in the same spot we've got nd8 there, and then also be careful not to scratch your
lens while you're doing this and then we have nd8 see what that looks like so I'm not even
stopping the camera right, so I'm not changing any settings
just keep it rolling all we've changed is the ND filter now having said that settings I'm running
I've actually because it's a bright sunny day and I want to be consistent and just have the
shutter speed adjust itself I've locked the iso down to 100, so I've set the iso max to 100
so both iso max and iso min both set to 100 which means that the iso is locked.
Because we don't have an aperture, so have a look here. We go over the bridge, join the bridge,
and the cracks.
In these two shots, see how they look different. Now we should be seeing a bit of blur
in that join instead. Now, as I said before, the GoPro doesn't have an aperture right,
so it can't close the amount of light down into the iris.
Like a traditional camera does, or as our eyes do,
you can only adjust the light by the shutter. A huge amount of light means that it needs
a really high shutter speed, so putting the ND filter on
it's going to bring allow us to bring that shutter speed back down again, all right
Again not changing any settings, just purely swapping out the filter with the polar pros.
You have the ND symbol pointing to the top click that. One other thing to consider with ND filters
is yes, they are like sunglasses, but you tend to lose a little bit of colour
now; cheap ND filters, I'm not very good with blocking out infrared,
so polar pro is usually pretty good, so again, looking at this join in the bridge.
Now again, we should see then increased blur and lots of movement. ND16 is probably going
to be pretty good. It's also going to be dependent on how much is moving around
in the shot, so if you're on a really bumpy trail out in the dirt,
then this is probably going to be too much because the stabilizer is going to be working pretty hard,
but out on the road you tend to have your head a bit steadier.
Not as much movement, so the stabilizer's not working as hard.
You turning around about that is ambitious.
three-point turner around about
now one thing to consider is as you increase your ND filter, the cheaper
ND filters will really struggle to block out the UV light and that the end result that is
you can end up with a shot that's a bit red, right, because it can't block out all the
colours it blocks out the blues and the greens and kind of leaves a bit of red behind so you end up
a bit of a reddish shade so, of course, you can fix that, but it is hard
The ND 32 is on well, hang on, this is nd8. I got it upside down, idiot.
All right, this is our nd32. Now I suspect it's actually going to be quite dark.
I've got that iso down locked in at 100. all right, so ND,
we're 32 going to see a little too dark
All right, here we go for the great again. We're going over the same spot.
Two downsides to having an ND filter that's too dark. One is the stabilizer gets all
messed up. It needs to see what's moved in each frame, and if everything's all blurry,
it freaks out. Doesn't know what to do. So if you see all this sort of weirdness happening in
the frame where it's all sort of jumping around and being a bit odd, then that's too low light.
The other one is that the ISO will then go up really high,
and the shot will get really grainy, or it'll just be too dark.
The other thing to consider is this is it's an action camera. So when we're
looking at using an ND filter and thinking about the amount of light coming into the camera,
we've got to remember the light changes a lot
while we're riding. You want something that gives you a certain amount of flexibility.
I'm going to switch back to my go-to. It's normally an ND8 but considering it's bright
sunny and not a cloud in the sky, I'm gonna go to an ND16. Which I think is going to be optimal,
so generally, on a day like today, I'd go for an ND16 in the middle of the day and then as the sun
starts to drop, then I'd swap back to an ND8. Then once it gets too dark, then I would go
back to the naked. So pretty much, I run an ND8 as default any time of the day
and then run no filter naked at nighttime.
I hope that helps with ND filters. I hope that gives you some insight if you're thinking about
using them. A key thing to remember if you are thinking about using them is that
you don't want them getting in the way of you having fun. At the end of the day,
you don't want to become a thing where you got to constantly think about it
because it is something that you actually need to think about.
The whole point of what we're doing using an ND filter is to essentially
make it look like we're moving. It just looks more natural, looks more realistic. It's like
bad special effects. You don't really know what's wrong, but you just know something's wrong.