View Full Version : video & shutter speed woes


Saif Faris
July 19th, 2014, 06:47 AM
Hello everyone

I did some research & found that the optimal shutter speed 1/50.

Great.
Shot a video with my 5d mkii & 17-40L at f/4 40mm & 1/50.

Turned out good. Smooth enough.

See here:
2015 KTM 500 EXC 6 Days sneak preview - YouTube

As you can see, it right around sunset but exposure turned out.

Today I did another shoot at noon with my 35L.

At iso 100 (apparently Video mode doesn't allow you use the iso 50 option), f/1.6 the camera struggling because it was too bright .
The 1/8000 kept flashing, the camera wanted to stop down to balance exposure.
Finally I stopped down to f/6.3 and that reduced shutter speed to around 1/6400.


Needless to say it was jittery. Movement was shaky.

See here: (2gb file)

https://www.dropbox.com/s/gp5lrqiw2ydpul5/MVI_5847.MOV

Plus, I didn't get to use the aperture i wanted (f/1.6).

So how does one get that cinematic effect bright daylight?

I'm stumped.

Thanks.

Chris Harding
July 19th, 2014, 07:46 AM
Ummmm

Do you know what an ND filter is?? I would suggest you read up on ND's if you want to use big aperture settings.

Saif Faris
July 19th, 2014, 07:50 AM
Hi Chris ,

I'm familiar with ND filters.

But I find it hard to understand that cinematic photography (with dslr's at least) is shot at 1/50 but you need sunset sort of lighting to use wider apertures.

This pretty much rules out photography outdoors the majority the day.


I think there's a missing link somewhere...

Dave Baker
July 19th, 2014, 10:31 AM
Hi Saif,

You're asking for something the camera is not capable of doing. At least not on its own.

To get the correct exposure for a given ISO setting, you must select a suitable shutter speed and aperture to get the exposure value you require, so if you want wide apertures (and why do you want to shoot so wide open anyway?) then you must set a high enough shutter speed to regulate the amount of light hitting the sensor. Conversely, if you want to use a slow shutter speed you must stop the lens down. Either or, sometimes both.

If you can't set the ISO substantially lower and are not prepared to compromise on shutter and aperture settings, then do as Chris says and use ND filters, which you say you are familiar with. DSLRs don't have built-in ND filters like many camcorders, so it's a manual affair. There's plenty of information on the internet, it shouldn't take long to find the information you need

Dave

Saif Faris
July 19th, 2014, 12:42 PM
Hi Dave,

Thanks for the thorough response.

I am very familiar with exposure & the three variables (shutter speed, iso & aperture).

I was just surprised that everyone says shoot at 1/50 & wide open for that cinematic & smooth motion.
But to use a wide aperture (I'm doing a product shoot, so I want to use my Canon 35L or 135L) to get the subject in focus & the background I'm a beautiful creamy bokeh.

But to actually do that, apparently, you need to forgo at daytime shooting.
Or use ND filters. The mind boggling bit is the necessity to use a filter.
I know Lee, Tiffen & B+W are good, but all ultimately degrade quality.

Anyways, I Picked up a Marumi vari nd2-400.

Marumi 72mm 72 DHG Vari ND ND2 to ND400 400 Neutral Density Fader Filter Japan Digital High Grade:Amazon:Camera & Photo (http://www.amazon.com/gp/aw/d/B0065SOI90?pc_redir=1405544324&robot_redir=1)


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About this item
Features
Marumi® brand. DHG Variable ND2 to ND400 Neutral Density Filter.
Steplessly adjust from ND2 to ND400
ND2 to ND400 Exposure Factor : 2 to 400 (1 to 9 F-stops)
Double threaded metal frame
Made in Japan

Noa Put
July 19th, 2014, 06:38 PM
Or use ND filters. The mind boggling bit is the necessity to use a filter.

You say you know about shutter speed, iso & aperture but you can't understand why you cannot shoot at f1.4 in bright daylight without a nd filter? :)

If you don't use a nd filter the only option to compensate for the incoming light to get correct exposure is to ramp up the shutter which will result in other unwanted effects and at very bright sunlight even the highest shutter will barely enable to shoot at f1.4 , that shutter should be at 1/50 if you shoot at 25p in order to get natural looking motion, to keep the shutter at 1/50 you need to use a appropriate ND filter. That's just how it works, there is no way around it to do it right. Actually what you are saying is the same as looking into the sun and not understanding why you need welding glasses to be able to.

Saif Faris
July 20th, 2014, 12:25 AM
Noa,

I should've said I understand the necessity to use nd filters to do the job. Like long exposures a waterfall & all that.

I guess I should've said I'm dumbfounded that till today we have to resort attaching inferior glass to lenses.

I'm from the 'keep it bare' school thought.
I don't use uv or protection filters.
I only use polarizing filters.

I'd have imagined they'd come up with something now.

But that's besides the point.

I did pick up the Marumi & will report back with my findings.