exposure - beginner

[menace3000]

The way I understand it in manual mode one should work like this:
Set ISO to say 100
Set Shutter Speed to say 50
Set F-Stop to what you need aesthetically.
and then adjust exposure by using ND Filters.

Now that´s fine for scenic work, but does not really work for documentary style.

So let´s assume I want use F-Stop 1.4 having just bought a nice Canon FD lens.
Will it really show so much if I adjust exposure by changing the shutter speed?
Or would it be better to try to keep Shutter Speed at 50, and adjust exposure with ISO (up to maybe 800) and then F-Stop, therefore maybe loosing shallow depth of field but keeping Shutter Speed?

Any practical advise would be appreciated.

[Martti Ekstrand]

If in PAL use shutter speed 1/50 unless aiming for slo-mo with 720p50 then use 1/100.

If in NTSC use shutter speed 1/60 unless aiming for slo-mo with 720p60 then use 1/120.

You can deviate from this but bear in mind faster shutter speeds will increasingly yield too little motion blur giving a strobo-scope look to your footage. Of course sometimes that can be a cool effect but mostly it will be distracting. One more effect of going away from these base shutter speeds can be light flicker under fluorescents and sodium lights.

Also having 1/50 or 1/60 shutter speed lessens the 'mud' effect, especially in 1080p due to the motion blur softening the details in the picture when pan/tilting/moving fast.

This is just the nature of the beast when working with moving images. Mostly shutter speed is set at double the frame rate and aperture are kept with-in one step up/down from a base setting. So course exposure is controlled with lighting and ND filters. There are variable ND filters made up with two polarizing glasses. With those you just turn much like a aperture ring. Here's one guy on eBay, I'm sure there are more.

http://shop.ebay.com/merchant/bonifaceleung_W0QQ_nkwZQQ_armrsZ1QQ_fromZ

The ones from Singh-Ray Filters are considered the pro choice but cost a lot more

http://www.singh-ray.com/varind.html

And you can put one linear polarizer and one circular together for a home-made version.

Keeping people in focus at f/1.4 is nightmarishly hard btw. Even if when sitting on a chair and talk - just by rocking back and forward a tinsy bit they will move outside the focus plane.

[menace3000]

Thanks a lot for your advise on this. I will test the effect of shutter speed.
I did not know that there are variable ND filters available.

[menace3000]

I tried the homemade version with two polarizers. Works brilliant, thanks!

[Martti Ekstrand]

If we ever meet the first polar beer is on you.

[menace3000]

That´s a deal then.

Here´s a little test clip, all shot 1.4 with canon 50mm.

http://vimeo.com/5249654

I like the overall feeling and quality but it´s a bit overexposed although the in-camera-meter said minus 1-2. Also it is not really in focus, maybe that´s due to the narrow depth of field, maybe the lens, maybe me... I also set sharpness, contrast -2 which may be good for the stock lens, but for (my) canon it does not seem right.

Cheers.

[Isaac_Brody]

Hey Menace, which polarizers are you using? And is there a way to tell exactly how many stops you're cutting?

[menace3000]

I just went into a camera shop today and bought two second hand filters:
Rowi circular and Marumi P.L. , linear I suppose. No idea whether they are any good, no numbers, they seem to do the job.