topic Re: newbie SL3 questions in EOS DSLR & Mirrorless Cameras

newbie SL3 questions

DOUGWOLF — Mon, 23 Mar 2020 19:19:50 GMT

Hello, I am a veteran VFX artist just starting out in shooting video. I have a Canon SL3 and was hoping someone could answer some (I hope) basic questions for me.

1. I have a 50mm lens and an 18-55mm lens and a 55-250mm lens, all Canon. I got a K&F variable ND filter to learn how best to use it in different situations. I found that the filter fits perfectly on the 18-55 and the 55-250, but wont fit on the 50. Am I missing something?

2. When using the 50 mm lens, indoors for video I have very little problem setting the correct Fstop, white balance, ISO etc to get the depth of field and look I want. But when I go outside, everythig is blown out white unless I go to the highest F stop, thus negating any DOF I would want. I have run up and down the scales on ISO, Fstop, white balance, etc and nothing seems to work to get and DOF which I can easily get indoors. Again, am I missing something?

Thank so much for any help.

Re: newbie SL3 questions

kvbarkley — Mon, 23 Mar 2020 19:27:35 GMT

That is the point of the ND filter, to lessen the amount of light getting into the lens to allow for wide apertures in bright light.

You are not giving us enough info to say exactly what lenses you have but a quick glance for typical lenses shows that the 50 mm will have a 52 mm size filter ring while the 18-55 and 50 - 250 will have 58 mm. Filter ring sizes vary all over the place, there is no standard size.

Re: newbie SL3 questions

DOUGWOLF — Mon, 23 Mar 2020 19:39:48 GMT

Gotcha. Thank you for the info.

Re: newbie SL3 questions

rs-eos — Mon, 23 Mar 2020 19:48:20 GMT

A very useful rule of thumb to learn is the 'Sunny 16' rule. On a clear sunny day, an exposure within a proper ballpark is obtained with ISO 100, 1/100 (or 1/125) second, and f/16.

For video, a common setting to use is a shutter that's double the frame rate. Assuming you're shooting at 30 fps, a shutter of 1/60 would be good. So a "video sunny 16" would now need to be at f/22.

In order to open up the aperature, you'd use 3-stop, 6-stop or variable ND as you have. e.g. a 6-stop ND would allow you to open up to f/2.8 (assuming ISO 100 and 1/60 shutter).

For the filter... as mentioned above, filter sizes are all over the map. However, if your 50mm lens works with filter sizes smaller than your K&F ND filter, you can pick up step-up adapters. But this is only when going from small to large; not the other way around. Pros is that you can save some cash. Cons is that such a setup may interfere with lens hoods. May also cause more vignetting.

Re: newbie SL3 questions

DOUGWOLF — Mon, 23 Mar 2020 20:04:15 GMT

Great info! Thanks so much.

Re: newbie SL3 questions

kvbarkley — Mon, 23 Mar 2020 20:11:41 GMT

Pedantic point of order. You want to use a shutter that is *half* of the frame rate, not double. 1/60 is half of 1/30.

Re: newbie SL3 questions

Waddizzle — Mon, 23 Mar 2020 22:40:37 GMT

@kvbarkley wrote:
Pedantic point of order. You want to use a shutter that is *half* of the frame rate, not double. 1/60 is half of 1/30.

If you were shooting at 1/30 shutter speed, and someone said you need to "double your shutter speed", how fast would that be?

Re: newbie SL3 questions

kvbarkley — Tue, 24 Mar 2020 02:07:24 GMT

1/15 of course. If you were at f/11 and someone said, "You need to double your aperture." what would you set it to?

Reciprocals are hard. 8^)

Re: newbie SL3 questions

Waddizzle — Tue, 24 Mar 2020 05:48:45 GMT

@kvbarkley wrote:
1/15 of course. If you were at f/11 and someone said, "You need to double your aperture." what would you set it to?

Reciprocals are hard. 8^)

Shutter speed describes a unit vector. At 1/15 of a second, did you double your speed, or did you double the period?

It I am traveling at 30 mph, doubling my speed would mean traveling at 60 mph. Or, if I were traveling at 30 miles per second, doubling my speed would mean I am traveling at 60 miles per second. Still with me?

At 30 miles per secon, the one mile unit vector is 1/30 of a second. At double the speed, 60 miles per second, the one mile unit vector is 1/60 of a second. Still with me?

Re: newbie SL3 questions

Ray-uk — Tue, 24 Mar 2020 10:46:43 GMT

@kvbarkley wrote:
If someone said, "You need to double your aperture." what would you set it to?

This question only confuses many people because they don't differentiate between aperture and f number. Doubling an f number results in a smaller aperture, doubling an aperture results in a smaller f number.

Re: newbie SL3 questions

rs-eos — Tue, 24 Mar 2020 11:47:29 GMT

Yikes; when I wrote "double the frame rate", I was speaking just to the raw number (30) itself. Double 30 is 60 which led to the 1/60 shutter value.

I guess I should have instead written that a common shutter setting for video is 1 / 2N where N is the frames per second value.

Re: newbie SL3 questions

kvbarkley — Tue, 24 Mar 2020 13:33:57 GMT

Shutter speed is not a rate. It is a straight number of seconds.

What happens when you get to a 2 second shutter speed?

Re: newbie SL3 questions

rs-eos — Tue, 24 Mar 2020 13:44:30 GMT

Why would anyone use a 2 second shutter for video? Also, in all my examples, shutter is _derived_ from the frame rate (24, 30, 60, etc.) Not the other way around. To even get a 2 second shutter, N would need to be 1/2 (half a frame per second).

Dedicated video equipment typically has a shutter angle feature that does things automatically for you. e.g. setting to 180º will set the shutter to always be 1 / 2N no matter what frame rate you're shooting at.

When your equipment doesn't have shutter angle though, and you want to mimic the typical 180º, you take the frames per second value N and set shutter to 1 / 2N.

For 24fps, you use 1/48 (1/50 may be the closest value DSLRs)

For 30fps, you use 1/60

For 60fps, you use 1/120 (1/125 may the closest value on DSLRs)

etc.

Re: newbie SL3 questions

kvbarkley — Tue, 24 Mar 2020 14:18:54 GMT

Sorry, I guess I am bored.

We really need a DSLR/Mirrorless video section of this board to keep the nomenclature straight.

In this case, I would refer to it as a "rule of thumb".

Re: newbie SL3 questions

ebiggs1 — Tue, 24 Mar 2020 15:48:13 GMT

I am glad I never shot video and glad I never will. WHat is hard to understand is why people buy a DSLR and try to make it a video camera. Folks just buy the darn video camera to begin with.

Re: newbie SL3 questions

rs-eos — Tue, 24 Mar 2020 16:08:23 GMT

I do see the appeal to use DSLRs for video. They can work for certain types of scenarios (e.g. interviews, but not long form!) Or, for more cinema style shooting (short takes, limited/controlled camera movement). But for run-and-gun, and more event-driven scenarios, you just cannot beat a dedicated video unit.

Of course Canon (and other vendors) solve the cinema side of things with dedicated units as well (EOS C100 through C700). If money were no object, I've love to own at least a C200.

While I do have a cam to capture family stuff, I'm with ebiggs1 in not wanting to ever shoot video professionally. Way too may variables above and beyond those for stills for my liking.

Re: newbie SL3 questions

Waddizzle — Wed, 25 Mar 2020 10:28:36 GMT

@kvbarkley wrote:
Shutter speed is not a rate. It is a straight number of seconds.

What happens when you get to a 2 second shutter speed?

Two seconds is not a speed. It is an interval of time. Speed is defined as unit of distance per unit of time.

Again, camera "shutter speeds" are actually unit vectors that describe the speed it takes for the shutter to move across the image sensor.

Re: newbie SL3 questions

kvbarkley — Wed, 25 Mar 2020 13:20:17 GMT

whoosh!

The point was not about the nomenclature, but about the fact that we talk about the shutter in terms of straight seconds *and* reciprocals.

Re: newbie SL3 questions

wchettel — Wed, 25 Mar 2020 14:38:39 GMT

The Merriam-Webster definition of 'Speed' is "the magnitude of a velocity irrespective of direction."

Re: newbie SL3 questions

RobertTheFat — Wed, 25 Mar 2020 15:22:48 GMT

@wchettel wrote:
The Merriam-Webster definition of 'Speed' is "the magnitude of a velocity irrespective of direction."

If you're amused by circularity, go look up their definition of "velocity".