why 160, 320,640 ISO for video recording

I've watched philp blooms video, and he mentioned that he always record in 80,160,320,640 ISO.... but WHY?

also for shutter speed set to 50 at 24p, but why double the numer?

Generally ISO 160 is cleaner noise than 100 and 320 is cleaner than 200, etc. Proof: http://petapixel.com …when-shooting-dslr-video/

If youre shooting in 24 fps, shutter speed must be 1/50 because it allows the perfect amount of motion blur to give you a cinematic film look. The exposure time is supposed to be half of the frame rate, as with traditional film recording. 1/24 doesnt exist, and turn it up to 1/500 for ex and not only do you lose a ton of light but you'll see that there's NO motion blur and so everything is overly crisp and digital looking (people moving look very choppy and harsh cause of how fast the shutter is recording). If you're shooting 60p for slo-mo, shutter speed must be double (1/125).

These are rules of thumb in digital video, follow them.

For more info, read:
http://www.dvinfo.net …-speed-always-double.html
http://photography.tut​splus.com …affect-video--photo-12092

My understanding is the 160 base ISO is using the purest processing through the system. Alternative speeds are 160 boosted or reduced as required. As noted above both versions have the capacity to add noise.

I've not done back to back tests but 160/320/640 gives a fair range so I don't see the point of not using them when, those who know, all say it is the best option.

Canon 7D and 5D were tested by a few sources to have the least noise at their native ISOs which were 160, 320 and 640. 1250 doesn't fare as well due to the fact this is considered a "high" ISO for APS-C, plus it seems to be an amplified value and not truly native.

I assume this would mean the 6D and most Rebels hold the same native ISO values as many have the same sensors.

thedcmule2 wrote in post #16718068
If youre shooting in 24 fps, shutter speed must be 1/50. If you're shooting 60p for slo-mo, shutter speed must be double (1/125).

"must be" is a strong statement, and one of the reasons a lot of people don't progress with video beyond cookie cutter run of the mill videos. When you start to really understand how the shutter speed effects your video rather than just assuming it has a set value, then it opens up a lot of creative opportunities.

I have been filming professionally for half a decade, I know what im talking about. There's no "creativity" involved with other shutter speeds on Canon DSLRs, we're talking about video not stills. The only other thing I can think of is extremely high shutter speeds for Twixtoring or massive slow-mo, which doesn't really look that good on Canon DSLRs but I guess you can use it. If you shoot video as much as I do you'd know this, but please enlighten me on what creative opportunities other shutter speeds have done for you...

thedcmule2 wrote in post #16737158
I have been filming professionally for half a decade

Time spent doing video doesn't mean a lot in this industry. I know a lot of long running production companies that make terrible videos.

Anyways, Shane Hurlbut, the DP for Act of Valor, the film that was shot almost entirely on Canon DSLR's is quoted saying that he used alternating shutter speeds to customize the look of certain shots in the film that would go against the 180 degree "rule". For example 30fps 1/50 or 1/40 (never 1/60) and he also recommends 60fps 1/100.

Yeah but thats not really opening a can of creativity as you claim. But I get your point, you can -slightly- customize the sharpness of motion through differentiating those speeds. I wasnt holding a gun to anyones head when I said the speeds "must be" something, OP seems to be new to video so thats why I gave him rules of thumb. Once he understands them he can go off and do whatever the heck he wants after.

Kento wrote in post #16737374
....look of certain shots in the film that would go against the 180 degree "rule". For example 30fps 1/50 or 1/40 (never 1/60) and he also recommends 60fps 1/100.

So increasing the effect of blur rather than, as some might (and look horrible as a result) reduce blur through higher shutter speeds. More 180 rule but more so.

John Sims wrote in post #16738166
So increasing the effect of blur rather than, as some might (and look horrible as a result) reduce blur through higher shutter speeds. More 180 rule but more so.

I agree, when most of us think high shutter speed we think "ugh, horribly sharp digital look", but when we label it as "horrible" it makes many people assume that it must be BAD to have this look, and to avoid it at all costs!

Let's say im making a short film, and in this film I have in the script that I want some "home movie" footage to play as sort of a flashback for one of the characters developement scenes. I could either A: Find or Buy an actual Handycam for the "horrible" looking digital video, or B: Use a high shutter speed on the 5D that im already using to shoot the entire short film and add grain and color in post to make it look like a Handycam. Creative use of shutter speed ftw.

Lol wow...you ooze creativity

thedcmule2 wrote in post #16739424
Lol wow...you ooze creativity

cre·a·tiv·i·ty

the ability to transcend traditional ideas, rules, patterns, relationships, or the like, and to create meaningful new ideas, forms, methods, interpretations, etc.; originality, progressiveness, or imagination

https://vimeo.com/1587​5333

this is an interesting test on vimeo (not mine), I know "rules" is a dirty word but the multiples of 160ISO seems like a good "guideline" to follow if you are at all interested in image quality

Kento wrote in post #16739604
cre·a·tiv·i·ty

the ability to transcend traditional ideas, rules, patterns, relationships, or the like, and to create meaningful new ideas, forms, methods, interpretations, etc.; originality, progressiveness, or imagination

Dont give yourself that much credit

thedcmule2 wrote in post #16739629
Dont give yourself that much credit

I only fit part of that definition; originality, progressiveness, or imagination are definitely up for debate