FS5: Do you ever shoot at 1/25 shutter speed?

Ivor C

Active member
I've pretty much always followed the double frame rate rule. But on the FS5 even with a speedbooster and fast lens (f1.8) I sometimes want that bit of extra exposure. Thus far I've never gone down to 1/25 shutter speed in 25p, but I was wondering if, and how often, others do?

I get that it won't look as 'filmic', but with so many things getting compressed onto the Net, does it really stand out so much?
 
If you keep your shot locked off, you can mask a great deal of the motion blur that would otherwise make things look a little wonky.

But isn't the FS5 a 3200 ISO camera? I'm a little shocked that with a speedbooster bringing your f/1.8 lens down to an f/1.3 (or so) that you still can't get enough exposure at such a high ISO.

I'd recommend finding an f/1.4 lens to pair with your speedbooster before going to a 360 degree shutter. That'll give you the extra stop without affecting your motion cadence.

And honestly, if something still isn't bright enough at 3200 ISO and f/0.95... just point the light from your phone at it - you'll be able to overexpose it that way!
 
I've pretty much always followed the double frame rate rule. But on the FS5 even with a speedbooster and fast lens (f1.8) I sometimes want that bit of extra exposure. Thus far I've never gone down to 1/25 shutter speed in 25p, but I was wondering if, and how often, others do?

I get that it won't look as 'filmic', but with so many things getting compressed onto the Net, does it really stand out so much?

As Grug says.. as long as the camera isn't moving and your subject isnt moving much you can get away with it.. I have sometimes in past done it for interviews that couldn't be lit and the subject was pretty static.. but otherwise I wouldn't get into the habit of it.. it will look weird in alot of shots..
 
I have no qualms at all about using it whenever I need the light. No one has ever complained and frankly I don't think anyone has ever even noticed it . Always use it for audience shots at a concert or event. Years ago I shot a steadicam scene of someone walking through a city at night and thought if anything would look weird this was it as it was always in motion. Never heard a word from the director. Try it and see if it bothers you. I would almost always prefer a little motion blur to noise.
 
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Same for me.
I do doco most of the time and like to keep the camera ISO as low as possible. Therefore I quite often use 1/25s and I can hardly realize in post where I used it.
If you have a lot of motion involved, you better use 1/50s though.
 
Yes basically fine if not alot of motion.. but personally I think you can see it in alot of circumstances .. so better to stick to 1/50th at 25p.. unless you really need to change.. you can also get rid of some noise in post.. but not motion blur .. my point is that I wouldn't make a habit of it.. and there is a reason for the double frame rate thing.. originally due to an actual physical shutter of course.. but now that look has become the norm and an audience will see something looks odd even if they don't know why..
 
Yes basically fine if not alot of motion.. but personally I think you can see it in alot of circumstances .. so better to stick to 1/50th at 25p.. unless you really need to change.. you can also get rid of some noise in post.. but not motion blur .. my point is that I wouldn't make a habit of it.. and there is a reason for the double frame rate thing.. originally due to an actual physical shutter of course.. but now that look has become the norm and an audience will see something looks odd even if they don't know why..

Audiences change over time and rule books get torn up. Fu*king mobile phones!

I personally prefer 1/25 to doubling the iso but it's all a personal pref. I've shot with even slower shutter at a national trust property that would not allow light in the room to protect some precious murals. We did a lot of still shots and incredibly slow creep zooms which looked OK. This was a long time before denoisers were available.
 
I shoot 1/25 for 24fps and 1/60 for 60fps all the time. If there's a lot of motion maybe avoid it, but otherwise I prefer the less noisy image. I do this more on my Red Scarlet-W vs my FS7 because the Scarlet-W is at around 1 stop less sensitive or maybe a little more.
 
Wow, look at the downvoter. Someone's really got their knickers in a twist. Probably an asshole with all the gear and no idea..
 
I think when you need 1/24th the low light situation itself mitigates the audience being surprised by the slight blur.
 
Im really surprised how many people shoot 360 degree shutter here.. I can really see a difference in alot of cases shooting doc,s.. I would and do, only use it when really necessary for exposure .. its really doesn't look good at all.. dont you have editors and directors complaining down the phone ?
 
Im really surprised how many people shoot 360 degree shutter here.. I can really see a difference in alot of cases shooting doc,s.. I would and do, only use it when really necessary for exposure .. its really doesn't look good at all.. dont you have editors and directors complaining down the phone ?

Out of interest Donny what would your shutter be for 50p and 50i (50 fields)?
 
I never had anybody complaining about it.
If I have a controlled environment, I use the 180 degree rule.

But whenever I need that extra stop, I dial in 1/25s before going up with ISOs. And I don't think it's noticable at all most of the time. It's not a rule for me, it's a creative choice!
 
Im really surprised how many people shoot 360 degree shutter here.. I can really see a difference in alot of cases shooting doc,s.. I would and do, only use it when really necessary for exposure .. its really doesn't look good at all.. dont you have editors and directors complaining down the phone ?

For what it is worth, I was recently doing bts on a feature film and they were shooting with a 210 degree shutter at 24 fps for a scene that involved two characters in a fist-fight with a lot of fast movement. The DP said they were shooting at 210 in order to better sync with some effects strobe lights that were firing off during the scene. I believe that works out to a 1/41 shutter speed. I was starved for light and thus went to 216 degrees, figuring that if 210 was okay for the film then 216 was okay for the bts.

on a related note...

When doing bts I often try to match the production crew's settings. But many times I find my Fs7 starved for enough light to make a healthy exposure and the production crew, on their Alexas, does not appear to be wanting for light. The Alexa is at 800 ISO and an f/2.8 and the image on the monitors looks plenty exposed. I'm cranking up to 2000 ISO on my Fs7, f/2.8 stop, and the image in my Fs7 is still down in the mud and underexposed. What gives? Is it solely the greater dynamic range of the Alexa over that of the Fs7? Or is it also that the light transmission ability of the film crew's expensive glass is that much better than my lowly Canon L glass? I have encountered this even when the film is on one of the big Optimo 24-290mm zooms, not on primes.

If ISO is a measure of the sensitivity of the image sensor, and two cameras are at the same ISO setting, are they not then equally light sensitive outside of lens transmission ability? Or does an Alexa at 800 iso produce a more bright image ( what on film would have been called a more "dense negative" ) than does an Fs7 at 800 iso, even if both cameras are using the same lens at the same t-stop? I guess I am asking if ISO is universal between all camera sensors.
 
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For what it is worth, I was recently doing bts on a feature film and they were shooting with a 210 degree shutter at 24 fps for a scene that involved two characters in a fist-fight with a lot of fast movement. The DP said they were shooting at 210 in order to better sync with some effects strobe lights that were firing off during the scene. I believe that works out to a 1/41 shutter speed. I was starved for light and thus went to 216 degrees, figuring that if 210 was okay for the film then 216 was okay for the bts.

on a related note...

When doing bts I often try to match the production crew's settings. But many times I find my Fs7 starved for enough light to make a healthy exposure and the production crew, on their Alexas, does not appear to be wanting for light. The Alexa is at 800 ISO and an f/2.8 and the image on the monitors looks plenty exposed. I'm cranking up to 2000 ISO on my Fs7, f/2.8 stop, and the image in my Fs7 is still down in the mud and underexposed. What gives? Is it solely the greater dynamic range of the Alexa over that of the Fs7? Or is it also that the light transmission ability of the film crew's expensive glass is that much better than my lowly Canon L glass? I have encountered this even when the film is on one of the big Optimo 24-290mm zooms, not on primes.

If ISO is a measure of the sensitivity of the image sensor, and two cameras are at the same ISO setting, are they not then equally light sensitive outside of lens transmission ability? Or does an Alexa at 800 iso produce a more bright image ( what on film would have been called a more "dense negative" ) than does an Fs7 at 800 iso, even if both cameras are using the same lens at the same t-stop? I guess I am asking if ISO is universal between all camera sensors.

Are you sure that the LUT they are using on Alexa is the same as on your FS7 in terms of how it interprets the underlaying LOG signal's exposure? There are compensating LUT's being used all the time.
 
What Sony calls ISO or EI2000 is nothing of the sort.

In fact even between Sony cameras EI2000 FS7 matched my A7sII at 1250.

Good to know, Ben. I thought ISO was an engineering standard that is the same between all manufacturers and camera models.

To your knowledge, is a T-stop a standard that lens makers follow? That is to ask, is a Leica T 1.8 the same as a Zeiss T 1.8?

Also, how do you chaps know so GD much about video engineering? I read quite a bit online but still feel as if I don't know squat about camera electronics and video engineering compared to you all. :)

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