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Guide to SL video


Big John

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Because if you're footage has a capture rate different to your system type (NSTC and PAL have different rates) or to your monitors refresh rate it can show up as jittery footage. It's mostly about keeping the frame rate consistant through the whole imaging pipeline. Often multiples or fractions (1/30 and 1/60 or 1/24 and 1/48) will sync up just fine.

 

Remember the old days of film, when wheels looked like they were spinning backwards. That's the same kind of thing. Just with film (which is 24fps).

 

Gordon

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Thanks.  Will try that but to be honest I don't understand how shutter speed plays into movies?

 

Try shoot something at let's say 1/60th then at a shorter exposure time and compare . Or just tell us in detail the specs of the stuff that gives you trouble in the first place, we might be able to answer  your query more appropriately.

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Because if you're footage has a capture rate different to your system type (NSTC and PAL have different rates) or to your monitors refresh rate it can show up as jittery footage. It's mostly about keeping the frame rate consistant through the whole imaging pipeline. Often multiples or fractions (1/30 and 1/60 or 1/24 and 1/48) will sync up just fine.

 

Remember the old days of film, when wheels looked like they were spinning backwards. That's the same kind of thing. Just with film (which is 24fps).

 

Gordon

 

Yes thanks, am aware that this is the issue. The 120fps plays beautifully smoothly on iPad. 

Is there anywhere that shows which frame rate is best for TV or Mac or iPad?  I could also do with a guide on what the pixel frame sizes mean too?  Any ideas pls. Thanks. 

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Yes thanks, am aware that this is the issue. The 120fps plays beautifully smoothly on iPad. 

Is there anywhere that shows which frame rate is best for TV or Mac or iPad?  I could also do with a guide on what the pixel frame sizes mean too?  Any ideas pls. Thanks. 

 

 

Via the power of Google I have found several sources that show me how little I know about filming video!!  Anyway, at least I can now  understand the theory and will be able to get a lot more from my SL!

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Ok, am making real progress understanding video capture - it is not something I have used much in digital so apols for all the basic questions earlier.

 

Off on vacation soon and keen to find a setting that I know will produce at least acceptable quality to review when home. One thing I am yet to understand is the AII and PBB format settings (think they are correct - don't have my camera with me). Anyone help pls? Thanks.

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I'm not familiar with the SL specifically, but I've got some experience with video shooting.

 

Generally, set the shutter speed to be twice the inverse of the frame rate.  E.g., when shooting at 25p, use 1/50th shutter speed.  In 30p, use 1/60 shutter speed.  For the high frame rate 120p footage, try to get a 1/240 or 1/250 shutter speed.  This is known as a a 180" shutter, and provides the same kind of motion blur that you see in movies and television. 

 

If you make the shutter speed faster, the footage will look more choppy.  Faster shutter speeds are often used in movie action sequences to give the illusion of faster action, like the battle scenes in Saving Private Ryan.  Make the shutter speed slower and the footage will be more blurry.  Try it and you'll see what I mean.

 

There will be times when a shutter speed using the 180" rule results in overexposed footage, or footage that isn't bright enough.  For example, say you're shooting in 25p and you have a shutter speed of 1/50; it's like taking photos at 1/50 shutter speed.  If the scene is too bright, it will blow out.  If the scene is too dark, the footage will be too dark.  The way around this is to raise your ISO in low light situations, and use a variable ND filter on the lens when it's too bright.  Another way is to increase the shutter speed and/or close the aperture, although this will alter the look of your footage.

 

All-I means that each frame is captured as a single image and then compressed, like a stream of jpegs (kind of).  IPB compression is where a single keyframe is captured every so often, and only the differences from frame to frame are recorded.  In theory, All-I compression means that there is more data in the file, and it can be edited more easily, as each frame is differentiated.  However, it is up to you to determine whether you can see any difference between All-I and IPB compression.  All-I will result in larger files, so take that into consideration.  I shoot in IPB on the Panasonic GH4 and the quality is excellent, though I have no experience with the SL.

 

Log footage is intended to be colour graded.  It looks pale and washed out because it captures the most information in the highlights and shadows, a bit like a raw file vs. a processed jpeg.  Grading a log file is analogous to processing a DNG with the look you prefer, and turning it into a jpeg.  If you don't want to grade your footage, just shoot using a standard colour profile and the camera will take care of it.

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Archiver - thanks so much for such a great explanation. V much appreciated.

You're welcome, I hope it helps.

 

Just wanted to clarify something regarding log footage.  Even if you set the SL to record in Log, it is still a compressed file, which means that its ability to be processed (colour graded) is still limited.  This is essentially the same as the difference between a jpeg (compressed) and raw file (uncompressed).  There are dedicated cinema cameras that record in raw format, either in a format called Cinema DNG or a proprietary raw format, and these files are super malleable, just like still-camera raws.  However, these raw files are massive, as you can imagine.

 

Compressed log footage is maybe the equivalent of shooting jpegs in a very flat picture style.  You can process them, but you won't get the same level of control that you would from a raw file, if that makes sense.

 

But this is moot for you at this point.  I would look at the SL video settings options and adjust the contrast, saturation and sharpness to your taste.  I've had a look at the instruction manual, and it appears that the SL allows you to set the Sat/Con/Sharp for video.  If it were me, I would lower sharpness and contrast all the way, and lower saturation one or two clicks.  This usually gives a more natural and less harsh look to footage.  From the SL manual:

 

Contrast, saturation, sharpness

All options described on p. 196, but these are set separately for

video recording.

Setting the function

1. In the menu's IMAGE section, select Video Settings,

2. in the submenu, the desired item, and

3. in the respective submenus the desired settings.

 

Depending on what resolution you want, try 4K and 1080p and compare the footage on your computer, so you can see what you like better.

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  • 3 weeks later...

When the new Leica audio adapter for the SL becomes available in the States, I'll be buying.  I'm using a box (Beachtek), that has worked great with my 7D.  Left & right XLR ports and fully independent volume control of each channel.  Writes directly to the camera file. The Beachtek unit has an AGC on/off function.  

 

I noticed in the SL, that there is not an independent control of the audio (no levels, no balance), only 5 gain levels (including off).   To those in Europe that have the audio dongle, does attaching this dongle enable for precise left & right channel audio control?  If not, are the 5 gain levels adequate to achieve the audio levels' quality desired?

 

With the dongle attached, are you able to separate the L & R audio signal from the camera using a splitter coming out of the dongle, allowing the use of 2 external mic's?  IF yes, then having independent control of the audio channels  in the camera would pretty much be a necessity.

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