Pluraleyes with multiple cameras and separate sound

Recently I have been playing around with using Pluraleyes to synchronise multiple cameras, all containing "scratch" audio, together with sound recorded on a separate solid state audio device. Once again, Pluraleyes worked flawlessly (once I developed a additional stage first) and the fact that it also automatically makes a multi-clip for Final Cut, makes it even better. I will shortly be testing out the new multi-cam and synchronise feature in Final Cut X which might make this method redundant, but here is my workflow for synchronising multiple cameras and separate sound for multiclip editing:

Firstly, transcode footage to both ProRes and ProRes PROXY (this is done as sometimes, depending upon the number of clips, and the power of your machine, Final Cut will struggle with the playback).

Secondly, use Pluraleyes to sync the separate sound to one of the camera angles.

Thirdly, export this as a new Quicktime file (you can use the reference movie option to save disc space).

Now, reimport this file back into Final Cut and use Pluraleyes to sync this file to the remaining camera angles.

Pluraleyes will make a multiclip with all cameras now synchronised.

Once edited, one can use the RECONNECT MEDIA option to relink the edit back to the original ProRes files.

Update

It's been a while since my last post, but just wanted to add a quick update to the Blog. Firstly, I have recently purchased a DSLR base plate with standard rods from a supplier in Hong Kong via eBay. Usually these things retail for around £150 minimum, but I paid about £58 so very pleased about that. The beauty of these things is that they allow for better positioning of my DFocus follow focus and also, at a later date, it is easy to adapt it into a full shoulder rig too.

Here is a quick picture of it:


As can be seen from the picture, as I have a battery grip on the 550D, the rods become too low to allow the gears on the FF to match up with the lens gear. Therefore, I sourced an additional pair of 6" rods and a riser from eBay to effectively "lift" the FF up closer to the lens. One can obtain something called the "DRISER" from Jag35.com to do the same thing, but this actually works out more expensive than buying two rods and an adaptor!

I also fitted the DSLR base plate with a Manfrotto quick release plate so that it can be quickly detached from the tripod.

Also looking at purchasing either a Canon 28mm f1.8 USM lens or Sigma 30mm f1.4 lens but can't decide which one. The Canon is probably slightly better than the Sigma, but the Sigma is a little bit "faster" with its 1.4 aperture.

Very recently also bought a new microphone too. I didn't want a shotgun as I can borrow these quite easily, but did want a cheap hypercardioid mic for indoor work. The choices are either the AKG CK93 capsule on the SE300 body (about £300), or the AT 4053b (about £450 ish), the Oktava MK-012 or going much more expensive, something from Schoeps. I didn't want to spend a great deal, and was lucky enough to find some end of the line Studio Electronics SE2A true condenser mics with three capsules (OMNI, CARDIOID and HYPER-CARDIOID) for only £75. The mic is lightweight and seems to perform well.

Timelapse video

Been playing again with creating timelapse video sequences and now I understand the process much better.

Firstly, unless you really need the extra resolution (i.e. perhaps you plan to zoom in on a section of video for example), then the camera can be set to its lowest JPEG image setting. In the case of my 550D this happened to be 2592 x 1728 which is obviously much higher than is needed for standard 1080P HD video.

Secondly, as most DSLR cameras take their pictures with an aspect ratio of 3:2, we need to ensure that when exporting the image sequence to 1920 x 1080, that the aspect ratio is preserved, otherwise horizontal stretching will occur.

Any way, the way I carried out my timelapse was to record a series of images every 5 seconds (using Magic Lantern's built in intervalometer) and to simply then take these into Quicktime Player 7 using its "OPEN IMAGE SEQUENCE" option.

Upon doing this, a window will appear asking what frame rate to use - I simply chose the standard PAL of 25fps.

The sequence can then be exported and I chose to use Apple ProRes LT (in case I wanted to take the finished video in a FCP project) with a resolution of 1920 x 1080. IMPORTANT: you need to make sure that PRESERVE ASPECT RATIO using CROP is selected to ensure that the resultant video file is not stretched.

Job done!

Canon 5D MKIII or 6D?

Been thinking lately about whether to jump to full frame and get the 5D MKII. Currently (Sept '11), you can snap (excuse the pun) a 5D MKII and 24 to 105 f/4 IS L lens for around £2100. This fairly large discount must be due to the imminent arrive of the 5D MKIII or its equivalent.

I watched a few comparison videos last night looking at the features of the 5D MKII and the 7D and from these, what I have learnt is that I'd like a full frame version of the 7D and not really the 5D MKII which has a few outdated features.

I therefore came across a few rumours of a "6D", which will be a lower priced full frame DSLR with perhaps the features of the existing 7D :)

Hopefully this will happen soon......

DSLR Cinema

I've recently been told about a new book called DSLR Cinema by Kurt Lancaster. Looks good and have ordered a copy....

Field of view tool

This is an excellent tool for showing the difference between different sensor sizes and how it affects the field of view. Wish there was one to show DoF too.

http://www.abelcine.com/fov/

Glidetrack Shooter SD

Just purchased a Glidetrack Shooter SD from Alistair @ www.glidetrack.com. I cannot recommend this product highly enough - it is simply an awesome piece of kit, especially when linked with the Manfrotto 577QR quick release place and Manfrotto 701HDV head.

Here are few videos I have shot with it recently:

http://www.vimeo.com/17981477

http://www.vimeo.com/17979791

http://www.vimeo.com/17953967

1/30s Shutter?

Due to the 180 degree shutter used in film cameras, the optimum shutter speed on a digital SLR should usually be around 1/2n where n = frame rate. For PAL 25fps therefore, the shutter should be 1/50s. If you shoot with a higher shutter than this, you can get very "staccato" looking images, especially during fast motion shots. However, what about shooting at the camera's minimum of 1/30s? The image might become too soft and there might be too much motion blur, however it's something I am going to try soon. The benefit of this is that for low light shooting, you can get away with a lower ISO or smaller aperture.....

Posted a demonstration video showing different shutter speeds at my Vimeo pages: www.vimeo.com/digitalvideoslr

DSLR CAMFRAME

Just bought a DSLR Camframe from B-Hague in Nottingham as shown here (without the camera which was taking the picture!). It provides side and top handles together with two additional hot shoe mounts (which I have used to mount my 126 LED light to one side, and HDMI field monitor / Zoom H4N to the other side).

Canon XLH1s vs. Canon 550D

Decided that in a few weeks time I am going to make a demonstration video comparing the differences / similarities of the Canon 550D SLR and the Canon XLH1s camcorder. I want to compare the DoF available with the same aperture on both. The Canon XLH1s, like many camcorders is around a x7 crop factor so I would have thought that with say an f1.8 aperture, the DoF is still going to be extremely deep. The plan is to film a tape measure from an angle so that the DoF can be measured and compared. The camcorder lens is a 5.5mm to 108mm "L" lens (equivalent to approx. 38mm to 778mm in 35mm format) and has a maximum f number of 1.6. Should be an interesting comparison.

Light tests

Have just taken delivery of 126 LED light. Will post a comparison video of it very soon when I get chance to make one!

Jamie's 30 Minute Meals

Just been watching a behind the scenes video of Jamie Oliver's new Channel 4 series and noticed that they were using a DSLR for some of the shots. Looked like the 70 to 200l f2.8 lens was being used in one of the shots. They also appear to be using RED ONE cameras too.

http://www.channel4.com/food/on-tv/jamie-oliver/jamie-s-30-minute-meals/index.html

LIGHT

Been looking at the Litepanels range of portable LED lights to sit on top of the camera. Their Micro Pro looks excellent but it retails for around £300!

I therefore visited eBay and after a bit of hunting around and review checking on YouTube, I have opted for the "CN-126" 126 LED light panel, which apart from being made from plastic, looks more or less the same as the Litepanels one. The best thing is that it retails for £37.50 and will take rechargeable camcorder batteries.

It also comes with a diffuser filter too and is totally dimmable.

Great Sound Design Website

I always like to show my students sound design / sound for picture "making of" documentaries as I think that they inspire students to start wanting to play with sound and go out and about acquiring sounds which they can later work with.

A student told me about this website yesterday and it simply is fantastic with lots and lots and lots of documentaries regarding sound design for films:

www.soundworkscollection.com

Tokina 11 to 16 f2.8

I think my next lens purchase will be the super wide Tokina 11 to 16 f2.8 lens. It doesn't seem to get a bad review anywhere and it's specially made for cropped sensors. On the 550D, the focal length will be around 18 to 26 which is still nice and wide.

Why a Crop Factor of x1.6 on APS-C sensors?

Just been reading around: (I think this is correct!)

http://en.wikipedia.org/wiki/Crop_factor [accessed 02/10/2010]

http://en.wikipedia.org/wiki/Charge-coupled_device [accessed 02/10/2010]

http://www.december.com/john/photography/cropfactor.html [accessed 02/10/2010]

to try and ascertain a good formula for calculating the crop factor between a full frame sensor and an APS-C sensor (used by 550D / 7D etc.).

The dimensions of a FULL FRAME sensor is 36mm x 24mm with a aspect of 3:2. Dimensions of an APS-C sensor is 22.7mm x 15.1mm, again with a 3:2 aspect.

Square root of (36^2 + 24^2) DIVIDED BY the square root of (22.3^2 + 14.9^2) = 1.6 approx.

This explains why the DoF on camcorders with such a small image sensor (6mm diagonal, 4.8mm x 3.6mm in the case of a 1/3" CCD), are so deep.

The crop factor of this 1/3" CCD sensor would be around x 7. Now, the ratio between each successive f stop is ROOT 2 or 1.414. Comparing a FULL FRAME f stop to an APS-C 1.6 crop shows that the difference in effective f number is around 1.13 fstops (i.e. 1.414 x 1.6). By this what I mean is that f4 on a FULL FRAME camera equates to f2.5 on a 1.6 crop. Now f2.8 would be ONE FSTOP wider, (i.e. 4 / 1.414) so f2.5 is slightly wide than this. Therefore, returning back to the previous example of a 1/3" CCD sensor with a crop factor of x7, how many effective f stops wider would the lens need to be to give the same DoF? Well, 7 / 1.414 = 4.95. Therefore, approx. 5 fstops wider! A 50mm lens with an f8 aperture on a FULL FRAME camera would therefore require 7mm lens with an f1.4 aperture to give approx. same DoF. If we took the same 50mm lens with an aperture of f2.8, we would need an aperture of f0.5???

The 1/3" example above doesn't have the same aspect ratio however, so the calculations will probably differ slightly :)

[Addition]: What about the difference between a x1.6 cropped sensor and 1/3" CCD? Well, as mentioned above, the dimensions of an APS-C sensor is 22.3mm x 14.9mm (diagonal of 26.7mm) and the dimensions of a 1/3" sensor is 4.8mm x 3.6mm with a diagonal of 6mm. Therefore, the crop factor between the APS-C and 1/3" is 26.8 / 6 = 4.55.

It would therefore seem that the effective change in f stops between these two sensors is 4.55 / 1.414 = 3.22 f stops. What this means is that f/8 on an APS-C camera would be the equivalent of a little over f2.8 on the 1/3". Also, to obtain the same field of view on the 1/3" camera, one would need to use a lens 4.55 times smaller (50mm lens, 35mm equivalent = 80mm on APS-C camera and 364mm on 1/3" sensor). So, to give same field of view, I would need to set the lens on the 1/3" camera to 80 / 4.55 = 18mm approx.

A test is going to be carried out to establish whether this is the case, by comparing both the field of view and Depth of Field between a 1/3" video camera and a Canon 550d (APS-C sensor). Watch this space!..... will place a demonstration video on Vimeo.

Here is an interesting article which shows some example shots taken with two different sensor sizes and it sort of agrees with what is being said here:

http://www.janrik.net/DOFpostings/PM1/Depth_of_Field_Versus_Sensor_Size.html [ accessed 14/11/2010].

The crop factor between the two cameras is x3.07. To obtain the same DoF on both sensors, one needed to be set to f/4 and the other f/13. This is very interesting as this represents a little over 3 f stops difference (i.e. f/5.6, f/8, f/11 and a bit more to f/13). The focal length must also have been set to 3.07 times shorter too, although it doesn't stage this in the article. My theory that that the change in f number is equal to the crop factor / divided by 1.414 doesn't therefore ring true here, so it will be interesting to see what my test demonstrates.

[EDIT - 10/01/2010] - JUST FOUND THIS AWESOME FIELD OF VIEW CALCULATOR / DEMONSTRATION TOOL:

http://www.abelcine.com/fov/

DAM - Digital Asset Management

There's not really a right or wrong answer to "looking after" all of the assets which make up a project, but the need for a decent asset management strategy, especially when using double system sound is very important. Students often run into problems when moving from one edit suite / studio to another, and often leave some of their files behind. I have therefore created a basic flow chart which discusses a solution (not THE solution) to help make asset management easier.

This video http://www.vimeo.com/14840608 which I thought was excellent, runs through some really useful methods; my flow chart is attached here too, with a couple of extra stages added if necessary, such as setting up the scratch disc and exporting to ProTools for further sound editing .... (please click on the picture to open it and so that you can read it properly).

The flow chart (and video) makes use of Final Cut's MERGE CLIP feature when using double system sound and this has been discussed and demonstrated on this Blog previously. Equally, PLURALEYES could be used for the automatic sync'ing of clips if a clapperboard of some kind of sync point was not used......

First Electronic Viewfinder for DSLR

Redrock micro have jsut announced the world's first HDMI electronic viewfinder for HDSLR cameras:

http://www.dslrnewsshooter.com/2010/09/26/redrock-micro-launches-the-microevf-for-hddslr/

Monopod

Went out with the camera this morning to a local nature reserve to have a further play with my new 70 to 200L f4 lens. However, this time I also took a monopod and what can I say, these things are great and help take the weight incredibly well. When normally holding the camera with the lens at its maximum focal length, it's so tiresome to hold it steady; not with the monopod!

Great!

Audio drifit issues

Found a very interesting article here discussing a "glitch" in Final Cut Pro which sometimes can cause separate audio to start drifting from the picture:

http://brucesharpe.blogspot.com/2009/06/dslr-dual-system-audio-999-solution.html

I intend to make a demonstration video discussing this shortly.....