It’s taken me a while to finish this review as I’ve been pretty busy. While preparing it I posted various frame grabs that I pulled from the Samurai and the Gemini on a couple of blogs and forums and these have created a bit of a stir that was never intended.
Anyway, what about the Samurai? Well to be honest I was impressed before I had even turned it on. When you buy a Samurai, not only do you get a neat little video recorder, but you also get a flight case full of everything you need to use the recorder (with the exception of a hard drive or SSD). The flight case contains the Samurai itself, a couple of adapter cables to go from the mini BNC’s to full size BNC sockets. A couple of batteries, a neat dual channel charger, a pair of drive caddies and a docking station for off loading your material. Everything is well made.
One of best bits about the Samurai is that it is extremely simple to use. A push button on the side turns it on and your quickly greeted with the home screen. From this one screen you can record clips, enter playback mode, go in to monitor mode, format a drive, turn on timecode triggering and choose whether your progressive files get tagged as interlace or progressive (more about that in a bit).
For my tests I used a 250Gb 2.5″ hard drive that I had kicking around. I’m not a fan of using spinning discs to record on, but in terms of cost per GB they are very affordable. The discs spin at between 5,400 and 7,200 rpm and this means there are some quite high gyroscopic forces in play. Twist the unit too fast or drop it and you may damage the disc leading to the loss of valuable material. The Samurai though, can also use SSD’s (Solid State Drives) which are very fast, cost effective memory devices with no moving parts. If your going to be bumping your Samurai around an SSD is the way to go, but if you need lots of cost effective storage a hard drive may work better for you, provided your sensible with it. One recommendation of my own is not to be tempted to use one big 750GB hard drive, but instead to use several 128GB or 250GB drives. This way if a drive is lost or does fail you don’t loose quite so much. While you should, as I did, be able to use pretty much any drive, there are a few that Atomos do not recommend. Atomos regularly test new drives as they become available and they provide a list of recommended hard drives and SSD’s. It’s almost certainly best if you choose your drives from the list, which can be found here.
There are very few menu settings on the Samurai and this makes it simple to use and fast to set up. If your using a camera with “record run” timecode the Samurai can be set to watch for rolling timecode and as soon as it does go in to record. I found a 2 or 3 frame delay between the camera going into record and the Samurai triggering, which is noting at all and in most cases you’d probably never realise there was this minute delay. Of course you can also press the big red record button on the touch screen LCD or if you have a camera with LANC you can plug a LANC controller into the Samurai and then plug the Samurai into the camera. The remote would then trigger both units together.
One of the buttons on the home screen turns on and off PsF recording. PsF is the method used to send 1920×1080 progressive footage via HDSDi. PsF is used by just about every 1080P camera. It’s clever because it allows you to plug a progressive camera into an interlace monitor, and everything still works just fine. It does this by taking the progressive image and splitting it into 2 fields before passing it down the cable. So to the receiving device (monitor, tv, recorder etc) it looks like an interlace signal, but as there is no temporal (time) difference between the two fields, when shown on an interlace monitor what you end up with is a progressive image. The issue with this is that when you feed something like the Samurai with a PsF signal,it can’t tell whether it’s getting a progressive image split into fields or a real interlace image with two fields. This is where the Samurai’s PsF button is useful as it allows you to tell the Samurai whether the signal is progressive or interlace so that the recorded clips are correctly flagged. A word of CAUTION about this. If you are at all unsure, it is safer to not flag the clips as PsF. Why? well once a clip is flagged as PsF your edit software will always treat the odd and even lines within the frame as occurring at the same moment in time, so any effects or renders will also be progressive and this may result in motion artefacts. If you have a PsF clip flagged as interlace this problem does not occur as generally if you render from interlace to progressive the fields get combined anyway.
POWER AND BUILD:
Moving on… On the back of the Samurai are locations for 2 Sony NP series batteries. These are really common batteries that can be purchased very cheaply. Atomos will also provide you with a free D-tap adapter if you wish to take power from a 12v battery. To get the adapter all you need to do is to register your Samurai on the Atomos web site. You can also by additional adapters and a power supply from you Atomos dealer. The batteries can be hot swapped so in theory you could shoot forever, or at least until you drive is full.
The build quality is very good. The bulk of the unit is machined from aluminium, so it should take the general bumps an knocks of professional use. There is a 1/4″ threaded mount on the top and bottom of the chassis for mounting. HDSDi Input and output is via mini BNC connectors and Atomos provide you with a couple of adapter cables that go from a mini BNC plug to a standard BNC socket. While this works OK, on the review sample the connectors were straight and as a result these rather thin connectors stick out quite a long way. I don’t like this, they look a bit vulnerable to me. Atomos tell me that are looking into right angle connectors and this would be a big improvement in my opinion. The touch screen also acts as a monitor so you can check that you have not got the camera overlays turned on by mistake. Some external recorders don’t have a monitor and I’ve heard horror stories of entire shoots being ruined because the operator didn’t realise that the camera data was getting recorded burnt into the video clips. It’s not the brightest of screens and perhaps lacks a little contrast, I think some of this is due to the membrane used for the touch screen, but it’s very useable. I could probably benefit from some kind of hood in bright conditions.
BENEFITS AND IMAGE QUALITY:
So why do you need an external recorder, most cameras are capable of producing a good image without an external recorder aren’t they? Well in general, yes, most cameras will produce an acceptable, first generation image. But when you start making multiple copies or doing extensive post production work on the internal recordings, very often they simply aren’t up to the task. Take a look at the frame grabs presented here (click on them to view full size), one recorded internally on the F3 at 35Mb/s and the other on the Samurai using ProRes HQ at approx 185Mb/s.
When you look at the unprocessed, 1st generation frames, it is perhaps hard to see a difference, but when you do just a little bit of post production grading then the difference becomes much more noticeable. The crop is of the top right part of the frame. The tree branches were blowing in the wind and this motion makes the codec have to work quite hard. When there is only 35Mb/s of data to play with the codec really struggles, while the extra data available to the ProRes codec of the Samurai means that the codec isn’t struggling at all. The other thing in this example is that the F3’s internal recordings (like most AVCHD or Mpeg2 cameras) use only 8 bits of data and the colour is sampled 4:2:0. The Samurai is 10 bit, 4:2:2.
MORE BITS ARE BETTER:
With an 8 bit recording you only have 235 brightness levels. That’s fine if you don’t manipulate the image in any way, but if you modify the image contrast or brightness you will create gaps and jumps between those steps and this will appear as banding in your pictures. 10 bit recordings have 940 brightness levels, so any steps will be much, much smaller so banding after adjusting brightness and contrast is significantly reduced and is not normally visible.
When you compare 4:2:0 against 4:2:2, the later has twice as much colour detail than the former. Now I have to confess that I often to struggle to actually see this difference in progressive material, but if you shoot interlace you can see a difference. In either case, having more colour detail will once again improve the flexibility of your material in post production and can give a small improvement in the appearance of chroma noise.
NOISE AND MACRO BLOCKING:
Talking of noise…. if you choose to look closely at the frame grabs I have provided then you may think that the recordings from the F3 have less noise than the Samurai. Well, they do and they don’t. You won’t see as much fine grain noise in the 35Mb/s frame grabs as the Samurai frame grabs because the F3’s internal codec has to discard a lot of picture information to fit it into 35Mb/s. One of the things that gets discarded is noise, but as well as noise there is also a loss of some subtle fine textures. So be careful when you look at the images, the F3 material may look cleaner, but it’s also lacking the fine detail and texture that has been captured by the Samurai. Check out the video below. First you see the full frame clips from the F3 and Samurai, ungraded and then graded. Finally you’ll see crops from the clips. Check out the ugly, blocky artefacts from the F3’s internal recordings on the first clip, then the breakup of the leaves in the second clip and finally the strange wobble of the hedge and bricks in the last shot. These are all typical motion artefacts from the long GoP Mpeg 2 used by the F3 internally.
Please watch the clip full frame 1920×1080. Please also consider that youtube adds a lot of artefacts of it’s own, but the side by side clips will be affected equally. Try pausing the clip during the side by side branches clip.
These may seem trivial in a highly compressed web clip, but let me assure you they are plainly visible on my 42″ TV. When I did compare the Samurai to the Convergent Design Gemini which is a fully uncompressed recorder there was not a lot between them. The Gemini does produce a slightly better image as it has the capability of recording a pristine, mirror image of what comes out of the camera, there is no compression, no loss, no artefacts and if quality is your absolute priority this should be the type of recorder to consider. But the Gemini produces some very, very big files that will need to be backed up and stored. For example an hour of material from the Gemini requires 750GBs worth of the very fastest SSD drives. A 750GB hard drive in the Samurai costs less than 1/10th of the price and will record over 16 hours of material. Not only that but you can backup 16 hours of Samurai material in around the same time as it would take to backup 1.5 hours of Gemini material. In terms of image quality I would say that the Samurai is more than adequate for most types of production, so you do have to ask yourself whether the small quality improvement you can get from the Gemini justifies the more expensive, more complex and slower workflow? Me personally, I’m seriously considering the Samurai as my recorder of choice for all my day to day production work. I’ve looked at the Pix-240 and it’s just too big and bulky, the Ki-Pro mini doesn’t have a monitor and the NanoFlash is only 8 bit. The Samurai ticks all the right boxes. However, if I have a big screen, high end production where the more complex Gemini workflow is not an issue, then for those productions I would use the Gemini. It’s horses for courses, the right tool for the job.
For the money the Samurai is all but impossible to beat. Lets face it, the price is very good. Sometimes a price can be too low, I often associate cheap prices with sub-standard products. While the price is low, the Samurai however is not sub-standard. It’s well put together, very capable and has good recording media flexibility with the option to choose codecs (ProRes or DNxHD) and media types (SSD or HDD). With the PMW-F3 it can be used with standard gammas or 422 S-Log. It brings a significant improvement to the quality of the images you can record and makes the workflow even easier than when your using SxS (no need to re-wrap from MP4 to .mov with FCP). I think its great as an all-round every day recorder. 9/10
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