Its not just about pixels on the Phantom Flex 4K!
Yes, you get 4x the amount of resolution compared to a Phantom Flex 2K.
Yes, the Phantom Flex 4K is so much easier to use then previous Phantoms.
But, its the Dynamic Range is where the Phantom Flex 4K really stands out.
If you have ever worked with some of the older Phantoms, you will know that over exposure is deadly. When the whites blow out, they really blow out fast. Plus there can be a Magenta cast that is introduced with the previous cameras that the Phantom Flex 4K does not.
I remember working on a water job with the Phantom Flex 2K , everything was backlit, and we were filming a rowing crew for the Olympics. We captured amazing footage and close ups of the Crew, water splashing from the oars, looked amazing!
...yet we were overexposed by 1stop. This is where having a good DIT really helps by the way. We weren't in a position to review footage on the Phantom Flex 2K as we were on a pontoon, on a lake. We got the shot, and once we took the footage into Color Correction there was a Magenta cast in all the overexposed highlights, so this required even more work to remove the magenta cast.
All this would have been avoided if we had shot on a Phantom Flex 4K!
The overexposure latitude is remarkably better. According to Vision Research, the manufacturer of the Phantom Flex 4K.
“The dynamic range on the Phantom Flex 4K is higher, and the overall noise level of the Flex4K is significantly lower than the Flex (2K).”
“... The most obvious difference is the pixel resolution: The original Phantom Flex (aka Flex 2K), has a 2.5K sensor and the Flex4K has a full 4K sensor.”
The Native sensitivity of the Flex4K sensor is ISO 250T, and the exposure index can be extended to over 1000 (ISO equivalent) without significant loss of image quality.
The Flex (2K) has a base sensitivity of ISO 1000T, but its not recommended pushing the exposure index on that camera in order to maintain the optimum image quality.
The Phantom Flex 4K is super-35mm but with a full resolution of 4096 x 2304 and with 6.75 micron pixels.The Flex (2K) has a maximum resolution of 2560 x 1600 on a super 35mm CMOS sensor and a pixel size of 10 microns.
Another difference is that the Flex4K has a progressive scan shutter (with less than 1ms scan time), and the Flex (2K) has a global shutter.
(There is a newer Phantom Flex 4K with a Global Shutter, but you lose 2 stops Dynamic range, better suited for Scientific image capture.)
Regarding color processing, the Flex4K operates from the newer Phantom protocol, which lets you set the white balance in Kelvin as opposed to RGB gains like previous Phantom cameras. Powerful image processing controls like tone curves and color matrix are also possible with the Flex4K.
Also of interest are recording times and recording media of the Phantom Flex 4K.
The Flex (2K) uses the CineMag or CineMag II non-volatile magazines. These mount to the top of the camera.
The Phantom Flex 4k aka the Flex4K uses a new CineMag design, called the Phantom CineMag IV. The CineMag IV is available in 1TB and 2TB memory sizes. They mount in the side camera enclosure of the Flex4K, much like an Arri Alexa.
In both cases, Raw Cine files are transferred from RAM, or recorded directly to CineMag IV called Run Stop mode. (Run Stop mode has a 120fps limit at max resolution)
You can even record ProRes in the Phantom Flex 4K! The CineMag IV enables ProRes recording to save space and increase total record time.
The Flex (2K) has basic controls on the left side of the camera. But most of your controls are going to be from a computer attached via ethernet. Yuck.
The Phantom Flex 4K Flex4K has similar controls on the left side, BUT on the right side there is a new full menu system via LCD display that lets you control every setup and control parameter of the camera. It has the ease of use of an Alexa and can be operated without an ethernet tether.
Power & battery control
The Flex (2K) has two 24-volt power inputs. One can be used as the main AC power (220 watt power supply), and the other can be connected to a stand battery to use as a battery backup. OR, power the camera with a stand battery (like the Anton Bauer VCLX series)
The Flex4K is a little more flexible, it has one 24-volt power input, and three standard battery backs are available that support Hawk-Woods, V-Lock and AB-Gold mount batteries. Allowing both an AC power supply and an On Board battery with Hot Swap ability. Also making Handheld shots easy.
The Flex (2K) has two 1.5G HD-SDI outputs and one component video signal, and they all output an identical scaled 1080p or 720p output. The two outputs can work together to provide a 4:4:4 1080p signal.
The Flex4K has three main HDSDI outputs that can output at either 1.5G or 3G, and an additional SDI for viewfinder. Two of the outputs can be used together for a dual-link 4K signal. The camera can be set to continuously monitor the live feed where 2 of the outputs play back what was captured to camera RAM or the CineMag IV. The cameras outputs can also switch between Rec709 and Phantom LOG mode for monitoring purposes.
Massive amounts of Data
The Phantom Flex 4K can shoot massive amounts of data, so having an efficient method of downloading is crucial. Files in the CineMag IV can be downloaded through the Flex4K camera body or through the Phantom CineStation IV. Just about everyone uses the CineStation IV since The Phantom 4K only has a 1Gb Ethernet port, where the CineStation IV offers both 1Gb Ethernet and 10Gb Ethernet connections. With a fast destination like an SSD Raid you can download at about 300MB/sec on a Mac.
The files can be downloaded using windows-based Phantom PCC software or with Mac-based Glue Tools Séance software. One license of Séance comes with the Phantom Flex 4K purchase, also available from Glue Tools www.gluetools.com
There are a lot of video outputs and options on the Flex4K. How do the different video modes work?
The camera has three main 3G HD-SDI outputs at the back, one additional 3G HD-SDI output and one component video output at the front for viewfinders, and one HD-SDI. The camera supports:
- 4:2:2 1.5G 1080p/psf at 23.9, 24, 25, 29.9 Hz; 720p at 50, 59.9 Hz
- 4:2:2 3G 1080p 50 and 59.9 Hz
- 4:4:4 3G 1080p/psf at 23.9, 24, 25, 29.9 Hz; 720p at 50, 59.9 Hz
- Dual-link 4:4:4 3G 2160p 23.9, 24, 25 and 29.9 signals
The three main outputs are separated as 1x monitor (MON) output, and 2x recording (REC) outputs. The 2x REC outputs can be configured as individual 1080p outputs or used together to provide a dual-link 4K video output. All outputs must be on the same video system, and the 4K/2160p signal is determined by the settings of the other outputs / and vice versa.
The Component and HD-SDI viewfinder outputs (VF) at the front always work together, and provide the same image, with the same overlays, zoom modes, etc. The MON output can also mirror the VF output - this should be a common setup.
Versatile HD-SDI: The VF outputs and MON output can be set to always show a live signal, where the REC outputs are a clean feed that will switch between live and playback. This allows the DP & camera operator to always monitor the live action while the camera is playing back the last shot, or reviewing CineMag IV takes through the REC outputs.
Video scaling: When capturing at 4K resolution and outputting at 1080p (for example) the camera will always scale the video to 1080p.
Monitoring & Log outputs: The Flex4K video outputs can be switched between Rec709 and Phantom Log mode. All outputs are grouped together to display the same output. Various zoom ratios can be set from the camera body to help set focus. Production area rectangles and threshold mode are also available for the VF and MON outputs to help judge framing and exposure.
How long can you record with the Phantom Flex 4K?
The record time is completely dependent on the camera’s resolution, frame rate, and the size of memory that is being recorded to. At the camera’s maximum resolution and frame rate the camera will capture 5 seconds of video to 64GB. If recording directly to a 1TB CineMag at 96 FPS you can record for about 13 minutes. At 24 FPS you can record for about 56 minutes. But keep in mind most events that are captured at extreme Slow Motion rates typically take place in a small period of time, like an object falling into water is just a few seconds. Also play back of long recording times become too long for most
Here is a good Record Time Calculator. by Vision Research.