OLED—Organic LED—is said to be the display technology of the future… and it’s here today. The PVM-740 is the smallest of Sony’s trio of professional-series OLED displays, and Sony lent me one for a while when I was testing the NEX-FS100.
It’s nice. I mean, it’s really nice. Perfect? Well, not quite, but darned close; let’s just say I’ve reset my expectations when it comes to reference displays.
Art Adams has a good writeup on the technology, so have a snuffle through that if you need background info. All I’ll add to that discussion is Sony’s spider plot comparing display technologies, from HPA 2011:
Relative performance of different display technologies, according to Sony.
Sony’s first PVM-series OLED display is the US$2725 (list price) PVM-740, a 7.4″, 16×9 display with a 960×540 resolution. It now has two big brothers, the $4,100, 17″ PVM1741 and the $6,100, 25″ PVM-2541; and four rich uncles: 17″ and 25″ BVM-series OLED displays ranging from $11,500 to $26,000. All the 17″ and 24″ displays use 1920×1080 panels. These monitors differ in bells ‘n’ whistles, but all share the same basic display technology and the image quality resulting from it.
Design
The PVM-740 is a robust, portable flat-panel monitor. Its metal housing is about 9″ wide, 6.75″ tall, and 3.25″ deep; with its removable foot attached, the height goes to 7.25″ and the depth to about 6.5″. The monitor alone weighs 4 lb 6 oz; add on its dockable AC adapter and it’s 5 lb 12 oz.
The monitor is mounted on a metal-and-plastic foot assembly which holds the monitor upright. You can tilt it up about 15 degrees with a flip-down prop.
The PWM-740 showing a 1080/60p signal via HDMI, with WFM displayed and button-label backlighting turned on.
The front panel has a tally lamp at the top and the screen itself recessed behind a protective plastic cover. There’s a 3.5mm stereo headphone jack, a small speaker, three input-selection buttons, seven programmable buttons, a multipurpose jog dial, menu-control buttons, and a power switch. The button legends can be backlit, and the input-control and function buttons all have red LEDs to indicate their selection.
Rear of the PVM-740, without AC adapter.
The monitor has SDI and analog composite loop-through inputs, an HDMI input without loop-through, and stereo minijacks for separate audio input and output. Embedded audio is detected for both SDI and HDMI inputs, and two selected channels can be monitored (and output) as analog. There are also parallel and ethernet remote-control ports.
A small, quiet fan keeps the electronics cool, but you can shut it off when necessary. Power is provided through a 4-pin 12v DC connector, or through V-mount batteries, or the supplied V-mount AC adapter, which accepts voltages from 100-240V. The monitor consumes about 27 watts.
Right side of the PVM-740, with its AC supply nearby.
Left side of the PVM-740, propped up, AC supply attached.
Both sides and top of the monitor are finned for heat dissipation, and have mounting holes for rack-panel fittings.
Underside of the PVM-740.
The monitor has both 1/4″ and 3/8″ sockets on its base, so you can stick it on an articulating arm as an on-camera monitor, or mount it on a tripod for freestanding field use.
Features
Inputs and Formats
The PVM-740 is a highly flexible multi-format monitor, handling NTSC and PAL composite signals as well as SDI and HDMI at 480/60p; 576/50p; 720 at 50p and 60p; and 1080 at 24p, 25p, 24PsF, 25PsF, 30p, 50i, 50p, and 60p. NTSC-area signals are supported at both fractional (1000/1001, e.g., 59.94Hz) and integer (e.g. 60.00Hz) rates.
The PVM-740 accepts embedded audio on both HDMI and SDI signals. When SDI is used, you can monitor (mono through the speaker, stereo through the headphone output and line jack on the back) any consecutive pair of the 16 signals available over SDI (1+2, 3+4, etc.).
When you switch inputs, the screen blanks for a couple of seconds while the display locks onto the new signal.
Color Rendering
The 740’s native white point can be set to D65, D93, or a user-tweakable setting. You can copy either D65 or D93 into the user settings and then adjust RGB signal gain and bias (DC level) as you see fit.
You can also choose from four color space settings: native, EBU, SMPTE-C, or ITU-709:
PVM-704 in native color mode.
PVM-704 in SMPTE-C color mode.
PVM-704 in EBU color mode.
PVM-704 in ITU-709 color mode.
The monitor can accept RGB signals over HDMI, and you can choose to display the signal based on either full-range (0-255) or video-range (16-235) signal levels.
Scanning
You can choose from a 5% overscan, a full-frame (“normal”) scan, and a pixel-for-pixel (“native”) scan.
PVM-704 in “over” 5% overscan mode.
PVM-704 in “normal” full-frame mode.
PVM-704 in “native” 1:1 mode.
The native scan shows you exactly what you’ve got in your source image, though it’s always centered; you can’t choose what part of the image to zoom in on.
You can choose three interlaced-to-progressive conversion methods: INTER-FIELD, in which each displayed frame is created from a field’s native lines and interpolated data for the missing field’s lines; FIELD MERGE, to simply display both fields as-is, at the expense of seeing interlacing artifacts; and LINE DOUBLER, which simply doubles the lines in each field to fill in the missing field’s data. Line doubler has the least processing delay, but shows more line flicker or twitter.
The manual notes, “[A]s the line flicker is displayed in this mode, it is available for checking the line flicker of the telop work and so on.” While this makes perfect sense for the Japanese, it may leave gaijin in the dark: “telop”, from “television opaque projector”, is a catch-all term in Japan for TV graphics, whether produced with art cards in a traditional “telopper” or electronically generated in the modern manner.
You can also flip the image horizontally and/or vertically (useful in 3D mirror-rig monitoring) and add H/V delay (cross pulse display).
Display Functions
The monitor includes a small waveform monitor display, positionable in any of the four corners of the screen. The WFM includes audio level meters (ALM) for the two audio channels currently being monitored.
PVM-740 showing WFM/ALM overlays.
You can also toggle to an 8-channel ALM instead of the WFM/ALM display. This makes sense for SDI inputs with up to 16 channels; either channels 1-8 or 9-16 will appear, depending on which set contains the two channels you’ve selected for monitoring.
Turning the WFM/ALM display on or off blanks the screen for a couple of seconds, just as if you had switched inputs. It’s very distressing the first few times it happens, especially if you’re used to other field monitors (like the Panasonic 8.4″ and 17″ LCDs I normally use) that show or hide the superimposed WFM with no image disruption at all. Even after a couple of weeks, it still startled me to have the picture vanish when I pushed the function button assigned to WFM; I always thought I’d changed inputs or done something else drastically wrong.
The 740 offers markers as well: a center cross, and a variety of aspect-ratio crop marks (from 4×3 through 2.35:1 in 16×9 display mode, but only a 16×9 marker in 4×3 display mode). You can select bright or dark markers, and also choose to dim areas outside the aspect ratio selection.
Markers and WFM/ALM display are mutually exclusive.
In addition to the usual APERTURE (edge enhancement, or sharpness) control, the 740 offers a CAMERA FOCUS setting. It applies a fixed, high amount of edge enhancement to the picture. It’s a nod to the needs of 1st ACs, but it’s not nearly as useful as the fully-adjustable, colored-edge focus-assist functions on, say, the Panasonic BT-LH80 or TVLogic LVM-074W.
Next: Performance and Conclusions…
Performance
It’s difficult to pictorially convey the fundamentals of this monitor, because in all likelihood the display you’re reading this article on significantly underperforms the PVM-740 in most important aspects. And if I describe it in words, I sound like a craven marketeer or fanboy…
Color
Color is rich, saturated, and (as far as I can tell) as true to life as any display I’ve used. The PVM-740’s wide gamut exceeds that of the EBU, 709, and SMPTE-C color spaces; to my eye it’s as rich as the native gamut on the HP Dreamcolor and Sony XBR8 LCDs, both of which use RGB backlights. Look at the “color space off” image on page 1 along with the “709” image to get an idea of the difference between the native gamut and the comparatively impoverished color space we normally work in.
As Art describes in his article, the deep black the screen is capable of helps preserve saturation as brightness levels decrease, leading to an even richer chromatic experience than you would otherwise expect.
What did Alex say in “A Clockwork Orange“? “It’s funny how the colors of the real world only seem really real when you viddy them on the screen.” That’s what the OLED display does for you. Put the monitor in “color space off” to wow the client. Just don’t forget to switch it back to EBU, SMPTE-C, or 709 when you’re done, otherwise the intensity of the displayed color may cause you to seriously desaturate your camera’s settings.
Tonal Scale
One of the first things I did with the PVM-740 was set it up in Studio B with a capped camera feeding it, close the doors, and shut off the lights. “Aha”, I said, “I see the ‘black’ screen even in the dark!”
Then I turned on the WFM, and noticed that the camera’s black level was a bit high. I reset the camera’s master black to zero while watching the WFM, and turned the lights in the studio off again. All I was able to see then was the two lit LEDs on the base of the monitor. And a good thing, too; otherwise I’d have been totally blind. When Sony says that “black” on the OLED display means “no light”, they aren’t kidding.
The only way I can really show this off is with the following demo: I turned off the lights in the room where I shot my pix, so I only had a bit of stray light filtering in from the room adjacent, and cranked up the exposure on the still cam to bring up shadow detail:
PVM-740 on, showing a black frame; button label backlighting turned off. 1/5 sec, f/2.8, ISO 3200.
PVM-740 turned off. 1/5 sec, f/2.8, ISO 3200.
Those vertical white smudges on the screen are the reflection of my tripod’s legs.
Brightness, Contrast, and Usability
As you crank up the brightness, the screen gets brighter… and that’s it. There’s no lift in the black levels, as with raising backlight brightness on an LCD; nor is there any blooming, defocusing, or halation as you’d get on a CRT.
You can put a 100% pulse pattern into the monitor, and crank brightness up all the way. Any white pixel will be the whitest white it can possibly be. The black pixel next to it will be utterly black.
Brightness overall is more than adequate for any indoor use. Outdoors, with midafternoon sun glaring full on the faceplate, I found myself wanting a hood: even an OLED monitor is no match for the giant nuclear furnace that is our sun.
Resolution
The PVM-740 is a half-res HD display: it’s 960×540, while its bigger brothers are full-res 1920×1080. Put it in “native” 1:1 mode, and those pixels are as sharp and distinct as on any other display.
Viewing Angle and Consistency
Sony quotes the viewing angle to be up to 85 degrees off-axis while maintaining a 10:1 contrast ratio—but that’s not a very useful metric.
Practically speaking, the image is perfectly even and consistent within about 30 degrees of head-on viewing. Once you get about 30 to 45 degrees off-axis, you’ll notice a dropoff in brightness, and a slight cooling of the image, until, by the time you’re at 70-80 degrees or so, there’s a noticeable blue tint (at least when you’re testing with a white field, as I was). This variation in level and color is the same whether you are left, right, above, or below the monitor’s ideal viewing axis.
PVM-740 off-axis response: constant exposure settings, white field displayed; color-balanced off the screen viewing it head-on.
Fortunately this dimming and blueing is consistently applied across all the hues and tones of the image; there’s no tonal inversion, solarization, or differential hue shift the way there often is with LCDs. The chap off to your left may see a somewhat darker and cooler image than you do, but at least his blacks won’t have turned purple and become brighter than his mid-grays.
In short, if you treat this display like one of the higher-quality IPS LCDs as far as off-axis viewing is concerned, you’ll be fine. It’s not bad as flat panels go, though the CRT is still the winner in this competition.
(It’s worth noting that this may not be a limitation of the fundamental OLED technology. At the Snader ETECS trade show in February, a chap in the TV Logic booth said that the 15″ LEM-150W OLED monitor doesn’t suffer from the same dimming-and-cooling off-axis response. However, I wan’t able to confirm that with my own eyes. The LEM-150W costs over $6,000, too!)
Motion Rendering and Flicker
[Note: I did my testing in the middle of January. In mid-February, Sony started offering a firmware update that adds an additional refresh mode; details following the discussion.]
While shooting the photos for this article, I noticed a random band of brightness appearing onscreen, so I decided to measure the “on” time for 740’s screen by shooting stills of it at varying shutter speeds, and seeing if I could learn anything by comparing them. The “on” time, at least with a 1080/60p signal fed from an NEX-FS100, seems to be about 6.9 msec: 41% of the 1/60 second frame, based on shooting a 1080/60p image with a DSLR at 1/8000 sec, and comparing the illuminated height of the screen with a shot of the same screen fully-illuminated in a 1/60 sec photo. As Sony described at HPA 2011, this “on” time achieves a balance between sharp motion rendition and too-noticeable flicker.
By comparison, a common CRT’s “on” time is less than .28 msec (1.7% of a 1/60 sec field time, measured as four lit scanlines out of 240 in a 1/60 sec interlaced field on a PVM-1354Q, captured in a 1/8000 sec photo. Consider than 1/8000 sec is 0.125 msec, about the time it takes for two scanlines to be traced on the CRT’s faceplate, so the measurement of a 1/8000 sec photo will overestimate the time a single spot on the screen is lit). The CRT’s “on” time is at least 25 times shorter than the OLED’s; practically speaking, the CRT’s phosphor glows when the electron beam is energizing it, but it dims down almost immediately thereafter (albeit with a “long tail”, especially for the red phosphors).
An LCD, assuming no dark-frame insertion to improve motion rendering, will be illuminated for around 100% of the frame or field time, or 16.7 msec at 60p or 60i.
The upshot of all this is that the 740’s screen will render motion more sharply than an LCD but less sharply than a CRT. In practice, the razor-sharp rendering of the OLED screen and its exceedingly high contrast and fast pixel transition times makes it feel much more CRT-like than the raw numbers would imply.
Another effect is that the OLED screen is neither “on all the time” like an LCD, nor “momentarily bright then instantly extinguished” like the flying spot on a CRT. As a result, shooting the 740’s screen isn’t a matter of matching shutter speed to the screen’s refresh rate; there’s that 7 msec lag time. Put another way, shooting the 740’s display of a 1080/60p image at 1/60 captures one entire frame, plus a 41% overlap of the prior frame, and a photo at 1/125 sec captures about 90% of a frame instead of 50%:
Split-screen of 1080/60p on the PVM-740 at 1/60, 1/125, and 1/8000 sec.
The 41% overlap at 1/60 isn’t obvious in the screenshot above, but it was visible enough on my Chroma DuMonde chart screenshots, originally photographed at 1/60 sec, that I had to go back and re-do them all at 1/15 sec to reduce (though not eliminate!) the appearance of that randomly-positioned brighter band across the screen. In practical terms, this means that if you have these screens in a video or film scene, you’ll need to play with Clear Scan (on a Sony camera), Synchro Scan (Panasonic), or shutter angle / shutter speed to dial out the on-time overlap.
Even with the longer-than-CRT “on” time of the 740 (and its 17″ and 24″ brethren), many people complained about flicker, especially with 24PsF images (where the vertical refresh rate is only 48 Hz), saying it was even worse than the CRTs of days gone by. I didn’t find that the case myself, but I do note that when we used CRTs to monitor 24PsF, we did so at very low brightness levels, specifically to reduce flicker perception, and I wonder whether the folks complaining about flicker are dimming their OLEDs to a comparable level.
Also, of course, the PVM-740 allows for 20P and 25P content in addition to PsF, dropping the refresh rate from 48Hz to as low as 24Hz; something the CRTs never allowed. Those slow rates are highly flicker-prone.
No matter: there is a flicker fix available, free until the end of May 2012, for PVM-series OLEDs. It apparently lengthens the “on” time of the display, reducing visible flicker, but invariably increasing image smear during eye movements to near-LCD levels.
It’s a tradeoff, and one that’s assignable to a front-panel button, so that PVM users can use it or not as they see fit.
Conclusion
The future is here, and it’s displayed on OLEDs. Finally, we have a technology that—at least within a 30 degree viewing angle— equals and exceeds the performance of CRTs.
The PVM-740 accepts any frame rate that analog composite, HDMI, and 3G SDI can throw at it, and any video image size from 480i to 1080P. It lacks analog component and Y/C connections, true, but these are rapidly becoming redundant as even the cheapest cameras now come with HDMI ports. You should be able to hook this monitor up to anything from a GoPro to an Alexa and get a picture out of it with no problems.
True, the PVM-740 is half-res, but it’s a 7.4″ screen; I don’t know any monitors this small that offer full HD. To get close enough to benefit from a full-HD screen, you’ll be in danger of getting nose prints all over the 740’s protective screen cover.
With its small size, flexible powering, and low wattage, the 740 is well suited to field work; I ran it for the better part of a day on a single RED BRICK battery, and still had plenty of charge left (a RED ONE will drain that battery dry in under 90 minutes). The bolted-on (but removable) screen protector is a handy feature for field work, too. Given its gorgeous color and rich blacks, the PVM-740 makes a great DP’s, director’s or client’s monitor for location shoots.
As a AC’s or DIT’s monitor, the PVM-740 is a bit lacking. The CAMERA FOCUS function, while useful, is a poor cousin to the fully adjustable, colored-edging focus-assist functions on more AC-oriented field monitors. The native pixel-to-pixel mode isn’t repositionable within the image (as it is on the TV Logic LVM-074W and its companions, and in the Sony F65’s “Mag” modes). The PVM-740 is also missing many of the display modes—vectorscope, RGB parade, false-color exposure metering, zebra—that ACs and DITs appreciate on other small field monitors, even if those other monitors don’t offer the same raw image quality that the 740 has.
While its design is optimized for field work, it makes a great reference monitor in the studio or edit suite, too; it has the tonal scale, rich blacks, true colors, and local contrast that editors and colorists need. Yes, it’s not full-res, but it’s not $4,100 either (and if you need full res, the PVM-1741 and PVM-2541 are always available, along with the BVM-series OLEDs… at a price, of course!).
In summary:
– If you’re looking for the best raw image quality available today, its hard to argue against the PVM-740 or its bigger brothers. The 740 is certainly the best-looking picture available in a small (under 15″) monitor, and it’s the best-looking image available under $3690 (the street price of the PVM-1741, grin, as of 2012-03-23).
– If you need a small, portable monitor to put in front of directors and/or clients, you can’t go wrong with the PVM-740.
– If you need an AC or DIT monitor, the 740 will look utterly gorgeous, but it’s lacking in some of the bells and whistles that ACs and DITs expect on a $2700 field monitor.
Pros
- Most affordable color- and tonal-scale-reference monitor available.
- Black blacks. Seriously, really black blacks.
- Wide color gamut and multiple color spaces selectable.
- Flexible AC/DC powering; both 4-pin and V-mount DC power inputs.
- Wide range of frame rates and image sizes.
- Loop-though 3G SDI and composite inputs; HDMI input.
- Protective screen cover for field work.
- Low power consumption.
- Did I mention that the image it makes is freakin’ beautiful?
Cons
- Screen blanks for two seconds whenever WFM is toggled.
- Screen dims a bit and goes slightly blue when seen more than 30 degrees off-axis.
- It’s under-featured for a $2700 AC/DIT monitor.
Cautions
- No analog component or Y/C inputs.
- It’s “only” 960×540.
- OLED is still a new technology. Sony quotes a 30,000 hour useful life, the same as or better than a CRT, but, well, we don’t really know how the color and brightness profiles will age in the real world.
- Looking at a PVM-series OLED will spoil you for lesser displays.
More Info:
Disclosure: Sony shipped me a PVM-740, which, alas, I had to return at my own expense at the conclusion of testing.
No material connection exists between me and Sony, TV Logic, or Panasonic. No one has offered any payments, freebies, or other blandishments in return for a mention or a favorable review.