REVIEW - Panasonic AG-AC90 Camcorder

For under £2,000 including tax you can get this new AVCCAM camcorder from Panasonic.ADAM GARSTONE approached the review of this new Panasonic camcorder with a heavy heart but soon began to appreciate the ‘bang for the buck’ idea behind it.

I have to admit that my heart fell a little at the prospect of reviewing Panasonic’s new AG-AC90 – yet another handheld camcorder in the PD170 style, but pulling the camera from its box I started to change my mind.

For its very competitive price (around £1500 plus VAT) the AC90 is a really nicely packaged product. It’s lighter than it looks, but is made of good quality plastics and feels like it’ll stand up to the normal levels of abuse. It’s well balanced too, whether you are holding it at eye level or low level by the top handle. The audio controls are protected by translucent, smoked plastic covers and the LCD slides away into the front of the top handle, giving it a sort of lop-sided hammerhead shark look. Overall, it looks and feels a lot more expensive than it actually is.

It’s good to see proper XLR inputs in a budget camera. There is a built-in 5.1 mic – of sorts – no-one in their right minds would be using that though, right? It’s also good to see that Panasonic have kept the top-handle zoom rocker and record button. Most of the user controls are buttons on the left side of the camera – it would have been nice to see a white balance toggle switch and, perhaps, gain, but you can’t have everything for a grand and a half.

The main LCD has a 3.5” diagonal and about 1152k ‘dots’ (whatever that means). In practice it’s bright, clear, has good resolution and, as a big bonus, is touch sensitive, so most of the User Interface features are accessed through it. The menu system is simple and clear – Panasonic are usually pretty strong in this area – and the touch screen is nicely responsive. There are Panasonic’s usual cine style matrix and gammas available, coring, knee control, skin tone detail – again, great to see on a budget camera. As well as the usual zebra, there is also a good ‘peaking’ style focus assist (red only). The eye-level viewfinder is OK, with rather low resolution but good colour and contrast – I’ve seen worse on much more expensive cameras, but there is no way to lock its position (not even detents) so it tends to flip down when you least expect it.

The lens features three, endless encoder style rings for focus, zoom and iris – very unusual in this price bracket. Interesting, you can do without the gain switch as the iris control doubles for this function. Once the iris is wide open, further turning of the encoder ring starts to up the gain. Neat.

What isn’t so neat is the feel of these controls. There doesn’t seem to be any connection between the control and what it’s controlling at all. This is particularly noticeable with the zoom ring – there are seconds of delay between turning the ring and the lens zooming. To be honest, it’s pretty close to unusable. Fortunately, the main rocker control is responsive and controllable. The lens itself has a 35mm equivalent of about 30mm to 380mm at f/1.5 to f/2.8, with really excellent optical image stabilisation.

The AC90 features Panasonic’s iA (Intelligent Auto), which turns the entire control of the camera to automatic, and the autofocus is both fast and accurate, with no hint of breathing at the long end of the lens. This is good to see, with the difficulty using the manual controls, and vital on a camera like this, which will often be used “run-and-gun”.

Panasonic have a bit of a thing about three sensor camcorders, and the AC90 is no exception, having three, 1/4.7”, backside illuminated, CMOS, 1920x1080 sensors. 1/4.7” is very tiny, but the backside illumination should help with the sensitivity and, of course, three sensors means no Bayer pattern. It’s worth noting that the tiny sensors will result in diffraction limited resolution at pretty much any aperture you set on the lens.

The sensor output is compressed using AVCCAM and recorded to SD card (there are a couple of slots). Available frame rates are 1080/25p, 1080/50i, and 1080/50p (with 576/50i, if you like that kind of thing) at data rates up to 25Mbps for the 50p. I’m generally not a big fan of AVCHD/AVCCAM implementations (the CODEC is fine, but hard to do) – though the most recent cameras seem to be getting much better. The AC90 is no exception here, with far fewer compression artefacts than past Panasonics. The image quality itself shows great tonality and colour – products of having three sensors – highlight detail in particular is beautifully rendered. Unfortunately, resolution was very poor – obviously not helped by those tiny sensors and the resultant diffraction limitations.

There are a couple of things marring the AG-AC90 – those terrible lens controls and the poor resolution – but the automatic capabilities, the lovely tonality and the overall package still make it an interesting camera, especially at the price point. You get a lot for your money.

Comments

[Lou]

"poor resolution".........not true. Sharper than my professional video camera in good lighting.

[ted]

How did you come to the conclusion that is has poor resolution? Barry Green on dvxuser states teh following: "Did I say sharp? Well, boy howdy, yes this thing is sharp. Really, really sharp. As sharp as, and perhaps sharper than, other 1080p-native camcorders I have tested. How and why? Well, part of it is because the camera uses full-resolution 1080p sensors, but they go a step further – they use a spatial-offset technique (aka “pixel shift”) to increase the resolution the camcorder can deliver, so everything internally is processed off of a 4K source image. Then it's downconverted to 1080p. And it really fills out that 1080p frame very nicely. I have to say, this camcorder is delivering some of the best chart performance I've ever tested, especially in terms of resolution with no aliasing."

[Adam]

We test the MTF of all the cameras we review, to determine the 'sharpness' of the image.

The small pixel pitch (about 2.5 um) corresponds to diffraction limited resolution of red light at around f/2.8, which probably explains the poor MTF results at apertures smaller than this.

[AC90 user]

I think you guys just got schooled by Barry Green

"It's intended to sound impressive while ignoring that fact that they're (HD Magazine) dead wrong about the results they got -- if they truly understood what they were saying, they would have made a much more responsible statement in their review. To just say the AC90 has "poor resolution" is so wrong that it's absurd. The proper statement should have read something like:
The AC90 is impressively sharp. Incredibly sharp, and in fact sharper than many other cameras we have tested that have much higher price tags. However, those results only come with apertures that are relatively wide open. All sensors are subject to their imaging softening up due to diffraction, but because of the small sensors and how many pixels are crammed onto those sensors, the AC90's diffraction limit happens quite early in the iris range. Any iris deeper than f/2.8 can show softening of the image due to diffraction; the red channel starts to be impacted by about f/2.8. Panasonic has worked around this by creating an integrated ND filter that keeps the iris in the "sweet spot" much longer than you would otherwise expect; because of the way the ND filter works, the physical iris actually stays in the sweet spot up until the iris gauge reads f/6.4. So we can report that you will have crystal clear images and razor sharp resolution at any iris between wide open (f/1.5) and f/6.4. And even then, diffraction will be of minimal impact to the image up to about f/8.0. We don't recommend using irises deeper than f/8.0, but you should get sharp images at f/8, and crystal-clear razor sharp images anywhere from f/6.4 up to f/1.5."

That would have been a responsible, informative, and useful description. Saying it has "poor resolution" is just irresponsible and factually inaccurate." Barry Green - DVXuser.com

[New AC user]

I can't find any soft scenes when using this camera. Perhaps a re-evaluation could clear up any misconceptions. My video is crisp, pristine and sharp. As a matter of fact, I lowered the detail in two menu settings. I don't understand the gibberish written by the evaluators/testers.. I am relying on what appears on my HDTV and it is NOT soft-it is very sharp. Just my thoughts.

[Marin]

Please look here :https://vimeo.com/groups/panasonicagac90/videos/56649792
and see how good are the video with this camera.

[Mikey]

I think the evaluator of the AG AC-90 needs a good pair of glasses. What soft image? Where?

[F.T.]

I think the reviewer is a rather snotty skeptic who, in true finicky british broadcasting tradition, dislikes anything that doesn't cost tens of thousands of pounds or carry a Sony tag.

"There is a built-in 5.1 mic – of sorts – no-one in their right minds would be using that though, right?"
WHY NOT? DVD actually carries 5.1 tracks, Blu-Ray 7.1 tracks, why should we skimp on the chance to at least be able to record true surround sound, or even just have more ambient tracks to use for the audio mix?

"What isn’t so neat is the feel of these controls. .. To be honest, it’s pretty close to unusable"
I tried the rings and find them PERFECT, they're a bit stiff but enough to allow precise control and a better feel than some other cameras where they are too loose - and I didn't notice any particular lag.

"the tiny sensors will result in diffraction limited resolution at pretty much any aperture you set on the lens."
That's the typical snotty engineer-type dismissal that judges cameras on paper rather than with his eyes. This camera is one of the sharpest around, certainly at this price, and several other tests and reviews have proven it. Boooo!

"recorded to SD card (there are a couple of slots)."
Oh dear, this camera really bothers you, huh? This camera has either simultaneous back-up recording or automatic roll-over and you just dismiss it with 'a couple of slots'? Again, there are no cameras with this facility in this price range.

"I’m generally not a big fan of AVCHD/AVCCAM implementations (the CODEC is fine, but hard to do)"
What exactly does this rubbish sentence mean?

"Unfortunately, resolution was very poor – obviously not helped by those tiny sensors and the resultant diffraction limitations."
AGAIN! See above, other posts here and dozens of comments around the globe.

"There are a couple of things marring the AG-AC90"
The AG-AC90 is not a top camcorder but certainly the best buy at this price; the only thing marring it is your review.

[another one]

< with 576/50i, if you like that kind of thing >

Excuse me, but if you're only delivering to DVD or the web, or mobile devices in particular, Standard Definition is more suitable as it saves a lot of hassle during production and especially post-production. The results are still very good, since you'd still be capturing from an HD sensor which the camera would down-convert in real time at the highest level. There are still plenty of SD output screens out there, so there's no reason to be dismissive about the possibility to shoot on 576i. I for one would not be happy if a camera wouldn't allow me to shoot in SD if I needed to.

[Hussain]

can we change the lens of 90 camera having the gaurantee...
Is there problem?...

[dev]

can we change panasonic ag - ac90 lence from 29.8 mm -35mm to 18mm lence ?

[Tom]

Can anyone tell me about the 25min record limit, or how much of a skip there is between changing cards, this really puts me off as I film events.