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-   -   New JVC GY-HM70 AVCHD Camcorder (https://www.dvinfo.net/forum/jvc-gy-hm-150-100-70-series-camera-systems/514969-new-jvc-gy-hm70-avchd-camcorder.html)

Chris Hurd March 21st, 2013 04:19 PM

Re: New JVC GY-HM70 AVCHD Camcorder
 
Quote:

Originally Posted by Petter Flink (Post 1785790)
My guess is that the JVC rep and/or the studiodaily.com people just mixed something up.

Hard to say, but I'll check with the product manager about this at NAB.

Petter Flink March 22nd, 2013 12:53 AM

Re: New JVC GY-HM70 AVCHD Camcorder
 
Quote:

Originally Posted by Chris Hurd (Post 1785804)
Hard to say, but I'll check with the product manager about this at NAB.

Could be as simple as the JVC rep said "same sized sensor" which turned into "same sensor" in print.

Zach Love March 22nd, 2013 04:47 PM

Re: New JVC GY-HM70 AVCHD Camcorder
 
So I think it is pretty obvious that the chip in the HM70 isn't the same as the HMQ10. But I was still bugged by the quoted size of the chip & the FOV, so this is what I think is going on.

JVC specs say:

Quote:

Image sensor 1/2.3" 12M pixels progressive scan 1CMOS
Recording area Video 5.4M to 2.07M* pixels

....

* The 2.07M is when "Dynamic Zoom: ON."
So....

At 5.4M, with a 16:9 ratio, you have a native resolution of approximately: 3010x1743

At 2.07M, with a 16:9 ratio, you have a native resolution of 1920x1080

So it looks like that is how they get 16x out of a 10x zoom. It appears after you've run out of the 10x optical zoom, the camera starts cropping the chip from 3010x1743 to 1920x1080 for the rest of the dynamic zoom. Meaning when you have dynamic zoom enabled, you're not losing any resolution. (This is of course in theory, it'd be interesting to see how this looks in reality.)

When you use the 200x digital zoom, you're going to lose some image resolution (like any other camera with digital zoom).

Now a standard 1/2.3" is 6.17mm x 4.55mm. The aspect ratio is 4:3, which means 12M = 4000 width x 3000 height, and each pixel is then 0.0015mm x 0.0015mm.

If the pixel is 0.0015mm, then the active area of the sensor is

4.65mm x 2.61mm for 3100x1743, which is slightly smaller than a 1/3" sensor

2.88mm x 1.62mm for dynamic 1920x1080 is about the size of a 1/6" sensor

The numbers I pulled off the internet break down to this as standard sensor sizes:
1/3" - 4.8mm x 3.6mm
1/3.2" - 4.54mm x 3.42x
1/4" - 3.2mm x 2.4mm
1/6" - 2.4mm x 1.8mm

These are all 4:3, & I'm assuming the HM70 is 16:9, so the sensor active areas don't match up 1:1.

If all my math is correct then, the HM70 has a 1/2.3" chip, but only uses an active area slightly less than a 1/3" sensor, and as little as a 1/6" sensor when dynamic zoom is enabled.

My conclusion & personal opinion: I think JVC is giving misleading information to say this camera has a 1/2.3" chip, when a lot of that area isn't used.

Steve Struthers March 23rd, 2013 10:08 AM

Re: New JVC GY-HM70 AVCHD Camcorder
 
Zach Love says:

"If all my math is correct then, the HM70 has a 1/2.3" chip, but only uses an active area slightly less than a 1/3" sensor, and as little as a 1/6" sensor when dynamic zoom is enabled."

And if your math is correct, Zach, then this should mean that we will see some deterioration of the image when the camera is zoomed in beyond 16x. 1/6" is pretty tiny, and I wonder sometimes how any camera manufacturer manages to get even halfway-decent images with a sensor size that small. I know that Panasonic and a couple of others have offered cameras with such small imagers - virtually all of them consumer-grade models.

Thomas Smet March 24th, 2013 06:02 AM

Re: New JVC GY-HM70 AVCHD Camcorder
 
Guys this is nothing new. Panasonic has been doing this for awhile now. Even the GH2 has its extended tele mode where it will use the center 1920x1080 area of the chip.

What you get are basically two forms of digital zoom. One that never gets lower then 1920x1080 resolution and the other that works like a traditional digital zoom. No professional in their right mind uses digital zoom unless there is just to other choice and it fits a very specific reason.

Even the first zoom option that gets you from 10x to 16x may have a slight loss of quality. Not so much in terms of raw pixels but the fact that the image is no longer down sampled from a higher resolution chip which helps mask noise and improve detail by sub sampling. This is why it is a special. For the most part it should still look great and match what a normal video camera will look like while potentially if you stick within the 10x range it may look a bit cleaner and sharper.

If you stay within the 10x zoom range you should get a nice down sampled image that equals the noise free methods DSLRs use. Nothing misleading there at all. Think of it as a 10x zoom camera with a still great option to use up to 16x. No person after that considers digital zoom a quality feature.

Also take into consideration optical low pass filtering. DSLRs do not have this optimized for video because they need the detail for stills. A video camera on the other hand will be filtered to be optimized for video. So you may in fact get detail just about equal between 10x and 16x so they may be able to think of 16x almost as good as the 10x.

Check out some Panasonic consumer cameras to see exactly how this mode looks.

Zach Love March 24th, 2013 09:11 PM

Re: New JVC GY-HM70 AVCHD Camcorder
 
My main point of what is misleading is this:

1/2.3" CMOS chip, but less than 50% of the area of the chip is actively being used. In my opinion, you should advertise the size of the chip that actively makes video & not include any of the inactive area.

To me it is like selling a Ford Mustage with a V8 engine, advertise that it has a V8 engine, but don't clearly mention that 4 valves actually move the vehicle while the other four do squat.

Paulo Teixeira March 25th, 2013 07:26 PM

Re: New JVC GY-HM70 AVCHD Camcorder
 
This has been going on with a lot of cameras in the past. One example is the Panasonic X920 advertising the chips being 1/2.3 while it's implied that only a smaller portion of the chips is used for video.

Anyway, I sort of have mixed feelings over this. It's double the price of the PX100 (http://www.dvinfo.net/forum/digital-...d-ces2013.html) and doesn't add 24p or XLR inputs which is why I think it's few hundred dollars too much but on the other hand it does have dual battery slots which can come in handy for some applications.

Steve Struthers March 29th, 2013 03:14 PM

Re: New Camera GY-HM70U
 
Quote:

Originally Posted by Chris Harding (Post 1784031)
Hi Randy

The MC2000 has the same size sensor as the JVC and yes just a single sensor...they are not very good in low light at all but they would be OK for outdoor events. The EA-50 is a completely different camera with a huge APSC DSLR sensor ...mine give me awesome low light performance and clean gain to 24db even with the stock lens at F3.5!! I would suspect that the JVC would need a lot of lighting despite the F1.6 lens indoors ...If you want a sub $2K camera then I doubt whether the JVC would be as good as the Panasonic AC-90 but I might be wrong. For $2,000 the AC-90 is an awful lot of camera and half the price of the EA-50.

What will the JVC sell for???

Chris

Actually Chris, the Sony MC2000U has a single 1/4" sensor, while the JVC has a 1/2.3" image chip.

Yes, with just a 1/2.3" sensor, the JVC would need a lot of light to produce really clean images.

Currently, B&H in New York are selling the JVC for $1995, but it won't be available until May 15.

Given the small image sensor it has, and the fact that its EVF and LCD displays are quite low-res, I doubt that JVC will be able to command a price of $1995 for long. But this is nothing new, because camera makers always run the price up the flagpole on release to see what the market will bear, and adjust price downwards if sales don't justify the initial price. As an example of this kind of pricing behaviour, look at what happened to Sony's NX30. When it was released, it was selling for close to three grand. To get the camera to move off the shelves, Sony had to cut the price by almost $1200.00.

Non-professionals who want something better than a does-it-all-on-automatic consumer camera are quite price-sensitive, as reflected in the virtual explosion of new, low-end prosumer cameras coming in around the $2000.00 mark.

I'm thinking once initial sales figures are in, the price of the JVC HM70 will probably settle somewhere close to what the Sony MC2000 is selling for - that is to say, somewhere between $1499 and $1699. My estimation is that it's nowhere near competitive with Panasonic's AC90, which is a hell of a lot of camera for the money (and now selling for $1799 at B&H, amazingly enough). Now, that said, the HM70 will probably fly off the shelves at $1499 ~ 1599 and into its intended market - wedding and event videographers, schools and businesses with small equipment budgets.

Chris Harding March 29th, 2013 07:06 PM

Re: New JVC GY-HM70 AVCHD Camcorder
 
Thanks Steve

I did realise the the 70 chip is only a tiny bit bigger than the Sony ... My only point directed to Randy was that he might be a little disappointed with the low light performance after an HMC150 but I know Randy is hankering after a shoulder mount camera! I do agree the the weight distribution will be an issue ..with a shoulder pad right at the back and no counter balance it will be a beast to carry around all day and the physical size looks awkward too ...I shifted from my HMC80's simply because I'm getting old and weary and my back was killing me after 12 hours at a wedding with an 8lb camera ...that's why I moved to Sony's new EA-50 as it a LOT lighter and much lower profile and you can actually hang stuff off the back to balance it better ....just the 2lbs or so less weight makes a huge difference!!

Most cameras seem to be released at a slightly higher price and then are adjusted quite quickly so they fit into a competitive slot ...I can certainly see the HM70 being a very popular educational/film school camera and would suffice too for outdoor events or low end weddings ...At the usual wedding reception venues that are very low light a decent on-camera light would be an essential.

Chris

Tom Van den Berghe April 10th, 2013 01:11 PM

Re: New JVC GY-HM70 AVCHD Camcorder
 
Quote:

Originally Posted by Chris Hurd (Post 1785804)
Hard to say, but I'll check with the product manager about this at NAB.

Anybody tested this camcorder at NAB? I'm very interested in some footage of this camcoder.

Tom Van den Berghe April 11th, 2013 11:30 PM

Re: New JVC GY-HM70 AVCHD Camcorder
 
ok, I found these 2 links from NAB 2013 about this new camcorder,


and


So, anyone else tested this camcorder?

Shufiyan Shukur April 12th, 2013 04:10 AM

Re: New JVC GY-HM70 AVCHD Camcorder
 
No XLR?

- JVC PRO - JVC Professional Europe

Tom Van den Berghe April 12th, 2013 05:13 AM

Re: New JVC GY-HM70 AVCHD Camcorder
 
NO XLR but I personally don't need that. At this pricepoint a shouldercam that films 1080p is really good.
I hope the lowlight tests will be good.

Tom Van den Berghe April 16th, 2013 11:05 AM

Re: New JVC GY-HM70 AVCHD Camcorder
 
really no one tested this camcorder at NAB? strange

Steve Struthers April 17th, 2013 03:45 PM

Re: New JVC GY-HM70 AVCHD Camcorder
 
A little while ago in this thread. I predicted that JVC would not be able to keep the price of the HMC-70 at $1995 for very long. Looks like I was right. B&H are now accepting pre-orders for the HMC-70 at $1599, not the original $1995 price they were asking when the camera was first announced. This puts it smack-dab in Sony's HXR-MC2000U neighbourhood, price-wise.

Looks to me like JVC got some early market feedback on the HMC-70 and decided to drop the price.

In any case, it should be interesting to see how the camera performs in real-world circumstances.


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