JVC GY-HM200 - alternative to Sony PXW-X70

[Andreas Jaeger]

I have since Monday, the JVC GY-HM200.

Here is the link to JVC read the specs and features:
http://pro.jvc.com/prof/attributes/f...l_id=MDL102319

Have not "worked properly" I'm still trying and adjust.
And the first project will be available as HD camera.
As 4K camera then it will certainly filming in April or May of me.

My points that have the GY-HM200 for me as Alternatve for Sony PXW-X70:
- Bigger / more control knobs
- Focus ring / zoom ring / aperture wheel
- Remote as LANC (yes, the "right" with 2.5 mm jack) / no two adapter from Multi-interface / to AV-R / to 2,5mm. My existing Manfrotto remote works fine on both the Canon XA-25 as well as the GY-HM200
- Good light sensitivity (just as well as my XA25)
- "4K upgrade." (Cf. to PXW-X70) is already included.
- Data Rate 4K 150Mbit! (PXW-X70 only 60Mbit / 100Mbit AX100)
- HD 4: 2: 2 with 50Mbit
- Remote via WIFI or LAN included (without app download)
Etc. Included Streaming Youtube to U-Stream -
- Colors / contrast / look are "out of the box" very good / like my Canon XA25.
- Standard battery runs (in HD) 5hrs! 4K in 4.5 hours.
- Other details

Greeting
Andreas

[Paul Anderegg]

Andreas, I looked into the X70 for replacement of my X70, for the same features (manual controls most important) you listed.

You mention it is very good in low light, but I am pretty sure that is only at wide angle. At wide angle, the lens is rated at f1.2. At telephoto, that drops to f3.5. That is a 3 stop drop from wide to telephoto. Each stop of light loss requires 6db of gain to maintain brightness, so that would mean 18db of gain must be added when zooming in from wide to telephoto to maintain picture brightness!

Can you confirm if this is in fact true?

Danke! :-D

Paul

[Tim Paynter]

I am so glad someone bought one of these on this forum so we can see some comparison footage or at least an independent point of view.

Andreas, by chance, can you post one of your test shots?


Thanks,

Tim

[Andreas Jaeger]

Originally Posted by Paul Anderegg

Andreas, I looked into the X70 for replacement of my X70, for the same features (manual controls most important) you listed.

You mention it is very good in low light, but I am pretty sure that is only at wide angle. At wide angle, the lens is rated at f1.2. At telephoto, that drops to f3.5. That is a 3 stop drop from wide to telephoto. Each stop of light loss requires 6db of gain to maintain brightness, so that would mean 18db of gain must be added when zooming in from wide to telephoto to maintain picture brightness!

Can you confirm if this is in fact true?

Danke! :-D

Paul

Hello Paul,

Yes its true that f1.2 is for Wide Angle.
And down to f3.5 at Telephoto.

BUT:
Its the same light sensitivity as my XA25 is on Telephoto with f3.5.
On Wide Angle (f1.2) the HM200 is better then my XA25!

So if you will have the "Same Sensivity" as the XA25 you can put at Wide Angle an f3.5 and have "no ramping" to max Telephoto (12x).
Or vice versa its good as the XA25, and with more sensivity at Wide Angle....

Greeting
Andreas

[Andreas Jaeger]

Originally Posted by Tim Paynter

I am so glad someone bought one of these on this forum so we can see some comparison footage or at least an independent point of view.

Andreas, by chance, can you post one of your test shots?


Thanks,

Tim

Hello,

yes i can post some Test Shoots but early next week.
This week and Weekend i'm very busy with The HM200 first Job....

[Paul Anderegg]

I can see the HM200 as a great daylight camera. Being the "same sensitivity" as the XA25 is a good indicator for daytime performance, but as I found with my X70, the lens limitations and gain up noise take a toll.

The XA25 matches the X70 at 18db in low light when the XA25 is at f1.8 and the X70 is at f2.8. In the end, the X70 can add 9db more gain, so it outperforms the XA25 in the dark. The HM200 would be at an EXTREME disadvantage against the X70 at night given your comparison with the XA25.

It really is a disappointment, because if it had the same 1 stop iris ramping as the X70, it would be the perfect camera for me and I would trade in my X70 for it. :(

Paul

[Andreas Jaeger]

Hello Paul,

do you have an direct comparison between the X70 and the XA25 /20 (so do you have both)?

Here in this forum in an X70 Thread someone made (a Wedding shooting) a direct comparison.
And the difference between XA25 and X70 are not 18dB.
On his comparison there was only a little (i think 6dB)....
But i dont find the thread...

If its true that XA25 is 18dB more Gain nessesary (to the X70) then ok is the HM200 also less sensitive...

So its your decision...

Andreas

[Paul Anderegg]

Sorry for the misunderstanding. The X70 can GAIN UP 9db more (33db) than the XA25 (24db). The 18db reference is how the XA25 and X70 compare in the YouTube video below, when each is set to 18db wide open iris.

Obviously, if the X70 can gain UP an extra 9db, that is an extra stop and a half of brightness that can be added to it's picture.

Low light / gain: Sony PXW-X70 camcorder vs Canon XA20 & XF200, and Sony PMW-200 - YouTube

[Andreas Jaeger]

Hello Paul,

ok i understand.

but how grainy is the X70 between 24dB and 33dB?
Is this in practice accceptable?

Andreas

[Joachim Claus]

Paul, with all respect, however I have the impression, that you are a little biased against JVC camcorders. Your calculations regarding the drop of sensitivity from f=1.2 to f=3,5 is indeed 18dB (JVC), while the drop of sensitivity from f=2.8 to f=4.5 is 8dB (Sony). However this is only part of the story, as the absolute light sensitivity of the JVC lens (f=1.2) and the Sony lens (f=2,8) shows a difference of 14.6dB in favor of the JVC lens. With other words, the Sony lens has a sensitivity difference at its widest iris of 14.6 dB. If you take this difference into account, the loss of the JVC from wide to tele (18 dB) needs to becorrected by 14.6 db if you compare absolute light sensitivity with the Sony X70.

The little graph underneath shows the relationships in a simple way:


-----JVC range 1.2 - 3.5
-----|------------------------------|

------------------------------Sony range 2.8 - 4.5
------------------------------|--------------|

1.0------1.4------2.0------2.8------4.0------5.6------8.0...

0dB-----6dB-----12dB---18dB---24dB---30dB---36dB each step drops light by 6db

In the comparison of the two camcorders one would have to add the light sensitivity of the CMOS chip. Assuming, that both camcorders have the same net number of pixels to represent 4K resolution, the Sony with its 1 inch sensor has about a fife times larger sensor surface compared to JVC with its 1/2.3 inch sensor. With up-to-date CMOS technology of both companies, this would give the Sony a sensitivity benefit of 14.5 dB (if both camcorders would have the same lens characteristics). As they have not the same lens characteristics (compare the above calculations), the Sony overcomes its sensitivity loss of 14.6 dB due to its smaler lens aperture by the gain of the larger CMOS chip of 14.5 dB.

Taking all this theoretical discussions, I would prefer to see a fair comparison of the two camcorders under identical low light conditions to get a "real-world" result.

Joachim

[Andreas Jaeger]

Hi,

good Speaking, Joachim. (ah aus der Frankurter Ecke - komme aus Stuttgart / Ludwigsburg).
Only a real world Test is the right way.

Because you dont know if that the JVC Sensor is better (than X70 Sensor).
Because the HM200 is brand new and the X70 (so the little Brother AX100) is more than One Year old.

So it CAN be possible the newer Sensor on the HM200 outperforms (in sensivity) the X70 Sensor...
...who knows?

Andreas

[Paul Anderegg]

JC, Andreas stated that the HM200 is similar to the XA25 at identical aperture, f3.5 in his comparison. In the YouTube video above, the XA25 at f1.8 matches the X70 at f2.8. Given that data, the X70 can expose 1 and 1/3 stops (8db) more light than the XA25, if it could open from f2.8 to f1.8, you would be able to observe that better. Since the HM200 can open up 6db of iris more than the XA25, the X70 would still have a slight db advantage wide open? My brain is swimming with f-stop conversions now, it feels like a stroke.

Regardless, all math aside, if the HM200 is similar to the XA25 at "workimng iris" stops, then it would have to turn into an A7s with that f1.2 apature. You can't have great XA25 sensitivity stopped down without insinuating that the darn little thing gets 18db BRIGHTER at wide open.

More math please, and Andreas, we loo forward to a direct gain by gain comparison of the HM200 vs XA25.

Paul

[Kevin Balling]

FYI. The JVC GY HM200 is finally "In Stock" at B&H. I am anxious to see some footage.

[Andreas Jaeger]

Originally Posted by Paul Anderegg

JC, Andreas stated that the HM200 is similar to the XA25 at identical aperture, f3.5 in his comparison. In the YouTube video above, the XA25 at f1.8 matches the X70 at f2.8. Given that data, the X70 can expose 1 and 1/3 stops (8db) more light than the XA25, if it could open from f2.8 to f1.8, you would be able to observe that better. Since the HM200 can open up 6db of iris more than the XA25, the X70 would still have a slight db advantage wide open? My brain is swimming with f-stop conversions now, it feels like a stroke.

Regardless, all math aside, if the HM200 is similar to the XA25 at "workimng iris" stops, then it would have to turn into an A7s with that f1.2 apature. You can't have great XA25 sensitivity stopped down without insinuating that the darn little thing gets 18db BRIGHTER at wide open.

More math please, and Andreas, we loo forward to a direct gain by gain comparison of the HM200 vs XA25.

Paul

Hi Paul,

On Friday i have a chance to make a small side by side comparison.
I will take some Photos from the LCD-Screen (from HM200 and XA25) with an "Test Scenario" that i "have constructed".
And an Frame of this "Test Scenario" from the Footage as a Full-HD Picture

Videos on Youtube can i get earliest next week.

So please be Patient...

Andreas

[David Johns]

Hello,

I'm due to get an HM200 on loan from JVC for test purposes in the next week or so; happy to do some comparisons / answer any queries etc as well.

My X70 long ago went back to Sony's PR co but I've still got my XA20 so I'll happily do a comparison.

Regards
Dave