[Panasonic GH6] source for the 'minimum 800 ISO to get Dual Output Gain with stills' claim?

[FrostKiwi]

Hey there,

GH6 owner here and am really wondering, whether the claim made by this DPReview article and subsequently copy pasted by other articles can be backed up by anything.

On the GH6, Panasonic says the Dual Output Gain becomes active at ISO 800 and above. [...] So, for instance, the GH6 says that 'Dynamic Range Boost' is available from ISO 800 in stills and standard color mode, and ISO 2000 in Log video

According to this claim, in order to get Dual Ouput Gain for that extra stop of dynamic range in your photos you NEED to set a minimum of ISO 800 for in your photo mode. The 'dynamic range boost' feature is something only available for video, not for photo. No such option exists in stills mode. But this extra stop of dynamic range can also be achived in photo mode by setting a minimum of ISO 800? Without the user being made aware of that?

Where does this claim come from? There is no such mention in the official 800 page user guide. The guide even has a section for ISO thresholds:

• ISO sensitivity for still images (standard output sensitivity)
  Normal: AUTO / 50*3 / 100 to 25600
  [V-Log]: AUTO / 125*3 / 250 to 12800
  *3 When [Extended ISO] is set
  • Switchable between 1/3 EV and 1 EV steps
• ISO sensitivity for video (standard output sensitivity)
  Normal:
  [Dynamic Range Boost]
  [OFF]: AUTO / 50*4 / 100 to 12800 (base sensitivity ISO100)
  [ON]*5 : AUTO / 800 to 12800 (base sensitivity ISO800)
  [V-Log]:
  [Dynamic Range Boost]
  [OFF]: AUTO / 125*4 / 250 to 12800 (base sensitivity ISO250)
  [ON]*5 : AUTO / 2000 to 12800 (base sensitivity ISO2000)
  [Hybrid Log Gamma]:
  [Dynamic Range Boost]
  [OFF]: AUTO / 250 to 12800 (base sensitivity ISO250)
  [ON]*5 : AUTO / 2000 to 12800 (base sensitivity ISO2000)
  *4 When [Extended ISO] is set
  *5 Available for selection in the Creative Video mode
  • Switchable between 1/3 EV and 1 EV steps

No mention of such an ISO 800 threshold for stills. Did DPreview mix something up? Or is this really an invisible threshold not told to the user?

 

[Richard Butler]

Hey there,

GH6 owner here and am really wondering, whether the claim made by this DPReview article and subsequently copy pasted by other articles can be backed up by anything.

On the GH6, Panasonic says the Dual Output Gain becomes active at ISO 800 and above. [...] So, for instance, the GH6 says that 'Dynamic Range Boost' is available from ISO 800 in stills and standard color mode, and ISO 2000 in Log video

According to this claim, in order to get Dual Ouput Gain for that extra stop of dynamic range in your photos you NEED to set a minimum of ISO 800 for in your photo mode. The 'dynamic range boost' feature is something only available for video, not for photo. No such option exists in stills mode. But this extra stop of dynamic range can also be achived in photo mode by setting a minimum of ISO 800? Without the user being made aware of that?

Where does this claim come from? There is no such mention in the official 800 page user guide. The guide even has a section for ISO thresholds:

• ISO sensitivity for still images (standard output sensitivity)
  Normal: AUTO / 50*3 / 100 to 25600
  [V-Log]: AUTO / 125*3 / 250 to 12800
  *3 When [Extended ISO] is set
  • Switchable between 1/3 EV and 1 EV steps
• ISO sensitivity for video (standard output sensitivity)
  Normal:
  [Dynamic Range Boost]
  [OFF]: AUTO / 50*4 / 100 to 12800 (base sensitivity ISO100)
  [ON]*5 : AUTO / 800 to 12800 (base sensitivity ISO800)
  [V-Log]:
  [Dynamic Range Boost]
  [OFF]: AUTO / 125*4 / 250 to 12800 (base sensitivity ISO250)
  [ON]*5 : AUTO / 2000 to 12800 (base sensitivity ISO2000)
  [Hybrid Log Gamma]:
  [Dynamic Range Boost]
  [OFF]: AUTO / 250 to 12800 (base sensitivity ISO250)
  [ON]*5 : AUTO / 2000 to 12800 (base sensitivity ISO2000)
  *4 When [Extended ISO] is set
  *5 Available for selection in the Creative Video mode
  • Switchable between 1/3 EV and 1 EV steps

No mention of such an ISO 800 threshold for stills. Did DPreview mix something up? Or is this really an invisible threshold not told to the user?

The source is a briefing from Panasonic. We wouldn't have published 'Panasonic says' at the beginning of the statement otherwise.

I'm just putting the finishing touches to our GH6 review, which I hope will shed a bit more light on it, but there's already information out there that supports this claim .

Note that most cameras with dual conversion gain (ie: most modern large-sensor cameras) don't indicate which of the sensor gain modes they're in or where the crossover happens. It's only Panasonic's 'Dual Native ISO' approach in cameras such as the GH5S and S1H that makes it explicit. (From memory, the S1 didn't indicate when it switched modes until the menu option to choose modes was added in f/w 2.0).

Richard - DPReview.com

 

[FrostKiwi]

I'm just putting the finishing touches to our GH6 review, which I hope will shed a bit more light on it, but there's already information out there that supports this claim .

Note that most cameras with dual conversion gain (ie: most modern large-sensor cameras) don't indicate which of the sensor gain modes they're in or where the crossover happens. It's only Panasonic's 'Dual Native ISO' approach in cameras such as the GH5S and S1H that makes it explicit.

Thanks for clearing it up! This surprises me, that stuff like this isn't transparent to the end-user. Being a touch hyperbolic: Hear ye, every adult and child who owneth a GH6, thee shall set ISO800 as the minimum in stills mode to get an extra drop of hidden, secret sauce quality. Usually magic numbers like these are a a placebo not to be indulged, but here it's a fact with evidence. ISO800, the magic numebers that gifts one extra stop of dynamic range! (Though reading the linked chart, it seems sub ISO 400 actually beats out ISO800 in dynamic range)

Not telling stuff like this to the user baffles me, feels like an oversight. Though it doesn't completly suprise me talking about Panasonic here. Just bought my GH6 3 days ago and wanted to color match the video of my GH4 a bit easier by using V-LOG. Forgot that the GH4 had this horrendisly anti-consumer thing of paying 80$ for the V-LOG color profile unlock. Luckily it just so happens that my GH4 firmware was 2.3 and this oversight of allowing to unlock V-LOG via a software bug still works. Ohh Panasonic, you giveth and you taketh away.

 

[alcelc]

Note sure would this help:



Source: https://www.photonstophotos.net/Charts/PDR.htm#Panasonic Lumix DC-GH6

--
Albert
** Please forgive my typo error.
** Please feel free to download my image and edit it as you like **

 

[FrostKiwi]

Note sure would this help:

Source: https://www.photonstophotos.net/Charts/PDR.htm#Panasonic Lumix DC-GH6

Yeah, it's the same chart that Richard Butler linked:

putting the finishing touches to our GH6 review, which I hope will shed a bit more light on it, but there's already information out there that supports this claim .

 

[Austinian]

Note sure would this help:

Source: https://www.photonstophotos.net/Charts/PDR.htm#Panasonic Lumix DC-GH6

Yeah, it's the same chart that Richard Butler linked:

Add a G9 or GH5M2 to the chart to see what's causing some concern about the GH6 dynamic range at low ISOs.

 

[JosephScha]

OK, I did that.



G9 and GH5mk2 are nearly identical. In fact I think difference could be attributed to measurement noise. Many of the GH5mk2 green circles are entirely on top of the G9's black circles.

I have no idea what contributes to GH6 poor low ISO performance, but it is a match for the G9 and GH5mk2 once dynamic range boost kicks in until at least ISO 16000.

G9 has same dynamic range at 8000 as at 16000. Interesting:







--
js

 

[Austinian]

OK, I did that.



G9 and GH5mk2 are nearly identical. In fact I think difference could be attributed to measurement noise. Many of the GH5mk2 green circles are entirely on top of the G9's black circles.

Right. I said G9 or GH5M2. Or OM-1, etc.

I have no idea what contributes to GH6 poor low ISO performance,

Perhaps that particular sensor?

but it is a match for the G9 and GH5mk2 once dynamic range boost kicks in until at least ISO 8000.

If you don't care about dynamic range below ISO 800, no problem. That's all.