GH5 sensor readout (scan speed)...

Started Jun 21, 2017 | Discussions
_vlad Senior Member • Posts: 2,279
GH5 sensor readout (scan speed)...
11

is sensitivity related.

After discussion in another thread I did one more comparison of ES readout between GH5 and GX80. I did not believe the result in the beginning, but yes - GH5 read fast with ISO 800 and below and read slow with ISO 1000+ up to max ISO.

It is just a simple artificial light test where you can see number of stripes (flickering) related to sensor speed. I used the same lens for cameras same basic Shutter speed and prefixed ISOs. Cameras changed the AV to get proper exposure.

GX80 (G80 I suppose is same). This is consistent for all ISO from 200 up to max. So I do not post other samples.

This is GX80 1600 ISO shot using 50Hz light bulbs. You can see roughly 4 stripes which means 50*2/4= 1/25th of second readout.

GH5

ISO 800 and all ISOs below are same - as shown here

GH5 ISO 800 same setup as above shot. You see only roughly two stripes - readout is roughly 1/50s

ISO 1000 and all ISOs beyond that treshold - so again no other samples

GH5 ISO 1000, readout is roughly two times slower than in above picture and barely slower than GX80 - however this is 12bits.

As you see there is good correlation between Frederick Gluckner findings - he tested the readout at 3200 ISO - which is territory above 1000 ISO.

Now the 6K mode. Again same settings just one difference in output - result is same across all ISOs.

6K mode same across all ISO. roughly 1/50 s. Same as normal mode below 800 ISO. Sorry no exif data - captured from stream.

Now that seems to me interesting as I never thought of different readout with different ISO settings. Seems to me that Panny - at higher ISOs - has made trade-off with scan speed for better image quality.

-- hide signature --

Vlad

 _vlad's gear list:_vlad's gear list
Panasonic Lumix DMC-GX85 Panasonic GH5 Panasonic Lumix G Vario 7-14mm F4 ASPH Panasonic Lumix G Vario 100-300mm F4-5.6 OIS Panasonic Lumix G X Vario 35-100mm F2.8 OIS +5 more
Panasonic GH5 Panasonic Lumix DMC-GX85
If you believe there are incorrect tags, please send us this post using our feedback form.
DH007 Regular Member • Posts: 136
Re: GH5 sensor readout (scan speed)...

Nice work _vlad.

At the lower iso levels is the output still 12 bit?

 DH007's gear list:DH007's gear list
Panasonic Lumix G Vario 14-42mm F3.5-5.6 II ASPH Mega OIS Panasonic Lumix DMC-G7 Panasonic GX850 Panasonic Lumix DC-G9 Panasonic Lumix DC-GX9 +9 more
OP _vlad Senior Member • Posts: 2,279
Re: GH5 sensor readout (scan speed)...
1

DH007 wrote:

Nice work _vlad.

At the lower iso levels is the output still 12 bit?

Yes they are all 12bits. No difference when pushing heavily in post.

-- hide signature --

Vlad

 _vlad's gear list:_vlad's gear list
Panasonic Lumix DMC-GX85 Panasonic GH5 Panasonic Lumix G Vario 7-14mm F4 ASPH Panasonic Lumix G Vario 100-300mm F4-5.6 OIS Panasonic Lumix G X Vario 35-100mm F2.8 OIS +5 more
Robiro Veteran Member • Posts: 6,775
Re: GH5 sensor readout (scan speed)...
1

_vlad wrote:

is sensitivity related.

After discussion in another thread I did one more comparison of ES readout between GH5 and GX80. I did not believe the result in the beginning, but yes - GH5 read fast with ISO 800 and below and read slow with ISO 1000+ up to max ISO.

It is just a simple artificial light test where you can see number of stripes (flickering) related to sensor speed. I used the same lens for cameras same basic Shutter speed and prefixed ISOs. Cameras changed the AV to get proper exposure.

GX80 (G80 I suppose is same). This is consistent for all ISO from 200 up to max. So I do not post other samples.

This is GX80 1600 ISO shot using 50Hz light bulbs. You can see roughly 4 stripes which means 50*2/4= 1/25th of second readout.

About 3.5 stripes to me more precise. A 50 Hz bulb blinks 100 times a second. So, sensor readout is 3.5/100 = 0.035s, which is rounded to about 1/29s.

GH5

ISO 800 and all ISOs below are same - as shown here

GH5 ISO 800 same setup as above shot. You see only roughly two stripes - readout is roughly 1/50s

I am seeing roughly 1.8 stripes. 1.8/100 = 0.018s, which is rounded to about 1/56s.

ISO 1000 and all ISOs beyond that treshold - so again no other samples

GH5 ISO 1000, readout is roughly two times slower than in above picture and barely slower than GX80 - however this is 12bits.

As you see there is good correlation between Frederick Gluckner findings - he tested the readout at 3200 ISO - which is territory above 1000 ISO.

Now the 6K mode. Again same settings just one difference in output - result is same across all ISOs.

6K mode same across all ISO. roughly 1/50 s. Same as normal mode below 800 ISO. Sorry no exif data - captured from stream.

I am seeing roughly 1.3 stripes. 1.3/100 = 0.013s which is rounded to about 1/77s.

Now that seems to me interesting as I never thought of different readout with different ISO settings. Seems to me that Panny - at higher ISOs - has made trade-off with scan speed for better image quality.

As you, I am puzzled why this would be a case.

 Robiro's gear list:Robiro's gear list
Panasonic Lumix DMC-GX8 Panasonic 12-35mm F2.8 Panasonic Lumix G Vario 14-140mm F3.5-5.6 O.I.S Olympus 40-150mm F2.8 Pro Panasonic Leica 100-400mm F4.0-6.3 ASPH
OP _vlad Senior Member • Posts: 2,279
Re: GH5 sensor readout (scan speed)...
1

Yes the measurments here are just aproximative - however pretty much indicative what is happening below/above ISO 800. I would like to know whether other camera makers (OLY, Sony) are consistent with their sensor scan time across all ISOs. So far - AFAIK - nobody was even thinking of such a possibility (i.e sensitivity related readout).

We do not know why Panny has decided to slow down sensor read above 800 ISO (and I am pretty sure they had a reason) - maybe noise? That is a question. Fact is that while 6K photo is pretty impressive - once it get to 1600ISO or more there is more noise in captured frames - not that much (maybe 0,5 stop or even less) but it is there. And 6k photo is full speed readout.

-- hide signature --

Vlad

 _vlad's gear list:_vlad's gear list
Panasonic Lumix DMC-GX85 Panasonic GH5 Panasonic Lumix G Vario 7-14mm F4 ASPH Panasonic Lumix G Vario 100-300mm F4-5.6 OIS Panasonic Lumix G X Vario 35-100mm F2.8 OIS +5 more
Vesku Senior Member • Posts: 2,964
Re: GH5 sensor readout (scan speed)...

Thanks a lot. My biggest worry about GH5 ( slow e-shutter) is gone.

Androole Senior Member • Posts: 1,182
Re: GH5 sensor readout (scan speed)...

Extremely useful observations, and a very interesting conclusion!

I was quite shocked when I heard the early reports of such a slow readout speed, especially given that the comparable sensor generation to the ~1/60s E-M1 II. Now it's quite clear the decision that Panasonic has made to optimize the readout at different ISOs.

Glad to hear that at anything below ISO 1000 the e-shutter is totally usable in the majority of situations.

 Androole's gear list:Androole's gear list
Olympus Stylus Tough TG-850 iHS Panasonic Lumix DMC-GX7 Panasonic Lumix G 20mm F1.7 ASPH Panasonic Lumix G Vario HD 14-140mm F4-5.8 OIS Rokinon 7.5mm F3.5 UMC Fisheye CS +2 more
whumber
whumber Senior Member • Posts: 2,259
Re: GH5 sensor readout (scan speed)...
1

I'll post pictures later but it looks like the E-M1ii does the something similar except the change occurs between ISO 6400-12800.

 whumber's gear list:whumber's gear list
Fujifilm X-T1 Olympus E-M1 II Panasonic Lumix DC-G9 Olympus OM-D E-M1X Olympus M.Zuiko Digital ED 60mm 1:2.8 Macro +10 more
OP _vlad Senior Member • Posts: 2,279
Great, please do so - n/t
-- hide signature --

Vlad

 _vlad's gear list:_vlad's gear list
Panasonic Lumix DMC-GX85 Panasonic GH5 Panasonic Lumix G Vario 7-14mm F4 ASPH Panasonic Lumix G Vario 100-300mm F4-5.6 OIS Panasonic Lumix G X Vario 35-100mm F2.8 OIS +5 more
drj3 Veteran Member • Posts: 8,706
Re: GH5 sensor readout (scan speed)...
1

whumber wrote:

I'll post pictures later but it looks like the E-M1ii does the something similar except the change occurs between ISO 6400-12800.

The change in sensor readout speed with the E-M1.2 occurs at ISO 8000.

Flash:

"The sync speed for silent mode and focus bracketing (P. 94) is 1/50 second. The sync speed at ISO sensitivities of 8000 and above and during ISO bracketing (P. 94) is 1/20 second.

-- hide signature --

drj3

 drj3's gear list:drj3's gear list
Olympus E-510 Olympus E-5 Olympus E-M1 Olympus OM-D E-M10 Olympus E-M1 II +7 more
OP _vlad Senior Member • Posts: 2,279
Thanks - great info n/t
-- hide signature --

Vlad

 _vlad's gear list:_vlad's gear list
Panasonic Lumix DMC-GX85 Panasonic GH5 Panasonic Lumix G Vario 7-14mm F4 ASPH Panasonic Lumix G Vario 100-300mm F4-5.6 OIS Panasonic Lumix G X Vario 35-100mm F2.8 OIS +5 more
Dr_Jon Veteran Member • Posts: 5,848
Re: GH5 sensor readout (scan speed)...

It would be interesting to test 1080p and 4k video as well. (I'm assuming the tests other than 6k were for stills?)

 Dr_Jon's gear list:Dr_Jon's gear list
Nikon Coolpix 950 Fujifilm FinePix Real 3D W3 Sony RX100 V Canon EOS 5DS R Panasonic GH5 +29 more
drj3 Veteran Member • Posts: 8,706
Re: GH5 sensor readout (scan speed)...
1

_vlad wrote:

DH007 wrote:

Nice work _vlad.

At the lower iso levels is the output still 12 bit?

Yes they are all 12bits. No difference when pushing heavily in post.

Assuming the files are 12 bit, I would probably save RAW files, set my maximum ISO for 800 and use the Electronic shutter for most moving targets where the actual ISO would be no more than 2 stops higher and then correct the exposure in PP.

-- hide signature --

drj3

 drj3's gear list:drj3's gear list
Olympus E-510 Olympus E-5 Olympus E-M1 Olympus OM-D E-M10 Olympus E-M1 II +7 more
OP _vlad Senior Member • Posts: 2,279
Re: GH5 sensor readout (scan speed)...
2

Dr_Jon wrote:

It would be interesting to test 1080p and 4k video as well. (I'm assuming the tests other than 6k were for stills?)

Yes I was concentrating on stills performance. Testing 4k and 1080p is interesting idea though. I will try later when having some extra time. Me myself do not expect much of a difference in 4k mode - it is 50/60 FPS scanning the whole sensor area, so assume to be similar in readout (slightly better?) . Now for 1080p - I do not know what to expect performace wise.

-- hide signature --

Vlad

 _vlad's gear list:_vlad's gear list
Panasonic Lumix DMC-GX85 Panasonic GH5 Panasonic Lumix G Vario 7-14mm F4 ASPH Panasonic Lumix G Vario 100-300mm F4-5.6 OIS Panasonic Lumix G X Vario 35-100mm F2.8 OIS +5 more
whumber
whumber Senior Member • Posts: 2,259
Re: Great, please do so - n/t
1

As the other posted pointed out, the switch does indeed occur at ISO 8000.

ISO 8000

ISO 6400

 whumber's gear list:whumber's gear list
Fujifilm X-T1 Olympus E-M1 II Panasonic Lumix DC-G9 Olympus OM-D E-M1X Olympus M.Zuiko Digital ED 60mm 1:2.8 Macro +10 more
Vesku Senior Member • Posts: 2,964
Re: GH5 sensor readout (scan speed)...

_vlad wrote:

DH007 wrote:

Nice work _vlad.

At the lower iso levels is the output still 12 bit?

Yes they are all 12bits. No difference when pushing heavily in post.

I wonder what is the actual difference between slow and fast sensor reading if the both are true 12bit? Why read sensor slower?

OP _vlad Senior Member • Posts: 2,279
Re: GH5 sensor readout (scan speed)...

drj3 wrote:

_vlad wrote:

DH007 wrote:

Nice work _vlad.

At the lower iso levels is the output still 12 bit?

Yes they are all 12bits. No difference when pushing heavily in post.

Assuming the files are 12 bit, I would probably save RAW files, set my maximum ISO for 800 and use the Electronic shutter for most moving targets where the actual ISO would be no more than 2 stops higher and then correct the exposure in PP.

Agree this is obvious solution. Either limit the ISO to 800 and eventually underexpose or use 6k with full readout. Or leve it as it is - I have had rarely a real problem with 1/25s readout (GH4), but I am not denying that it might occur under some circumstancies.

Just to say - setting where the treshold is positioned is just firmware decision. I would prefer to set it to ISO 3200 or at least 1600 - even at risk of having slightly more noise.

-- hide signature --

Vlad

 _vlad's gear list:_vlad's gear list
Panasonic Lumix DMC-GX85 Panasonic GH5 Panasonic Lumix G Vario 7-14mm F4 ASPH Panasonic Lumix G Vario 100-300mm F4-5.6 OIS Panasonic Lumix G X Vario 35-100mm F2.8 OIS +5 more
OP _vlad Senior Member • Posts: 2,279
Interesting what testing target did you use?

I never saw anything like this.

-- hide signature --

Vlad

 _vlad's gear list:_vlad's gear list
Panasonic Lumix DMC-GX85 Panasonic GH5 Panasonic Lumix G Vario 7-14mm F4 ASPH Panasonic Lumix G Vario 100-300mm F4-5.6 OIS Panasonic Lumix G X Vario 35-100mm F2.8 OIS +5 more
whumber
whumber Senior Member • Posts: 2,259
Re: Interesting what testing target did you use?
2

_vlad wrote:

I never saw anything like this.

It's a monitor with a high frequency strobe.

 whumber's gear list:whumber's gear list
Fujifilm X-T1 Olympus E-M1 II Panasonic Lumix DC-G9 Olympus OM-D E-M1X Olympus M.Zuiko Digital ED 60mm 1:2.8 Macro +10 more
DH007 Regular Member • Posts: 136
Re: GH5 sensor readout (scan speed)...

Assuming the files are 12 bit, I would probably save RAW files, set my maximum ISO for 800 and use the Electronic shutter for most moving targets where the actual ISO would be no more than 2 stops higher and then correct the exposure in PP.

BOOM.

I'm looking at upgrading from the G7 where I use e-shutter a lot since I need to freeze stuff and its usually outdoors.

8bit (e-shutter read out on G7) > 12 bit - Yes!

16mp > 20mp - Yes!!

No anti aliasing filter > Yes!!!

Four times the price > F***

_________

Vlad I don't suppose you have any info on if the 180fps option for video outputs at 10bit? The options on what it does for video and what it might do are a bit hazy.

 DH007's gear list:DH007's gear list
Panasonic Lumix G Vario 14-42mm F3.5-5.6 II ASPH Mega OIS Panasonic Lumix DMC-G7 Panasonic GX850 Panasonic Lumix DC-G9 Panasonic Lumix DC-GX9 +9 more
Keyboard shortcuts:
FForum MMy threads