Sony NX80/Z90

Cliff Totten · December 22nd, 2017, 08:22 PM

So just picked up my new NX80 today and tossed it into SLog-2 to see how in looks......

Nows, I own a Sony RX10-III which uses the same 1inch-type EXMOR RS sensor that the NX8/Z90 uses. I can say that the RX10-III's SLog looks surprisingly OK at it's forced minimum 800 ISO. (It's OK but not great) So, I throw my NX80 into SLog-2 and what did Sony do? They upped the minimum ISO to noisier 1250!!....Uggg how many times is Sony going to play this game?

The Sony FS700 has it's base ISO set at 2000. This was the fundamental building block for the eventual FS7 and FS5. All three of these cameras use the same sensor and Sony FS700 raw data protocol. So, when the FS5 was released, Sony was very concerned about the sales threat that the FS5 could pose to the FS7. So,..Sony decided to raise the FS5's minimum ISO to a noisy 3200. This meant that both the original FS700 and FS7 had CLEANER SLog than the newly crippled FS5. (sad trick,...really)

As time went on and Sony was confident that the FS5 was not hurting the FS7, they decided to clean it up and lower it back to to the "original" 2000 ISO. Thank you Sony for having that change of heart and thank you for not charging us to drop it back to 2000 ISO.

Sony did it again on the A7S and A7S-II. They fearfully locked the A7S at 3200 ISO only to change their minds for the Mark II and lower it to 1600 ISO.

Now we have the same story with the NX80/Z90. C'mon guys, we KNOW you can do SLog on that sensor at 800 ISO because your Alpha division allowed THEIR camera to do it,....please put it back to 800 ISO.

Sony,...why dont you sell SLog in PAID UPGRADE tiers. Give the camera SLog 1600 ISO for free but allow us to BUY a license that will unlock 1250 ISO for $199.00. Then for $299.00, we can buy the 800 ISO firmware. If marketing protection and loss or revenue is your concern. This could compensate for it.

I'll pay it,...stop these ISO games and just give us SLog-2 at 800 ISO....uuggggg.

CT

PS,...Slog-3 has NO business being on this camera. It's downright disgusting. When you drop an 10/11 stop sensor into a 16 stop SLog-3 gamma curve. Bad idea....really bad in 8 bit!

Paul Anderegg · December 23rd, 2017, 12:33 AM

Isn't minimum ISO set to the ISO which gives highest dynamic range of the sensor, and not just some arbitrary number? I never hear anyone complaining about NOISY 2000 or 3200 Slog, only complaining that it requires more ND, an issue when shooting with a camera without built in ND filters.

Paul

Cliff Totten · December 23rd, 2017, 12:52 AM

You would think that is the case: The minimum ISO is set to the maximum dynamic range sweet spot. In theory that is correct.

In the end, Gamma curves are just "gain" on the sensor A/D conversion level. The baseline "gain" amount is how it is logarithmically sloped when it's converted to digital and sent down the pipeline for processing.

If you have a 14 stop sensor and can get that 14 stops using 2000 ISO instead of 32000 ISO, you are using less "gain" and amplification to get it. (this "gain" is not user selectable unless you are on a Panasonic "Dual Gain" camera)

Anyway, this is why Sony dropped it from the original firmware 3200 ISO down to the "proper" 2000 ISO on the FS5 via firmware update. And the A7s went from 3200 ISO to 1600 ISO.

The RX10-III with same sensor does 800 ISO. (Thank you Sony Alpha programmers)

Not sure about this but the AX700, the "sister" camera to the NX80/Z90 seems to force 1600 ISO from virtually the exact camera! (if the manual is correct)

So Sony crippled that new AX700 even harder....and it's the same damn camera, just cheaper and no handle.

Games....just marketing games with models.

Doug Jensen · January 14th, 2018, 07:08 AM

Quote:

Originally Posted by Cliff Totten

Sony,...why dont you sell SLog in PAID UPGRADE tiers. Give the camera SLog 1600 ISO for free but allow us to BUY a license that will unlock 1250 ISO for $199.00.

Cliff, could you do me a favor and double-check the base ISO for S-LOG on your NX80? On my Z90, it already is 1250.

Cliff Totten · January 14th, 2018, 10:07 AM

Wow,...I forgot all about my rant about this...lol

I think I found a firmware "bug" in the NX80.....

We all know that the reason why a log curve is set at a minimum ISO is because that ISO value is "supposed" to be where that particular sensor performs it's highest dynamic range delivery. If it was to be lower or higher, than dynamic rage begins to drop. (It's the peak of the bell curve) We of course, have found out in different models Sony likes to sometimes play games with certain camera's A/D conversion and keep that minimum ISO high...only to lower it to the "right" value at a later date. (To keep higher noise on some models and lower noise on competing sister models?)

The bug: I noticed my NX80 when in Slog under "AUTO" ISO, will force a minimum ISO of 1600. However, when you switch to "MANUAL" setting, it allows you to drop it to 1250 ISO!

We all know an Slog or Vlog rule is to never, ever shoot log at any ISO other than it's bare minimum. Raising it only hurts your dynamic range and does nothing for you anyway. So why does Sony have two different forced ISO settings in Auto and manual.?

Anyhoo,...Sony, please lower the NX80/Z90/AX700 to the proper 800 ISO that we know this sensor does in every other camera you install it in.....

Rant over...CT ;-)

Doug Jensen · January 14th, 2018, 10:25 AM

Quote:

Originally Posted by Cliff Totten

Give the camera SLog 1600 ISO for free but allow us to BUY a license that will unlock 1250 ISO for $199.00.

Seems like you owe me $199.00
I take PayPal and credit cards.

Cliff Totten · January 14th, 2018, 11:45 AM

Haha...well? That was me just being sarcastic. ;-)

The idea that you could "pay" for image quality upgrades using firmware purchasing. I hope it doesn't get that bad.

Could you imagine a camera company shipping out a new camera that is locked at no lower than +12db? (default firmware) And then that company allowing you to purchase a license to "unlock" +6db and a higher priced license to unlock true 0db?

It's an extreme idea that sounds crazy but I would not put it past camera marketing managers to have at least discussed this idea at an HQ boardroom table. Splitting camera features and creating "fake" software limitations is something everybody does. They are all guilty, some are very blatant while others are done in the most creative ways.

So for your Z90/NX80 instruction video, you might want to mention this auto/manual minimum ISO bug I discovered?

CT ;-)

Doug Jensen · January 14th, 2018, 11:56 AM

It is not a bug and it is not a "crippling" of the camera. I don't have time to get into it here, but I fundamentally disagree with almost everything you have said in the post and iwonder if you understand that the "ISO" numbers are pretty much just a bogus numbers pulled of the thin air on every camera that uses S-LOG. They mean nothing. But I think if Sony changed the menu so say "100" you'd be happy as a lark, even if nothing actually changed on the camera. When the FS5 had it's ISO scale changed, it didn't actually change anything on the camera that affected my exposure or noise levels. If you have really used S-LOG you'd know that the numbers are all smoke and mirrors. Anyway, I think you'd sleep better at night if you forget about "ISO" and were to run the camera on "Gain" the way a video camera is supposed to be used. Guess what? On Gain, all the gamma modes are "0"db. Now, that makes sense.

BTW, I've got an amplifier I can sell you that goes to eleven.

Cliff Totten · January 14th, 2018, 01:45 PM

Love your Spinal Tap reference,...my favorite comedy of all time!

Yes, I fully understand about ISO vs gain. Yes, my brain absolutely thinks in "gain", not ISO.

"0db" is just a reference point that is "assigned" at the A/D conversion point. Raw video and raw photos are all taken at "0db"...no matter what ISO you think you are choosing in the camera. They do not contain any actual gain or "ISO" in them. (only native ISO and gain metadata flags) Gain/ISO is a "POST PROCESSING" (very important...either in-camea or NLE) addition to a "0db" raw image.

ISO on digital sensors have ABSOLUTELY NOTHING to do with actual "exposure". The only thing that affects "true" exposure to light is shutter speed and iris. An image's "exposure" is 100% completed and finished before ISO/gain ever enter the equation.Your signal to noise ratio is already determined here.

However,...when an analog sensor (all sensors are analog devices) is read and the linear collection is converted and digitized, at this point, a NOMINAL gain or "amplification" amount is ASSIGNED. This value is PRE-AMPLIFIED and finally called "0db" and off that digital raw stream goes for raw output over BNC and then a copy of it goes internal processing where debayer, gamma curve, color, sharpening, ISO/gain and noise reduction is applied in-camera.

It is this early amplification for the "0db" assignment and is not at all by the user. This becomes the "native ISO" that the rest of the user controlled gain adjustments are built on top of. This "0db" is the basis for where the noise amount of the sensor is determined by Sony. Now,...ALL "amplification" affects noise...even at the earliest original A/D collection and conversion level.

So,...If Sony makes it's "0db" 2,000 ISO or 6,400 ISO or 12,800 ISO...each of these values they choose for "0db"...affect the base NOISE amount at the earliest stage of A/D conversion.

In other words, if Sony set "0db" of the FS5 at 2000 ISO, it will be CLEANER than if they set that same "0db" at 12,800 ISO or 1 million ISO. Lower ISO settings for "0db" are certainly preferred. Sony dropped the FS5's original 3200 ISO / "0db" and made it 2000 ISO for "0db" to match the performance of the FS7 and FS700. They did it for the A7S and A7S-II too. From 3200 ISO, "0db" down to 1600 ISO, "0db" and that was wonderful.

Now Doug, I already know that you are fully aware of the sensor A/D conversion process...probably even better than me. I'm simply saying this for the other readers that might not know this stuff. ;- )

Image sensor's have an inherent signal to noise ratio and a noise floor...like all analog circuits. And yes,....Nigel Tuffnell's (Spinal Tap guitar player) Marshall 12AX7 tube amp WILL sound noisier at "11" than it does at "5". ;-)

CT

Paul Anderegg · January 16th, 2018, 08:51 PM

Speaking of paying for gain reduction...if I remember correctly, the first Panasonic HPX300 cameras went out with a fixed "HIGH SENSE" mode, which for Panny and JVC (JVC calls it extended) means adding a base +6db of secret gain. They did this to nail an f11@2000 (f12@2000 PAL) rating for the camera, but after getting massive complains about the 0db noise levels, they spat out the HPX370, which allowed a "NORMAL" (JVC calls it standard) mode, which took away the hidden +6db boost, but you had to buy the new camera to get that gain reduction! On the older HPX2000 P2 cameras, the +6db boost was called "LINE MIX", and had to be assigned to one of the custom buttons. The only camera sensitivity ratings you can trust these days are Sony, because Panny and JVC rate theirs at 6db gain up. *rant off* :)

Paul

Cliff Totten · January 16th, 2018, 10:37 PM

Certainly so, Paul.

It's not really "secret gain". All sensor's are pre-amped to get the "0db" signal that a company wants. They BALANCE that "0db" to give it the best signal to noise ratio they can get for that sensor. They can also "hurt" a sensor's performance with that selected "0db" setting too!!!

There is a price to pay for everything in raw sensor collection and processing. Essentially what is "raw" sensor data? What is it in the most basic sense?

Answer = pixel (photo site) voltage readings and it's location (address) information about where it lives on the grid and a flag to tell it what RGGB color filter it sits under. Every photosite on every sensor collects photons and dumps it's voltage charge on the readout cycle.

One of the most important measurements on any sensor is it's "saturation" point. If sensor A's photosites fill up and saturate with 100 photons but sensor B's photosites are only HALF full with those same 100 photons, than B's saturation ability is much higher than A's and will absolutely have more dynamic range and signal to noise ratio potential for collection and translation.

Camera companies cant really control these "light physics" too much. They are stuck with saturation limits with completely empty photosites (pure black) and completely full photosites (pure white)....but they CAN translate and convert all the shades of gray in between. This is where rec709 and log gamma compression come into play....

Companies will collect voltage readings at every photosite and they AMPLIFY (analog or digitally) the signal that is collected...ALONG WITH THE NOISE each photosite picks up. They assign "0db" to what ever voltages they want. The price is,...the higher the collection amplification they set for "0db" the more they must deal with the side effects of increasing the noise. There is no way to avoid this. The signal to noise ratio of every photosite and every sensor is locked in place. Their '"0db" amplification setting becomes the "standard" baseline in the camera for all of YOUR chosen gain amounts that go above that.

So, setting "0db" with a value that is equivalent 2,000 ISO will be cleaner than if they set a higher pre-amp "0db" for let's say,...100,000 ISO.

This is why the FS700 and FS7 had their "0db" at 2,000 ISO rating...while they screwed the FS5 at 3,200 ISO....while using that EXACT same sensor! Luckily, Sony had a change of heart and allowed the FS5 to join it's siblings with a new firmware that set it back to where it belonged in the first place....2,000 ISO. And yes,...this changed and made the raw stream cleaner too. (the very reason why Sony did this) You can change your gain all you want in camera but your raw stream is always locked at the "0db" amplification amounts that Sony or whoever sets.

Doug is a big Sony guy (like me but he's got a few more Sony friends there than I do ;-) So, I'm sure he must know all this stuff. So, I'm confused as to why he said some of the things he said above.

Anyhoo,...back to the NX80/Z90. In auto ISO (should never use auto ISO in SLog-2 anyway) they force 1600 ISO. In Manual, you can go go down to 1,250 ISO. Meanwhile, this same RS sensor in the RX10-III / IV are allowed to go down to 800 ISO in SLog.

[sigh]....we just have to live with it unless Sony has a change of heart again....

CT ;-)

p.s. Stay FAR away from SLog-3 on this camera! Wooof,...this sensor cant handle that curve. This 1 inch-type RS sensor puts about 10.5 stops and dumping that into a 16 stop curve is NASTY! If you want your full 10.5 stops, use SLog-2 which maps only what your sensor can do from black to pure white and plots 0-255 and does not waste gamma compression on stops you don't have to begin with.

Paul Anderegg · January 16th, 2018, 10:55 PM

I feel it to be dishonest to rate a cameras specs as f11@2000 with 54db s/n, when the sensitivity figure is given for a different "gain" value than the s/n ratio figure. It is akin to a car maker quoting a city MPG with highway MPH...it's just not right. :)

On the point of sensitivity, I noticed the X70/Z90 match the X180 at wide open 18db...the X180 having an f9@2000 rating. I wish Sony would issue f@xxxx and s/n for their smaller Pro cameras. 1.7 lux means what exactly? :-P

Paul

Cliff Totten · January 17th, 2018, 12:11 AM

Yeah,...publishing signal to noise ratio of all their sensors? Hmmm...Yeah, I don't think Sony wants people judging camera's sensors with real S/N ratios numbers! lol

Once you post the S/N ratio of a sensor, that's a hard number to "market" around. Suddenly, these 1 inch-type sensors and many others wont stack up in a flattering way. Hell, the expensive FS7, F5 or F55's numbers wont touch the S/N ratio of the WAY cheaper A7S-II. That's all a little "TMI" for any marketing department to swallow.

Doesnt the X180 have three small 1/3 sensors? Dont know what generation tech they are. I'd bet they are not stacked BSI chips. It's hilarious,..Sony Semiconductor ALWAYS gives Alpha their highest sensor technology first. XDCAM usually orders Sony's older sensors and gets the newest ones last. Look at the latest FS7-II today, they are still using the same FS700 sensor from 6 or 7 years ago? It's a great sensor, OK. (I think that sensor is married to the FS700 raw protocol the FS7 uses) But Sony has advanced their sensor architecture a TON is the past 3 years only. They moved from front side to back side illuminated, stacking with actual RAM onboard. Moved form aluminum to copper conductors. And that's just the public knowledge stuff. There is allot of new secret sauce they have created that they wont tell us today.

Sony Pro even admitted that the new Venice camera has a sensor developed first for Sony Alpha division. (at least that is 2017 cutting edge)

I dunno,....funny how it works out this way.

December 22nd, 2017, 08:22 PM	#1
Cliff Totten Trustee Join Date: Aug 2010 Location: Florida Posts: 1,197	Sony NX80/Z90 - "Crippled" SLog. (again) So just picked up my new NX80 today and tossed it into SLog-2 to see how in looks...... Nows, I own a Sony RX10-III which uses the same 1inch-type EXMOR RS sensor that the NX8/Z90 uses. I can say that the RX10-III's SLog looks surprisingly OK at it's forced minimum 800 ISO. (It's OK but not great) So, I throw my NX80 into SLog-2 and what did Sony do? They upped the minimum ISO to noisier 1250!!....Uggg how many times is Sony going to play this game? The Sony FS700 has it's base ISO set at 2000. This was the fundamental building block for the eventual FS7 and FS5. All three of these cameras use the same sensor and Sony FS700 raw data protocol. So, when the FS5 was released, Sony was very concerned about the sales threat that the FS5 could pose to the FS7. So,..Sony decided to raise the FS5's minimum ISO to a noisy 3200. This meant that both the original FS700 and FS7 had CLEANER SLog than the newly crippled FS5. (sad trick,...really) As time went on and Sony was confident that the FS5 was not hurting the FS7, they decided to clean it up and lower it back to to the "original" 2000 ISO. Thank you Sony for having that change of heart and thank you for not charging us to drop it back to 2000 ISO. Sony did it again on the A7S and A7S-II. They fearfully locked the A7S at 3200 ISO only to change their minds for the Mark II and lower it to 1600 ISO. Now we have the same story with the NX80/Z90. C'mon guys, we KNOW you can do SLog on that sensor at 800 ISO because your Alpha division allowed THEIR camera to do it,....please put it back to 800 ISO. Sony,...why dont you sell SLog in PAID UPGRADE tiers. Give the camera SLog 1600 ISO for free but allow us to BUY a license that will unlock 1250 ISO for $199.00. Then for $299.00, we can buy the 800 ISO firmware. If marketing protection and loss or revenue is your concern. This could compensate for it. I'll pay it,...stop these ISO games and just give us SLog-2 at 800 ISO....uuggggg. CT PS,...Slog-3 has NO business being on this camera. It's downright disgusting. When you drop an 10/11 stop sensor into a 16 stop SLog-3 gamma curve. Bad idea....really bad in 8 bit! Last edited by Cliff Totten; December 22nd, 2017 at 11:58 PM.

December 23rd, 2017, 12:33 AM	#2
Paul Anderegg Trustee Join Date: Jan 2013 Location: San Diego, Califonia Posts: 1,559	Re: Sony NX80/Z90 - "Crippled" SLog. (again) Isn't minimum ISO set to the ISO which gives highest dynamic range of the sensor, and not just some arbitrary number? I never hear anyone complaining about NOISY 2000 or 3200 Slog, only complaining that it requires more ND, an issue when shooting with a camera without built in ND filters. Paul

December 23rd, 2017, 12:52 AM	#3
Cliff Totten Trustee Join Date: Aug 2010 Location: Florida Posts: 1,197	Re: Sony NX80/Z90 - "Crippled" SLog. (again) You would think that is the case: The minimum ISO is set to the maximum dynamic range sweet spot. In theory that is correct. In the end, Gamma curves are just "gain" on the sensor A/D conversion level. The baseline "gain" amount is how it is logarithmically sloped when it's converted to digital and sent down the pipeline for processing. If you have a 14 stop sensor and can get that 14 stops using 2000 ISO instead of 32000 ISO, you are using less "gain" and amplification to get it. (this "gain" is not user selectable unless you are on a Panasonic "Dual Gain" camera) Anyway, this is why Sony dropped it from the original firmware 3200 ISO down to the "proper" 2000 ISO on the FS5 via firmware update. And the A7s went from 3200 ISO to 1600 ISO. The RX10-III with same sensor does 800 ISO. (Thank you Sony Alpha programmers) Not sure about this but the AX700, the "sister" camera to the NX80/Z90 seems to force 1600 ISO from virtually the exact camera! (if the manual is correct) So Sony crippled that new AX700 even harder....and it's the same damn camera, just cheaper and no handle. Games....just marketing games with models. Last edited by Cliff Totten; December 23rd, 2017 at 12:35 PM.

January 14th, 2018, 10:07 AM	#5
Cliff Totten Trustee Join Date: Aug 2010 Location: Florida Posts: 1,197	Re: Sony NX80/Z90 - "Crippled" SLog. (again) Wow,...I forgot all about my rant about this...lol I think I found a firmware "bug" in the NX80..... We all know that the reason why a log curve is set at a minimum ISO is because that ISO value is "supposed" to be where that particular sensor performs it's highest dynamic range delivery. If it was to be lower or higher, than dynamic rage begins to drop. (It's the peak of the bell curve) We of course, have found out in different models Sony likes to sometimes play games with certain camera's A/D conversion and keep that minimum ISO high...only to lower it to the "right" value at a later date. (To keep higher noise on some models and lower noise on competing sister models?) The bug: I noticed my NX80 when in Slog under "AUTO" ISO, will force a minimum ISO of 1600. However, when you switch to "MANUAL" setting, it allows you to drop it to 1250 ISO! We all know an Slog or Vlog rule is to never, ever shoot log at any ISO other than it's bare minimum. Raising it only hurts your dynamic range and does nothing for you anyway. So why does Sony have two different forced ISO settings in Auto and manual.? Anyhoo,...Sony, please lower the NX80/Z90/AX700 to the proper 800 ISO that we know this sensor does in every other camera you install it in..... Rant over...CT ;-)

January 14th, 2018, 11:45 AM	#7
Cliff Totten Trustee Join Date: Aug 2010 Location: Florida Posts: 1,197	Re: Sony NX80/Z90 - "Crippled" SLog. (again) Haha...well? That was me just being sarcastic. ;-) The idea that you could "pay" for image quality upgrades using firmware purchasing. I hope it doesn't get that bad. Could you imagine a camera company shipping out a new camera that is locked at no lower than +12db? (default firmware) And then that company allowing you to purchase a license to "unlock" +6db and a higher priced license to unlock true 0db? It's an extreme idea that sounds crazy but I would not put it past camera marketing managers to have at least discussed this idea at an HQ boardroom table. Splitting camera features and creating "fake" software limitations is something everybody does. They are all guilty, some are very blatant while others are done in the most creative ways. So for your Z90/NX80 instruction video, you might want to mention this auto/manual minimum ISO bug I discovered? CT ;-)

January 14th, 2018, 11:56 AM	#8
Doug Jensen Vortex Media Join Date: Jan 2009 Location: Florida Posts: 3,416	Re: Sony NX80/Z90 - "Crippled" SLog. (again) It is not a bug and it is not a "crippling" of the camera. I don't have time to get into it here, but I fundamentally disagree with almost everything you have said in the post and iwonder if you understand that the "ISO" numbers are pretty much just a bogus numbers pulled of the thin air on every camera that uses S-LOG. They mean nothing. But I think if Sony changed the menu so say "100" you'd be happy as a lark, even if nothing actually changed on the camera. When the FS5 had it's ISO scale changed, it didn't actually change anything on the camera that affected my exposure or noise levels. If you have really used S-LOG you'd know that the numbers are all smoke and mirrors. Anyway, I think you'd sleep better at night if you forget about "ISO" and were to run the camera on "Gain" the way a video camera is supposed to be used. Guess what? On Gain, all the gamma modes are "0"db. Now, that makes sense. BTW, I've got an amplifier I can sell you that goes to eleven. __________________ Vortex Media http://www.vortexmedia.com/ Sony FS7, F55, and XDCAM training videos, field guides, and other production tools

January 14th, 2018, 01:45 PM	#9
Cliff Totten Trustee Join Date: Aug 2010 Location: Florida Posts: 1,197	Re: Sony NX80/Z90 - "Crippled" SLog. (again) Love your Spinal Tap reference,...my favorite comedy of all time! Yes, I fully understand about ISO vs gain. Yes, my brain absolutely thinks in "gain", not ISO. "0db" is just a reference point that is "assigned" at the A/D conversion point. Raw video and raw photos are all taken at "0db"...no matter what ISO you think you are choosing in the camera. They do not contain any actual gain or "ISO" in them. (only native ISO and gain metadata flags) Gain/ISO is a "POST PROCESSING" (very important...either in-camea or NLE) addition to a "0db" raw image. ISO on digital sensors have ABSOLUTELY NOTHING to do with actual "exposure". The only thing that affects "true" exposure to light is shutter speed and iris. An image's "exposure" is 100% completed and finished before ISO/gain ever enter the equation.Your signal to noise ratio is already determined here. However,...when an analog sensor (all sensors are analog devices) is read and the linear collection is converted and digitized, at this point, a NOMINAL gain or "amplification" amount is ASSIGNED. This value is PRE-AMPLIFIED and finally called "0db" and off that digital raw stream goes for raw output over BNC and then a copy of it goes internal processing where debayer, gamma curve, color, sharpening, ISO/gain and noise reduction is applied in-camera. It is this early amplification for the "0db" assignment and is not at all by the user. This becomes the "native ISO" that the rest of the user controlled gain adjustments are built on top of. This "0db" is the basis for where the noise amount of the sensor is determined by Sony. Now,...ALL "amplification" affects noise...even at the earliest original A/D collection and conversion level. So,...If Sony makes it's "0db" 2,000 ISO or 6,400 ISO or 12,800 ISO...each of these values they choose for "0db"...affect the base NOISE amount at the earliest stage of A/D conversion. In other words, if Sony set "0db" of the FS5 at 2000 ISO, it will be CLEANER than if they set that same "0db" at 12,800 ISO or 1 million ISO. Lower ISO settings for "0db" are certainly preferred. Sony dropped the FS5's original 3200 ISO / "0db" and made it 2000 ISO for "0db" to match the performance of the FS7 and FS700. They did it for the A7S and A7S-II too. From 3200 ISO, "0db" down to 1600 ISO, "0db" and that was wonderful. Now Doug, I already know that you are fully aware of the sensor A/D conversion process...probably even better than me. I'm simply saying this for the other readers that might not know this stuff. ;- ) Image sensor's have an inherent signal to noise ratio and a noise floor...like all analog circuits. And yes,....Nigel Tuffnell's (Spinal Tap guitar player) Marshall 12AX7 tube amp WILL sound noisier at "11" than it does at "5". ;-) CT Last edited by Cliff Totten; January 15th, 2018 at 02:17 AM.

January 16th, 2018, 08:51 PM	#10
Paul Anderegg Trustee Join Date: Jan 2013 Location: San Diego, Califonia Posts: 1,559	Re: Sony NX80/Z90 - "Crippled" SLog. (again) Speaking of paying for gain reduction...if I remember correctly, the first Panasonic HPX300 cameras went out with a fixed "HIGH SENSE" mode, which for Panny and JVC (JVC calls it extended) means adding a base +6db of secret gain. They did this to nail an f11@2000 (f12@2000 PAL) rating for the camera, but after getting massive complains about the 0db noise levels, they spat out the HPX370, which allowed a "NORMAL" (JVC calls it standard) mode, which took away the hidden +6db boost, but you had to buy the new camera to get that gain reduction! On the older HPX2000 P2 cameras, the +6db boost was called "LINE MIX", and had to be assigned to one of the custom buttons. The only camera sensitivity ratings you can trust these days are Sony, because Panny and JVC rate theirs at 6db gain up. rant off :) Paul

January 16th, 2018, 10:37 PM	#11
Cliff Totten Trustee Join Date: Aug 2010 Location: Florida Posts: 1,197	Re: Sony NX80/Z90 - "Crippled" SLog. (again) Certainly so, Paul. It's not really "secret gain". All sensor's are pre-amped to get the "0db" signal that a company wants. They BALANCE that "0db" to give it the best signal to noise ratio they can get for that sensor. They can also "hurt" a sensor's performance with that selected "0db" setting too!!! There is a price to pay for everything in raw sensor collection and processing. Essentially what is "raw" sensor data? What is it in the most basic sense? Answer = pixel (photo site) voltage readings and it's location (address) information about where it lives on the grid and a flag to tell it what RGGB color filter it sits under. Every photosite on every sensor collects photons and dumps it's voltage charge on the readout cycle. One of the most important measurements on any sensor is it's "saturation" point. If sensor A's photosites fill up and saturate with 100 photons but sensor B's photosites are only HALF full with those same 100 photons, than B's saturation ability is much higher than A's and will absolutely have more dynamic range and signal to noise ratio potential for collection and translation. Camera companies cant really control these "light physics" too much. They are stuck with saturation limits with completely empty photosites (pure black) and completely full photosites (pure white)....but they CAN translate and convert all the shades of gray in between. This is where rec709 and log gamma compression come into play.... Companies will collect voltage readings at every photosite and they AMPLIFY (analog or digitally) the signal that is collected...ALONG WITH THE NOISE each photosite picks up. They assign "0db" to what ever voltages they want. The price is,...the higher the collection amplification they set for "0db" the more they must deal with the side effects of increasing the noise. There is no way to avoid this. The signal to noise ratio of every photosite and every sensor is locked in place. Their '"0db" amplification setting becomes the "standard" baseline in the camera for all of YOUR chosen gain amounts that go above that. So, setting "0db" with a value that is equivalent 2,000 ISO will be cleaner than if they set a higher pre-amp "0db" for let's say,...100,000 ISO. This is why the FS700 and FS7 had their "0db" at 2,000 ISO rating...while they screwed the FS5 at 3,200 ISO....while using that EXACT same sensor! Luckily, Sony had a change of heart and allowed the FS5 to join it's siblings with a new firmware that set it back to where it belonged in the first place....2,000 ISO. And yes,...this changed and made the raw stream cleaner too. (the very reason why Sony did this) You can change your gain all you want in camera but your raw stream is always locked at the "0db" amplification amounts that Sony or whoever sets. Doug is a big Sony guy (like me but he's got a few more Sony friends there than I do ;-) So, I'm sure he must know all this stuff. So, I'm confused as to why he said some of the things he said above. Anyhoo,...back to the NX80/Z90. In auto ISO (should never use auto ISO in SLog-2 anyway) they force 1600 ISO. In Manual, you can go go down to 1,250 ISO. Meanwhile, this same RS sensor in the RX10-III / IV are allowed to go down to 800 ISO in SLog. [sigh]....we just have to live with it unless Sony has a change of heart again.... CT ;-) p.s. Stay FAR away from SLog-3 on this camera! Wooof,...this sensor cant handle that curve. This 1 inch-type RS sensor puts about 10.5 stops and dumping that into a 16 stop curve is NASTY! If you want your full 10.5 stops, use SLog-2 which maps only what your sensor can do from black to pure white and plots 0-255 and does not waste gamma compression on stops you don't have to begin with.

January 16th, 2018, 10:55 PM	#12
Paul Anderegg Trustee Join Date: Jan 2013 Location: San Diego, Califonia Posts: 1,559	Re: Sony NX80/Z90 - "Crippled" SLog. (again) I feel it to be dishonest to rate a cameras specs as f11@2000 with 54db s/n, when the sensitivity figure is given for a different "gain" value than the s/n ratio figure. It is akin to a car maker quoting a city MPG with highway MPH...it's just not right. :) On the point of sensitivity, I noticed the X70/Z90 match the X180 at wide open 18db...the X180 having an f9@2000 rating. I wish Sony would issue f@xxxx and s/n for their smaller Pro cameras. 1.7 lux means what exactly? :-P Paul

January 17th, 2018, 12:11 AM	#13
Cliff Totten Trustee Join Date: Aug 2010 Location: Florida Posts: 1,197	Re: Sony NX80/Z90 - "Crippled" SLog. (again) Yeah,...publishing signal to noise ratio of all their sensors? Hmmm...Yeah, I don't think Sony wants people judging camera's sensors with real S/N ratios numbers! lol Once you post the S/N ratio of a sensor, that's a hard number to "market" around. Suddenly, these 1 inch-type sensors and many others wont stack up in a flattering way. Hell, the expensive FS7, F5 or F55's numbers wont touch the S/N ratio of the WAY cheaper A7S-II. That's all a little "TMI" for any marketing department to swallow. Doesnt the X180 have three small 1/3 sensors? Dont know what generation tech they are. I'd bet they are not stacked BSI chips. It's hilarious,..Sony Semiconductor ALWAYS gives Alpha their highest sensor technology first. XDCAM usually orders Sony's older sensors and gets the newest ones last. Look at the latest FS7-II today, they are still using the same FS700 sensor from 6 or 7 years ago? It's a great sensor, OK. (I think that sensor is married to the FS700 raw protocol the FS7 uses) But Sony has advanced their sensor architecture a TON is the past 3 years only. They moved from front side to back side illuminated, stacking with actual RAM onboard. Moved form aluminum to copper conductors. And that's just the public knowledge stuff. There is allot of new secret sauce they have created that they wont tell us today. Sony Pro even admitted that the new Venice camera has a sensor developed first for Sony Alpha division. (at least that is 2017 cutting edge) I dunno,....funny how it works out this way.