ISO Invariance (ISO is Fake Follow-up)
Watch the original ISO is fake video at sdp.io/Fake
Check out the Fstoppers follow-up to our "ISO is fake" video sdp.io/FISO
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I’m actually really enjoying these technical videos. 👍🏿
Same here, I prefer a more tech focus to things.
Me too! Totally!!
Me too, Tony is the best when it comes to camera related stuff! :)
Yeah, we need series called Tony's Tech Tuesday/Thursdays.
Totally agree! I am checking this channel every single day, hoping to see a new tech vid, I wish there would be a new tech vid daily...
I SO confused ~
🤣🤣🤣🤣
😂
😂I see what you did there
Rim shot! 😄
well played Karen, well played...
Never try to out-geek a committed geek. Thanks, Tony. Your turn, @Fstoppers!
They should keep trying so that we get more of these awesome videos! :)
Tony is trolling all his critics.
shamelessly ! haha...
Every time he said "ENHANCE!", I expected him to solve a murder mystery.
You should make more videos like these, talking about the more technical stuff
🤣🤣🤣🤣
That was actually very interesting! After 7 years doing photography, I didn't know about this "ISO drop gap" ! Thank you !
I didn't know about it after 52 years! :-)
The lesson to learn here is to light your shot and not get confused by all the ' experts'
Julien, the dual-gain ISO is a relatively recent development.
I am pretty sure none of us actually did 😂😂
@@ziginox Yeah -I have nikon versions d70, d700 and D750 and they don't exhibit it in any range I'd be likely to use at all anyway... Generally speaking I prefer to screw up my images with poor focus and not have to rely on the firmware/chip to disappoint me.
I follow Tony like he's the New York Yankees in these KZhead photography controversies. They throw everything at him and he bats it away.
@jp Mariners could make him look silly?
@@JoeMaranophotography "No one cares about Micro 4 loser thirds"- Camera Conspiracies
@@JoeMaranophotography Says the guy with Lumix all over his content.
Joe Marano eeehhhhhhhh.......oooooooookkkkkkaaaaayyyyy.
As of today, he's more like the LA Dodgers and just keeps smacking homers.
Tony, I've read and viewed, including photo samples, a fair amount on ISO invariance. Yet your illustration is quite the most lucid exposition I've found.
I hope, for my sake, English is your first language
Keep doing technical, as most other otherwise knowledgeable YT channel providers often get the technical details wrong, while you are almost always correct. Thanks.
I love these videos, especially when people talk crap on other channels instead of digging into what was discussed. Fstoppers was probably the best/most fair. Well deserved victory lap! All kidding aside these videos are really what breaks your channel away from all the others. Would love to see more of these kinds of videos with one to one comparisons. And my second fav are the videos where you two are drinking and answering questions. Chelsea is a hoot!
Going for a higher iso does give you slightly less dynamic range. So it becomes a noise vs range battle. What do you guys prefer? Less noise, less dynamic range. Or more noise, but better dynamic range?
Wow! Those signal to noise drops are REALLY interesting!
Finally, KZhead guessed right about what video I wanted to watch next. This is exactly the video that I was hoping to see after watching your old video about ISO being fake. Sometimes it's your old, "evergreen" "nerdy" content that i appreciate the most.
“They did a really...good job of it.” Just say what you’re feeling Tony, I heard that microscopic pause 😂
Battle of the egos..
Well, you call this "manners" or even civilized behaviour.
😂😂😂
Nice job Tony! You tackled the issue very well, and I’m now obsessed with geeking out over those iso charts
I'm also enjoying this kind of technical video, great Tony. Expecting more.
Great info Tony. Understanding read noise at different ISO's is super useful. Thank you!
Love this kind of technical video! Really learned something. A question here: Why is there a noise drop at certain ISO?
Hi Tony, very interesting video - especially the part about the dual-gain. Wanted to ask - have you applied any noise-reduction in Lr ?
Tony - Thank you so much for this. I have the “ISO Setting/Read Noise” numerical table downloaded for my Sony A7riii to my phone for quick reference (until I get it memorized). Really enjoyed this discussion. This will give me a great deal of flexibility when shooting in different light conditions. For instance, when the sun is going down and I’m at ISO 500 but my shutter speed is not quite enough to stop the action that I want stopped; now I can jump to 1600, have slightly better quality, and move up the shutter speed to get the stop motion image I want (assuming that I have the depth of field that I desire). Options are good, I used to think that ISO had a linear relationship, now this opens up so many more options for clarity & creativity!!! Noise for my Sony A7riii: 160 = 640 200 = 800 250 = 1000 500 > 1600
I love when you make these videos! I learn something and the comments that people leave you are comedic relief lol
LOL. Right? LOL.
Thanks again Tony! Great examination and explanation.
Good video Tony. That website is very useful. It might be an idea to do a video on dynamic range tradeoff using the same website. I could imagine some people noticing the big drop at say, 800 iso for noise on a dual gain sensor, and deciding to use that as their "base iso" without factoring in dynamic range.
Tony, ignore the haters, I love technical videos. And many more people love them. Keep them up :D
Thank goodness you finally mentioned dual ISO. That was really bugging me last time.
I think this is a great topic. I’m also a computer professional and a bit of a geek... and I have been into a couple online spars with those who are rigid about ISO and it’s effects. The fear is about grainy photos and high iso... folks thinking ‘just lower the iso and it lowers the grain’. This shows that there’s a lot more to it than that and it depends on each digital camera.
This is the kind of stuff Thom Hogan is testing in his books (on Nikon cameras), which can be pretty useful if you want to get a better understanding of how your specific camera works, and how to capture optimal data. Tony is doing a great job at explaining all of this. Honestly, I think Tony is at his best when he gets to explain to a general audience something that's very technical and geeky. A lot of times, I feel like I already have a very good understanding of what he talks about, but it's always good to see how he explains it, which can make the topic even more intuitive. Great job Tony!
This is a super useful video. There are bunch of nerds who want to know about these things! Big thanks Tony!
I knew about certain ISO settings being cleaner, especially at full stop settings like 100, 400, but I didn’t realize that it was significantly different at lower ISOs for my camera. Also, this and the ISO is fake video really explains the methods you did in the “ISO doesn’t cause noise” video, which confused me and a ton of other people when you would raise the exposure to match the pictures in Lightroom. Watching these videos ahead of time would have made it make so much more sense. Glad to know that my camera is much noisier at 200 than 400, now! Thanks for these videos!
Having an A7III, you directly showed where my camera is ISO invariant. That's why after seeing Dave McKeegan's video on the topic too, I started ignoring ISO 500 entirely and sometimes even ISO 400 in the name of shutter speed. It's not often I'm even at this ISOs in the first place (usually at 100 or past 800), but it's helpful to know.
Honesty is your greatest strength. Please keep citing sources and explaining what you know v what you think. Your are a rare guy.
I love these videos tony, and I have been sticking with my D750's for so long mainly because I can shoot everything at ISO 100 (single band native ISO) and adjust gain in post, able to recover ridiculous highlights and create incredible dynamic range in single shots. Doing this in situations where HDR isnt possible (moving subjects, events, weddings) gives a unique look that clients want to pay for. A feature that should be touted on new cameras much much more.
I can't count the number of times I shot a 3-frame AE-bracketed set of a high-contrast scene with my D750 to HDR-merge later, and ended up deleting all but the "underexposed" frame because it ended up looking just as good as the 16-bit HDR merged TIFF after pushing the shadows. I never expected that when I bought it, and I've always loved that about that camera because it's so useful. I agree this should be a better-known feature because for all the talk of "ISO-less cameras" it's clear this is far from universal, and a great many consumers wouldn't even realise the significance of this very technical-sounding metric.
Fascinating stuff Tony! Thanks for sharing!
This was very inspiring! Did the test and saw some ripple on the histogram, with frequency proportional to ISO and perceived noise, gotta dig deeper.
I like the way the BMPCC4k handled the chart in their manual, it shows the same chart but with the exposure limits and illustrates that changing iso mainly changes the midpoint (within the dual gain extents)
This is very interesting info!. I'm learning my new Panasonic gh5 and wondering how does ISO effect my camera when recording video? Is it the same as when shooting pictures or does it use a different gain system for video? I'm used to my Canon XA10 video camera which is easier to understand as i knew anything above around an 8db gain setting would create visable noise.
I love these. As a kid, few of my toys remains in one piece long. Some of them returned to their retail glory, but many were learning experiences, or hangar queens.
This is HUGELY practical. I remember when I was first getting started in photography, I was shooting an amateur fight event in a place with horrible lighting. The action was fast so I needed my shutter speed up. But I couldn't go too far up because it would just be pure black. As a result I had some underexposed blurry action shots. The only ones that looked half way decent were the guys before they threw a kick or a punch, not during the action itself. Had I known that I could shoot like that and then just push my exposure in post, I would've had so many more usable shots.
but the whole point of this was, that it (usually) does not matter if you increase iso or do it in post. So during your events you could have just upped your iso... doing it in post would have no benefit
@@MsIrrealis Yeah, I'm saying I didn't understand this and why having this knowledge is so practical. I was under the false assumption that ISO at shoot time vs boosting it in post were different. And as a result I had blurry images, had I known better I would've prioritized the shutter speed more.
Tony, I love how unaffected by critics you seem. You don't seem to take things personally. It's really refreshing.
Not sure if sarcasm or........
Andrew Henderson not sarcasm.
@@andyhenderson8757 How could that be sarcasm? I mean, Tony did actually seem at ease about the whole issue and the challengers to his assertions in the first vid. Score another one for Tony. :-)
You guys are at your best with these informational videos!!! Loved the car analogy
Thank you for this video! If you were to enjoy digging deeper I’m curious why there aren’t more than two amplifying circuits built into modern cameras resulting in more “bumps” in the graph and lower high-iso noise. 😊
I love this nerd stuff! Thanks, Tony. The Photons to Photos site is extremely interesting.
Always surprised how deep you can dig in such a topic, now all is clear!
Great video. Thank you. What's the deal with iso 640 on the a7iii? I thought you start at 100 and double the number, 100, 200, 400, 800, 1600 etc etc. So should I be using 640 instead of 400 or 800? A little confused
Amaxing video! Enjoying it Love the technical info
Tony, It was very nice. This is a video for the ones curious about the machine. Its not intende to impact ones photography. So, haters, please refrain and let us, who are interested in the inner workings of the machine enjoy it.
Fan boy alert
I certainly intend for ISO invariance to affect my photography-by expanding my dynamic range up to some 6 stops.
Digital camera's have been on the market since 1997 or so , yet in all these years they still haven't fixed the iso issue .
Good follow up. Would be good to really drive home how this relates to dynamic range.
YES!!
The Photons for Photos site also includes dynamic range charts so you can see that.
@@defenderstargate1447 good to point out, it is a helpful resource for that.
I've not done any of the tests but have started to employ ETTR to good effect. I shot some pics at 6400 ISO and the images had hardly any noise - not exactly what you are talking about, but my point here is to expose correctly - as far to the right as you can - and what happens is you reduce the S/N ratio and thus noise in the darks. Shooting on a Canon 6D. Comparing these results to shooting at 100 ISO but underexposed and getting bags of noise all over the image. Metre right and push to the right.
Great video Tony! 👍 Thanks, very useful, since this is an everyday parameter we change in our cameras.
Good follow-up. The first video did seem a little off. But you have more than clarified the details here. Thank you!
Appreciate your comment on the cal mill photo during the live travel program
So here’s a question. Say I’m shooting a small event, and I want to stay in Aperture Priority so I can be fast paced. If I’m in auto iso, what should I set the min maximum at? If there’s a huge difference on the a7iii between just iso-500 vs 640, and I set the minimum to 640, I miss the opportunity to set the minimum to iso-100 for situations where there’s enough light. If I set the maximum iso too low, now I have to worry about the camera forcing the shutter speed too low.
You finally got everything correct, and corrected/pointed out the different of the test fstoppers did. We'll done Tony.
hi tony, love your videos. this is a very interesting topic!! My question is if i shoot slog2 on a7c and the base iso is 500. Does that mean i should bump it up to 640 for lowest noise and sacrifice a little DN or 500 really is the new "100" iso when shooting slog and should stick to 500? many thanks!
Thanks for putting in the research on this, Tony! Actually learned something new about ISO. Photons to Photos will be an amazing resource in researching sensor performance for me, so thanks for that as well! :D
Tony, if I check for the D7500, i see a drop at ISO400 (at a lower point than ISO200), would it be safe to say that after ISO100, ISO400 is better to use than ISO200? And after this, is it better to underexpose than overexposed? What would provide most detail? Seems we can easily bump up a stop. But clipping highlights is losing detail.
Thanks for the follow-up video Tony! One question tho, does that works the say way when shooting video? Meaning using ISO 640 rather than 500 for lower noise??
yes
Hi tony very nerdy but interesting video, i heard that using the middle isos (for example between 400 and 800) generates more noise, do you know if that is true?, Is it bette use full stops isos? I think they call it "native isos"
@Tony Can you explain why one would see negative values on the Photons to Photos Charts ? Example: Pull up the D3200 on the Read Noise in DNs vs ISO setting chart and at 100 and 200 ISO, it seems the values are negative ? Not quite sure how to interpret that. Thanks
I own a a73, the noise difference between image at ISO 640 and ISO 500 simply blow me away. Dual Gain stuff is new to me and will be thing to consider. Thanks Tony..
Love how you do your video presentation
Actually very interesting, I’ll have more control over my astrophotography results now. Thanks!
Tony, you are on to an amazing topic that so many people totatly mis understand. Can we all stop saying "ISO" and just call it what is REALLY is...."gain". Also, the term "exposure" only applies to shutter speed and aperture. "ISO/Gain" happen AFTER exposure is COMPLETED. What are we exposing image sensors to? LIGHT! Gain is NOT light. If your photosite is 50% full, 1 million "ISO" will not change that photosite's 1/2 full status!
any ideas on how the iso settings might be influenced by the other 2 parameters ? e.g. larger diaphragm lets ligt in faster, but limits the amount of time the sensor is getting to register the 'info' , versus longer exposure, where the sensor would have less light available but have relatively more time to process the information ... might this different approach influence results (obviously on raws, but still somewhat respecting the ' illumination triangle ' ) ?
Love your stuff. Please keep it up
I was the same, when I was a kid, used to take everything apart to understand how it really works ;-)
Tony, if I understand this correctly, and my main concern is noise, I should avoid ISOs 200 to 399 and jump to ISO 400 on the Nikon D850. Why is the Canon 5D Mark III so jagged? What does graph for the Canon 5D Mark III says about Canon's ISO?
Thanks for doing the X-T2 and saving me the time 😅
Great info I think it cleared up any confusion.... unlike dxo the photonstostop charts are very useful and practical.
I stopped following f stoppers when they were arguing whether a photo with the moon in front of clouds was real or fake.
And I acquired valuable facts and insights from that Fstoppers discussion.
Photons to Photos proved that for the Fuji XT3 best iso to use is : From ISO 160 until 320 The noise increase slightly but after 320 the noise is worst than ISO 800. So it's good to avoid any numbers between iso 320 and 800. From 800 to 1250 iso noise is similar. So your usable iso's will be 160 until 320 or 800 until 1250 and over that the noise always increasing. I did test my camera and that was true,couldn't believe it
thanx for this extremly usefull information Tony
I really like your technical videos...and even if something you said wasn’t 100% correct 100% of the time, it’s still fun to talk about. Any chance you could find out how to determine a safe reciprocal rule for using electronic shutter?
I would like to know if older raw converters have the same results. I know many people still use LR3/LR4 and older versions of photoshop.
Very interesting information. Thanks for sharing.
So for someone (using Sony A7iii) that doesn't want to have to push ISO a huge amount in post (lots of extra time involved), the best way to work is that if I can't shoot at base ISO of 100, I should go straight to 640 rather than bothering with anything between the 200 and 500 range?
Followed what you said Tony with test on my A7iii all comes out just as you said even the drop off between 640 and 500, But what I dont get is after a few more tests using the same Tamron 28-75 at 75mm if I take 1 shot at iso 8000 at 2.8 1/640sec correct exposure its clean use same iso 8000 at 2.8 with 1/8000th sec and match the total exposure is full of noise am I missing something here? Anyone. Should this not give equal results?
Maybe it is time to change our vocabulary. For instance, new light emitting diode (LED) light bulbs now lists Lumens and their Watts equivalent. Lumen is the actual measure of light (that is produced by the bulb) but there needs to be a translation to the Watts-equivalent that we are all used to for incandescent bulbs. So maybe we need to learn new terms like signal-to-noise ratio and signal gain, while also showing the equivalent in photographer-speak, like stops of noise and ISO (respectively). It reflects the actual physics of semiconductor sensors, while also bridging to the 100 year old nomenclature created in the chemistry-based film days. As we transition to using both sets of vocabularies, it will become more comfortable, and also make more sense. Thanks for these and other videos, Tony and Chelsea.
The ISP drop gap is great info. I now know the lowest ISO on my camera is not the best, and 1 stop higher is better. Thanks!
So if it is too dark to use base ISO. It is better to underexpose, so the histogram should be on the left. You don't risk to loose any information about the highlights and you know you can raise shadows without loosing anything too. Different thing if there is enough light to use base ISO. In that case it could be better to expose to the right, to have lower noise in the shadows.
Yes, curious minds would like to know. Thanks, Tony and Chelsea!
Ha, that Photons to Photos thing is really interesting. On my 5DII, through experience I'd found ISO 800 to be a sweet spot, and checking the chart I see that's just before the point where noise goes linear and where lower ISOs are up and down and don't offer much. Thanks for that, Tony.
Ooh, and my Fuji X100F (which I haven't had long enough to get to know properly yet) has that dual gain dip at ISO 800, so 800 seems to be a sweet spot for that camera too.
Thank you for the link to photons to photos. I looked up my 80D And found a chart. It has no great big gaps. But I found iso-129 is more likely to cause noise then iso-159. Very interesting. Good information. Thank you
Looking at the Read Noise graph for the a7iii, does ISO50 produce (ever so slightly) less noise than ISO100? Even though it's an 'extended' ISO and not base? And - more interestingly - does ISO640 produce less noise than ISO400, and even ISO200?
I never leave comments on KZhead, but this video is so good that I had to tell you! These technical videos are my favorite, might be because I’m an engineer :D
TOTALLY WORTHWHILE! Just like knowing how a clutch/shift works on your car, allows you to drive it better. Knowing some of the things you revealed (some things I had no idea about!) certainly helps. At least those of us that don't live in AUTO world. Thanks.
Push gas, go, every car is the same..... Great analogy
So, based on your first video on this topic, I did a test. I live in Cleveland, and we have a magnificent art museum that is free. I've photographed many of the statues in there before, oftentimes trying to get the slowest shutter speed I could without camera shake (Sony's IBIS helps a lot). These made for a useful subject of comparison. THIS TIME, I went in and purposefully underexposed most of my images by about two stops, which made getting photos without shake a relative breeze (again, thanks IBIS). On my older camera, an A7II, this would have resulted in an amount of noise I wasn't happy with. Of course, I knew the A7RIII's sensor would be better (that's why I spent the money to upgrade), but I was really shocked by the results I was able to get by pushing the exposure in Capture One in post. I also took some shots at higher ISOs which were "properly" exposed, and the amount of noise was virtually indistinguishable. In situations where I'm shooting something I HAVEN'T already done several times before, I will try to get closer exposure, as both version had SOME noise (though much much more manageable than before), but it's nice to know now that when I'm in a pinch, I now have a little more latitude in using a faster shutter speed and underexposing than I thought I did. So thanks for inspiring me to do some more experimenting with my gear. Hopefully, I'll have less blurred shots in the future to show for it.
Absolutely Fabulous Video Really Appreciate!
Super useful! Going by the photons to photons chart, it's better to use ISO 800 than anything between 320-640 on my X-Pro2. I will put that into practice.
Keep in mind to cross reference it with the dynamic range chart on the same website.
@@Thebrodelicious Thanks for that, looks like between 2/3-1 stop difference in dynamic range between ISO 320 and 800. Doesn't seem too bad. For DR critical work (like landscapes), I'd be using base ISO anyways.
Thanks Tony a lot of work!!! I like doing night shots and the point of the ISO Invariance is basically for the night. The lower the ISO the less blown highlights. I have the A7M3 and do Milky Ways, I can shoot 800 upto 51200 with no difference in noise but below 800 there is more noise (why who knows!) But if doing night cityscape with bright lights shoot at 800 to prevent blown highlights and raising shadows brings out detail in shadows. Also if shooting a sunrise/set shoot at ISO 50 and in post raise exposure to get rid of the blue in shadows like white boats being bluish due greyscale. But I see so many youtubers not use the benefit properly like comparing 100 to 800 sure 100 is noisier due to camera processing but 800 up is awesome like the A7S is a night monster when dealing with noise but not ISO Invariant But if you put a 12MP backlit sensor in and Invariant oh! how sweet!!! Yes you need to get to some dark sky do some Milky Way and compare or a cityscape in studio you can not really show the ISO Invariant benefit, just get under some stars. Oh and I do know that higher ISO also lets you shot faster with a larger f/# for that greater depth but a different issue!
Very good informative video! Though imo you should have mentioned ISO invariance in your "ISO is fake" video too. Thank you for clearing this up!
You're so nerdy and I love it!
Why did you not try the other cameras from their drop off point? I own a t-t2 and happen to know that the drop related to dual gain lays around iso 800, so is you compared between 800 and 12800 or something the difference would have been minimal.
Also there is a question always popping up in my mind, kind on this topic if you can help.. if I set my camera to record photos on a lower mp. 12 instead if 16 for example. Will my full image, no zoom, have less noise visible. What I am asking is, is it worth it. 6d and 6d2 appears to have exactly the same sensor and because 6d2 is more MP it has a bit more noise. Which if what I suggest is true means that if I use a 6d2 with lower MP I will have similar final results. Hope I do make sense, and find an answer :) cheers
Are 12 bit cameras and 14 bit cameras directly comparable? My 90D appears to have more noise than my old 1000D within the common ISO range, according to Photons to Photos
WOW.. just thank you. After owning myb6d for like 6 years or so, suddenly make sense why I find iso 2500 so suitable. It is really kind of funny but also a really good bit if information for looking on a new camera..!! Thank you again :)
Just curious if you checked to see if the cameras change the excitation voltage on the sensor. It is my understanding that being able to precisely control the excitation voltage (gain) is what made the digital camera possible. My guess is that there was testing where they found what you did where manipulating the ISO with software and stepping the excitation voltage to sweet spots made more sense.
Good job. You are learning. Astronomers have known this for years. Look up photon to electron exchange. The camera counts electrons, not photons. Yes, photon kick of the electrons that are counted. When you turn the ISO up the number of photons to electron ratio is read differently. So when you have a low photon to electron ratio you have the limit to how high the ISO should be set. One photon to one electron counted.
Ok. so for my D850, I should either shoot below ISO 150, or above 400 based on photonstophotos. Great info.
Also check their dynamic range charts, you may reduce noise by dropping the iso but you'll probably also loose dynamic range.