High ISO Questions

smoke665

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The advent of the mega ISO cameras being released has prompted me to read up on the subject, which in turn brings more questions.

  1. In the past there has been some discussion as to the effect a higher ISO has on dynamic range. My understanding on the new, mega high ISO cameras while not necessarily practical from a use standpoint at the maximum level, have actually raised the bar on the lower levels, making practical use of 50,000 ISO possible. While there have been improvements in the sensors, most of the increase seems to have come in the CPU and image acceleration software, which combined, limits downstream/upstream noise. My question is has the dynamic range capability improved in addition to the downstream/upstream noise reduction, or has the noise control simply created an appearance of an improvement in DR?
  2. My current K3II includes menu options for highlight/shadow correction (assume others have something similar), which can only be used at ISOs above 200 up to the camera maximum. Turning this option on, extends the s shape on either the highlights or shadows, which effectively extends the dynamic range of a JPEG. Granted it doesn't change the raw file, but it does set a flag in the metadata that will automatically apply the extended curve during development in most current raw convertors. So the question is "if you have this menu option available, do you use it on high ISO shots, and if not why"?
  3. Considering the increases in ISO, have you already or do you intend on altering your exposures to make use of the higher limits? How exactly?
I've read so many articles on the subject that my head is spinning, so I'd prefer you not post links for further reading, unless it's to illustrate your point. Looking for personal opinions and knowledge please.
 
I'll make the popcorn.
 
Subscribing, as I just bought a D500 and would like to know more about this.
 
I cut my teeth before ISO- we called it ASA.

Anything over 400 was crazy talk, and anything over 800 was obscene!

Nowadays- tech is opening a lot of opportunities. My shots of the milky way are SO simple now. I actively look for ways to exploit my camera sensor in ways to create interesting shots. This has never changed. The opportunities, however, have grown tremendously with the tech.
 
Interestingly enough, I shot at ISO 12,800 and 6400 on Wednesday of this week. Using a X-T2 and a X-Pro2 for a candlelight vigil in front of a very very dark school. I just took a peek at some of the files and they are quite usable in a photojournalistic manner. Yes, they have noise and yes, there is less dynamic range ... but as a tool to document the event they are quite useable and reflect, to a much greater degree, the tone of the event. In fact, much much better than had I used a flash. I've been shooting in low light for much of my old life. Back in the film-only days I learned how to shoot at low shutter speeds with ASA's no greater than 1600. With IS and high ISO's you can do so much more with a greater variety of lenses. Most of my shots were taken at 200mm w/ an APS-C sensors.

As to metering, in low light I always use spot and focus on the primary subject(s) and let the rest fall where they may. I shoot in RAW and I tend/try to shoot and process without the camera automatically adding anything into the mix. That's just me. In the end, the only thing that matters is the final image ... the only person(s) that cares about the path to a successful image is yourself and maybe your mother.
 
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"Practical use" is certainly a novel idea. Will it be useable for documentation? Maybe, I guess depending on what you're using the images for. Even the Sony A7s, arguably the king of current high ISO, is really only useable up to around 12,800 in my opinion, and even that depends on what you're using the photos for. The DR at higher ISOs is still not great. Try pushing your shadows on an iso10,000 shot and see how quickly things fall apart.

If my camera had the option for shadow/highlight recovery, I don't see the point in using it when all it takes is a two second curve adjustment in LR or PS.

I currently shoot all my astrophotography at ISO10k, which is very clean, but darker scenes tend to hide a lot of noise anyway. 99% of the time I'm at base ISO because the DR is best there and I'm almost always tripod mounted anyway. Your needs or style of shooting may vary. A lot of the high ISO war that's going on now between brands is purely marketing and shows almost no real world benefit, past a certain point. Who cares if your camera CAN shoot at ISO400k if the files are useless past 12,800. Yes, the advances in high ISO capability will be better with each new advance in sensor tech, and you will see better performance as "useable" high ISOs, but I cringe whenever I see the newest camera announcements with these ridiculous high ISO ranges that mean almost nothing in real world use. My 2 cents
 
The advent of the mega ISO cameras being released has prompted me to read up on the subject, which in turn brings more questions.

In the past there has been some discussion as to the effect a higher ISO has on dynamic range. My understanding on the new, mega high ISO cameras while not necessarily practical from a use standpoint at the maximum level, have actually raised the bar on the lower levels, making practical use of 50,000 ISO possible. While there have been improvements in the sensors, most of the increase seems to have come in the CPU and image acceleration software, which combined, limits downstream/upstream noise. My question is has the dynamic range capability improved in addition to the downstream/upstream noise reduction, or has the noise control simply created an appearance of an improvement in DR?

So both. Sensors have progressively gotten better (increased DR) and the processing electronics (squeeze the max out of the sensor) have gotten better. Put the two together and you get some pretty impressive performance.

My current K3II includes menu options for highlight/shadow correction (assume others have something similar), which can only be used at ISOs above 200 up to the camera maximum. Turning this option on, extends the s shape on either the highlights or shadows, which effectively extends the dynamic range of a JPEG. Granted it doesn't change the raw file, but it does set a flag in the metadata that will automatically apply the extended curve during development in most current raw convertors. So the question is "if you have this menu option available, do you use it on high ISO shots, and if not why"?

What you describe here has become pretty much standard now on most cameras and it goes by different names. There is some variation in methodology but most function as you've described. The ISO increase they require is designed to force an underexposure of the sensor and then the ISO brightening boost is withheld from the raw file which then receives special tone curve processing to produce the JPEG. Paradoxically this technique reduces DR and that includes DR in the raw file. The raw file is effected by the withholding of the ISO post processing. If you want the JPEG this method produces that's fine, but if you think you may ever want to use the raw file don't ever do this!! To answer your direct question, my Fuji has the same function. I always want the raw file and so I never have and never will use this function.

Considering the increases in ISO, have you already or do you intend on altering your exposures to make use of the higher limits? How exactly?

I recently upgraded to a new Fuji X-T2 which has the same sensor as the D500 that Destin mentions above. I have no intention of changing my exposure behavior. My goal is always the same: I want the best photo I can get and I want the most DR I can get. That goal is directly tied to exposure and improved sensors and processing in no way alters that: more exposure (up to the sensor's max capacity) = better and less exposure = worse. The sensor is a data collector with a fixed capacity. Exposing the sensor to max capacity is best and anything that isn't best is less. Circumstances at times force us to accept less -- it's always better to get the photo than not -- and when that happens I do the best I can.

Joe

I've read so many articles on the subject that my head is spinning, so I'd prefer you not post links for further reading, unless it's to illustrate your point. Looking for personal opinions and knowledge please.
 
O.K., so far I've got three kinds of popcorn; straight yellow with just a touch of butter (native ISO), black-hull with lots of real butter (high ISO) and white hull low-fat (no butter) (the lowest ISO). Put in your order and pay the lady at the end of the counter. Also if you want a special order, pay double in advance, and take a number.
 
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O.K., so far I've got three kinds of popcorn; straight yellow with just a touch of butter (native ISO), black-hull with lots of real butter (high ISO) and white hull low-fat (no butter) (the lowest ISO). Put in your order and pay the lady at the end of the counter. Also if you want a special order, pay double in advance, and take a number.
How about caramel corn, have you got any caramel corn? I like caramel corn.
 
How about caramel corn, have you got any caramel corn? I like caramel corn.
Uh, sure, but you know caramel corn is for filmies, so you'll have to show your film camera when you pick it up.

And pay double.

In advance.
 
I'll make the popcorn.

Uh oh, didn't think about this being one of those kind of posts.

@Destin glad you chimed in on the D500. It's my understanding that it comes native with ISO 52,100 and base ISO 100, then uses software to bump down to an equivalent ISO 50 and the option of bumping up to 102400, 204,800, 409,600, 892,200, 1,600,000 equivalents via camera software. As opposed to some of the others actually having native high ISO options, which supposedly has less effect on dynamic range. Have you actually had a chance to explore the high ISO options on the D500???
 
I'll make the popcorn.

Uh oh, didn't think about this being one of those kind of posts.

@Destin glad you chimed in on the D500. It's my understanding that it comes native with ISO 52,100 and base ISO 100, then uses software to bump down to an equivalent ISO 50 and the option of bumping up to 102400, 204,800, 409,600, 892,200, 1,600,000 equivalents via camera software. As opposed to some of the others actually having native high ISO options, which supposedly has less effect on dynamic range. Have you actually had a chance to explore the high ISO options on the D500???

Still waiting for it to get here so I'll let you know Tuesday haha

But I've read and watched every review I can find on the internet and the general consensus is that the "Hi" ranges are unusable and only a marketing ploy. This has been the case with every nikon I've ever owned, so it doesn't surprise me.

That being said, looking at the reviews, everything up to 12,800 and even into the high teens looks VERY good for a crop sensor, and I'm excited to see what it can do for my low light sports shooting.
 

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