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Comment by formerly_proven | Hacker News Reader

Real cameras have been doing "HDR" for ages, since their sensors have 12-14 stops of dynamic range, but JPEG only has 8. And it works incredibly well, just like the color science Nikon and Canon have figured out, a thing smartphones are lacking as well. With a lot of light smartphones can take very good pictures as far as resolution is concerned, but color and dynamic range rendering are consistently poor. For me it's rare that I need to change the colors my Nikon camera produces, and if I do, it's usually just a slight tweak (a few hundred Kelvin of red-blue shift or maybe a tiny magenta-green adjustment), while the colors in practically every iPhone shot are lacking and require effort to get to a satisfactory level.

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That doesn't sound right at all. DSLRs like my Canon do indeed have a larger dynamic range but they are still nowhere near being close to the dynamic range the human eye can capture. Moreover, the native image rendered by DSLRs still has a linear transfer function that still suffers all the issues that HDR tries to solve. This is why auto-bracket exposure is a thing on all DSLRs so you can try to capture high dynamic range scenes in multiple photographs that you then need to combine offline in separate software.

And the sad fact of the matter is that computational photography on phones, especially when it comes to HDR, makes it absolutely no hassle to obtain exceptionally good HDR captures 80+% of the time. I've literally taken back to back comparison shots of my son on a bright sunny day on a boat when on the ocean and my smartphone picture (S9+) was far superior to my DSLR image, even after trying to capture details from highlights/shadows in postprocessing.

Phones these days can perform a lot of neat tricks to reduce noise, capture large dynamic ranges and compress it all into a pleasing HDR image in fractions of seconds that lets you achieve great HDR images even with moving subjects (something notoriously hard with a DSLR).

Not that DSLRs don't have a whole host of other advantages when it comes to image quality and depth-of-focus, etc, but HDR is not one of them. It is almost the sole reason why I've been reaching for my DSLR less and less when on vacation.

The DSLR captures pictures and then you post-process them. The phone can dynamically adjust what it captures, and potentially capture way more data (quickly slurping a gigabyte of image data into RAM) than a DSLR can push to persistent storage in an acceptable timeframe.

Together with the phone always being in my pocket, while a DSLR is bulky, I've gone completely with the phone. I just wish the computational photography developers and the camera engineers would come together and make something that uses the far superior hardware of the DSLR combined with the far superior software originally designed for phones.

Yeah, it's a similar situation for me. Though large prints from phone photographs are pretty poor in comparison to the image quality from even my entry-level Rebel Xsi from 2007. Sports photography with a good lens is still something that a camera phone will never rival, but in most day to day situations, it has surpassed DSLRs purely out of convenience and being good enough (and in the case of things like HDR/low-light photography, better than a DSLR in many situations).

> Moreover, the native image rendered by DSLRs still has a linear transfer function

Capture RAW+JPEG of a scene with dark shadows and bright highlights, the camera clearly isn't using a linear transfer function to get from RAW to JPEG. With something like a D7200 you can literally have the sun in your picture and still get both detail in the sunstar and the clouds, while also having detail in the sun's shade, with an out-of-camera JPEG.

That isn't the same type of HDR that these HDR modes on cell phones are. You seem to be confusing bit's with stops of dynamic range.

To simplify I'll pick a grayscale image so with 8bits you would only have 0-255 as pixel values for the intensity.

With 12 bits you'll have 4096, and so forth.

What cellphone HDR usually does is take the image at a high exposure and a low exposure and combine the result. (Also the sensors inside the cellphone are also more than 8bit)

Even if you take a 12 bit photo if it's overexposed you can't do much. All you get is more play but it doesn't solve the fundamental problem of too much light hitting the sensor, or vice versa if the image is underexposed.

Now there are more advanced camera sensors that let you set the exposure time (or usually the ISO (which just translates to gain) at specific horizontal points of the sensor so that you can get even better images in one frame.

> You seem to be confusing bit's with stops of dynamic range.

This is correct, they seem to be mistaken. I've seen this mistake many times in this thread. I wrote a comment in reply to one of them explaining in some detail what the point of higher bit depths and "HDR" (as a set of technology standards) is: https://news.ycombinator.com/item?id=24044818

Your remark (~"x bits worth of luma doesn't necessarily correspond to x stops of DR on a display") is entirely correct but is tangential to my point. You can't encode a scene with more than 8 stops of dynamic range into an 8 bit JPEG without either loosing details or performing a tone-mapping-like process.

> That isn't the same type of HDR that these HDR modes on cell phones are. You seem to be confusing bit's with stops of dynamic range.

I'm aware of the difference between bracketed HDR and what these cameras do, but that's besides the point. If you capture RAW+JPEG it's pretty obvious that the camera is not using a flat curve, but that it is quite clearly doing something similar to tone mapping around highlights and shadows, and it's not fixed either, but slightly different for each shot.

Have you tried Pixels? To my taste the photos they take are a couple notches better than iPhones.

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