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iPhone camera app replaces person’s head with a leaf in photo

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Re: iPhone camera app replaces person’s head with a leaf in photo

#401

Post by eezurr »

tsimionescu wrote: post #337
max48 wrote: post #329

Earlier quoted context omitted.

>The quality that comes out of phone cameras is remarkable It's more than that, it's completely mind blowing when you compare it to a DSLR. In "good" lightning condition, your iphone will give you a picture 75% as good as what you could get with a 4k$ fullframe DSLR kit that's 10" long and weight a few pounds. the problem is when light is not perfect, that's when the bigger lens/sensor are worth it even for a beginne…

> the problem is when light is not perfect, that's when the bigger lens/sensor are worth it even for a beginner that doesn't know much about photography. I think the opposite is true, from my (amateur) experience. It's much harder to get a good photo in poor light with a dedicated camera if you don't know what you're doing than it is to get a good photo with a smartphone. In good light, the better sensors shine throu…

Snapping good low light photos really comes down to how fast your lens is (smaller f stop number). A lot of kit lens (the ones sold with cameras, even nice cameras), are surprisingly low quality lens, and don't really open up much. My Sony A7-3 came with a kit lens that opens up to F3.5.

This summer I purchased the 24mm GM F1.4 and WOW does it take fantastic night photos. No tripod needed, it lets in enough light that I can use 1/30+ shutter speed. https://i.imgur.com/CcNEUsM.jpg (photo I took recently. 1/40s, 1.4F, 1250 ISO. No photoshop magic, just basic lightroom adjustments)

Also, the iphone opens up to 1.4f, so you're probably not making a fair comparison to your camera (assuming your lens does open up as much)

EDIT: Sony has a 1.2F 50mm lens I really want to get my hands on, but now I am an entrepreneur so my spending days are over for awhile.

Re: iPhone camera app replaces person’s head with a leaf in photo

#402

Post by sudosysgen »

tagoregrtst wrote: post #391
sudosysgen wrote: post #326

Earlier quoted context omitted.

Film development is actually VERY, VERY far from linear. Because of film grain, it's not continuous either, but actually discrete too.

Film development is very non linear in the exposure (call it z dimension), not in the dimension (x and y). That is to say it might exaggerate or diminish a gradient that was already there but not create one from nothing. The grain is random size and randomly distributed which cancels out a lot of the effects of discritzation (eg you wont get patterns due nyquist sampling error).

It's non linear in the X and y dimension because of grain.

Any camera with a good antialiasing filter will also have little to no discretisation error.

Re: iPhone camera app replaces person’s head with a leaf in photo

#403

Post by Jenda_ »

So… when are we going to see made up numbers in photographed documents again? https://www.dkriesel.com/en/blog/2013/0802_xerox-workcentres...

Superimposing other's people face onto a photo from a crime scene?

Or, as part of my work, I photograph electric switchboards for documentation and diagnostic purposes. Hopefully I won't get any hallucinated connections, right?

Re: iPhone camera app replaces person’s head with a leaf in photo

#404

Post by maxerickson »

CarVac wrote: post #305
mc32 wrote: post #177

Earlier quoted context omitted.

They need to offer an option for a "raw" image as they used to be called --which were minimally processed and were not compressed.

The problem with phone raws is that either: 1. They're not raw, they're aligned and merged and denoised and sharpened just like this iPhone photo (they're just linear so you can adjust white balance and recover shadows, working with them the way you could a real raw file) or 2. They look like total garbage, noisy as heck and horribly soft, because the sensors are tiny and the lenses are simultaneously limited by diff…

They just need to offer an option without aggressive processing, they don't need to try to make it competitive with dedicated cameras.

Re: iPhone camera app replaces person’s head with a leaf in photo

#405

Post by ClumsyPilot »

pishpash wrote: post #342
ClumsyPilot wrote: post #291

Earlier quoted context omitted.

> This face, is it real? The distance, is it repositionned? Deepfakes, robocalls and Caller ID and voice impersonation, automatic ML in photos, if this train keeps going, we won't know what's real at all. I am struggling to see how we will function.

You will need a transcript of processing and intermediate results.

But how do you know a particular transcript is not fake?

Re: iPhone camera app replaces person’s head with a leaf in photo

#406

Post by Zak »

trompetenaccoun wrote: post #351
TedShiller wrote: post #276

Earlier quoted context omitted.

No free lunch is right. iPhone photos look incredible on iPhone screens. They look terrible on my high resolution desktop screen. Instagram kids don't know this, but that's ok, because we don't need them to, and neither do they.

Increasingly these photo"graphs" have nothing to do with reality either. I may be part of a weird minority but when I take pictures I do it to document things, I don't want them to be all fake and wrong. Some Chinese manufacturers have taken this to a ridiculous extreme, they make normal friendly faces look outright scary. Pictures shouldn't be edited by default, the user should be given the option if they want to. A…

> Pictures shouldn't be edited by default

This statement requires more precision. A camera sensor usually has more dynamic range than the display can represent. Lenses often introduce distortions. Sensors capture noise. The tint and color temperature of light sources vary greatly. Here's a set of seven images taken at steps along the path starting from as close as a JPEG can represent to the raw sensor data to a finished image that reasonably represents how my eyes saw the scene:

https://imgur.com/a/4paCKaL

When using a dedicated camera and generating a JPEG in the camera, a similar set of steps is applied automatically. There's no such thing as "no filter" in digital photography; even the "unprocessed RAW" is one program's opinion of how 12 bits per channel should be rendered at 8 bits per channel to display on your screen (as well as downsampled and compressed, in this case). There are often user-selectable profiles that each have a bit of a different look, much as different film stocks produce different looks (Fuji cameras actually call their profiles "film simulations" and name them after the company's film stocks).

So I think what you really mean is that you want the camera to produce an image that appears on a screen as much like what you saw with your eyes as it can.

Re: iPhone camera app replaces person’s head with a leaf in photo

#407

Post by kcb »

jiggawatts wrote: post #307
jjeaff wrote: post #302

Earlier quoted context omitted.

You aren't really comparing apples to apples here. Android is an open source operating system used by dozens of different hardware vendors. Crapware is only installed by some vendors. And iphone rarely has the best displays. They usually trade places with a few other Android vendors for best camera. As for security, iphone usually is the best. But it varies with different Android vendors in how well or how poorly the…

The iPhone 13 literally has the best display currently available, and more importantly, it's colour managed correctly. It is manufactured by Samsung, and they use the same panel in their own flagship phone, but they don't colour-manage as well or as consistently, making the iPhone the overall winner in my book. Other Android manufacturers have markedly worse displays in every metric. The fact that you don't appreciat…

My android phone has a folding screen that allows it to double as a tablet. Checkmate.

Re: iPhone camera app replaces person’s head with a leaf in photo

#409

Post by JKCalhoun »

radlad wrote: post #285
Gigachad wrote: post #264

Earlier quoted context omitted.

It never has been accurate. Even on dumb traditional cameras, colors are more of an interpretation than a reality.

I don't know about this - RAW files are recordings of sensor values. Those sensor values are accurate of what light the sensor measured. Then the sensor values are converted to a JPEG. So it's still an accurate rendition of the light - even though yes, it is a rendition of the light. But to completely replace some sensor values with some computer-generated values is a different ballgame, IMO. It's more akin to Photos…

There definitely though is some magic-sauce when de-Bayering [1] the RAW data and then playing games with color spaces and color profiles to end up with that final JPEG.

I agree with your point though. I dislike "computational photography".

[1] guess it is called demosaicing

https://en.wikipedia.org/wiki/Demosaicing

Re: iPhone camera app replaces person’s head with a leaf in photo

#410

Post by Auracle »

radlad wrote: post #285
Gigachad wrote: post #264

Earlier quoted context omitted.

It never has been accurate. Even on dumb traditional cameras, colors are more of an interpretation than a reality.

I don't know about this - RAW files are recordings of sensor values. Those sensor values are accurate of what light the sensor measured. Then the sensor values are converted to a JPEG. So it's still an accurate rendition of the light - even though yes, it is a rendition of the light. But to completely replace some sensor values with some computer-generated values is a different ballgame, IMO. It's more akin to Photos…

I agree with your point, but just to be clear for people:

When you bring that RAW photo into something like Lightroom or Capture One they’re automatically applying a base curve to the photo before you do anything.

In Capture One you can set that to “flat” which I believe is fairly unprocessed, and it takes a lot of work to get it to a usable state from there. They also have other options, and they recently changed their default setting and it’s pretty incredible how different it is from their old default.

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