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Comment by ioedward | Hacker News Reader

I've been messing around with the Google Camera app and the new Camera API provided by Android 5. It turns out that you can actually obtain a lot higher quality images by using the DNG (digital negative) of the photo, instead of using the JPEG. By "HDRing" images yourself, you can actually outperform Google Camera's HDR+ functionality.

Here's the JPEG, non HDR+ shot on a Nexus 5: http://i.imgur.com/So44muL.jpg

Here's a similar image shot with HDR+: http://i.imgur.com/QFS3ZYd.jpg.

As you can see, the dynamic range is increased greatly; however there's strange black spots in the shadows.

Here's the same photo that I took in DNG format, edited in Lightroom:

http://i.imgur.com/VRFsnf5.jpg

And here's my HDR photo, combined 5 DNG exposures inside Photoshop HDR Pro's functionality:

http://i.imgur.com/RTT6ULz.jpg

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Yes, raw files have quite the dynamic range and the current generation of raw processors can really pull a lot of detail out of the shadows and highlights.

The strange black dots you find in the shadows are noise. Simple no data to produce any results.

The key part to in camera HDR is, automatic. No manually fixing your camera to tripod, copying them onto computer and the loading into software capable of HDR and finally manually processing them.

Wow thats quite interesting, i think ill try that this weekend, see if i can setup an automated solution too if i can get it working smoothly.

I didn't know it was possible to save real DNGs on Android (as opposed to JPEGs inside DNGs). I've been waiting for years to be able to shoot RAW on a phone camera.

Do you mind posting a DNG file of this photo? I might switch from iOS if Apple doesn't provide this functionality soon enough.

Sure! I would _not_ advise getting the Nexus 5. As noted below in other comments, the image quality and autofocusing speed has much to be desired. The Camera2 API that supports DNG is only available on Android 5.0 phones.

http://edward.io/raw_nexus_5.zip

In other words get a Nexus 6, or wait a phone that will get Android 5/Lollipop in the next few months and has a great camera sensor already (Xperia Z3/Z3 Compact, Galaxy Note 4) - or wait for Xperia Z4, Galaxy S6 or HTC M9 in spring.

Could Google's HDR+ also use DNG instead of jpeg and combine those automatically? That would make it much slower, though, so they'd have to take 3 at most.

There's nothing technical that's stopping them from doing it. I expect third party apps to do something similar once Lollipop has a higher market share.

HDR+ does the processing immediately after taking the images. I would hope that the "HDR" step happens before any compression.

Is this handheld or mounted somehow? That last image looks great, but I thought HDR Pro needed it to be stable between shots.

All hand held, shot from 1/35th of a second to 1/1000th of a second. HDR Pro does some basic auto aligning and ghost removal, AFAIK.

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