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Home » Cell Phones, Featured

iPhone 4S HDR Performance

Submitted by on November 8, 2011 – 5:31 pm 7 Comments

HDR – High Dynamic Range – photography is a method of achieving a degree of visual detail in highlights and shadows beyond what the camera’s image sensor can record in a single exposure. The HDR processing usually involves combining two or more frames taken at different exposures. This is done on the computer or inside the camera itself. Human vision uses the HDR approach. The dynamic range of your eye is relatively low. Speaking in photographic terms, the visual cortex part of your brain continuously processes multiple frames takes at different exposures to paint a highly-detailed image. The optics of your eye is comparable to a cheap plastic camera. What makes all the difference is the power of your brain.

The iPhone and iPhone 4S can’t compare to a human brain, but do offer a limited automatic HDR mode. The phone takes two photos in a quick succession at slightly different exposures and combines them into a single image that offers greater detail in both highlights and shadows. There are two primary drawbacks of any HDR system. First problem is that combining the photos into one takes time and processing power. The iPhone 4 takes nearly three times as long to make an HDR photo when compared to a standard non-HDR shot. The second problem is the ghosting effect: a brief period of time elapses between the two photos used for the HDR image and during this time the scenery may change slightly. This introduces the ghosting effect, which is exacerbated by low-light conditions, scenery movement and camera shake. iPhone 4’s HDR feature works best with plenty of light, stationary scenery and steady hands.

Below are a few examples of HDR photos taken with an iPhone 4S using built-in HDR functionality, as well as a couple of popular HDR apps. For reference we also included a couple of photos of the same scenery created using a Canon G10 and computer HDR-processing software.


A tripod-mounted iPhone 4S and a tripod-mounted Canon G10. The still-life scenery featuring wide range of highlights, shadows and reflections. Post-processed in Photoshop by a professional photographer to achieve the best quality for each image.

iPhone 4S

Below: non-HDR photo


Below: using built-in HDR feature of the iPhone

Below: an HDR shot using the Pro HDR app in automatic mode with two exposires

Below: an HDR shot using True HDR app in automatic mode with three exposures


Canon G10

Below: non-HDR photo

Below: HDR photo using three exposures at 0+/- 1/2

Instead of a conclusion

In my view, the best HDR result for the iPhone was achieved by True HDR app in this case. The Pro HDR app overexposed the final image. The built-in iPhone HDR logic underexposed it. The best photo overall is the Canon G10 non-HDR shot. But, of course, we are not comparing a cell phone to a high-end portable camera.

HDR is an interesting and useful feature that can produce excellent results under certain conditions. The main problem with iPhone’s HDR is ghosting. The phone’s processing power is insufficient to eliminate the ghosting effect in a reasonable amount of time. And the small and slippery form of the phone ensures there is plenty of camera shake when you take photos.


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  • Mark Neal says:

    Hi Igor.
    Nice review. I agree with your conclusion. I’ve also just done a review of the iPhone HDR (12/14/11)and found that it has limited range when compared to other technology. But your reference to the Canon G10 non-HDR shot image as the best photo overall seems odd. Though the background and foreground tones are very well balanced, the blowout on the fruit and glass bowl is pretty extreme. Just sayin’ :)

    • Igor says:

      I think iPhone’s HDR logic is geared more toward improving detail in highlights, rather than in shadows. This probably makes sense for portrait photography, where eliminating blowouts is a higher priority. Indeed, in a portrait, not seeing reflections on my sweaty face is more important than be able to tell that my black shirt has dark gray pinstripes. And as far as eliminating glare on the yellow pear, iPhone built-in HDR probably did better job than anything else in this review.

  • Roflcopter says:

    Im working on an HDR portfolio but wanted to know what the situation is with different format’s and the role they play.

    I have read that you can create a full HDR image with just a single RAW format image and i also use Photomatix to create my images and different formats provide different blending options such as a RAW image compared to a TIFF image.

    Can someone just break it all down for me thanks.

  • joevsyou says:

    I have a point and shoot camera and was wondering if i could take HDR photos on it. If its possible, how do i take an underexposed and an overexposed picture on a digital camera?

  • Samuro says:

    I recently obtained a Canon AE-1 camera. I have been interested in HDR imaging, and would like to try it out. I understand that HDR imaging requires editing in a photo editing program (I use GIMP), but I need help taking stock images. All of the tutorials I’ve come across are for digital cameras, so I need help with what settings (shutter speed, aperture, etc.) to use with this camera. Thanks for your help ahead of time.

  • stealspartansbcglobalnet says:

    Do you have to jailbreak an iPod touch 4G to enable HDR? If so, is there any alternative?

  • SteveO says:

    I have been using Photomatix to do so. But i don’t find the the results of this tool to be very much effective. Photomatix wont give me good results for images shot @ night or ones with low exposure.

    Is there any other tool you would suggest which can help & generate a single shot HDR (like a portrait) as well as a mult shot raw image HDR?

    Thanks for your answers!

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