First Look At iOS 4.1 HDR on iPhone 4
This entire week I’ve been checking iTunes for the iOS 4.1 upgrade, and this morning it was finally available. The biggest thing iOS 4.1 brings is the LONG awaited bug fix for the iPhone 4’s proximity issue when you’re on a call – hopefully now I won’t be hanging up on people while I’m hold the handset to my face. But Apple also announced that iOS 4.1 would bring an interesting new feature – HDR for the camera. If you don’t know much about HDR and this new feature, check out my post on this topic from last week.
When you fire up the iOS 4.1 camera app, you see a new toggle button at 12:00 on your screen (next to the flash toggle) for HDR. There’s also a setting for HDR in the “Settings” app:
The only setting control you have available controls whether or not a “normal” version of the photo is saved, along with the HDR version. Based on what I’ve seen, I recommend this setting be set to “On” and that you always save both HDR and non-HDR versions of the photo. The pre-release information I read seemed to indicate that the phone would take three separate images and blend them into one optimally exposed photo, which is honest-to-goodness, no-foolin’ HDR. As a photographer, I was curious as to how the app would achieve this with a hand-held photo – without a way to keep the camera perfectly still, there will be some variations caused by motion in three separately taken exposures. Accordingly, if you combine these three separate photos, you’ll get an ugly looking photo with “ghosts” where the objects in the three images don’t precisely line up.
Here’s a couple of photos I took to test iOS 4.1’s new HDR feature. Be sure can click on the photos to see them in a larger, gallery view. I’ll first show the non-HDR version, then the HDR version so you can compare:
Here’s the second photo:
About the best thing I can say about Apple’s first attempt at implementing HDR on the iPhone is that they have a lot of room for improvement. Here’s my specific criticisms:
Exposure: The HDR versions simply look over-exposed, with blown out highlights. While iPhone 4 photos often look under-exposed and dark, the HDR versions go too far the other way.
Detail: Where’s the enhanced detail you get from HDR? To my eye, I’m not seeing any added detail on these photos.
Controls: It absolutely stinks that you have no settings or controls available to allow the user to configure things like saturation, contrast, etc.
I’m reasonably certain that this so-called HDR effect is not being handled through three separate exposures. But I’m not certain what the app is actually doing. It’s possible that the app is simply applying some tone mapping algorithms to the “normal” version of the photo. However, I think it’s more likely that the camera app is just fiddling with the exposure of the photograph, using the normal photo as some sort of a comparative baseline. And there’s a couple of different ways it could be doing this, but the short answer is that in my mind, this isn’t true HDR as advertised.
Depending on the kind of photo you’re taking, the iOS 4.1 may or may not help enhance your photo – which is why I recommend you keep the toggle for “Keep Normal Photo” set to “On.” In this specific test, I don’t think it’ helped.
For giggles, I applied my favorite iPhone image enhancement app PERFECTLY CLEAR to the first, normal photo:
To my mind, the PERFECTLY CLEAR version is much better – though still no substitute for a true HDR image, or at least one which has had some tone mapping applied to a single image. Let’s hope the Apple further enhances this feature in iOS 4.2.
John B. Holbrook, II
John B. Holbrook, II is a freelance writer, photographer, and author of ThruMyLens.org, as well as LuxuryTyme.com and TheSeamasterReferencePage.com. *All text and images contained in this web site are the original work of the author, John B. Holbrook, II and are copyright protected. Use of any of the information or images without the permission of the author is prohibited.