Photo App Review: Big Photo - Okay zoom but great resize for iPhone

Big Photo
Version reviewed: 1.2
Price: $0.99

Bottom Line: I like it. For a dollar, this app is well worth it to be able to resize images on your iDevice. Large file sizes make this app a bit cranky.

Here’s an undiscovered gem of a utility. With big claims in the App Store description and a few five-star user reviews — this app looked like a clunker and it was a very pleasant surprise to find that it is not and it worked as well as expected.

Big Photo lets you resample images up to 600% on your iPhone or iPad. Results are comparable to resizing images in Adobe Photoshop. If you’re an iPhoneography purist who wants to keep it all on the iPhone, this is an essential tool, but there are some caveats. Read on to find out why. >>>

Big Photo allows you to view pictures of any sizes with unlimited zoom in high quality. The app has a very smooth, precise crop tool with exact coordinates and pixel sizes.

But where I found Big Photo to be most useful is it’s image resampling tool. Big Photo lets you upsample or downsample pictures with exact pixel sizes with or without locking aspect ratio. It then automatically saves the enlarged or downsized pictures back to your Camera Roll.

You can resize an image by adjusting the slider up to 600% or all the way down to 10%. You can also enter in specific pixel dimensions. I was pleasantly surprised that Big Photo’s resizing images works as well as it does. Resampling is fairly quick on an iPhone 4S. Results are very, very smooth considering the app is essentially filling in gaps between pixels — guessing. It looks like Big Photo uses an algorithm similar to Photoshop’s Bilinear interpolation. It’s not as smooth as one of the more complex interpolation algorithms, but the results should be acceptable in nearly all cases. Typically in Photoshop, I would use Bicubic Smoother interpolation for upsampling, but see my comparison shots below. Zoomed in close, there’s a slight visible difference. For me, the difference is minimal and it’s not a dealbreaker.

The developer says the app will enlarge any image you throw at it. The app crashed for me often when I tried to resample an 8 MP image up to 600%. That’s a lot of data for my iPhone to be chewing and it would have surprised me if the app didn’t crash. In real world usage, you probably should use this app to upsample no more than 200% and still expect acceptable results. Testing the app by resampling to 300% I had fewer crashes, but it was still cranky.

There are very few apps available that upsample images. Filterstorm has a resampling tool but it’s limited to 22 megapixels or about 6000 pixels wide. If your device can handle it, Big Photo will go much larger.

Having the ability to toggle the aspect ratio lock while resizing is a good feature if you need it. It defaults to “on” which is where I’ll leave it. It can come in handy for removing horizontal or vertical distortion in an image.

For viewing large images, the zoom function is very slow and choppy. The two-finger pinch gestures zooms the screen out slowly in frustratingly small increments. You can touch a spot on the screen and the app will zoom into that area in a popup window (see screenshot above). This is much faster, but is probably a more useful feature on the larger screen of an iPad.

The crop tool is smooth, but lacks most of the features expected in a standard crop tool, such as fixed aspect ratios, presets, and straightening. It also automatically saves your image after every operation which can gobble up space quickly. The crop tool needs a lot of work. Right now, it’s the crop of last resort. There are much better crop tools available in other apps that I’d recommend using.

Big Photo’s real use for me is the image resampling. No other tool on the iPhone resamples and enlarges images this big as well. Real world uses for Big Photo are enlarging low resolution 612×612 Instagram-style photos to a usable size for prints. Big Photo is perfect for enlarging images for oversize output for posters or exhibition prints.

You should know that interpolated photos aren’t as sharp as shooting with a higher resolution camera, but sometimes enlarging an image is simply necessary. For this task, Big Photo creates good results. The larger and better your image is to start with, the better your results with this app are likely to be. Full-res iPhone 4S photos will enlarge great with little visible loss of detail. You should get good results even from the 3.2 MP full-size iPhone 3GS images. That said, you won’t get miraculously usable results by trying to do a 600% enlargement on a low res 612×612 px photo. If you stick to enlargements of no more than 200%, you’ll probably be pleased with the results.

For a buck, Big Photo is well worth it to be able to resize images on your iDevice. A half a star off for bugs, quirks, and instability. You have to coddle this app. Despite its current issues, Big Photo is a singularly useful app that has definitely earned a spot on one of my front screens. I like the app. I’d like it better if it didn’t crash often.

Big Photo is $0.99. It’s a Universal app that will work on both iPhone and iPad. Requirements: Compatible with iPhone, iPod touch, and iPad.Requires iOS 4.0 or later.