RobGalbraith.com
Go to advertiser website.
     Home
     RSS
     CF/SD/XQD
     About
     Contact
Go
Go to advertiser website.
 
Feature: impressions of the Apple iPad 2
Wednesday, May 4, 2011 | by Rob Galbraith
Are you considering an upgrade from an iPad or pondering whether it's time to buy your first Apple tablet? We've put together some observations about the iPad 2, including performance comparisons with the original iPad and commentary on the growing but constrained role Apple's newest iOS device plays in professional photography.

Shiny and New: The Apple iPad 2 with Apple Smart Cover attached and running Photosmith. Click to enlarge (Photo by Rob Galbraith/Little Guy Media)

If you've been reading this site for awhile then you've surely noticed how smitten we are with the original iPad. Not for image editing, since it's a bit slow for that and the apps need to improve, though it can be done. Not for RAW processing either, since it's way too slow for that and the available apps are mediocre. And not for a whole lot of other photography workflow tasks that are more efficiently and effectively accomplished on a laptop computer.

But for wireless photography on location with apps like ShutterSnitch or onOne Software's DSLR Camera Remote HD, photo management and Adobe Photoshop Lightroom syncing with Photosmith, prospective client presentations with Portfolio or Mediapad Pro and a myriad of secondary tasks like checking sunrise/sunset position in LightTrac or completing model releases with Easy Release, the iPad really shines.

For these jobs, the iPad matches or exceeds the abilities of a laptop, thanks to its combination of size, quick deployment, superb screen, long battery life and, most importantly, the quality of the apps.

Used strategically, the iPad is a fantastically useful photographer's tool. Which begs the question: is the thinner, lighter, video camera-equipped iPad 2 better than its predecessor at things that a still photographer might do with it? Does its dual-core A5 processor, 512MB of RAM and beefier graphics make it appreciably quicker at tasks like full resolution zooming or image editing than the original iPad and its single-core A4 processor and 256MB of RAM? And, has Apple done anything to improve (or degrade) the display? These questions are addressed on this page and the next.

Screen

The 9.7-inch, 1024 x 768-pixel touchscreen display in the original iPad delivers the best colour fidelity of any portable computing device we've ever tested. Better than the current stable of MacBook Pros, better than the MacBook Air 11 inch (we've not tried out the Air 13 inch) and better than several Dell, Lenovo and Toshiba laptops we've profiled in the past few months too.

Because the iPad lacks true colour managed viewing, its best colour accuracy comes only when displaying photos in the sRGB colour space. That limitation aside, it really does kick sand in the screen of every laptop we've had the opportunity to evaluate. The only way we've seen to beat the colour accuracy of last year's iPad, not to mention its wide usable viewing angle, is to pit it against a decent desktop monitor.

Yes, the original iPad's display is that impressive. The good news is the iPad 2's same-size, same-resolution display, while not the same component as its predecessor, features the same superb colour accuracy for a portable device. That said, its colour temperature, at about 7000K, is higher than the original iPad and makes for whites and grays that are slightly too blue. This, however, is a minor point. The iPad 2 display's colour accuracy is sweet for a device of this type.

ipad_1_kelvin.jpg
ipad_2_kelvin.jpg
RGB: Colour temperature of the original iPad's display, left, and the iPad 2, right

The iPad 2's display also surpasses the original iPad in one area: odd angle viewing. Dark colours take on a strong purple tint if you look at the iPad screen not from the side but in from one of the four corners. This trait is almost completely eliminated in the iPad 2.

The photos below show the difference. On the left in both is the iPad 2, and whether viewed straight on (top photo) or in from a corner at a steep angle (bottom photo), there's very little colour shift introduced into the black and white picture on the screen.

The original iPad, which is on the right in both photos, holds its own straight on, as it mostly does too when viewed from the side, up, or down. Only a touch of purple creeps in. As the bottom photo reveals, however, if you look at the screen on the diagonal it mutates into a purple mess.


Same But Different: The iPad 2, left, and original iPad, right. Click photos to enlarge (Photos by Rob Galbraith/Little Guy Media)

The real world ramifications of the original iPad's purple problem are minimal, unless you make a habit of watching the screen from odd angles. But, it's to Apple's credit they made this quirk go away almost completely in the iPad 2.

Import, wireless, USB and app performance

Double the RAM and double the processing cores in the iPad 2 should translate to quicker still photo processing times, and it does. As you'll also notice, however, 802.11n Wi-Fi speed is effectively identical (which is not surprising, since teardowns reveal the same wireless component from Broadcom in both the original iPad and iPad 2) and therefore remains much slower than a Mac laptop. Also unchanged is dock connector throughput, which plays a role in photo import speed as well as the subsequent transfer of pictures from the device to your computer and into a program like Lightroom.

Photo import

The tables below list the time it took to import 75 Canon EOS-1D Mark IV RAW, JPEG, or RAW+JPEG pairs from a SanDisk Extreme Pro 32GB SDHC card to the iPad and iPad 2 using the Photos app.

For the first table, the card was inside the SD Card Reader, which is one of the two modules supplied with Apple's Camera Connection Kit. The "camera reader" in the second table was an EOS-1D Mark IV connected by USB cable to the Camera Connector module from the same kit.

import_sd_reader_table.jpg

import_mkiv_reader_table.jpg

The results might at first seem confusing, since they show quicker RAW+JPEG import times than they do for RAW alone. This is counterintuitive, since the RAW+JPEG pair represents double the number of individual files and more total data than RAW by itself. The reason for RAW+JPEG's mysterious speed advantage is explained by the fact the Photos app is both transferring the pictures from the memory card and generating previews for those pictures at the same time. The Photos app goes about doing so this way:
  • If it's importing a RAW file, the preview is created from the JPEG inside the RAW file
  • If it's importing a JPEG, the preview is created from the JPEG (obviously)
  • If it's importing a RAW+JPEG pair, the preview is created from the JPEG and that preview represents both halves of the pair
In this test, then, considerably more processing time is required for the Photos app to generate its 2048-pixel-wide preview from the 4896-pixel-wide JPEG inside the RAW file than it does from the 2448-pixel-wide Small JPEG that's part of the RAW+JPEG pair.

As a result, the total time to transfer and make previews for the 75 RAW+JPEG pairs is less than the 75 RAW files. Doing the import test this way reveals a few things:
  • A considerable chunk of the time spent importing a picture goes to generating a preview for that picture. The higher the resolution of the source file, the greater the amount of time the iPad or iPad 2 spends cranking out the preview.

  • The speed at which data travels from the memory card into an iPad 2 is very similar and perhaps identical to an original iPad. It's impossible to measure throughput exactly, since the file transfer and preview generation are shown to the user as a single step. Our best estimate is that card-to-device throughput peaks at about 14-15MB/s. This is true whether the SD Card Reader or Camera Connector module is hooked up.

  • The iPad 2's increased horsepower enables the Photos app to build previews at a much faster clip than the original iPad. This speedup is almost entirely responsible for the faster import times of the iPad 2.
Put another way, if it were possible to turn off preview generation during import, the original iPad and iPad 2 would show import times that are about the same. Because preview generation is always on, however, the iPad 2 is invariably going to complete an import faster. How much faster will be dictated by the resolution of the source file from which it creates the preview.

ShutterSnitch

In our estimation, this was the first killer professional photography app to emerge for Apple's tablet, and it remains the app we use most often. It also happens to cruise along very nicely on the original iPad; the current release of ShutterSnitch has relatively few performance pain points, even when running on last year's model.

That said, it can be slow to render higher-resolution files when zooming. Also, saving a big batch of pictures from ShutterSnitch to the Photos app can take approximately forever. Overall, ShutterSnitch and the original iPad do get along well, but these two tasks are prime examples of where the app can lag. And where the iPad 2 could, potentially, usher in a helpful speed boost.

The table below shows the time it took to perform the operations listed.

shuttersnitch_table.jpg

The numbers require lots of explanation.

The first test - downsampling 10 Nikon D3X JPEGs to Medium resolution, then attaching them to an email message - was already quick on the original iPad. At an average of less than two seconds per 24.39 million pixel photo, the iPad is out-and-out fast. The iPad 2 reduces the processing time slightly, to just over 1.5 seconds per D3X photo, and this is just enough of a difference that you'll notice it. But, it's hard to get excited about the moderate performance gain of the iPad 2 when the original iPad was already plenty speedy.

This particular test is representative of what it's like to use ShutterSnitch on the original iPad and then the iPad 2. On the iPad 2, almost every operation in ShutterSnitch feels like it has an extra spring in its step. The app is more responsive when swiping through pictures, scrolling through thumbnails, changing the sort order, opening menus, receiving and exporting simultaneously and other bread-and-butter tasks. Problem is, ShutterSnitch on the original iPad was already responsive enough at these things, as well as quite stable even when juggling collections filled with thousands of camera JPEGs.

Which brings us to saving to the Photos app, which is faster but still so slow. It takes almost 15X longer to complete this operation on the iPad 2 than to make a copy of the same set of pictures on an SSD-equipped MacBook Pro 17 inch. The reason is the iOS' insistence on generating a preview for every picture destined for the Photos app and tying up ShutterSnitch as it does. It could make the preview in the background or even do it later, at the time the Photos app is opened. Instead, the iOS forces it to happen inline with the save operation.

So, saving a picture from ShutterSnitch to the Photos app involves both copying the picture internally and making a preview of it. While that's happening you, the user, waits. The iPad 2 (at least as of iOS 4.3.2) doesn't make it any more practical to save large collections of pictures from ShutterSnitch to the Photos app, unless you're prepared to have ShutterSnitch hand off to the Photos app a version of each picture that has been drastically reduced in resolution.

In apps that are capable of full resolution display, including Boinx LightLoupe, ShutterSnitch and Photosmith, zooming happens like this: a lower resolution version of the photo is magnified initially, then the portion of the picture that's visible on the screen is rendered at full resolution. The rendering happens in blocks, usually starting from near the centre of the screen.

The pixel count of the photo, and whether the device is the iPad or iPad 2, affects how quickly each block is rendered. In practice, once two blocks are rendered it's possible to start looking at the picture critically, checking for sharpness, focus error, noisiness, etc.

If you've not seen how this works then watch the video below. It shows the same Canon EOS 5D Mark II JPEG being zoomed on the iPad 2, left, and original iPad, right. The app doing the zooming is LightLoupe, but ShutterSnitch and Photosmith work the same way. We opted to use LightLoupe here because it's easier to see, in a web video, each block's transition from fuzzy to rendered.

As mentioned, ShutterSnitch and Photosmith tackle the photo block by block also, the only difference is LightLoupe's darkening of not-yet-rendered blocks, as well as how long each app takes to complete the rendering of all visible blocks. Photosmith is the fastest, followed closely by LightLoupe, and then ShutterSnitch.

Old and New: Full resolution zoom rendering in Boinx LightLoupe on the iPad 2, left, and original iPad, right (Video by Rob Galbraith/Little Guy Media)

The original iPad renders the first block almost as fast as the iPad 2. Soon after that, however, the iPad 2 steps on the gas, leaving the original iPad in its dust. LightLoupe, Photosmith and ShutterSnitch, they all show that the original iPad can almost keep up to the iPad 2 at the start of the zoom. The original iPad loses ground quickly after that, though.

Because image assessment can begin after only a couple of blocks have been rendered, the most meaningful zoom comparison is the two-block test. In ShutterSnitch, this test took 8.4s on the original iPad, and 6.8s on the iPad 2, which is a negligible real world difference. The iPad 2 feels a little faster, but that's all.

Not described in the table is the rate at which ShutterSnitch can receives pictures from a camera transmitter, Eye-Fi card or computer FTP client, or the rate at which pictures can be transferred from ShutterSnitch to, for instance, an FTP server on a local network. The answer is the original iPad and iPad 2 are the same.

When the router is an Apple Airport Extreme (current generation), pictures will flow into ShutterSnitch at up to about 3.6-3.8MB/s over a solid Wi-Fi link, with sustained transfer rates averaging out to somewhat less than this. The transmitter has to be capable of sending data at this rate as well. A modern 802.11n-equipped laptop will be, but the current crop of Canon WFT transmitters, Nikon's WT-4/WT-4a or an Eye-Fi X2 card, all peak at less than half the throughput that the iPad/iPad 2 can manage.

When the original iPad or iPad 2 is the transmitter, pictures transfer from ShutterSnitch to a local FTP server at up to about 2.3-2.4MB/s, with sustained rates often hovering in the 1.3-1.5MB/s range.

What does all this mean? It means ShutterSnitch generally runs well on the original iPad, and is generally a bit quicker on the iPad 2. But the speed bumps are either incremental or well short of what they would need to be to significantly alter the experience of using ShutterSnitch.

None of this is an indictment of ShutterSnitch, by the way. The fact it runs efficiently on the original iPad is a testament to the app's good overall design. If you've been eyeing an iPad expressly for ShutterSnitch, but cost has been holding you back, one option is to save some money by getting an original iPad  - new, refurbished and used units are readily available - rather than an iPad 2.

The only ShutterSnitch-related reason that might cause you to regret choosing the older iPad is the iPad 2's improved graphics architecture. ShutterSnitch could, in a future release, offer higher resolution external display support than it does now. If this happens, it would enable much crisper slideshows than are possible or will ever be possible with the original iPad.

Notice the "if" in the last sentence: while the iPad 2 has the hardware oomph to display pictures at up to 1920 x 1200 pixels on an external screen, ShutterSnitch developer Brian Gerfort hasn't yet committed to reworking the app for this, though he is investigating the possibility.

(Even without any underlying changes, ShutterSnitch's slideshow transitions are smoother on the iPad 2 when the show is being mirrored on both the device itself and on an external screen, so this is perhaps one other small advantage of the iPad 2.)

Otherwise, based on what we've seen of ShutterSnitch on the iPad 2 so far, it's hard to make a case for upgrading from the original iPad for this app alone.

Continued on the next page...
Next Page: Filterstorm, Photosmith, PiRAWnha and more
Go to Page: 1 2 
Send this page to: Twitter Twitter Facebook Facebook Google Bookmarks Google Bookmarks Email Email
Go to advertiser website.
2000-2013 Little Guy Media. Not to be reproduced without written permission.