With my current camera gear filling an entire carry-on bag, a laptop is too much extra bulk/weight, so on my last few trips I’ve been surviving on an ipod touch for limited web browsing, email access and so on. This got me wondering whether a tablet would be a good fit, especially if it gave me the ability to review, back-up and share photos on the move whilst also improving my internet experience and offering video/ebooks for when IFE doesn’t cut it. The launch of the latest ipad, with a screen resolution that puts even my desktop to shame, provided just the extra nudge I needed to explore the idea seriously.

But in researching my options I found myself immediately confronted by a stack of conflicting information regarding what was or wasn’t possible with the ipad. Presumably to encourage uptake of the higher-capacity models, apple don’t include a memory card slot, nor standard USB sockets, on the ipad. Instead there’s an external connection kit, and establishing which permutations of ipad model / iOS version / camera brand / connection type would co-operate was not easy – perhaps not helped by the lack of tech savvy from some users, as many comments on apple’s site strongly suggested PEBCAK. A visit to the store didn’t allow for a practical test as they didn’t have adaptors in stock, but they were willing to accept a return of the ipad if it proved not to be suitable for purpose. Probably knowing that I’d really struggle to give it back after playing for a while, even if some sort of android tablet would be more useful for my needs!

Well, mine arrived yesterday, and I’m pleased to report that for the Canon 550d (T2i) – and presumably their other sd card based models – it all plays together beautifully. But in trying it out, I stumbled into various other seas of online confusion regarding photo handling, so I thought I’d collect together what I’ve learnt so far (admittedly, in all of 24 hours) in the hopes it helps save others some time/effort. This is not a guide to taking photos with the ipad, which still strikes me as a ridiculous idea!

Photo transfer: from camera to ipad

Apple’s camera connection kit supplies two adaptors – one for SD cards, the other for USB. Both are in theory viable options for accessing content from a 550d, and indeed both work in practice; I prefer using the card reader rather than trying to cable the camera to the pad. But whichever method you use, the effect is the same: on connection, the ipad’s Photos app launches, and you can select to import either all images or specific shots. Post import, you have the option to delete the originals from the card or keep them. The sorting is rather basic: you get new albums called “Last Import” and “All Imported”, and under the events tab you get collections by date. So there’s no way to go through and group photos by trip, for instance.

However, despite the filing shortcomings, you do get the full 5148*3456 image, and RAW format is supported (if you shoot in RAW+JPEG, it imports both); so you get to take full advantage of that high-res screen. Even more surprising, it’ll import full-HD video too, as Canon provides footage in mp4, one of the few formats the ipad won’t turn its nose up at.

Alternative: from USB memory stick to ipad

You can also import in exactly the same way from a USB stick, provided you mimic the file structure of a camera card: there must be a folder called DCIM, in which all the files (again RAW and JPEG both work, as does suitable video) must reside (sub-folders might be ok, I haven’t investigated that). The process is identical to above, and you get the full-resolution images, so that’s a quick and easy way to import from a computer without the overhead (or resolution drop, see below) of going through itunes.

Photo transfer: from a computer via itunes

If you want to be able to showcase work that already resides on a computer, you can transfer it with itunes. This has the advantage of preserving directory structure: so instead of the date-sorted events, you can have thematic albums like Boston highlights 2012 or Mathematical Art or whatever. However, itunes (which is becoming an increasingly-clunky general file manager for idevices, rather than just handling music) has a fairly crude sync system: you can specify a root directory, then you either get everything within that (recursing all subdirectories) or can select a subset of its subdirectories – but no further. So, for instance, with my filing system of Pictures->life stage->home location->year->event name->subtheme it’s impossible for me to just pick out a few favoured subtheme folders without restricting to a single event; or to get one year from each of two locations. As a workaround, I’ve created a new folder called ipad selection which gets synced in its entirety, and I export desired content from picasa to subfolders of that; it means duplicating on the computer anything I want to have on the ipad, but desktop disk space is cheap!
A further niggle is that during the process, itunes drops the resolution of any file over 14.2MP; for the 550d’s 3-by-2 aspect ratio, this means you get an image of size 4608 by 3072 on the ipad post-sync.

Photo transfer: from ipad as a storage device to a computer

Being able to back up photos as full-res JPEG and/or RAW to the ipad is only really of use if you can retrieve them in that state – especially if you’ve been using it to filter out the bad shots or do some basic corrections with iphoto, so you’ll be wanting to start your desktop workflow from that stage, rather than the card contents (you are keeping the files on the cards too whilst away, right?). Fortunately, if you connect via USB to a computer, the ipad appears just as a USB mass storage device would, with a DCIM folder containing any images that were imported to it; on windows this’ll trigger the usual autoplay options to import with your photo manager of choice, or browse manually. Note that this doesn’t include files that were synced across from another machine via itunes, just the contents of the ‘all imports’ folder or images created/saved with apps.

Photo transfer: from ipad apps

With the photo app, you have options for email, message, tweet and print; you can also set an image as wallpaper or assign it to an address book contact. Other apps such as facebook can also access the photo library (both imports and synced content). iPhoto is another £2.50 (apple being annoyingly cheap and not including it out the box), but has a broader set of built-in sharing options: journal, the camera roll, itunes, email, beam, print, twitter, flickr and facebook. Plus you can do some basic editing first, and it offers information that the photo app really should, like image resolution and some exif data.

It’s also possible to sync a buffer of images between apple devices / computers using icloud, but since I only have the pad (and would rather import manually as if it were a mass storage device, rather than try to pull RAW files through my internet connection) I’ve not really looked into it.

Photo-viewing online

Here’s where things get quite a bit messier. Although the retina display is 2048 by 1536, if you attempt to view a photo that’s too large in safari – or, it seems, any other browser – it’ll first get downsized to (at most) 1024 by 768. This makes sense on iOS platforms that can’t display more than that anyway, but on the ipad3 it’s a terrible idea, as to fill the real 2048-wide screen with the virtual 1024-wide window, the image then has to be interpolated back up! So you only use a quarter of the available pixels to construct an image on a screen that could have handled all of them… This effect has been documented and illustrated (if you’re using an ipad) here, where the meaning of ‘too large’ has been precisely pinned down: PNG format files aren’t affected, and using progressive jpg may be a workaround, provided everything in your workflow, such as picasa or flickr, preserves that. I ran into it whilst using flickr’s all-sizes mode, when I noticed that my 1800 by 1200 images were coming out physically smaller – and uglier – than the 1024 by 683 versions flickr was generating. What this means in practice is that, for viewing a JPEG on an ipad3, you’re better off supplying a 1773 by 1182 image to flickr (or elsewhere) that will be used in its entirety, rather than a 1800 by 1200 image that’ll drop to 900 by 600 then get interpolated to fill the real 1800 pixel width. This seems like a glitch – it wouldn’t even save any download time, as the image is presumably grabbed then decimated – but until/unless apple fix it, it’s worth knowing. Especially if you’re trying to show off your fancy new toy’s capabilities!

Relatedly, websites that fit perfectly happy on a 1920 by 1080 display might not work as desired on mobile safari, even though it has a larger canvas to work with. Such as, erm, this site: my HD youtube embedd in the post below fits the central column when viewed from my desktop, but not the ipad. I assume its emulating a width of 1024 to avoid unreadably-small text, but there must be a better solution.

Summary

• You’ll almost certainly want to get iPhoto.
• Both parts of the camera connection kit work fine with a 550d.
• Importing from sd card, from camera by USB, or from an appropriately-structured USB device, will give you the full resolution and RAW files.
• Sync via itunes offers (basic) folder structure, but at the cost of a resolution drop.
• Viewing images online can lead to a substantial resolution drop, to the extent that images just under the threshold will look better than larger ones.