Lightroom for iPad

Using an iPad as a replacement for Lightroom/RAW file manipulation is currently infeasible, for several reasons:

• the iPad hardware is limited and costly: at this processor speed, you could consider retouching one image, not hundreds; the top-level iPad has only 64GB of space, not expandable, shared between apps, data, music... you can buy 4 high-speed 16GB memory cards for a fraction of the cost.
• the iPad screen is nice and has brilliant colors, but it's not really the same as a good monitor; if you retouch on the iPad, the results are non-portable.
• RAW manipulation software for iPad is seriously overpriced (which is also the main motivation for this mini review); a typical app costs 0.99$, a RAW photo manipulation app costs 9.99$, and you may want to read carefully the description before you buy, because any feature which is not advertised is probably just not there.

What you really can do on the iPad is...

1. inspect images with high zoom, ideally at 100%
2. classify images, apply keywords, stars, labels, etc. and generate an xmp file

There's an app that does this quite nicely, called Photosmith

It's not cheap, but it works fine. The workflow is like:

• you need the Apple Camera Connector Kit, which contains two connectors: one is a SD card reader, the second has a standard USB port, that allows to connect any camera directly to the iPad
• in either case, the iPad can import jpeg and RAW images (apparently it supports the same RAW formats as MacOSX), so you can pick individual images and copy/move them to the photo library.
• when you start PhotoSmith (whose interface is very similar to Lightroom), it will see that there are new pictures and show them in its library (so no copy is made)
• at this point you can create a new collection and drag the photos in it, then you can start classifying

Not all RAW files are supported equally well: Sony ARW have a limitation on the maximum possible zoom, so you can enlarge a photo only up to a maximum width (say, 1920 pixels), which is large enough to check the picture quality, but it's just 40% of the original.

The app comes with a free plugin for Lightroom (both Mac and Win) that automatically downloads from PhotoSmith into Lightroom (not the other way) over wi-fi, so it takes some time.

Lightroom-style retouching can be done in another app called Luminance:

This app does non-destructive photo-editing, so the edited files consumes no extra space, until you (say) export a copy as a jpeg into the iPad camera roll.


There are other RAW manipulation apps, namely PiRAWnha (which I don't own, but you can see the user comments on the iTunes Store) and PhotoRAW.
The latter is the only one having a free lite version. It is advertised as having a very good RAW rendering engine, which in theory has no big limitation, however it's practically useless.
Its intended workflow is:

1. Open a RAW image, either saving it in the app folder via iTunes, or opening it directly from the iPad photo library (Connector Kit, mail attachment, browser download, etc.)
2. The software does a copy of the picture in an internal format (which the user cannot access anyway), and, very slowly, it displays the image in its own photo library.
3. After the pre-rendering phase, you have some retouch capabilities (admittedly, very fast) and an export function

This app will take literally hours just to import a reasonable number of images and pre-render them, consuming lots of memory. Furthermore, you will need an insane amount of free space to store both the "opaque internal format" and keep around the original RAW files (and more, if you want to export some retouched jpegs, which - according to the PhotoRaw website - may be pretty large).
In addition, the app shows very large thumbnails... of the wrong images: it always uses the original files, so the thumbnails don't reflect the current retouching status.

The only use I could find for the app is showcase a very small number of photos at very high resolution: I query Lightroom for photos rated 5 stars and that have no retouch, and I pick the best 10.