I really struggled with this one. I have a lot of gear: cameras, lenses, bags, filters, etc. I use it all pretty regularly, and it has all been influential on my photography in some way. However, when it comes down to it, I think the thing that has been most influential is Adobe Lightroom 4. I'm sure many will agree, just as I am sure that many will think I'm crazy.
What is Lightroom?
Lightroom 4 is the latest version of Adobe's workflow application for photographers. Developed as a way to provide for logical, effective, and efficient workflow for ingesting and processing a lot of images. I really fell in love with Lightroom in version 3, but quickly made the upgrade to 4 after I saw what the new version was capable of.
I've been taking lots of photos since 2004. That year I took a trip to Alaska and brought home over 1000 images. Unfortunately, it wasn't until 2010 that I actually started to do anything with my images. Until that point, they would get copied to a folder on a hard drive and backed up on disk. Every once in awhile I would process a few images in Photoshop, but by and large I would take images and just stash them away. There were thousands of images and at hundreds of duplicates just clogging drives. It was a nightmare.
In 2010, I got Lightroom and started consolidating and organizing my image library. At first I didn't really understand what all the fuss was about, but it didn't take long before I realized just how easy it was to wade through huge collections of images. Once I had my house in order, so to speak, I imported and applied copyright data to the first of many cards from a recent trip; it took three clicks.
For the next 2 years, I didn't use lightroom for much more than managing my library--I would still go to Photoshop for any edits. Then, I saw some reviews of the newest version of Lightroom on Youtube and I had my mind blown with the editing capabilities in Lightroom. I was particularly taken with how well things worked in the new version so I upgraded. Since then, all those 12,000 pictures spanning the last 8 years have seen new life. I went back and started from the beginning--I edited my photos from Alaska and really made something out of quite a few of them
Examples of Use
1. Rapid ingestion of images from cards
2. Tagging images with copyright information and other metadata
3. Quick basic and advanced edits, like cropping or changing specific areas of a photo
To summarize, Lightroom (and Lightroom 4 in particular) breathed new life into my photography by helping me sort out my old images, keep my new images organized, and quickly perform most edits. If it weren't for Lightroom, I'd probably still be stuck in a rut with a disorganized mess of wasted photos.