Aaron Bieber explains neutral density filters: what they are, how they work, and why one might want to use them. Clear and excellent.

Vowl is a free Macintosh application from stevenf (Panic) that given a tag or list of tags will display a random flickr slideshow in a window on your computer. Simple, clean, well designed and fun.

If you click on an image you go directly to that image on flickr.

If this becomes popular it will hopefully push people on flickr to use tags more effectively. Most flickr users have little idea of the power of tags, both within the flickr universe and with apps like Vowl, outside it.

Developed by Ansel Adams and Fred Archer in 1941, the zone system is a systematic way work with exposure and processing to get the right gradient of tones from white to black.

Most of us are just trying to get a handle on the different light meters in our DSLRs, let alone using them more proactively to create a range of tones but in face, getting a handle on the light meter is exactly what Ansel Adams was thinking about when he came up with this.

Maybe the best way to think about this is in its historical context and when Adams and Archer were working on this there were no film or digital cameras that had a mode dial with “automatic” on it.

This will be interesting.

Useful iPhone apps for calculating depth of field for a given focal length and aperture.

[via Edward McKeown]

I think it’s fascinating that the camera in the iPhone is the most popular (used) camera on flickr. I do think it would be fun to use this app for taking pictures on hikes and uploading them on the hike. Might have to try that.

Flickr app at iTunes Store (free)

[via Jon Moss]

All photographers, beginning to advanced should read this. Roger is a clear thinker, good explainer and a terrific writer.

[via Leandro Karunungan]

Actually, aside from a stupid multi-page web presentation, the tips are quite useful. Basic but good, basic information here.

[via Leandro Karunungan]

A well written review by Raoul Gatepin including video of three web based photo book services. His conclusion is they all have enough weaknesses so that none is the overall winner.

[via Lens Culture]

jeff.stiefer has posted a useful comparison of what the Canon 100mm f/2.8 macro lens will do at different apertures.