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Showing posts from December, 2015

First LA impressions

I'd actually been in LA very shortly before, but this time I'm with Ana, and I always notice more stuff when I have someone to comment it with (especially her).

I rented a car with Dollar from LAX. I show up at the place, they give me some paperwork and point me towards a row of compact cars. As I am walking towards them, I am trying to find the license plate in the paperwork and fail to do so. I ask which car I am supposed to take and the answer is: anyone I want from that particular section. This is genius. Every single time I rented a car in the past, they gave me the keys in the office and that was it. This way instead I can choose whichever model I want, from the class I paid for. In our case we wanted to have a large trunk, so we got a car that had one, but if we had preferred a more compact car, we could have had that too.Just to get around LA the GPS inevitably directs you to a bunch of roads that are famous from movies (often movie titles). Sunset Boulevard, Mulholland…

A consistent measurement system for photography

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Everybody who starts with photography must eventually come to grapple with f/numbers, shutter settings, focal lengths and ISO values. The problem with the current system is that they are all on different measurement systems. Focal length and ISO are linear, shutter speeds are expressed as fractions, and apertures are proportional to the square root of the amount of light.

The end result of these different scales is that the actual values are just about useless for any practical calculation a photographer might need to do.

For example let's say that you are wondering what ISO you will need to photograph a stationary object lit by streetlights, using a 28mm f/2.8 on a full frame DSLR. Street lighting is usually around 15 lux, which is about LV 2. LV 0 is defined as the amount of light that requires 1 second exposure at f/1 and ISO 100, and LV 2 is two stops brighter than that. Let's see, f/2.8 is - f/1,  f/1.4, f/2, f/2.8... Three stops darker than f/1.  Three minus two is one, …

Nikon AF-S NIKKOR 28-300mm f/3.5-5.6G ED VR Lens Review

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I just upgraded from a D90 to a D750, and I decided to buy a superzoom to use when I don't want to carry around the full bag of primes. It was a tossup between the 24-120 and the 28-300, but in the end I picked the latter since I already had a 24mm f/2.8D which had been collecting dust during my decade of using DX-sized sensors. In fact I might trade the 24mm with a 20mm if the opportunity comes along.

Anyway, there's a lot of controversy surrounding this lens, so I thought I would make some tests to decide whether to keep the lens or not, and since I have them, I figured I'd post them online.

So here they are. The first one are 200x200pixel crops (roughly) from the center of a resolution target. I took every marked focal length, and every full stop of aperture. I put a green dot next to the combinations that I considered satisfactory. For comparison, the "Optimal" square was obtained by taking a photo much larger version of the same pattern and scaling it down …