High Dynamic Range (HDR)

Alright, so time for another photography post. I was recently introduced to a photography technique called HDR (High Dynamic Range). This is achieved using some software (although I guess there are other ways of doing it). This is most easily achieved using an SLR.

The Problem: You want to shoot some subject. In front of the subject is some foreground, behind it, some background. You point your camera at the subject, and it calculates the apeture size and exposure time for correct exposure. However, because you are shooting the background and foreground as well, these are often over/under exposed in the final image. Take this example, shot from my back yard:

Here the pool and grass are correctly exposed, but the foreground is under exposed, and the background (clouds) are over exposed.

The Solution: Obtain some form of HDR software (I used photomatic). Now shoot the same scene again, but shoot it once underexposed (by 2 stops or so, shorter exposure by 2 time stops), and one over exposed (by 2 stops or so, longer exposure by 2 time stops) all at constant aperture size (for constant depth of field - use the aperture priority mode on your camera). This can all be automatically done with a recent-ish SLR camera. Below are the under and over exposed photos.

Underexposed - the foreground is dark, but you can see the clouds better.

Overexposed - The clouds are not visible, but the foreground looks a bit better than the original.

You basically just push these into your HDR software, and there are some small amount of post processing options, and out comes the final product (below).

Voilà! This technique is useful in particular when shooting architecture, or landscapes when there is a lot of depth. It could also work when shooting a subject with a bright background.

Reverse Engineering "Black Snake"

Earlier this year I went on a tour of Birkinhead Breweries, a micro brewery near Hermanus in the Western Cape. One of their beers was called black snake, which was a delicate mixture of Klipdrift brandy, and milk stout beer, which came in at a jaw dropping 10% alcohol content. Needless to say, the student in me found this stuff quite pallet-able. Saturday being St. Paddy's day, I decided it would be a worthy Tribute to the Irish saint to try and make this stuff myself. I knew 2 things, the ingredients, and the final desired alcoholic content. The unknown was the exact ratio to mix the two constituents in. To the white board!

Using a complex set of equations, I discovered the ratio required to give me that magic 10%, namely 43ml brandy to 357ml Milk Stout (to give a 400ml total volume). These numbers were a little arbitrary, so I normalised up to the size of a single Castle Milk Stout quarts (750ml).

For this amount of beer, one requires 92 ml of brandy (I rounded up to 100 here - 4 shots of brandy per quarts, easy enough).

First step, pour the brandy into a 1L airtight (to prevent it going flat during the settling) container.

Next, pour the milk stout into the container. milk stout is especially foamy, so be careful here. A suggestion may be to add the beer first, giving you more volume for foam.

Close your vessel, and turn upside down once to mix.

After leaving it in the fridge for an hour to settle, and mix up nicely, pour into a beer glass and prepare yourself...

Enjoy!

What made it better was that I could enjoy this while watching the Sharks beat the Reds. This stuff was quite strong, and a bit of acquiring was required, but it started tasting better and better as I worked my way through it all. Some pretty potent stuff. Thanks St. Paddy. And Birkenhead. And Thanks to Monique for taking the photos.

The Moon

So after an extended break from blogging, and some pushing from my supervisor, I decided it was time for another post up in here. Earlier this year, Monique (whom I shall affectionately refer to as "the girlfriend") told me about a great deal one of her colleagues had for me. A whole SLR camera bundle, with 5 lenses, and a flash gun (external flash). The girlfriend, who is also an avid photographer (and who does a lot of it for the magazine she writes for) convinced me of the deal's worth, and that I would enjoy photography. Since then, I have learn't a thing or two about photography, and I decided it would make great subject matter for my blog. So today I bring you: The Moon.

A few nights before the last full moon, we got home late one night, and I saw this magnificent sight in the sky: A 3/4 full moon, in clear sky. I decided to try capture it, and this is the result.

It may be of interest to some exactly how I captured this level of detail. I was especially surprised to see the small craters near the day night line. To do this, all I did was hook my 300mm telephoto lens (which on my camera is equivalent to a 480mm), stuck the camera on to a tripod, and pointed it at the moon. I toyed with aperture and exposure settings until one worked. I settled on 1/15s and f/16. A smallish aperture exposed over some time gave me this. As a rule of thumb, a smaller aperture gives you a sharper image. Unfortunately, a bit of blur came in when I enlarged the image, due to a bit of camera shake which occurred when I pressed the button. Camera shake is emphasised at this level of zoom. I have some suggestions on how to make the next attempt better. However, the clouds rolled in a few second after I got this shot, and so I settled on this. I also cropped the photo, with the notable crater ~ midway along the day night line as a focus. Apparently, one's eye is drawn to one of 4 points on an image. I may try an experiment in future to see how true this is.

My idea for this blog is to post more photos in future, with maybe a small write up about how I took them. Photography is my new hobby and I am quite excited about it, and so I have been researching how to make mine better. So some of the details may be a bit technical, but I will also try to capture some kind of story in the posts too. I have a large backlog of cool images to put up here, and I will slowly work through them. Let me know in the comments if this sounds like a cool idea.