Friday, 30 July 2010

Lens coverage

I often get friends asking me what type of lens to buy after they have bought a new shiny digital SLR. A lot of them have switched over from an old analogue model to a new digital body.

A friend asked me last week to recommend a lens for her. She found that the wideangle lens which came bundled with her EOS 550d wasn't wide enough.

"Would you recommend that I get myself a 24mm?" she asked

I knew then that she had probably previously owned an analogue SLR.

"A 24 mm lens on your camera would be equivalent to a 38mm on your old SLR" I told her.

"How is that?" she asked.

Well to cut a long story short. I explained to her about the coverage provided by the APS-c sensor in her camera compared to the sensor in my camera (an EOS 5d)

"Your camera's sensor magnifies the centre part of the picture by 1.6, where as mine uses all of the picture."

I showed her this little chart that I put together. The pictures were taken one after the other using the same lenses my EOS 5d and my new 7d. The figures in brackets refer to the magnification factor from the 7d, so for example, the 300mm on a 7d body is "equivalent" to a 480mm lens on my 5d.


This simple chart explains more than reading about it on the 'net.

She is now looking for a 16mm Sigma lens which will be equivalent to a 25mm wideangle.

When I bought my first digital EOS (a 20d), the widest lens in my arsenal was a 24mm. For someone doing architecture, this was useless, giving the coverage equal to a 38mm. I forked out for a 20mm but this was also too limiting, being equal to a 32mm. So I sold that lens and bought the very lovely Canon EF 17 - 40L. I also bought a full frame body to be able to use it effectively as the widest setting was only like using a 27mm!

This means that my lens collection now goes from a 16mm to a 300mm, but when I use both bodies, taking into account, the magnification factor, the focal length of the longest lens is increased to 480mm

I've written a little bit more about it on my website and you'll find the exact page here.

Well. It's now nearly the weekend. Time to charge up your batteries and take some photos. As usual I welcome your comments and emails.

Have yourselves a great weekend.

Tuesday, 27 July 2010

Planning for the Streetparade

We have one of the largest "Love Parade" type festivals in the World, held every August in Zürich.

Upwards of 1 000 000 people come and enjoy the atmosphere.

Zürich main station becomes a party hall


The nineteenth Streetparade will be held on August 14th 2010 and I'll be there.

It's only a short route, 2.4 kilometers long but such is the mass of people attending that the Lovemobiles take several hours to complete it.

The organisers say (about the route):

"The unique Spirit of Street Parade also includes, of course, the stunningly beautiful route around Lake Zurich and the fantastic view of the lake and the mountains....

...a demonstration that calls on everyone to live in peace and tolerance with each other. A demonstration that is open to everyone who would like to enter into the Spirit of Street Parade, dancing to electronic music
."


I love this type of photography. Everything is constantly changing, wild vibrant colours, pretty girls, hunky men, bewildered old people etc.

The only thing that doesn't appeal to me is the music. A constant thump thump thump of bass that penetrates your whole body. Luckily, the organisers give out free ear plugs throughout the route. (they also give out free condoms, suncream and other "goodies")

 Security was pretty lax this year

I've been attending almost every year since 2000 but I'm a bit of a "fair-weather" photographer when it comes to the SP. If it is raining I simply won't go because sunshine, blue skies and the SP belong together. I just can't work up the enthusiasm to photograph the dancers in soggy costumes.

I'm hoping also this year to actually join the revellers on one of the Lovemobiles. I've already written a few emails and am waiting for an answer.

If I don't manage to get on a Lovemobile then shall have to plan my photographic experience carefully.

As I mentioned earlier, there can be around 1 000 000 people attending the parade. This can make navigating through the crowd, a bit difficult especially when lugging a camera bag. Plus, when things get tight, you are never sure if someone is dipping into your bag to help themselves. For this type of job, I'll be wearing my Agfa photovest. I won it a couple of years back in a photo competition and love it. It has lots of pockets, is splash proof (did I mention the water pistols that many of the youngsters carry?) but above all is comfortable because it distributes the weight of your gear across your upper torso.

 Me in my parade wear

I'll be shooting with my EOS 7d which will have the 28 - 135mm Canon zoom attached. As this is a small sensor camera, the equivalent focal length will be 44 - 216mm. I'll couple this with my EOS 5d and the 17 - 40 canon zoom. That way, I'll have all focal lengths from 17 - 216 covered. A Speedlite (set to minus 1 stop) will be sitting on top of the 5d. I use this to soften any harsh shadows from the sun.


Those two cameras will be over my shoulder and around my neck. In the pockets of the photojacket, I'll have spare batteries, memory cards, water, a snack or two, notepad and pen, business cards, suncream,earplugs, plastic bags (if it rains then I'll cover the cameras), mobile phone, wallet, a micofaser cloth to wipe the cameras if they get wet, and a longer lens. Probably my 70-200 as this will give me a 320mm equivalent (at the long end) on my 7d.






If you'd like to see a selection of my pics from previous years then point your mouse here.



More pics will follow..... weather permitting :o)

Monday, 26 July 2010

Sensor cleaning. My method.

The sensor on your digital SLR is a very delicate object and can very easily be scratched.

It is however a dust magnet and these artefacts will, after repeated use and changing of lenses, show up on your images.

The major manufacturers normally recommend sending the body in for a clean from time to time.

I have however, been cleaning my sensor myself for a long time,  without resorting to buying products like the Arctic Butterfly and their ilk.

Here’s what I do. Please note. This is not for the faint-hearted or for those of you with unsteady hands.

I use compressed air in a can. It must have the long drinking straw like extension on it.First make sure that your camera has a well charged battery or is running on mains electricity. This is because holding the mirror in your camera in a raised position puts a drain on the battery. My cameras tell me if there is enough charge to carry out the task.

Hold the camera securely and with the lens throat facing down. This is because I want the dust to fall out and not be redistributed inside.

Then I remove the lens and activate the “sensor cleaning” setting. The mirror flips up and the sensor is exposed.

Taking my canned air in one hand I first blow out a second or two of gas. I do this because the first attempt always blows out liquid and this can damage the sensor.

When I can’t see any more liquid coming out, I slowly move the “straw” inside the lens throat whilst keeping a steady pressure (gently) on the air can trigger.

This next bit is important. The can must then be kept steady. Don’t move it around or shake it because this can cause the expulsion of liquid gas. Instead, move the camera body around whilst facing down. Sounds difficult whilst reading this but is actually in practice, quite easy.

Move only the camera and not the air can


When finished, remove the straw from the lens throat and deactivate your camera’s mirror up mode (I do this on my EOS 5 by powering off the camera).

That’s it. One clean sensor. I must say however, that this method is only good for light dust and hairs. It won’t (always) get rid of anything physically stuck to the sensor. For the times when I have something that won’t budge with my air can method, I use a Sensorklear device from Lenspen which I bought from 7dayshop. This is recommended for 50 uses and cost me less than a tenner.

Here’s one pic of my sensor before the air can method.


... and here’s the image taken afterwards.




Well that’s it for now. Please feel free to email me or leave a comment. I really do value your opinions.

Till next time.

Monday, 19 July 2010

Another wall pic.

Monday, 5 July 2010

Saving the shadows and rescuing the highlights.

A couple of months ago, I was driving along a road, when I saw a castle through some bushes. I didn't have time to stop so I made a "way-point" reminder on my car's GPS device and carried on home.

Later, I bought my GPS upstairs and looked through the way-point reminders I'd made and saw that the castle was situated in a town called Zwingen (  47°26'15.48"N  7°31'37.16"E  ). Some 48 kilometers from where I live.

As it was a beautiful day, I decided to take a ride there to make some images for Google Earth. I enjoy doing the Google Earth stuff as it gives me an incentive to get out the house, explore the area and take some pics.

I got there shortly after midday which was a mistake as the sun was behind everything that I wanted to capture.

Normally (if doing this job commercially), I'd have come back later when the sun was in a better place. However, as this was just for fun, I decided to go ahead and document it anyway.

When I got home after the shoot, I was pleased with about 80% of the images but lots of them were suffering due to the high contrast range from the strong sunlight. This meant that there were either very strong shadows or burnt out highlights. Burnt out highlights are usually not saveable. For this reason, I tended to underexpose the images where I saw this happening on the monitor histogram of my 5d.

I ran the images where there were shadow details, through my HDR programme, HDR or High Dynamic Range photography lets you combine three successive images together so that the details in one of the images which you have purposely overexposed, is sandwiched over one which is underexposed. This means that the details in the highlights from the underexposed pic are visible as are the details in the shadows from the overexposed pic. All pictures should ideally be taken in quick succession and preferably on a tripod (to prevent ghosting).

Although I only took one image of each subject, I was able to use a special feature of my particular programme (Dynamic Photo-HDR.) whereby one image is processed as a "fake HDR". it's best to use RAW for this as there is plenty of detail for the programme to use. Perhaps the best example of its use can be seen on this image of a crucifix. Standing in the shade, it is hard to see any details in the shadows but the HDR process has done a magnificent job of bringing them out.

Untreated image from the camera compared with the HDR version

In the second two images, look how the process has bought out the details in the sky and especially in the leaves of the trees in front of the building.






There are plenty of HDR programmes available including freeware versions. I'm using Dynamic Photo-HDR  download a trial copy and see which works best for you.



See you later.