Thursday, 17 May 2012

Aperture flex-cable replacement

The Canon EF-S 17-85mm 1:4.0-5.6 IS USM is a great walk-around lens for the prosumer photographer. However it has problems with the flex-cable, that controls the aperture iris;
When the lens has been in use for a few years, usually after the warranty has run out, the camera will begin to display 'err 01' or 'err 99' periodically, usually when the lens is zoomed in and the aperture is at a lower value than f/4.

The Situation
I have a Canon EOS 60D and I really like the camera, with it I have a Canon EF-S 17-85mm USM, it is a great combination for most situations, it's not the best lens on the market, but you get a lot for your money.
Lately though, it has begun malfunctioning, especially when I photograph outside in good light.
If you use your camera a lot, you know how I feel about a periodic problem with the camera, if it fails to take a picture at just the wrong time, you might miss a great shot. This means that a camera that malfunctions sometimes, is as useless as one that never works.

Why fix it myself?
So I contact my local Canon-dealer and they tell me, that they can send the camera in for repairs. This will cost about 600 DKR (80€/60£) just to figure out what the problem is, then furthermore 600 DKR for every hour it takes to fix and on top of that the price of parts. I figured that this would cost a minimum of 1600 DKR (210€/160£) and started Googleing for a solution.

What's broken and why?
Small part, big problem
I Googled "Canon 17-85 err 01" and a few things came up, mostly posts about the flex-cable that controls the aperture-iris. Apparently Canon has made a bit of a mistake in their design of the lens, the cable consists of 8 tiny wires inside the flex-cable, 4 wires are thicker than the other 4 and the thin ones fail as zooming the lens bends the cable.
This flex-cable cost as little as £2 on eBay if you are not comfortable with soldering sensitive electronics, you can buy a fully assembled aperture for about £25 on eBay.

How to fix it?
After diagnosing the problem and ordering the part, I needed to find out how to take a camera lens apart, without breaking anything.
I found a video on the subject and after watching it a few times, I felt confident that I could accomplish the deconstruction and reassembly of the lens. 
When trying to repair something as complicated as a camera lens, it is very important to have the proper tools for the job, using a wrong screwdriver will ruin the screw-heads.

Tools for the job
  • Phillips Screwdriver #000
  • A pair of tweezers
  • A soldering iron 
Make sure that the tools are anti-magnetic, as the lens contains sensitive electronics, that may be damaged by magnetic tools.
I have chosen to use two different types of tweezers as the tweezers with a curved tip, is sometimes better for removing and repositioning the screws.
It is also a good idea to have a straight-edge screwdriver, as it is good for prying of connectors and plastic-rollers.

Executing the repair
Taking the lens apart, was done following the aforementioned Youtube video.
My lens had a few differences, among others one of the flex-cables were glued to a piece of plastic, but on the whole, the guide could be followed and I ended up being able to remove the aperture assembly.
Aperture assembly after resoldering
Removing the old, damaged flex-cable was rather difficult as the soldering iron will easily melt the plastic or remove the solder from the inside of the aperture motor magnet.
I actually thought that I had unsoldered the contacts in the magnet, but finished the repair just in case I hadn't broken it. Luckily the aperture worked.
But if you know how to solder, give it a try, if you break the aperture assembly, buy a new one, it is cheaper than getting the lens professionally repaired.

Reassembly was pretty much just the reverse of taking the lens apart, but take care that the lens parts are replaced as they were, some parts can easily be turned 120 or 180 degrees and still be reassembled, but the lens might not zoom or focus.

The broken flex-cable
As the malfunction was not permanent, but only occurred at certain zoom-lengths, I knew that the cable would not be completely severed, but I was surprised to find that there was nothing visible wrong with the cable whatsoever. However when I compared the replacement cable and the OEM, it was clear that the new cable was much thicker, not only in the plastic casing of the cable, but also the wires look thicker.

Testing the camera
For testing the camera, first I wanted to try out the aperture motor, as I feared having broken the motor while unsoldering the flex. I tested out the aperture motor, by putting the camera in 'Av'-mode (aperture priority) and while holding down the DOF-button, running through all possible aperture settings.
I did this at all zoom-lengths and kept an eye on the aperture iris, it moved smoothly from f/4 all the way up to f/32.
Afterwards I tested the aperture motor sensor, by taking pictures at different apertures and different zoom lengths. I didn't get any error messages and therefore I assume that the problem has been fixed.

So in conclusion, a fix that would cost at least £160 and take weeks at a Canon dealer, I spent a total of £2.31 and used 3 hours.
In my opinion, anyone who has basic skills at mechanics and soldering, should be able to accomplish this repair, considering the price of the lens, you really don't have anything to loose.
Hopefully my lens will work perfectly for years to come.

Monday, 13 February 2012

Back to posting, with a few nightshots.

Lately I have been having fun, photographing my car at night, I like the effects that you can get with different lighting, i.e. flashlight, street lights or the moon etc.

Canon EOS 60D - Canon EF-S 17-85 f/4.0-5.6 (17mm, f/9, 30 sec., ISO-1250)
In this first picture I used a high-power LED flashlight, to get some extra light into the scene, without making the night sky too bright. Moving the flashlight quickly, makes sure that the car is not to bright in some places, and to dark in others. Also this movement gives an added effect in the picture. On this particular night, the moon was very bright, and this made it even easier to make sure the scene was properly exposed.
Canon EOS 60D - Canon EF-S 17-85 f/4.0-5.6 (17mm, f/10, 70 sec., ISO-400)
Shot at 17mm, making the foreground very big and giving an illusion of extreme depth.
There was a lot of street lights, so it was easy to get a well-lit picture, with a great degree of detail.
Canon EOS 60D - Canon EF-S 17-85 f/4.0-5.6 (Merge of several photos, with different settings)

Tuesday, 1 February 2011

Slow updates, sorry.

As I have started working at DEMA (Danish Emergency Management Agency) I might not update the blog as often as I would like.

If you have any suggestions with regards to topics; comment, and I will take a look at them and try and write a post on it.

Friday, 21 January 2011

Another Night of Photographing.

Last night was perfect for nightshots, so I went on a little phototrip and kept snapping away untill both of my batteries were depleeted.
Here are some of the best pictures:

Also I got a great shot in the afternoon just as the sun was about to set:

Thursday, 20 January 2011

ISO-speeds: What is the difference?

Many new photographers ask the question: "What is ISO-speed and how does it affect my photos?".
I didn't know this when I started shooting with my DSLR, I did a little searching and figured it out:
In a film-camera, the ISO-speed determines the light-sensitivity of the film surface, in a DSLR it determines the light-sensitivity of the sensor.

So what does this mean to you, when you are taking pictures?
Basically it is very essential to getting good pictures at different light levels, choosing the correct ISO-speed can mean the difference between getting a clear shot or a grainy/blurry/underexposed one.
Many people wrongfully believe that ISO1600 is the best thing to take pictures at, giving the best photo, why?

 - It gives shorter shutter times.
 - It takes up more space on the memory card.
 - It drains the camera battery more.
 These are all things that would make a camera beginner think: "It gives all those disadvantages, so the image quality must be better for it!".

But in fact there are entirely different reasons for all of this:
The shorter shutter time, is due to the increased light-sensitivity making the camera able to create an image with less exposure time.
The space it takes up is due to noise, noise takes up more space, than actual image data.
The sensor uses more power when it's sensitivity is increased.
The actual result of changing the ISO-speed can be seen in the example below:

All taken with a Canon EOS 1000D with a Canon EF-S 18-55mm MKII, taken at Av with f/22 (enlarged to show quality)

When the image is not enlarged, the grainy, high ISO images looks the same as the others.

As it can clearly be seen, the ISO100 to ISO400 are pretty clear, but anything higher than that, gives a lot of noise.
the camera settings for the photos are as follows (all taken at f/22, because higher exposure times gives more noise, and makes comparing them easier):

ISO100: 3.2seconds shutter time, 2.00mb space required.
ISO200: 1.6seconds shutter time, 2.23mb space required.
ISO400: 0.8seconds shutter time, 2.69mb space required.
ISO800: 0.5seconds shutter time, 3.09mb space required.
ISO1600: 0.2seconds shutter time, 3,89mb space required.

So what speed is best?
Under these circumstances: ISO100-ISO400 are pretty much the same quality and at 3.2seconds shutter time, camera shake is a major problem if the camera is handheld, so ISO200 or ISO400 would be the best, if you have a high capacity memory card, go for ISO400 in this case.
In this case low ISO-speeds are best, but if it is dark, you don't wanna use the flash and you don't have a tripod, a high ISO-speed is the way to go.

If you are in doubt and you're in a generic situation, you can't really go wrong with ISO200 or ISO400, if the picture is shaken go higher, if the picture is grainy go lower.

If your lens has Image Stabiliser, you might be able to go to a lower ISO-speed, without the camera shake.
If you are new to manual ISO-speeds and you are shooting something that you will not get a second chance on, play it safe an choose automatic ISO-speed until you have mastered the manual ISO-settings.

I am not a professional photographer, all the information in this guide is based on personal experiences, Internet searching and the example images displayed above.
As with any photography-technique trial-and-error IS the way to go, this is just a guide to point you in the right direction.
High ISO-speeds are not bad, they are there for a reason, but don't use them if you can get a good photo at a low speed.

Monday, 17 January 2011

Going Pro (sort of) Part 1 of 3: Upgrading to USM

Recently I purchased a Canon EF-S 17-85mm IS USM.
This is widely regarded as one of the best value for money lenses on the market, it is extremely versatile and it has a genuine ultrasonic focus-motor, giving fast and accurate focus, without all the noise and jitter, also it has full-time manual focus and image stabiliser.
Canon EF-S 17-85mm IS USM f/4-5.6

While the kit lens that came with my camera (Canon EF-S 18-55mm mkII) is an alright lens for family and vacation photos, it does not serve the EOS 1000D right, it lacks capabilities and only has approximately 3x zoom.
Besides there is no point in buying a DSLR if you're only going to use the kit lens supplied, then you might as well buy a top of the range point-and-shoot camera.

The 17-85mm USM gives you the capabilities that makes it perfect for an all round lens:
 - Full time manual focus
 - Ultrasonic focus
 - 5x zoom
 - Internal focus
 - Image Stabiliser

All these features makes it the ideal lens to keep on the camera at all times, it doesn't do one thing perfectly, but it does however do a lot of things really well.
I have decided to buy the optional lens hood (Canon EW-73B) to avoid glare and protect the lens.
Lens hood attached

I will post a comprehensive review later, when I have gotten used to the lens and have example photos to show.

Next in this 3 part series: The Canon BG-E5 battery grip.

Friday, 7 January 2011

First attempts: Monochrome Photography

A few days ago it was really gray, which gives a really dull and boring photo, colours need light to really come alive.
So instead of trying to get bright, radiant colours out of nothing, best remove the colours all together and make a monochrome photo (black and white).
Although great monochrome pictures can be taken without radient colours, it still requires high contrast areas, otherwise it wouldn't be easy to see details in the photo.



In this picture I wanted it to look a little old-fashioned, but still with the clarity and quality of a modern photo, I achieved this by snapping the picture in RAW-format and converting it on the computer, also I took this picture as an HDR (High Dynamic Range), meaning that I took 3 photos with different exposures to get better contrast in the image.

These pictures were taken with the same technique as the previous, but processed a little differently on the computer.