Photography Seeing whats inside a canon auto focus lens

Opening up my old camera in an attempt to fix a stuck lens didnt end well, but it did make me want to open other stuff.

A mouldy $5 canon EF 35-80mm zoom seems like a good candidate.

I actually made it work better than it did when I started.

Thats officially a successful repair.

We dont see many of those around here.

Odd feeling.

It turns out I wasnt being all that original when I used a lens cleaning cloth to make my macro lens hack light tight. It seems canon does something similar with a rubber band.

I attacked the rubber grip of the lens by lifting it up with a small flat head screwdriver, and sliding it up to reveal the three screws that control the zoom function.




Once that was done, the lens started falling apart. All it took was finding where the screws were in the first place. All the places I was told to start by the Internet were all false leads. Im guessing things like lenses are made by the lowest bidder at the time, so these things probably change design all the time.

The only real stumbling block was this very fragile looking plug.

Luckily I had uncounted them when I pulled apart my point and shoot canon digital, and discovered they werent really all that fragile.

I covered it with a folded bit of paper so the pliers wouldnt scratch the circuit off and pulled.




I also tried to avoid touching anything that looked like it might be copper. I have a feeling that touching stuff might lead to corrosion.

Probably just being paranoid, but it wasnt any really effort to avoid it. I should buy some cotton gloves for this kind of thing.

The little plug looks like this when its unplugged.

Robots are probably better at putting stuff like this back together, so I took a lot of photos as I was unbuilding it, so that I might have a chance of putting it back together.

Thats a tip.

Take lots of photos of things as you pull them apart.

One part that was really fragile was this little bit of kit.

Its like a switch that drags its contacts along a curved section of circuit board tracks so that the contacts keep in contact when you rotate the lens to zoom.

Or perhaps they adjust the aperture as you zoom, as Ive noticed the available aperture range changes from one extreme of zoom to the other.


Who knows what its really for, but I bent it convincingly out of shape when I was putting the thing back together.

I managed to fix it, but two of the pins will never be the same again.

This is the rear element. (the bit you can see a lens in on the left)

Its a cluster of ... three I think it was... lenses (two at least, but I think one was made of two), that I think also contains the aperture control.

The aperture control stuff must be in there, because there was nothing else with electronics in the lens.

I think this is me taking apart the lens that was really two lenses.

This things all had mould, but the other side of the one you can see in this pic had the most.

This is what I decided was the aperture bit.

I hope this isnt too technical for the reader.

Is bit even a word in this context...

Anyway, the remarkable thing is, after wiping down all the lenses with a lens cloth, it was actually an improvement.

Thats the before and after shots with this lens.

Most of the milkiness is gone, but there is still a bit of mould on the front bunch of lenses, but I think I might hack them off and convert this thing to a macro lens.



Ive been reading up on lenses, and how to hack bits off lenses that you dont want, and turn them into lenses that you do want.

Anyway, not a bad outcome for a $5, brand name, auto focus, zoom lens.

I cant wait to cut bits off it.




120 things in 20 years - Where you will still find someone who thinks a lens doing its auto focus thing is excitingly like having a robot. You also might find someone interested in photography trying to open a lens to see if there really is a man inside who does the focusing. (theres not by the way)

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Making smoked foods Soldering iron cold smoker

I bought some very inexpensive cuts of chicken labelled "Breast roasts for two" from my local supermarket.

They appeared to me to be a prime candidate for value adding.

I brined them in a solution of water, salt, sugar, pepper, and some lemon juice. I also threw in a couple of bay leaves. I have no accurate record of the measurements used.

Measurements are a tricky thing, because you cant rely on one batch being the same as the next. The amount of meat, and its existing water and salt content create differences. You can probably ignore the existing levels, but the amount of meat being brined changes things a lot. The result is you cant just say x amount of water needs y amount of salt.

As I understand it, the process of absorbing the salt and sugar is done by osmosis. Salt is removed from the water, so the amount of meat in the brine changes how much salt is left in the brine. The result is the solution might need to be stronger to brine more meat. Irregular shaped meat like my chicken breast still on the bone, requires a bigger amount of water to cover it.

The good thing is, it will probably work well no matter what you do, but it does make a recipe a bit pointless.

That being said I used about 6 litres of water and a bit over half a cup of both salt, and sugar.

Brine your food in cold water, in the fridge.

After an hour and a half, I removed the chicken, pat it dry, and placed it into my lidded BBQ.

A 12 or 24 hour brine would have been better but I was pressed for time.

I also placed my trusty tin can full of holes inside, and jammed a 60watt soldering iron* into it at the base.

Perfect, cold smoke in minutes.

A total success.

The wood chips were from a store bought pack of smoking wood chips.





Im pretty sure this would ruin the soldering iron for soldering, but this was one Ive never used as it was way too powerful for anything I might do.

Previously I used my tin can full of holes with burning heat beads to keep it going, so I needed quite a few holes to support the combustion required to keep it alight. With the soldering iron, I can choke it down a lot more because it will never go out. I think Ill make a new tin can with less holes, and a large adjustable hole in the top by way of two lids with large holes that I can rotate to make whatever size hole I need. This should allow total control over how much smoke is made, and with some marks on the lids, I should be able to keep a record of what setting it was on, and what worked and what didnt.

But it does seem that everything works, no matter what you do so dont be too stressed over recipes and instructions. Just have a go, and you wont be disappointed.



120 Things in 20 years - Should have done a bit more research before trying to make a cold smoker because a soldering iron works really well.


*using a soldering iron for a cold smoker is NOT an original 120 things idea

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