Photography Hack a macro lens from a zoom lens

I decided to make a more permanent macro lens.

The improvised one here was just too crazy to use. Everything had to be held together with tape, string, and luck.

It turns out its pretty easy to hack a macro lens, if you already have a short zoom lens you dont need.

There are a lot of canon kit lenses that came with the cameras floating around out there for only a few dollars. The best price I saw was $3.98 US.

The lens Im using is a canon EF 35-80mm zoom. I got it for free from someone who paid around $5 for it in Japan.

 The first step is to find some screws that might let you get inside.

The object here is to remove the front lens element.

My screws were found under a sticker, but different lenses hide the screws in different places.

Removing the sticker revealed 3 screws.

The sticker is useless after you remove it, so dont try this unless you want the change to be permanent.

Thats the wrinkled corpse of the sticker in the background.

Undo the screws.

This allows the top lens element to be removed.

This lens cluster does the focusing as far as I can tell.

At this point you can take a macro shot, but the lens will leak a lot of light onto your censor. The black plastic surround covers a gap between the outer lens casing, and the inner sleeve that controls the zoom.

In my lens, it wasnt possible to remove the lens from the plastic surround, so I had to cut it off.

If you were trying to do this as a temporary thing, and wanted to try it before you commit, all you need to do is cover the lens front with something light proof with a hole around 2cm in diameter in the centre.

Im guessing gaffer tape would work well.



The main thing is to create a cover for the gap between the outer casing and the inner zoom sleeve.

The lenses are of no use, but the plastic surround is very useful, because it has a screw thread to take filters.

A clear glass filter, or a UV filter will be the thing that keeps dust out of the lens.

The large black plastic thing is the bit we are keeping.

There was an extra hole that I filled with a screw to keep everything light tight.

A clear glass filter, and its all done.












The results are pleasantly surprising. The original lens could zoom into around 6cm in width. This is closer to 1cm.

The focus ring no longer does anything, but the zoom still zooms. 

There are two ways to focus. 

Moving the camera or the subject until the scene is in focus is where you start. The distance from the lens that the subject needs to be is only around 5cm. Once you have the subject roughly in place, you can use the zoom to change the point thats in sharp focus. 

The zoom also works as a zoom, and changes the field of view between 12mm and 25mm from one extreme to the other. ie at full zoom (as per the shot of the pencil, you can fill the frame with a 12mm object)

All in all, not quite as functional as a proper zoom lens, but for $5 it represents a pretty good compromise, and something Id call a total success.

120 Things in 20 years - If canon just made the front lens element removable, I wouldnt have needed to do this lens hack to convert a zoom lens to a macro. 

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Photography Improvised macro lens mould study

I got another lens from a junk bin in a camera store.

This one is a canon f 1.4, 35-80mm zoom.

It has an auto focus motor that makes a sound a bit like you might hear if you put a blender in a blender, but the auto focus still works.

The bits that dont work so well, are the lenses.

The problem is mould inside the lens.

Not uprising for a 500 Yen lens sitting in the junk bin of a camera store in the country that invented humidity.


Thats a ridiculously close up shot of the mould.

Ridiculously close up.





I dont have any way of doing macro shots with my new camera, so I had to improvise.

I took the shot of the mould with this home made bit of kit.

The blue lens cloth is there to keep the light out of the improvised macro lens, because the small length of toilet roll acting as an extension tube  isnt light tight.

The lens attached (thats a generous description) to the camera is actually on backwards, and is resting against the other end of the toilet roll tube.

The lens resting on the red kitchen scrubber is the new one with the mould garden inside.



The torch is a torch.

The torch is there because the cameras lens has the aperture set as small as it will go (f36) to try to get at least some of the mould in focus.

I didnt really achieve that.

The exposures were around 30 seconds long (many minutes without the torch), and other people were working in the house at the time. My desk is a wobbly kitchen table top heavy with old CRT computer monitors, and all the other junk I like to keep at hand. As as a result it amplifies any movement from people, traffic, and the fridge and freezer compressors.

If you put a glass of water on a desk like mine and look at the reflection, you will see the reflected image dance all over the place. Normally it isnt a problem, because the camera and lens would both move at the same time, but with this contraption, there was nothing of substance connecting the lens and the camera.

Tricky.

Anyway...

The lens has mould in it.

The image on the left was taken with the canon 18-55mm lens that came with the camera.

The image on the right is taken with the mouldy 35-80mm lens.

The camera was set to the same settings for both shots.



Mould is not a friend of the lens.

The point of all this, is to point out that I wont be taking an angle grinder to my lens in some future post  without reason.

Actually Ill try to open it up and clean it, but there is a fair chance its bits of glass are coated in a very delicate plastic coating, called coating. If thats the case the mould may have become a permanent fixture by etching its way into the coated bits.

The mould appears to be on only one element, so I might be able to salvage some other bits and make a proper, mould-free macro lens.



120 Things in 20 years warns that when I say "proper" I mean the improvised macro lens might employ slightly fewer toilet paper tubes, and where they are unavoidable, they might be made a bit less wobbly and light leaky.

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