F-Aperture / Iris Control

As I wrote in the previous posts, I have recycled rear element of the

broken Zoom lenses to use for the macro photography.  Both of them were

Canon EF type lens which has an electronically controlled Diaphragm / Iris.

Electronic Iris has an advantage, they  only needs electronic connection,

not a rigid mechanical connection though, this electronics is not just a cable.

—– If the recycled lens was maintained

all the electronics as before, Iris could 

be controlled by the camera side. 

But when the lens was stripped down

to Iris and its Pulse motor,  it is

necessary to create a driving circuit 

for the motor. = And this Pulse motor

needs to have a specific alternating pulse.  

So that a Pulse generator and a Full-bridge

driver would be needed.

(If you would like to know about those pulse motor and its proper control,

please Google  >>> Bipolar stepper driver schematic )

Electronics is a funny phenomena.  It can be elaborated to have Hi-Tech

sophistication but in the same time it still works in a very primitive way.

= Such as the Electro-Magnetic device could be as sophisticated as HDD, still,

if you wind a wire around an iron nail and connect it to the battery, it would

work as an Electro-Magnet and pull the other iron pieces. 

To drive such pulse-motor, there are many IC chips in the market though

most of them are for higher voltage.  I needed to make it using discreet

components = as long as it generates alternating pulses, the Iris works.

(The original driving circuit has a PWM = Pulse-Width-Modulation for

smooth and quiet operation, but here better not ask too much)

The photo above is a circuit to open-close the Iris in the cannibalized

rear element from a Sigma Zoom lens.   (Can drive Canon’s  as well !)   

(Circuit was too simple, I didn’t even bothered to use Prototyping Beloboard

—– just soldered together. = as long as it works, good enough to test)

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From the test, I found the circuit was just enough = no frill, bare minimum.

(Ideally the F-Aperture value indicator may be needed though, in practice,

I may not need more than “Fully open for focus — close down for shooting”

= I decided to put only  two switches, open and close. ~ ~ ~ When the building

work progressed, I’ll show the new photos.  🙂

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PS:   WP noticed me, this is not only my 602nd Post but this is also the

Anniversary of 5 years  on blogging. —– gosh.  😀

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Good Lens or Cheap Lens

Some regular reader may remember, this lens has appeared here before.

But if you look inside, you may noticed that this one doesn’t have shiny

blue beer can.  = In deed, the front lens is the same though, the panel, and

the pinhole inside is different.  I did swap the panel to single pinhole hence,

it still has semi-fisheye wide angle view but the image doesn’t have a

hallasion created by the Double Density Pinhole.

The front lens came from an ubiquitous cheap Fish-eye Adapter, therefore,

giving fish-eye like distortion and wide-angle view, but being as low cost =

single lens structure showing the Chromatic Aberration.  = Part enlarged

bright-spot of Photo above, rainbow effect is quite visible.

Theory was the same = ” Place a strong concave lens before Pinhole would

creates [Wide angle Pinhole Image]” and this one has a concave lens from a

Canon Zoom Lens. = which is in deed the front element of the same lens I’ve

experimented with its rear element in the previous post.  

And I put the same Double-Density Pinhole panel behind of this lens.

This Canon’s Zoom was EFS type 18~55 mm hence, it was a kind of

medium wide-angle, so that even a front element concave lens was not too

strong = giving modest wide view.  (Though, still having quite a distortion.)

Yet still, the lens carrying the quality of the Canon = this front element

has an Achromatic design = no Chromatic aberration was visible. 

So that, thanks to this high quality Diopt-Pinhole Photo System, on a

full-frame 5D Mk-III camera, I can take high-quality Fuzzy image !

(I’m serious, believe me.   Ha ha ha  😀  😀  )

———————–

IN ADDITION:  This is the front element from a Sigma Zoom Lens.

Lens came from a friend of my friend who gave-up to repair the lens.

(The person managed to disassemble though, couldn’t put it back.)

It seems Sigma was used all sorts of clever tricks to produce the lens

“Reasonable”= not superb, still good enough, light and small, and

most importantly, not expensive for the people of this class.

The front lens seems to be plastic = easy to be scratched (Photo Left)

and the Photo Right shows funny reflection = this is an “Aspherical Lens “. 

You may have a fancy illusion toward the Aspherical Lens. = Yes, Aspherical

lens can give superb optical quality though, these days, it was used as a

magic bullet to save a cost !  (Instead to use many heavy and expensive

Grass, just one plastic Aspherical Lens could eliminates the aberration.)  

Because, Aspherical lens is no longer difficult to make nor expensive.

= Computer give the design and the laser curving can make a precise

die-cast, then the rest would be just a plastic mass-production work. 

As a rather ordinary  x3  Zoom, the strength of the front Concave lens is

similar to the Canon’s Zoom shown before.   The front element consists

two lenses hence it supposed to be an Achromatic design —– though

photo above shows the Chromatic Aberration. (See the rainbow color.)

(of cause, it might be corrected together with the rear element.)

And I put a single pinhole behind of this lens.

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Junk as a Macro lens

Camera lens is the optics = even if it was broken and ended-up in a bin,

lens can still function as an optics.  Convex lens can project an image.  

This lens was a Canon zoom lens which I got free from a camera shop.

Top left of the photo above, is the rear group of the Zoom lens which function 

as a convex lens to project the image.  Convex lens mean, it will work as a

magnifying lens and in reversed direction, it could be a good macro lens.

—– for a fun, I tested this lens unit to take macro photo.

(on the photo, you can see a L-shaped plastic bar on the lens-unit, there were

three of those which held the lens unit in the position though, such flimsy

plastic couldn’t survive a shock and easily broken but impossible to repair, it

was the end of the life ! — replace whole unit may cost half of the lens price.) 

For macro photo, lens unit was stacked on a mount adapter ring using sticky

plastic-pate, and it was mounted on

Canon 5D through 2 sets of Extension

tube. (total extension was 125mm) 

—– After few shots, I found the

sharpness wasn’t good enough,  

so that, I closed the Iris somewhere

half-way. (Photo left)  

This Aperture / Iris  has a

stepping motor built inside

= So, I’m going to make electronic circuit to drive it. 

And, this is how the photo was taken while using a small flash-light.

The photo wasn’t too bad —– considering the lens came from a bin.  😀

This lens unit act like a 38 mm lens, so that it can produce about  x5 macro

image on this extension.   The photo above was a clopped part-enlargement.

(effectively,  x10 magnification = 3.6 mm object was on the 36 mm frame)

Originally, this was a rear half of the good zoom lens. —– Think about, it

is a magnifying glass of £100 cost = it got to be high quality !

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Parts Box ?

To make, modify or repair something etc. what ever to do, it’s always need

to have all sorts of components or parts. —– strange urban myth was that

I’m a kind of professional, so, I have a professional class storage / drawer

box to sort the components.  And people are believing that I got a workshop.  

Wrong !   I’m a non of professional.  Therefore, I’m keeping the components in

the most unprofessional way.

= My storage box for the parts is “plastic Ice-cube tray” used in a fridge. = This is

the most compact and convenient way to keep the small parts in order.

(And cost virtually nothing.  🙂 )

Even just the screw, there are many different sizes, starting from  1mm~.  

About the same size but old  1/8″ doesn’t match to metric 3mm screw.  

So, they has to be kept separates, ETC, ETC !

Situation is far worse in the electronic front. —– if I got to store everything,

I need to have a space, size of a shop.  

So, I keep the items handy I most likely to use, in the Ice-cube Tray.   

I don’t remember when I got this and started to use. —– I might have

brought those from Japan = it’s mean, I’m using this, past  40 years !

For me, the matter is its function.  = as long as it fulfils my needs, that’s enough.  

And, even more crucial matter is  “What I do with those components”.

Parts are just a matterial.  Part wouldn’t creates anything. = Thousands tons of 

cement is not a building.   And the beautiful way to pile-up the cement neither

form a building. —– Building would be counted when it was elected.

So does the component here, when it became a part of a finished product,

it would be counted as a meaningful existence.  (but thousands end-up in a bin)

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Small Repair

In our daily life situation, when

something break down and need to

be repaired, in most of the case it is 

a loose screw or loose connection

kind of very simple fault.

In certain extent, it is true that the

everything break and lost = natural

were ant tear surely eat away its life

though, in the same time if we pay 

reasonable attention such as to give an oil or tighten the screws etc, the things

can last quite long time.  Like my Electric Kettle, it is more than 30 years old.  

In fact, there is little possibility of a Kettle to break down unless switch

it on without a water thence either whole Kettle melted down or burn-out the

heater element.   It’s mean, if we do “Always put only necessary amount of

fresh water and boil” = Kettle was designed to last for ever in this condition.

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But a kind of machine which has a motor inside, its vibration often cause a

break down.  The worst was the worn-out of the motor bearing (due to a rack

of care = dust,  and rack of oiling) otherwise,  a component became loose.

Photo on the top is a control board of a motor tool in which you can see an

exploded component called Triac.

The vibration caused a component to come loose and caused a short circuit.

The damaged parts was visible and the repair was simply to replace and fix them. 

The photo above is a control board of a back-up battery power supply.  

Right side in the left photo, you can see a yellowish box shaped component

was burnt and exploded.  From the shape and the size, it’s easy to see that it

was the same one in the left side, which said 100mF = It was a capacitor.

Remove the damaged one and test with equivalent component, if the whole

unit works (it’s mean no other component has been damaged), it’s the repair.

In this very case, the damaged capacitor was replaced by the equivalent

capacitor (in the photo right). —– But, if no obvious damage was seen, then

complicated trace and analysis game starts.  It’s mean, this  is not a small or 

simple repair. —– Some time it was called nightmare and often

it is cheaper to buy new one.  😀

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Too Early Magnolia

When I saw this Magnolia, I was even annoyed by it.

It is definitely wrong — gone too far.

Cherry can flower earlier but not this variety of magnolia.

Normally, this tree flowering after the Cherry — in May.

Without a reason, I have strange soft spot to ancient plants.

 Cycad, Tree-fern, Horsetail, Ginkgo, Yew, Monkey-puzzle, Magnolia, Lotus, etc.

For them to survive hundreds of millions of years,  they must

have a supreme wisdom printed in their gene ! —– I feel awe !

So, what’s wrong with she in this time ? ? ?

Those fuzzy images were taken by Wide-angle Pinhole on Canon 5D Mk-III.

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Electronics in the Lens

Lens of today’s hi-tech DSLR was connected to the camera body

on its bottom, mechanically and electronically.

Except the Canon EF Lens (for EOS), the Aperture lever has to be

pushed from the camera side, therefore when the lens was used in

rivers direction, either the Lens become completely manual (if the 

Aperture ring was still there) or just out of control. — But Canon’s EF

lens has its own stepping motor to drive the Aperture, hence as long as

they are electronically connected, the Aperture will function as normal.

(If not connected, there is no way else to use Aperture but fully open.)  

To have an electronic connection, we only need a simple cable !  

So, I made this adapter, long time ago, in fact soon after the Canon

introduced their EOS camera. ( yet, it was a film camera then.)

—– the connection between the camera and a lens was made by two

sets of male and female contacts. = I made and mounted them on

a Body-cap and a Lens-rear-cap,  and jointed them with a cable !  

= With this cable, even when a lens was held in angle, still the

lens function like as normal.

I could use this on EOS 620 and RT with EF 28 mm lens for

experimental close-up with tilted lens etc —– though, few days

ago, when I tested this again, with my latest Canon gear, 

I found, 5D camera refused to work with this.  😀  😀

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On the appearance, it was just an 8p connections and two of them

were the ground line, and the signal lines for each direction =

only 5 lines seems to be used though, as long as all 8 lines were

connected one-by-one there should be OK, other than the trouble of

impedance or magnetic interference kind, caused by an extended wires.     

(Those interference might be used to detect unauthorized connection.

And if anything odd was detected, Camera CPU may check the Lens’ ID.

—– If no answer was received, then camera stop to work normal.  🙂 )

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These days, the lens transmit their own ID for their own graphic program

to correct the individual characteristics of the lens, such as the aberration

or corner fall-off of the light.  = To correct the Chromatic Aberration,

Red signal from the Pixels would be shifted inward and Blue signal would be

shifted outward accordingly ! (So, the picture become even sharper !  😀 )

Though, I’m not necessary happy with this kind of approach —– once we

start to rely on computer graphics, we may no longer need to have such as

ultra wide angle lens or fisheye-lens, as we can get the same effect by

stitching the photos or use distorting graphic effect or “filters”.

Graphic design is a desc top process, it is not a photography on the spot.

Photography is a Site-specific, Moment-bound “interaction”

not just a visual effect.

= What “I” witnessed and how I lived with its moment  IS  the matter.

If the artefact left was a fake, the person and the life was a fake. 

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At a moment, I’m quite amazed how  Canon 5D  could detect

“something odd” about this cable, and teasing me while showing

photo-number [50] in the view finder, instead of [950] on the

camera top,  and not showing “Focused” indicator  etc.

—– not malfunction but maliciously falsified on purpose.  😀

(It takes time to debag and hack-into the camera. )

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Deptford — Art or Odd ?

In south-east London, just before the Thames River reaches to Greenwich,

it is the Deptford.  Unlike the posh Greenwich, this part of Lewisham is

rather poor area = hence lots of artists (I guess, rather poor artists) are

living in this area =  And it creating very distinctive atmosphere here

though, I wouldn’t necessary say it is artistic, but definitely it is odd.  🙂

Next to the Deptford open market, the Albany Theatre is

one of the center of the Community Art activity.

But half of the market is a Flea Market = or some might say junk heap.

Therefore, to distinguish Deptford’s  “distinctiveness” = whether it is

art or junk is a difficult task.  😀  Photo above left is — can you guess,

it’s a tattoo shop !

The area having quite a number of Vietnamese population hence

many Chinese-Vietnamese restaurant as well. 

And number of Charity shops (or junk shop). —– Important point is,

they were sold to the grown-ups, not to the children.

On the table, Permanent flower in a glass jar = What a great idea !

—– I’m wondering, who got a courage to cut a hair there ?

—– or the population here loves a joke so much ?

And so-called Laughing Buddha (Chinese Putai = Taoism figure, nothing

to do with Buddhism) must be a warning of obese in the restaurant.  🙂 

They are the Wedding cake kind ! = What a fantastic idea again !

So, where ever you go, ART (sort) is everywhere.

This is what Deptford is !

(Photo Right is, the entrance to the Site-office of construction site !

= not a joke ! )

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Most fancy Macro-photo set-up

This is a rather fancy combination of the macro photo set-up,  

around the famous Olympus 80 mm F4  1:1 Macro lens.  

This lens was designed for 1:1 Slide duplication or inter-negative work.

Most of the Macro Lens was designed to give the best performance at

1/10 shooting distance.  (Ordinary lenses were designed for the infinity.)

So,  this Olympus lens was quite unique even among the macro lens.

—– though, this lens was designed to use on the Extension Bellows,

I was thinking to make an adapter to use the lens on a bellows like this.

—– then, I found a fancy (and very rare) camera accessory “Pentax,

Helicoid Extension Tube” together with “49 mm to M42 Reverse ring”

= in this combination, I can use this lens without a bellows.

From the Left, Zuiko 1:1 Macro 80 mm F4,  49 mm to M42 Reverse Ring,

Helicoid Extension Tube,  M42 to EOS Adapter ring, EOS Extension Tube  

and EOS 5D MK-II Body.

Unlike the previous photo by 24 mm lens,  rather long 80 mm lens can

give more even view and giving a ease of lighting. (This is x1 or 1:1 shot)

Clopped and part enlarged image isn’t too bad to the 24 mm original x10 image. 

F4 is not very bright for 80 mm lens, still the out of focus bokhe is quite

large and soft. —– (But a little bit messy.  🙂 )

Looks interesting image though, whether this image is better than such

as Tamron 90 mm F2.5  or  Canon Macro 100 mm f2.8,  it’s need to have 

a test shot in the exactly  the same setting and the lighting.

(I might add the photos by those lenses later here. )

—————————–

PS:  When I posted this, a reason why it became so fancy was that I didn’t

have Olympus-EOS adapter —> hence, I needed to mount the 80 mm lens

reversed = since I couldn’t use 80 mm lens’ own helicoid, I needed to add

Pentax Extension Helicoid and so on !

—– Since then, I obtained an adapter => I can mount the lens in normal

direction straight onto EOS Extension Tube. = Here the simpler configuration.  

When this lens was mounted about 80 mm from the Image Sensor, it focused

to infinity.  And with 80 mm more Extension Tube, it creates life-size image.

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Tripod — give a thought

Among rather delicate Photo equipment, Tripod is exceptionally physical.

No another equipment would be thrown into a car floor. —– and may be that

was a reason why a film company disposed and gave a broken tripod to me.

When I got a huge Bilora tripod (Photo Left),  it’s legs were crushed. I replaced

them with 3 Manfrotto’s Monopod and put Gitzo No.4 (largest) Tripod-head.

= This 15 Kg heavy tripod can extend to 3 m high(with extension column) and

never produced blared image caused by a vibration, resonance kind. (of cause) !

(I was using this for Pentax 6×7 high-angle shot, or large format 4×5 kind.)

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Center Photo is a rather light-weight Gitzo (Reporter) with Ball-socket head.

Unlike other Gitzo which got 3 axis (X,Y,Z) fixing,

this ball-socket head has “a kind of” ease for quick

adjustment.  In the same time it is a disadvantage.  

If 3 axis can be adjusted individually = for instance, while keeping X,Y

fixed, but change only Z direction, it can have finer control.  

And being as light-weight and thin pipe, (even worse, ball and socket’s joint

is rather thin long neck) this tripod is sceptic to vibrate when all the

combination and the balance of the weight happened to resonates.

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And the Photo right is one of my small tripod (but not the smallest) which

become flat, when not in use. (Easily slip into a bag. )  

This tripod extends to 1 m and fold to 38 cm, the weight is mere 500 g !

It’s a typical case, “Better than nothing” but never perfect in any aspects.  🙂

The most important point of using tripod is, never fallen into an expectation

of false security. = Unless the tripod is really hefty heavy one, the use of tripod

may create more adverse effect = causing the blur.  Somewhere like a beach or

hill side, when the wind was strong, the tripod may be vibrating with the wind.

(You can feel it while rightly touch the leg.)

Test your tripod with your camera mounted —–> Click a shutter while rightly

touching your finger to the tripod leg. = If you feel tripod vibrates,

that is a quality of your tripod ! => Need to become aware of FALSE security !

Then take a measure.  Such as, hung something heavy from the tripod.

When tripod is vibrating, instead to use a Remote-Trigger or Delay-shutter,

grip the camera (on the tripod) and trigger the shutter by your finger !

(Hand works as a dumper. )  —– Or completely opposite approach against

Shutter-shock = drastically lower ISO and the shutter speed and make

shutter speed something like one second to few seconds !  

Unless the subject is moving, strangely, the photo become much sharper.

(See it yourself !  🙂 )

—– From the experiences seeing the broken Carbon Fibre Tripod, Golf club

and Fishing rod,  I’m not a fan of Carbon Fibre.  = When they brake, they

disintegrates.  Broken aluminium leg is still “a kind of leg” = You still able

to shoot a last photo or two on it. 

But, disintegrated bunch of plastic is utterly useless.  

Not to have a feeling of “false security” mean, better carry an insurance

for the worst situation too = carry one Kg more for stronger tripod !

After all, the steadiness and the reliability comes from its solid weight.  🙂

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