Yoshizen's Blog

Humble Lens (?) for Canon Camera = Pinhole Photo / BGR Tri-Pinholes Photo

You might think the Photo here is yet another bloody Soft Focus lens.

It’s not by Soft Focus lens. —– In fact it was not even a lens at all.

——– ( Like latest  5D Mk-III,  5D Mk-II also has Light-leak or it might have caused by the internal reflection

———  on a shiny surface of a parts.   Canon can say, it is not in a normal use what camera was designed for)

This is a Pinhole Photograph on Hi-Tech DSLR —– ! ! !

You might be surprised —– or bemused ?

(End of this post, you can see  3-pinhole photo with BGR color-filter for each pinhole )

—————— ( Cutty Sark in Greenwich —– Hand held Pinhole camera, F250, 1/15th Second, ISO 3200 )

One of the best advantage of the Canon EOS cameras is, their Light-measuring

function works  without any lens attached on the body. = Light was

measured on the light actually came into the sensor, and the exposure value

was calculated on So-called Stop-down Metering.

In comparison, other cameras are guessing the exposure based on the

information came from the lens, mounted on the camera. Its mean, their

camera was designed to work only with a ROM memory hidden inside of the

lens which gives the information of lens ID, what is the current setting of

focal length on Zoom, F-aperture setting (in a case such as Nikon which allow

you to use an old manual lens) etc, with an assumption of the lens would

work accordingly.  (If the lens was F4 in full open, calculates how many stops

needs to close in this lighting condition.  Canon measure actual light instantly,

when F-aperture was closed, then select the shutter speed).

The reason why other manufacturers are using this design was, to prevent

the use of a lens other than their genuine products.

(The ID of lens would direct a correction program,  such as to brighten up

the corner-fall-off of the wide-angle lens).

——–  — ( Cutty Sark in Greenwich ) ——— ( There was a Cinema Film Shooting at Old Royal Naval College )

On the beginning, in order to cut into the Nikon dominated professional

camera market, Canon designed their camera even capable to use with

Nikon lens.   Hence, in the early 70th, they sold a lens mount adapter to use

for Nikon lens.  (Later, when they gained popularity and their confidence grow,

they stop to sell this adapter). 

The First Gulf war was the turning point for the choice of professional camera,

as most of Nikon were stopped to work, thanks to the microscopic sand dust in

the desert.  Only the camera kept working was the Canon. —– As a consequence,

News Photographers changed to Canon.

Still, the tradition to allow the use of Nikon lens was kept by Canon, since such

as special 2000 mm lens which was made only by Nikon, Canon has to make a

provision for News photographer to use such special lens on their Canon body.

= hence, camera was designed to functions with the lens which has no Canon

ROM memory.  In other words they can work with any lens. 

So that, their camera, even Digital SLR can give enough exposure function except

Tv and Program Mode. = still perfect on AV Mode and of course with

Manual Mode.

Above all, with DSLR, we can check the result on the spot, and change

manual setting or exposure compensation on Av.

( Or, change ISO setting further).

——————————————————- ( At Painted Hall, Greenwich )

So, there is no problem to use Canon with a reading glass, plastic flat lens

(Fresnel lens, which gives utterly unsharp image 😀 ) —– even with

Pin-hole, while leaving all the exposure control to the Camera !

= Just use AV mode and adjust exposure compensation.

(Though, Canon 5D gives only up to 30 seconds on AV Mode, if you need

longer exposure to make picture brighter = increase ISO to higher setting,

or change to Manual Mode.

And if you need to have very long long exposure to make all the moving

things disappear, use lower ISO or use dark ND filter together.

Unlike on color film, the adverse effect of UV light  (which causes blue cast),

doesn’t affect the color on Digital camera.  But never have a direct sun in

the image.  Without having any protective glass lens which blocks UV light,

it may damage the Image Sensor).

————————————————————— ( At Greenwich Town )

And, to do this kind of creative shooting, you need to pay attention to

[Good Common Sense] such as, to use View finder cover to block the

stray light from the back.  

And use good black paper for making Pin-hole, and make sure, pinhole

should be clean round hole with no paper floss messing on it.

And DO MAKE SURE, keep everything DUST FREE. 

Wash your hand before hand.

= a dust particle got onto the Image Sensor is very tricky to clean.

Your acute mindfulness was required.

——— ( Sake of photo, Pinhole was placed on EOS RT body )—– ( To make a perfect hole, it was made on a smaller

———————————————————————————————- piece of thin metal and attached in the center )

A paper with Pinhole, will be stacked on the lens mount of the body by a black

PVC tape to seal-off the stray light.

The Canon DSLR camera has the depth = Flange-back (Lens mount to Image

Sensor) 44 mm, therefore the field of view is the same as 44 mm lens. 

And if you use an Extension Ring and stick the pinhole further away from the

body, effectively it would give you telephoto images.

In the most of the case, (as a fine sawing needle has a diameter about 0.5 mm)

the size of this hole is equivalent of F90. (With a focal length of 44 mm lens,

if the diameter of the lens was 44 mm, it would give effective F-aperture F1,

hence, 44 /0.5 = 88 = about F90)

—– I’ve made it less than 0.2 mm = F250.  Instead to use a paper, I used thin

aluminium panel of a Drink Can, and pierced it with just a tip of the needle.

The smaller the hole, it would give sharper image though, the optical effect of

Diffraction will scatter the light, it can not give sharp image like an optical lens

anyway, but on the other hand, it gives pan-focus. 

(The hole doesn’t necessary in the center = You may put it far side and take

picture always one half, like top-end.  Or to put TWO, to make double images,

or one with color filter and so on, there are endless possibilities,

still cost nothing.  😀 )

—– (The samples of 3-PINHOLEs photos with each Red, Green and Blue filter)



—– It would be a fun to play with a camera in open-minded way.

(Try it and find new play ground in photography  😉 )

[]

Advertisements

6 Responses

Subscribe to comments with RSS.

  1. drawandshoot said, on April 20, 2012 at 03:11

    I really like the flowers and the Cutty Sark, Yoshizen.
    Interesting conversion!

  2. yoshizen said, on April 20, 2012 at 05:17

    Thank you very much karen.
    It was not a kind of conversion, = just stack a paper which got a hole 😀

  3. […] flexible funny art,  such as even pinhole photos are also the photos.   […]

  4. […] —– to get this effect, I tried many Soft Focus lenses, Filters, Pinhole Photo, […]

  5. […] Nikon needs to have Non-CPU lens set-up. […]

  6. […] Simple Single Pinhole, up-to-4 Multiple Pinhole and Concentric-DD Pinhole […]


Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out / Change )

Twitter picture

You are commenting using your Twitter account. Log Out / Change )

Facebook photo

You are commenting using your Facebook account. Log Out / Change )

Google+ photo

You are commenting using your Google+ account. Log Out / Change )

Connecting to %s

%d bloggers like this: