OCA Exercise 3; Focus at Different Apertures.

Camera: Canon EOS 550D

Lens: 18-200mm Telephoto Zoom f/3.5

Objective;

Take three photographs of the same subject, in this particular exercise, a row of items, similar to the previous exercise. The first image was to be taken at the lens' widest aperture, the second, at approximately the mid point aperture, and the final image at its smallest aperture. I set up my camera on a tripod as advised, and focused on one point, somewhere near the middle of the frame (8^th pot from the left).

             Photograph Number One; taken at f/3.5 (widest aperture)

            Photograph Number Two; taken at f/11 (mid point).

             Photograph Number Three; taken at f/22 (smallest aperture).

                 Photograph Number One; taken at f/3.5 (widest aperture)

    

In the first image above, it is clear to see the depth of field is shallow, the in focus area starts between the 3^rd and 4^th pots, and finishes between the 12^th and 13^th pots.

       Photograph Number Two; taken at f/11 (mid point).

Sharp focus in this image is greater than in the first image due to the smaller aperture, thus giving us a greater depth of field. The DOF starts between the 2^nd and 3^rd pots and finishes between the 23^rd and 24^th pots.

       Photograph Number Three; taken at f/22 (smallest aperture).

The depth of field in this final image is even greater than in the first two, however it is only noticeable in the foreground of the photograph. When I compared photograph number two and three, I could see very little, if any difference in depth of field towards the background of the images. In this image, the DOF starts at the far left of the image and finishes at around the 25^th pot.

Conclusion;

During this exercise, I have learned that the smaller the aperture, (higher f number) the greater the Depth of Field (DOF), and thus a larger area of the image is in sharp focus.

A smaller aperture does not always give you the sharpest image, and a mid point aperture (approximately f/11 or f/13) can be a better option when photographing a row of items such as the ones in this exercise.

I have also learned that DOF seems to be more apparent in the foreground of an image (particularly in this exercise) than in the background.

The motion blur of the woman in the second and third images (who is placing a coin in each of the pots for good luck) is down to a slower shutter speed which was necessary with a smaller aperture, to achieve a good exposure.

For this exercise, I visited Wat Po Temple, Bangkok, where the famous Reclining Buddha is located (see below). My original idea was to use the reclining buddha as my main subject for this exercise, however I found it difficult to clearly see the DOF when I took the three images required, it was not until I walked around the temple, that I found the lines of pots, which proved to be a good subject.

OCA Exercise 2; Focus With a Set Aperture

Camera; Canon EOS 550D

Lens; Canon 50mm prime lens f/1.8

Objective;

Produce three photographs of the same subject at a set aperture from the same viewpoint focusing on a different part of the scene. I used my Canon 50mm prime lens as it is my fastest lens at f/1.8 and I thought this would best suit this particular exercise by giving me good depth of field.

Focal Point: 1^st Ornament

In the first image, the focal plane is on the foreground ornament, which throws the middle and background ornaments out of focus, although the viewer can still identify them.

Focal Point: 2^nd Ornament

In this second image, the focal plane is on the middle ground ornament, thus throwing the foreground and background ornaments out of focus.

Focal Point: 3^rd Ornament

For this third and final image, the focal plane is on the background ornament, throwing the foreground and middle ground ornaments out of focus.

Conclusion;

I originally thought my favourite image would be the first photograph, where the 1^st ornament is the focal point. However on further inspection I have come to the decision that the second image (2^nd ornament) is my favourite. I like the way the out of focus ornaments either side frame the in focus ornament.

My second favourite has to be the first image with the 1^st ornament been in focus and thus the subject of this particular photograph. It grabs the viewers attention before their eyes scan the rest of the image before coming to rest back on the main subject.

I also like the third image, where the 3^rd ornament is the main focal point as the two out of focus ornaments leads the viewers eye towards the main subject at the rear of the photograph.

All of the above images work for different reasons, and depending on the subject and what the photographer is trying to gain from their photograph, would depend on what focal point would be best suited.

OCA Exercise 1; Focal Length & Angle of View

Camera; Canon EOS 550D


Lens; Canon 18-200mm Telephoto Zoom lens f/3.5


Objective:


For this exercise, I was tasked to take three photographs at different focal lengths from the same position to establish my “standard view” when composing an image. I took one photograph at the wide angle, one at the telephoto end and one at standard view.

Standard view: f/4 1/250 18-200mm @ 35mm ISO 100

This is the standard view image which I found to be a similar size to that of my naked eye whilst composing the shot. I found this to be at 35mm (equivalent to 56mm on a full frame camera) on my Canon 18-200mm Telephoto zoom lens. 

                                       Wide Angle View: f/4.5 1/250 18-200mm @ 18mm ISO 100

In this wide angle view, the scene appears smaller in the photograph compared to the real scene as at  wide angle, everything is compressed.

                                       Telephoto View: f/5.6 1/100 18-200mm @ 200mm ISO 100

In the telephoto image above, taken at 200mm, everything seems much larger than to the naked eye. 

To complete this exercise I needed to hold each of the A4 printed images and move them towards or away from my eye until the printed scene appeared the same size as my view of the real scene and establish the distance from my eye;

Standard: Approximately 67cm

Wide Angle: Approximately 101cm

Telephoto View: I held this right up to my face, but could still not focus properly on the image. 

Measurements are approximate as I completed this exercise alone.

Conclusion;

I have learned that the focal length determines the composition, and ultimately the final result of that image. It can sometimes determine the subject of an image by focusing closely on on aspect of an image as shown above in my telephoto view image that focuses closely on a palm tree. 


I have also learned that changing to a longer lens makes the subject appear closer, however this is not the same as moving the camera closer to the subject. 

Neil Barnes - 508523

New OCA Course in Photography

Hi All,

Welcome to my learning log. I recently enrolled on the photography course with the OCA, Photography 1; The Art of Photography.
I received my course work 3 days ago and have so far completed my student profile (which I sent off Friday evening to my tutor) read through the information from the OCA, and started my first exercise       (focal length and angle of view).

I bought my first SLR in 2010 and have read 15 photography books since. I feel I have a good grasp of the basics and have joined this course to improve my overall photography skills, not only technically but also from an artistic point of view.

In the coming weeks and months I will be uploading photos along with my thoughts and what I have learned from the projects and assignments.

Please feel free to comment on my work, good or bad, but please be constructive in your criticism.

Regards

Neil