As my first exercise and given the activities required I've decided to take my position on my front drive and take an image across toward Eastbach Airfield.
This first image I've taken using a 28-105mm zoom lens. I've adjusted the lens focal length so I can get as near to having the image in my view finder that matches that I can see with my eye. This lens is attached to my Nikon D700 camera which is regraded as a full frame camera (full size sensor) as opposed to a crop sensor.
In this exercise I found that a lens focal length of 78mm best matched that of my eye. This image I've converted to a jpeg and resized it with a maximum length of 10 inches ready for my A4 print and resized to around 300kb to help with file downloads when viewing my blog. If anyone is able to recommend anything better that they use then please contact me via the blog, thanks.
Image 1: Focal Length at 78mm so that view finder view matches what my eye would naturally see. I've kept the the 4 foot metal railed fence in the image to give a sense of scale to those viewing my blog and looking at the images
Its a bright sunny day and clearly I've over exposed the sky. This is a great example why landscape photographers will often shoot in the golden hours and dawn and dusk since the sensor is unable to correctly expose both landscape and sky correctly. Having printed. I've printed this off at a4 size and gone back to my spot (advantages of using my drive as the camera position) and held the print. I'm holding this around 10 inches in front of my eyes so that the image on the paper matches that seen by eyes. I'm not sure what this distance means, perhaps its related to the distance between me and the subject of shooting and the focal length of the camera
Whilst the image captures a portion, say centre section of what I can see the camera clearly cant match the total view of what my eyes see, in a single image.
Image 2: Focal length at lens zoom maximum of 105mm
As the lens has "zoomed in" on the hill its clearly made it appear bigger in the frame. I am of course expecting to have to hold the A4 print further away from me so that the print matches the scene from my original camera standing position. Lets see...... well lucky I have long arms and I'm almost at full arms reach at about 20 or so inches holding the A4 print away until the image matches that seen by my eyes. Good job my lens is max'd out at 105mm as my arms would not be long enough to hold the A4 print far enough away for it to match the view my eyes would see.
Image 3: Focal length at lens zoom maximum of 28mm
The image is now at a wider view and I note in this image the sensor is better able to automatically the overall image exposure, which is unsurprising as this and the other images are almost shot into the sun as the shadow from the lamp post suggests the angle of the sun to my position. You will note I have a lens flare in centre top of the image however for this exercise I'm focused entirely on the learning element rather than any clone stamping adjustments. So before I go back out with the A4 print of this image I'm expecting the print to be brought much closer to my eyes....yep its 3-4 inches. With the wider view I can notice when comparing the image to my eyes' view there is a slightly bending of the image. This I know to be convergence of the car's body lines. Not noticeable to the viewer of this blog but it is when comparing my view to that captured by the lens. I also note at this wide view distance of subject has increased and elemnts visible in images 1 & 2, such as the basketball hoop backboard, is now no longer in view
Exercise Learning's
So what have I learnt, key elements as I see and understand them:
a) a camera sensor using a lens at a focal length matching the view finder subject distance with that my eye sees does not maintain the angle of view my eyes can see. This is often why those great views seen on holidays and tourist destinations cannot be captured the way we saw them. This can lead to disappointment if this isn't understood in advance
b) Using a longer focal length will result in a narrow field of view; there is also a compression of distance
c) Using a small focal length will result in a wider view, there can be an exaggeration of distance and there can be a creation of converging lines. In my final image the viewer may not see it but in Image 3 but when compared to my eye view line convergence is there along the lines of the car bodies.
d) Shooting into the sun with a wider lens the sensor appears better able to handle the dynamic range however I suspect this is simply down to, in this series of images, less greenery in the final image and less dynamic range that the sensor is attempting to capture. This is proven when view the histogram for each image, the first and second image show right hand highlight clipping, hence the over exposed sky. The 3rd image is able to reflect the light blues my eyes see but were not captured in images 1 & 2
e) Image exposure may need to be adjusted subject to the sensor captured scene based on lens focal length. However for this set of images I've kept it simple to focus on the exercise.
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