Blog #42 It's All in the Details

December 05, 2016  •  Leave a Comment

Blog #42 It’s All in the Details. 

Images can be presented in many ways.  We are all familiar with common ways that images are displayed.  Paper prints such as in books or frames on the wall, projection onto a screen, and LCD screens such as a laptops or smartphones are the most common for viewing images.  Detail in an image is an important and controversial topic. Film and digital photography differ in their approach to detail within the image.  This week’s blog piece will address the concept of detail in the two dimensional image, albeit in a brief manner with an emphasis on the final printed image. The proverbial devil is in the details.

In the last decade or so, and especially the last few years, film photography, digital, and even smartphones have come to produce similarly good quality images.  There are no bad cameras anymore. When viewed on a 13” screen (laptop) or 4.5” screen (smartphone) there is no discernible difference detectable in the image quality of just about any image taken by any camera. Our eyes can only see up to about 300dpi and detect differences in images up to about 600 dpi only so anything more than is sort of overkill. There are serious professional forums and online discussions about this topic for the scientifically inclined reader. 

Let’s start with film.  Film photography under went many changes in it’s humble beginnings.  Paper and chemistry were crude and the task of fixing light onto a surface was a messy process at best.  After some trial and error and many decades, photography made some significant advancements.  Chemistry and paper had come a long way and in the early 20th century, images started to look very good and retain archival quality.  Many printed images have survived 100 years or more without fading much or completely disintegrating. 

There are many different sized negatives: 35mm, medium format, 4x5 (inches), large format which is around 8x10 and others. In general, the common and widely available 35mm size can make acceptable prints in the 8x10 size to the 11x14 size.  It is possible to make acceptable prints from a 35mm negative that are 16x20 in size but there could be some image degradation.  The details and quality of an image is a combination of many variables.  The camera, lens, lighting, film, and developing, are all variables that effect the final quality of the negative.  For images 16x20 and larger, you would be wise to use a medium format negative or larger to be on the safe side.  Of course the final print size is determined by the intended size of the print as determined by the artist, the quality of the image (negative) and the photographer’s tolerance of the grain in the given image. Medium format film is almost three images larger than 35mm. See the illustration for six comparison below. 

Grain or resolution (expressed in units called dots per inch or pixels per inch) as well as the distance at which an image is viewed are significant factors in the overall success of how the image is displayed and presented.  A general rule of thumb is as follows. The viewing distance should be around twice the diagonal of the image. For example let’s say that we have a print that is 8x10.  That’s rectangle vertical or horizontal. There is a diagonal line that can be drawn to make two triangles within the rectangle. This is the measurement that we are interested in. 

This formula will apply to the image rather than the paper size. Many images are printed with a matte around it or a border, ignore that for the purposes of this point. The hypotenuse “c” of this picture is the square root of a squared times b squared since the length of the two sides, a and b, is known.  Sound familiar? That’s because you learned this in primary school and it’s known as the Pythagorean Theorem.  Thanks Pythagorus! Now, just multiply the result by two and you have the proper viewing distance for your image. This formula will work for proportionally larger images. 

If viewed closer than this “Goldie Locks” viewing range for optimal quality, the image may become blurry or deteriorate.  Chuck Close is a brilliant artist and painter who more or less illustrates this concept through painting large portraits using a pixel-style in his work that, when viewed as a far enough distance, you can see the person but up close, his work just looks like a bunch of coloured squares.  

Figure 1.  An 8” x 10” image (without matte or borders) has a diagonal (hypotenuse) of 12.81”.  Multiply 12.81 x 2 to get 25.62” or the proper viewing distance of this photograph.  Viewed closer, and the grain or resolution (quality) of the image may start to deteriorate and degrade.  Quality might be lost with this viewing range. 

With regard to digital files, in general the more megapixels the larger size the image can be printed without loosing image quality.  RAW images contain all of the information captured by the sensor and can are therefore more malleable in post-processing.  JPEG images are compressed and tend to be less forgiving when post-processing adjustments are applied.  TIFF files can be manipulated from RAW files and are uncompressed. Use TIFF files when enlarging prints for maximum detail retention.  

The images shown come from four different sources.  One is from an iPhone 7+, 35mm film, 120 medium format film, and one digital JPEG from a Fujifilm X-T1 16mp mirrorless camera. Without looking at the labels. can you guess which is which? They will be displayed at the end of the blog post with labels for identification purposes.  You can try prints of different sizes to experiment with optimum viewing options for your printed images.  

“A photograph doesn’t exist until it is printed”, according to Constantine Manos. Indeed, a printed image is a real thing whereas an image on a screen will fade as with the day and become lost in the sea as sands on the beach.   

 

The light is always right.

 

jhg

 

 

 


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