Cameras, Sensors, and Orchids.

from Mary's Peak Orchid Society/Cherry City Orchid Society Newsletter, "The Oregon Hybrid"

Hi!

I do not know if you folks know me?  I am the guy with the oversized camera with the large flash unit on the front. Some of you might have seen me and thought, I was wandering aimlessly around the Orchid shows the last few years. Actually I have been aiming …at the Orchids.

Since many people have asked me about my camera and photography at these shows, I will try to shed some light (so to speak) on the basics of photography. I will try to remove the misinformation (and therefore the "mystery") about photography, which I have heard at local Orchid meetings and read in the ‘Orchid’s’ magazine. I will also try and clarify the differences between the current cameras and why they “perform” the way they do.

Recently, I was told by a customer that, I was more interested in “ teaching” than she was in “learning”. If that is the case and everyone here just prefers Orchid plant information I will not be offended. I am trying to learn both how to grow Orchids AND do digital Orchid photography although I had a head start in that.

My experience as an artist and photographer for the past 35+ years, and owning a camera business for the past 18 years has given me the experience to help those interested in understanding the basics of photography, and what the different cameras and related gear (you have or are contemplating purchasing) will and will  not do.

In this newsletter I will also cover, if wanted, the specialty of Orchid Photography by having an open dialogue and answering questions you may have about photography and related gear.

Everyone desires information regarding the "Digital Revolution" taking place and how it relates to film! I've discovered from the questions people have asked me, that there is a discrepancy between what they think they are buying and what they are actually getting. Even most of your local camera store salespeople have not been given the information printed here.

First it's important to show and explain the current “formats of film” and “sensor” (digital film) sizes. When you look at the specifications of the new digital “point and shoot” cameras, (cameras that do not have a removable lens) advertisements say they have a 1/ 1.8” sensor, which is completely misleading. And as far as I am concerned a total lie. This is a measurement that relates to a 1950’s way of measuring TV camera tubes. But it does look reasonable in advertising literature. I am inserting a picture here of the actual sensor sizes that are in most consumer and professional (35mm / digital type) cameras out there.

The word “megapixels” means one million pixels or light sensing units, which are embedded in the digital film or “sensor” unit.

The largest sensor size shown is the full, 35mm size which is actually the same as 35mm film or the current 11-14 megapixels cameras. (The price range for digital camera “bodies” in this category is $5000­­—$8000). (Editor’s note, prices are early 2005.)

The next size is the “APS” 6-8 Megapixels (Advance Photo System) film /or sensor size which is smaller than 35 mm film and gives a 1.5 or 1.6 X magnification ratio over 35 mm film. You are “cropping” the center of a 35 mm photo (if you want to look at it that way) for taking Orchid photos. This is great as you are getting a close-up view from the same distance. (Price range: $900—$1800. They do have a problem with “wide angle” photography, however.)  

The next size is the consumer Point and Shoot sensor size and one that gives me no end of irritation. The current (this week) “megapixel” amounts are approximately 1-9 megapixels.  There are 300—400 different camera models coming out every 6 months and the prices are dropping at the same rate. (Price range: $200—$1000).

If you are considering buying or have a point and shoot type camera and you look at the zoom lens (a typical number is 7.2-28.8) which as stated is equal to 35-140mm in 35 mm, and do the math (divide 7.2 into 35) you will get 4.86. So it is a little less than 1/20 the size of 35 mm film. This also means that the lens used would need to be 20 times sharper than a 35 mm lens.

 It is important to understand the way "the sensor” is made. It is made up of 4 layers to record the different colors. There is also the issue of the angle at which the light hits the sensor. The sensor has “wells that are 4 layers (colors) deep so a “wide angle lens" means that the light rays hitting the sensor are doing so at a shallow or narrow angle and then would have to change direction and go straight down into the sensor well. The cartoon here is… if you think of a big SUV trying to turn a very tight corner and it clips the cement that is sticking out, that causes a lot of “noise”. That is what happens when the light rays try to turn and go “straight” into the wells. That noise makes it not sharp when it is enlarged.

Another problem is the.....”DIGITAL ZOOM!” Do not use it! It is taking a smaller area of the tiny chip and electronically enlarging that area which is magnifying those tiny pixels. I have been asked why my pictures are sharper than point and shoot digital cameras, which have an equal, or near “megapixel” number. The issues I've covered here are just a few of the reasons.

Another question I am asked is “How close to the subject will it focus”? The actual question should be: "What is the largest image size (ratio) at the closest focusing distance? Besides the issue of distortion you probably have seen the guy in the commercials that walks real close to the lens and his nose gets really big? That is wide-angle distortion! This is why you want the “macro focusing capability” to be on the telephoto (higher number) end of the “zoom” range. You will have more “working distance” and less distortion to say nothing of working in your own light.       

If you are taking a photo of a large Orchid such as a Cattelya you can do this fairly easily But if you have a small Pleurothallis, that is a whole other area of photography which needs explanation in order to get sharp, in-focus photos.  There are a number of ways to do close up photography and the results vary with the equipment and the way it is used.

Most cameras advertising now states, the “Close focus distance.” Not the actual image area (or size) at the “closest distance.” A true macro lens (not a zoom that has “macro capabilities”) which has a 1:1 image ratio means, that if you photograph a dime at 1:1, it’s image will appear on film (or the sensor) exactly the same size as it is in life before it is enlarged. To get it "larger than life" or greater than 1:1 on the film/sensor is a whole different set of issues.

I would be happy to answer further questions about photography or photographing your plants and the necessary gear. You can email your questions to:

I hope this has been helpful!

Thanks

Dick McRill