These color photographs are produced using the three primary colors, red, green, and blue determined by the Bayer filter.

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Therefore the number of possible choices, for each pixel, in a small 8-bit file is 256^3 power, or 256*256*256 which equals 16,777,216.

A pixel can only display a single color, including black, white, greyscale, and RGB Color values. The color of each pixel is determined by the amount & kind of light information it collects.

In some shooting scenarios such as star, Milky Way & night sky photography, the light levels are so low that the image noise will be very high. Even the best camera sensor for low light, such as models made by Sony, still produce some noise.

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Understanding camera sensor size and why it actually matters is one of the most important aspects of learning photography.

I used autofocus most of the time. I did notice some differences here. The EF100 is a bit slower and sometimes had trouble to focus very closely and kept moving back and forth a little bit. This was in particular a problem when there was some wind. The EF could not keep up with the changes in distance due to the wind. The RF did a much better job.

ISO determines the amplification the light information receives as it’s conveyed into the digital world, where it’s stored on a memory card as a picture file.

When a pixel well fills to the top with electrons, creating the maximum signal, it’s corresponding tonal value is white, producing a white pixel in the photo.

For example, the number of possible choices for a 3-bit system is found by using the binary base 2 and raising it to the power of 3,  2^3 = 8.

Consider this like a child that only speaks two words, yes & no, black & white. You wouldn’t depend on this child to communicate a landscape scene with a large degree of accuracy or precision.

So, even though it is a lot of money for a dedicated lens, I decided to buy the Canon RF 100mm F/2.8L Macro IS USM, as its full name is. Now I have to relearn a lot of stuff.

The graphic below shows an 8-bit system with 256 or ( 2^8 ) different bins. Due to the vast number of possible tonal choices the transition from one to the next isn’t discernible to the human eye. A JPEG image is 8-bit.

Magnification: The RF100 has maximum magnification of 1.4, while the EF100 has a magnification of 1. That is a considerable difference. On APS-C cameras these become 2.24 and 1.6, respectively.

Camera sensor size is the most important factor in determining overall camera performance & image quality, given the optimal focus, f-stop, ISO, and shutter speed settings have already been obtained.

Smaller camera sensors such as a standard 22.3mm width, APS-C Sensor ( see graphic above ), would have a crop factor of approximately 1.6.

Physical sensor sizes are provided in terms of width and height, usually in millimeters. A standard sensor size such as 36mm × 24 mm is known as a full frame 35mm format camera.

When photons collide or interact with certain materials, such as silicon CMOS image sensors, free electrons are released from the sensor material, producing a small electric charge. This is known as the Photoelectric effect.

You can use the DoF preview button on the front of the camera to see the actual depth of field. However, this unfortunately does not work with autofocus. With manual focus though, it works great. Even the focus guide works while holding that button.

For example, although a crop sensor usually provides less quality & detail than a full frame sensor, a crop sensor from 2017 would most likely provide more quality and detail than a full frame sensor from the year 2000.

This is a scientific fact, there is no dispute. Sony makes better sensors than Canon for landscape and outdoor photography.

When the incorrect camera settings are selected, the squares on the pixel grid don’t match the squares image grid, producing a digital image that doesn’t match the scene being photographed.

Each photographer has different sensor size requirements to produce the images they desire. I’m not going to tell you what camera to buy, but will provide some of my personal favorites.

Image stabilization. Because I use flash all the time, image stabilization is not important to avoid camera motion blur. But it does help to get a more stable image in the viewfinder and to focus more easily.

Camera sensor

Think of a sensor like the sail on a boat. The larger the sail, the greater the surface area, the more wind it will catch.

As the ISO becomes larger less overall light (signal) is required to produce the same tonal value. As the ISO increases the noise levels are amplified creating more overall noise in the image.

When a pixel well contains no electrons it produces no signal.  The corresponding tonal value is a black, producing a black pixel in the photo.

For example, the diagonal distance or hypotenuse of the 36mm by 24mm full frame can be found as follows: =SQRT((24^2)+(36^2)). The outcome is approximately 43.3mm.

PRO TIP: If you really enjoy photography buy the best camera you can afford. Then you don’t have to upgrade multiple times over the coming years. It saves money in the end. I know from experience…

The photographer’s goal is to select the correct camera settings relaying this information with precision & accuracy, producing a digital image that matches what they see through the viewfinder.

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Humans perceive green as the brightest, red as the second brightest, and blue as the darkest, out of the three primary colors. This perception of color brightness, known as lightness or luminosity, is only a function of the eye’s physiology. Remember the Bayer Filter!

Both of these lenses have a maximal aperture of 2.8, which is much wider than the kit lens I used before. Because the camera focuses with the lens wide open, the depth of field you see during focusing is very small, and considerably smaller than with the kit lens. Initially I thought that the focus of these lenses was worse, but that was obviously not the case. When taking the shot, the actual aperture is used, giving the expected depth of field. After a bit of practice this was actually a positive. Because only a small area is in focus while focusing, you have to be very precise, leading to better shots.

CMOS camera sensors and pixels inherently produce a small amount of noise. This is similar to radio static heard at low volumes in headphones. Even the best cameras with the optimal settings create small amounts of noise.

The free electrons are collected and counted by individual pixels on the sensor grid.  Each pixel well has a maximum capacity of electrons it can collect. This maximum is known as full well capacity.

I am a landscape & outdoor photographer. I don’t shoot weddings, for clients or do product work. Therefore I can’t recommend cameras that I haven’t personally tested.

When adding the adapter to the EF100, both lenses have about the same length and weight. The RF100 clearly looks more modern. It displays all information in the camera, not on the lens. In particular, when using manual focus, the RF100 shows the focus distance and the magnification factor in the viewfinder, while the EF100 does not. For the EF100 this can be a problem because there is no tactile feedback on the position of the focus ring. So while looking through the viewfinder you do not know whether you are at maximal magnification.

No matter the camera, higher ISO values will always produce more overall noise and less overall dynamic range in the final RAW file.

Because of the hassle to use them, I think I will never use the extension tubes in the field. I might use the Raynox in certain rare situations where I need more magnification and can hold the camera against something solid. In a studio setting, I might use the combination to get maximal magnification, probably while using focus stacking.

Each pixel is covered with a color filter, either red, green or blue. The color of each pixel is determined by the color of light (frequency of light wave) which passes through this filter.

As shown in the graphic below, a 1-bit system can only communicate black and white. A 2-bit system can communicate black, white and two tones of gray.

Non-extending. I don’t like lenses that extend when focusing. I use a flash diffuser on the lens and when the lens moves, that diffuser moves as well and might bump into the plant with the insect. Also, I sometimes rest the front of the lens on something.

Digital cameras can be broken up into 3 different categories for sensor sizes, largest to smallest respectively, Medium Format, Full Frame, and Crop.

On the web, the opinions about this differ. Focus shift definitely happens in the RF100 (more than in the EF100) but does it effect your images? When narrowing the aperture also the depth of field increases. Some field test by others do not seem to show any problem. But to be sure I did my own tests. Here is one of the resulting images I produced:

At the left you see the numbers for the maximal magnification, achieved at the minimal focus distance. They show the width of the minimal area that can be photographed (in cm), the working distance where this is achieved (in cm) and the corresponding magnification factor. (This is all for an APS-C sensor.) At the right you get the maximal width possible, the corresponding distance and magnification factor. When just using the lens you can focus at infinity, so this is no useful information.

NOTE: Not all cameras process color the same way. The following example allows you to conceptualize this concept. It’s not meant to be technically accurate for a specific camera.

For the EF100 you can easily get a good used one for less than 700 euro, while the RF100 costs 1500 euro (used ones are not really available yet). So there is quite a price difference. Is that worth it?

Due to the higher performance, especially in low light, and lower cost the CMOS Sensor is found in nearly all modern digital cameras.

Electrons counts can’t determine specific color information, therefore, a color filter is placed over each pixel helping to determine it’s color. This is discussed in detail below.

But you buy a lens for the coming 10 years. And I am afraid that at some moment I am going to want the improved sharpness and autofocus and the extra magnification. Also, lenses with RF mounts are the future, so the EF100 will lose its value pretty quickly, while the RF100 will be valuable for a long time to come.

In terms of color & tone, machines have bypassed the precision that the human eye, engineered by trial and error, through millions of years of evolution, can discern.

Mega is the mathematical term denoting 10^6 also stated as “10 to the 6th power” which can be written as 1,000,000 or 1 million.

Disclaimer: This is not a full review of the lenses. There are many of these on the web. I only look at the lenses from my personal perspective and for insect photography, in particular handheld. Macro lenses are often also used for portrait photography, product photography, and even as general prime lenses. Moreover, I use them on a modern APS-C camera, which might be different than on other cameras.

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Doing some pixel peeping on controlled shots, for both lenses sharpness is very good until F11. F16 is still doable, but F22 is not good enough, especially if you are going to use digital crop. I had the feeling that the RF100 was slightly sharper than the EF100 at F11, but this can be due to many aspects other than the lens.

This charge is used to transfer the light information, collected by each pixel, into digital information which cameras & computers can understand.

It shows the RF100 lens at around 1x magnification, autofocusing on the 10 cm mark on a ruler. The ruler is at an angle of 45 degrees with the camera. From left to right the camera uses F2.8, F4, F5.6, F8. F11, and F16. ISO is 100 and shutter speed determined by the camera. No flash.

None of the information the pixel collected prior to filling can be recovered or used in the final image. It’s gone forever!

There is a much smaller difference between the APS-H vs APS-C. These cameras will produce close to the same image quality, with slight variations.

The EF100 is a bit more noisy than the RF100. You clearly hear the autofocus and also the image stabilizer. I find this a bit annoying but I guess you get used to it. At least you know the lens is working for you. The RF100 is almost completely silent.

The camera sensor, also known as an image sensor, is an electronic device that collects light information, consisting of color & intensity after it passes through the lens opening, known as the aperture.

JPEG files are usually 8-bit whereas RAW files are usually 12 to 16 bit. Some cameras have the ability to change their current bit rating through user defined settings.

Most, but not all, CMOS sensors use a Bayer Filter which looks like a quilt of Red, Green, and Blue screens, with a single color screen covering each pixel as shown in the graphic.

The example below shows the tonal values of black to white communicated with varying degrees of precision, by different bit depth systems.

Each tonal value, on the scale of black to white, has a corresponding signal required to produce it. Specific signal levels produce specific tonal values. The more electrons a pixel collects the stronger the signal it creates.

What got me a bit worried about the RF100 were reports about focus shift. The Canon cameras (like most mirrorless cameras) use the widest aperture (F2.8 in this case) when focusing and only when you shoot the image the aperture is closed to what you set it to. Focus shift means that when the aperture becomes narrower (F number becomes higher) the plane of focus shifts a bit. This could mean that in the actual image, the point you were focusing on is no longer perfect in focus. This would be a serious issue as I often use F13 or F16 when shooting insects.

Each individual square pixel represents a small sample of the image composition as a whole, consisting of a single color. No more.

Bit depth specifies the number of unique color & tonal choices that are available to create an image. These color choices are denoted using a combination of zeros and ones, known as bits, which form binary code.

Each electron produced during the Photon sensor collision carries a small electric charge. The more electrons a pixel collects, the more charge the pixel well contains. Electric charge is a physical measured value.

The “rainbow colored” rectangle on the graphic shows the sensor grid. Pixels are so small that it’s hard to see each individual unit.

The red channel can display 255 different variations of red, the green can display 255 variations of green and the blue, 255 variations of blue.

Excellent central image quality. As I use an APS-C camera, image quality in the corners is not important, as the corners do not show in the image. But, because of the high 32MP resolution in the area in the center, excellent central image quality is essential.

As the bit depth of the system increases the degree of precision which information is communicated from the real world into the digital world also increases.

Mark Overmars is a dedicated insect photographer that loves to share and regularly publishes about his work and about photography in general. You can visit his website at www.insectphotography.org. Download his free insect photography book at www.insectphotography.org/book.

CMOSsensor

The ISO determines the amplification of the signal & inherent noise. The ISO also determines how much light is required for optimal exposure.

We have surpassed the 2-year-old child that can barely speak, we have surpassed the adult with a vivid and detailed vocabulary, we have arrived at a degree of precision that only machines can record and communicate.

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Total Color Choices Per Pixel = 16*16*16 or 16^3 which equals 4096 total choices. 16 represents the number of color choices per channel. There are 3 primary color channels.

Larger physical sensor sizes combined with larger megapixel counts provide increased camera performance, with less noise, especially in low-light shooting situations.

When the correct camera settings, shutter speed, ISO and f-stop, are selected, each pixel on the sensor grid will collect & record the exact color of the corresponding square on the image grid.

Becoming a histogram expert is critical to understanding why camera sensor size matters, in turn producing the best image quality.

Larger sensor widths yield larger sensor surface areas providing more area for the capture of light information over a standard interval, known as exposure time.

The best way to improve quickly is by learning firsthand from someone that’s optimized their skills, over a decade or more through trial and error.

The 3 & 4 bit systems provide a larger selection of choices used to communicate varying tonal values within the tonal range.

TECHNICAL NOTE: Although each of the color channels have the same amount of steps, the variation of green can still be seen all the way down to 1, where it’s hard to tell any difference in red at 1, and blue drops off at 2.

Sony currently produces some of the highest dynamic range sensors on the market for full frame cameras. These camera sensors are rated at approximately 14.8 stops. Many Nikon cameras use Sony sensors due to this fact.

Pretend the following graphics are the real world scenes that you’re seeing through the camera viewfinder or on the back of your camera live view screen.

The example below shows the 4-bit color scale for RGB Primary colors red, green and blue. Bin 15 in each of the color channels is pure fully saturated color, also known as hue.

Imagine an image composition, seen through a camera viewfinder, with an imaginary overlaid grid, containing millions of tiny uniformly sized squares, as seen in the graphic below.

An adapted version of this article has appeared in my free book My Journey into Insect Photography that you can download here.

After using my kit lens and extension tubes for two months it is time to get a true macro lens. Here I talk about my requirements and compare the new Canon RF 100mm 2.8L Macro with its much cheaper predecessor, the EF 100mm 2.8L Macro. Which one should I buy?

After the exposure time, defined by shutter speed, has elapsed, the signal information produced by each pixel is processed & converted into a digital language known as binary code.

That being said, I’m happy to recommend a few different camera models for landscape & nature photographers. These may not be specific to you, but they can help in cutting down decision fatigue. They may also work for other niches of photography, but I can’t guarantee it:)

Working distance: At 1x1 magnification, both are above 10 cm. The RF100 has a working distance of 9 cm at 1.4 magnification.

By gaining an understanding of how camera sensors actually work, and experimenting on your own, is the best way to figure out which camera and sensor size best fits your needs.

The number of electrons collected by each pixel well produces a corresponding tonal value for that pixel. This tonal value is displayed in the final photo, along with the color.

Smaller pixel pitch (width),  combined with larger sensor size, and the latest software & hardware, will produce the best image quality.

CMOS Sensors are defined by their physical size ( surface area for capturing light information ) and the number of light information collecting pixels which make up this surface area.

Dynamic Range is defined as the difference or range between the strongest undistorted signal (brightest tonal value) & the weakest undistorted signal (darkest tonal value) captured by an image sensor, in a single photo.

Camera sensorstructure

Digital photography is the process of recording real world color and tones, from a scene or composition, using individual pixels.

I think Sony makes great low-end models with great sensors. Their high end models have fantastic sensors but are plastic and cheaply made. I prefer Nikon at the high end, with metal bodies, and the same Sony sensors. This is my personal preference.

For diagonal distance think of a straight line from the top right corner to bottom left corner. This is also known as the hypotenuse.

A digital camera uses an array of millions of tiny light cavities or "photosites" to record an image.

Take a look at different objects around you. If you look closely, under a large amount of magnification, everything becomes a single color on a very small scale.

Image stabilization seems to work well in both cameras, but it is clearly audible on the EF100 while being almost completely silent on the RF100.

In the field I noticed I do not really use the maximal magnification. When photographing handheld this is almost impossible, unless there is absolutely no wind. And even then the depth of field becomes so small it is better to use a smaller magnification and a digital crop later. So the advantage of the RF100 is not really important here.

High-speed autofocus. Contrary to the belief of many macro photographers, I use autofocus most of the time. But for this to work smoothly, the autofocus has to be very fast and precise. So no manual lens for me.

Sensorformat

NOTE: This image was captured before twilight, in the pouring rain, on the Li River in China. This shooting scenario is the ultimate test for a camera sensor.

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Canon continues to produce their own sensors which significantly lack in dynamic range, comparatively, rated at approximately 11.8 stops for their top model cameras. They also produce a much larger amount of noise at high ISO values.

The tonal values produced by each signal are combined with collected color information to produce each pixel’s final color within the photo.

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The goal is to fill each pixel well to it’s corresponding tonal value maximum without clipping or losing data off the top end, thus increasing the Signal to Noise Ratio and image quality.

The precision and accuracy which this information is communicated and displayed in the final image is determined by the bit depth.

Red light passes through the red filtered pixels, while green and blue light do not. Blue light passes through the blue filtered pixels, while red and green light do not. You get the gist…

Since color information can’t be determined directly by the number of electrons in each pixel well, a color filter is placed over each pixel.

At least 1x1 magnification. I like to shoot small insects. With my current setup they still tend to become too small in the image and require a large digital crop. A 1x1 magnification of the lens is actually 1.6 for my APS-C sensor, so that is already very good. Anything more is a bonus.

The human eye, the second most (known) complex object on the planet, after the brain, has no problem discerning approximately 12 million different colors.

As can be seen the maximal magnification with just the macro lens is 2.25, as was to be expected from the specs. Adding extension tubes or the Raynox have a similar effect, but extension tubes allow you to stay further from your subject. Using both gives an amazing 5.14 magnification factor, but this is very hard to work with.

Selecting the best overall camera settings (ISO, shutter speed, f-stop) and image quality attributes (dynamic range, noise, bit-depth, sensor size) is impossible without a basic understanding of how a camera sensor works.

There are two popular types of image sensors, CMOS sensors (complementary metal-oxide semiconductor) & CCD sensors (charge-coupled device).

As a sensor collects more light, producing a larger signal, less overall noise is seen in the final image. The Signal to Noise Ratio (SNR or S/N) is used to describe the phenomena.

The RF100 is the better lens. It has more magnification, has better autofocus, seems slightly sharper, and is more modern. But are the improvements worth the large price difference? This is a difficult one. Buying the EF100 would be a considerable improvement over my current setup, and I would be happy with it. The slower autofocus would be the only thing that worries me a bit.

That’s almost 17 million different possible choices for every single pixel. There are millions of pixels on each sensor! This is a small JPEG file that the worst modern digital cameras can capture.

In the graphic below, the pixel wells on the left have lower signal to noise ratios where the pixel wells moving towards the right have higher signal to noise ratios.

They both see and collect the same real world information, but one can describe it in vivid detail, while the other cannot.

When making the following comparisons of image sensors, assume that each sensor compared is from the same fabrication year.

Still I wanted to know what could be achieved. So I did some tests to determine the magnification, together with the working distance (from the lens) where this is achieved. I looked at the lens itself, the lens with 31 mm of extension tubes, the lens with the Raynox 250, and using both the extension tubes and the Raynox. Here are the results for the RF100.

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The bit depth determines how many steps or possible choices within the tonal range can be communicated. Each step or possible choice is known as a bin. The more bins the more choices.

Images that contain larger proportions of lighter tonal values will have higher Signal to Noise Ratios revealing less visible noise.

Digital photography is the process of recording real world color information represented by the image grid, and relaying it into the digital world represented by the pixel grid.

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The number of electrons each pixel well collects determines it’s brightness, also known as value, on a scale of black to white. The scale of black to white is known as the tonal range or tonal scale.

Reasonable working distance. With my current setup I sometimes have to get as close as 3 cm from the lens to the insect. That can scare the insect away, and I often bump into things with the camera and diffuser. So I want a lens with a longer focal length, like 85 mm or 100 mm, to get a reasonable working distance.

In photography, the number of bits determines the possibilities of color or tone a single pixel can display, known as bit depth.

Noise is dependent of camera make and model as well as settings. Different types of noise makeup the overall noise profile for a given image.

For example, Red ( 12 ), Blue ( 6 ), Green ( 15 ) would create unique color and Red ( 1 ), Blue ( 2 ), Green ( 4 ) would create another unique color.

The aperture diameter & shutter speed control how much light is captured by each pixel, thus increasing or decreasing the signal strength.

Notice the massive difference in light collecting surface area between the APS-C vs full frame camera sensors. These cameras will produce much different overall image quality, with the larger far exceeding the smaller.

The 2-year-old child, seeing the same thing, has a hard time describing the scene accurately, having a limited vocabulary.

Using this information, and a series of algorithms & interpolations, the camera can determine the color of each pixel contained on the sensor grid.

An adult and a 2-year-old child looking at the same landscape see close to the same thing, consisting of color and tonal values (light intensity).

As you expect, the depth of field increases when the aperture gets narrower. I think that in all images the 10 cm mark is perfectly focused. However, if you look carefully you notice that the depth of field extends more to the back than to the front. I don’t know whether this is the result of focus shift. But my conclusion is that focus shift is not a serious problem for macro photography, even when using apertures like 11 or 16.

The crop factor is a dimensionless reference number, associated with image sensors.  It compares the diagonal distance across each specific camera sensor to the diagonal distance across the full frame camera sensor.

The RF100 has this weird Spherical Aberration control, which seems useless for insect photography. Who wants dreamy looking insects? So I set it to 0, with the lock on. It also has the extra control ring that all RF lenses have. That can be handy. I normally set this to exposure compensation. But as I use flash for the insect shots, that is rarely used there.

Images that contain larger proportions of dark tonal values will inherently have lower Signal to Noise Ratios revealing more visible noise. This is one reason low light and night sky images contain so much noise.

Each pixel can only collect the primary color information of it’s assigned red, green or blue filter, along with the number of electrons collected in the pixel well, which determine tonal value.

For example, a camera with high dynamic range capability could shoot directly into the bright sunlight & still collect information from dark shadow regions, without producing much noise. This is shown in the video above.

The 14-bit file contains 2^14th power of possible variations for each of the 3 color channels. That’s 16,384 possible choices per color channel.

The pixel specific tonal value is determined from the number of electrons ( charge ) collected and the color is determined using the Bayer Filter.

Active amateur photographer with a passion for insect photography. Author of My Journey into Insect Photography. Website: www.insectphotography.org.

Light is made of photons or small packets for carrying light information. Photons are elementary particles which have no weight but carry information about light.

It only means that each generation of camera will get slightly better in the areas noted above, as software, hardware, and engineering improves.

To the human eye, the perceived brightness of green is greater than that of red or blue, thus green filtered pixels are represented twice as often in the Bayer Filter.

I went out for three days, taking insect pictures with both lenses at different locations. Using the lenses was easy. Actually easier than using my kit lens as I no longer had to set the focal length. The weight of the lenses was something to get used to, but soon I no longer noticed. They are not too heavy and give a solid feel while taking shots.

Understanding CMOS imagesensor

The digital language takes the form of zeros and ones ( bits ) & communicates the values of color ( Red, Green, Blue ) & tone collected by each pixel.

Due to this fact, slightly overexposing images, known as Expose to the Right or ETTR , provides higher Signal to Noise Ratios and overall better image quality, provided that the brightest pixels are not “clipped” or “blown out”.

The combination of the following, provide a reasonable estimate of a camera’s image quality. They are discussed in further detail below.

Both have image stabilization, are non-extending, and have a similar weight of around 700 gram (if you add the weight of the adapter to the EF100), which is on the high side.

That basically leaves the Canon and Sigma lenses. The Sigma 75 mm has a minimal working distance of only 6.5 cm, which is a bit small. So the 105 mm might be a better choice. Both Sigma lenses are considerably cheaper but reviews say that they are slightly less sharp and the autofocus is less good. So instead I decided to rent and test the two possible Canon macro lenses: the Canon RF 100mm 2.8L Macro and its predecessor, the EF 100mm 2.8L Macro using an adapter, which I now abbreviate as RF100 and EF100.

My requirements limit the possible choices considerably. Having autofocus rules out all the great Laowa lenses and many others because they are manual. B.t.w., an addition problem with fully manual lenses is that the excellent manual focus guide of Canon cameras no longer works.

Unlike megapixel counts, having a larger dynamic range is always a positive camera attribute. Dynamic range is provided in stops, which is a measure of light.  For each stop increase the amount of light information collected doubles.

In turn, a digital image is produced, from millions of pixels, which matches the real world composition seen through the viewfinder.

I was a bit disappointed with my keep rate for both lenses. But then I realized that with these lenses I was using a larger magnification than with my previous kit lens. And that considerably reduces the depth of field and, hence, the chance of a sharp image at the correct place. I learned that it is often better to go for a bit of digital crop to get a better depth of field.

This is very difficult to compare because I took different shots with the cameras. (I did not want to switch lenses too often.) In general, the quality was better than the shots I took before with the kit lens and extension tubes. For my earlier shots I often needed to do some sharpening in post processing to get them sharp enough. With the new lenses this is no longer necessary.

Along with the number of pixels, sensors are also rated in terms of physical sensor size or surface area.  The sensor surface area also determines the size of each pixel.

There are some other features that are less important to me. For example, both are weather sealed, but I don’t like photographing in the rain, and insects are normally invisible in wet, cold, and/or stormy weather.

The precision of the communication is rated on the scale of bit depth. Larger bit depth systems allow more precision in describing the information collected by each pixel.

For the following example, assume the latest pro model full frame camera from Nikon or Sony. The exact model does not matter.