• Andy’s E-BOOK — Photography Travel Guides

  • PLEASE RESPECT COPYRIGHTS!!

    All Images and writing on this blog are copyrighted by Andy Richards. All rights are reserved. You may not, without my express, written permission, download, right click, or otherwise copy my images for any reason. Copying an image and putting it on your blog, website, or even as a screensaver on your computer is a breach of copyright, EVEN IF YOU ATTRIBUTE THE SOURCE! Please do not do so.
  • On This Blog:

  • Categories

  • Andy’s Photography Galleries

    Click Here To See My Gallery of Photographic Images

    LightCentric Photography

  • Andy's Flickr Photos

  • Prior Posts

  • Posts By Date

    December 2018
    M T W T F S S
    « Nov    
     12
    3456789
    10111213141516
    17181920212223
    24252627282930
    31  
  • Advertisements

Is Digital Capture Too Easy?

Do We Take Digital Capture For Granted?

In the “My Story” page on this Blog, I suggest that it would be a wonderful exercise for “new” photographers to begin with a truly all-manual camera and color transparency (“slide”) film.  Perhaps there are readers here who don’t even know what that is (or was).


For many photographers – particularly nature and outdoor photographers – a process called color transparency film, became the medium of choice

The “brave new world that digital “capture” has given us has also done a pretty good job of hiding the technical aspects behind the curtain (no pun intended).  To understand that statement probably requires a little trip down memory lane.  The original idea, of course was chemical reaction caused by exposure to light (hence, “exposure”) light on a medium. The reaction caused the chemical to change color (or at least contrast).  While there were some prior experiments, the first “permanent” photographic image was probably the Daguerrotype, in the 18th Century.  Over time, the chemical medium of choice became silver nitrate crystals, suspended in an gel-type emulsion which we called “film.”  A series of red, green and blue layers were later added to the process, to create “color” images.  Compared to the vivid color we see on our computer screens today, early color film was rather subdued.

Black and white, and later, “color reversal” films were designed to create a “negative” image.  The negative image was developed in a chemical bath process in the darkroom.  Then, a second process was used to expose photographic paper (coated with a silver crystal emulsion of its own) to yield a “positive” image.

I believe there is a learning “take-away” from the color transparency film story

For many photographers – particularly nature and outdoor photographers – a process called color transparency film, became the medium of choice.  The color transparency was designed primarily to be projected onto a screen by shining a light through it.  It was also possible to create prints for personal use and for publishing with these images.  In its early stages, this process was confined to a very complex development process, that required very expensive equipment.  Perhaps the first and most famous was the vaunted “Kodachrome.”  Later, processes were created that would allow a less expensive, more routine form of development of the film.  The draw of the color transparency was its detail and realism.


Color transparency film is rarely used anymore, primarily because of the modern digital sensor.  Film had certain limitations, including relatively low ISO ratings (particularly in relationship to grain).  While the film industry made wonderful advances – particularly during the 1990’s, the arrival of digital sensors turned the photographic industry on its “ear.”  Suddenly, we could have a variable ISO “film” in our cameras.  And the quality of digital sensors has continued to get better and better, allowing for a relatively grain-free image at previously unheard of ISO ratings in the tens of thousands (compared to perhaps 200 ISO in a color transparency film).

If digital is so good, why do we care about all this?  Aside from the fact that history is interesting to some of us, I believe there is a learning “take-away” from the color transparency film story.

Our eyes are amazing biotechnical wonders.  Those familiar with cameras that allow user input, are perhaps familiar with the established system used to characterize the amount of light allowed to “expose” the medium (whether film or digital sensor), known as “f stops.”  Scientists say that the eye is altogether capable of seeing a range of up to 30 stops (though, at any given time, depending on lighting conditions, the useful range is perhaps closer to 10 stops).  Neither film nor digital sensors are capable of that much range (though digital technology will probably get there one day).  Because of this limited range, what we are able to record and present is much more limited that what our eye can actually see.  The magnitude of this range is known as “exposure latitude.”

Our eyes are amazing biotechnical wonders

Without getting into a detailed analysis of the various and relative exposure latitudes of different films and digital sensors, knowing these limitations is instructive.  As a general rule, B&W film had greater latitude than color negative film (perhaps comparable to the best digital sensors).  But color transparency film had nearly zero practical latitude.  When shooting slides, I would often under or over expose by 1/3 stop.  Any more than that and the image exposure just began to deteriorate.  So how is that useful?  It forces us to be thoughtful and careful about our exposure techniques.  I learned early on that I could be a bit sloppy when using negative film and still get acceptable exposure.  With slide film there is no margin for error.

But if other media is more “forgiving,” why does this all matter?  Well, what you can see in the darkroom is that there is a lot more you can coax out of a well exposed negative than a poorly exposed one.  And sometimes that is the difference between “acceptable” and “desired” results.  Using color transparency film was an in-your-face demonstration of how critical correct exposure is.  I have always thought of my digital sensor recordings as “digital negatives.”  And, much like the physical film “negatives” the quality of the “digital negative” critically impacts what you are able to do with it in post processing.  Getting correct exposure will yield desired results!

This image, made on Fuji Velvia; the most colorful and saturated film of the day, even with digital “enhancement” shows the more subdued colors and contrast ranges of transparencies

Of course, the comparison between film and digital is not exact.  There is a “science” to correct exposure with a digital image, and the response to exposure latitude is mathematically different.  Enough so that different and new techniques evolved for exposure judgement.  This technique, know as ETTR (or “Expose To The Right”), recognizes use of the graphic, “Histogram” for judging exposure.  I explain this exposure theory and technique in The Perfect Histogram, posted here in 2010.  While again, not an “apples-to-apples” comparison, there are many parallels to shooting with transparency film and optimal use of the digital sensor.

So, to my original question, do we take digital sensors for granted?  I believe many of us do, by not doing the “homework” involved to understand how these marvelous tools do their work.  The “cover” image was taken with my Smart Phone (the ill-conceived Blackberry Priv – Blackberry’s last ditch stand and attempt to compete in the Android world).  My first digital camera had a sub-2 megapixel sensor and produced, small, rather low-quality images.  Today’s smart phone cameras rival nearly any other small-sensor camera out there.  Most of them do not have the ability for significant user technical input, but the ability of the software to “do it for us” yields some impressive and often acceptable results.  But I will stick to my more sophisticated equipment and my knowledge of it, to obtain desired results.  And if you want a “tough lesson” learning experience, grab an old manual SLR camera and a roll of Kodachrome 25 and make some images!

I am experimenting with a beta version of WordPress’ new “Gutenberg” editor, which uses “blocks” of information.  Like anything new, there is a learning curve.  And bugs.  I like the ability to customize backgrounds, and to insert multiple images as “galleries” instead of just a single image at a time.  I am not sure I like the captioning,  I like that they have added drop caps (my prior solution was to make just the first letter in a bolder, larger font).  I do not like the in-your-face, hugeness of the drop caps.  I hope the final version gives us some more adjustability.  Likewise, I would like the ability to use font colors in the blockquotes, and vary the fonts within the text boxes.  Time will tell, but I apologize for any “wonkyness” here.

Advertisements

Book Review; Black & White Digital Processing

Creative Black & White; Digital Photography Tips & Techniques – Harold Davis  –  Recommended

Black & White Photography; The Timeless Art of Monochrome – Michael Freeman  –  Suggested

It has been a while since I reviewed a book here.  Indeed, these days, to think the ever younger population would even be interested in a hard-copy book might be simply quixotic.

Followers here know that I have recently ventured back into the genre of B&W imagery.  Rather than review one book here, I am going to tackle two books:  “Black & White Photography; The Timeless Art of Monochrome,” by Michael Freeman; and “Creative Black & White; Digital Photography Tips & Techniques,” by Harold Davis.  I have a rationale for reviewing these together.  For one thing, I think reviewing them separately will cover already “ploughed” ground, and would make for a couple of repetitive blog posts.

There is no such thing as a “complete” textbook – on any subject

But perhaps more importantly, if fits with a philosophy of learning that I will espouse.  I should first acknowledge (as I may have alluded to at the beginning of this post) that we all learn differently.  I have many friends who shoot, and who have never (or at least rarely) picked up a book on any photographic topic.  I suppose I am not preaching to them, but in some cases, I still believe they might be pleasantly surprised at what the “deeper dive” might reveal in terms of pleasure and interest in topics photographic.  But for those of us who are students and learn by books and written materials – either because they learn best that way, or because they have too, I hope my thinking resonates.

I am not a fan of the “star” rating system Amazon uses

There is no such thing as a complete textbook in any subject.  Indeed, when I see “The Complete….” anything, in a book, its credibility immediately erodes a bit (though it is just a title, and I do try to keep an open mind about what might be between the covers).  As a teacher and writer (both on a relatively small scale, but nonetheless contributing to some hands-on experience and knowledge), I know that it is not possible to find a “textbook” that is complete in its coverage.  Every subject needs to be supplemented and augmented by other materials; often written.  As a college student, my more rigorous instructors routinely assigned a “reading list” of books which were not the institution-chosen and assigned textbooks.  This is because they knew none of them alone were going to really impart the rounded subject knowledge necessary to become proficient.

I reviewed these books on Amazon and made the same observation.  I gave them both 5 stars because I thought they both deserved it.  As an aside, I am not a fan of the “star” rating system Amazon uses.  As a writer of two eBooks, myself, I have seen how that rating system can severely skew the perception of the book and I suspect skew sales in the same way.  That is why my rating system is different, and I think more useful to the purchase decision.  In so doing, I am not suggesting that either book is complete, perfect, or even without some shortcomings.  They both have them.  But what I want to know as a reader is are they worth the purchase?  Will they be a worthy addition to my resource library, and is there enough worthy material to justify the purchase of the book.  In both cases, I believe the answer is yes.

  My rating system is different, and I think more useful to the purchase decision

Freeman and Davis are both accomplished professional photographers and writers.  The former does not automatically beget the latter J.  There is some pretty pedestrian stuff out there.  Too many books today are just a re-hash of basic photography and Photoshop principles, in the guise of something specialized.  They may have their place, but I tire of picking up a book that purports to “take my – you fill in the blank – to the next level,” and then spends 75% of the book telling me how “f-stops” work, what the depth of field and focal length relationship is and how focal length relates to sensor size.  I also tire of the books spend an inordinate portion of their pages on basic techniques in Photoshop and other software.

Don’t get me wrong.  We need books on those topics.  I keep Martin Evening’s “text” on Photoshop CC right next to my computer and consult it often (“Adobe Photoshop CC for Photographers;”).  But it does not purport to be a specialized book.

So it is a pleasant plus to note that both of these authors tell you these are not “Photoshop How-To” books.  And other than showing us steps as they specifically relate to the topic, they require at least an intermediate knowledge of the underlying software (mostly Photoshop and Lightroom).  I found myself lacking some of that knowledge at times and having to consult my Photoshop generalist book(s).  That’s ok.  My knowledge base is from numerous accumulated sources.

I bought and will keep both of these books in my library

What I am looking for in books like these are whether they impart what they purport to – in this case, teach me something about Black and White imagery, in the context of digital photography.  And, when they do, do they impart enough (quantity and quality) to justify their purchase.  I think both of these books clearly do.

Black and White Photography; Michael Freeman – Suggested

Interestingly, both of these authors chose to divide their books into 3 major sections, dealing with some of the background of B&W photography; Digital theory and Techniques; and then a “Creative” section.  In Freeman’s case, they are chapters 1 -3.

The first “Chapter,” entitled “The Black and White Tradition,” covers some history of black and white photography.  But it does so in a manner that is brief enough not to lose the reader, who – after all – probably bought the book to learn about digital black and white techniques.  But there is enough information there to bring context.  I think Freeman does this really well.  He also talks about the “theory” of black and white, and how concepts like tonality, shape, texture, and lighting greatly affect the black and white image.

Chapter 2, entitled “Digital Monochrome,” delves more deeply into the digital side of things.  As a base for understanding, Freeman explains how the digital capture sensor is built and notes the difference between the “linear” response curve of digital capture and the traditional response “curve” of film.  While this may seem overly technical for the stated purpose of the book, I think it is important to understand why we make the digital “moves” we do when operating the software.  This is well done and illustrated, with again, just enough information without overwhelming the reader.

Freeman spends a little time mentioning some of the software applications available other than Photoshop, including the NIK Silver Efex and the ON1 programs, among others.  This is a nice, if small, departure from what is the “norm” in books with an overwhelming emphasis on Photoshop.  I have Photoshop and am not sure I could “live” without it.  But I sure know a lot of photographers who do not have it and get along perfectly well.  So it is nice for a change to at least have some “honorable mention” of alternatives out there.  I think that Adobe Lightroom and the up and coming ON1 RAW suite are going to give most photographers every tool they really need.  And today, if I were going to have to pick, I would lean toward ON1.

The next few sections dealing with black and white processing are really the meat of the text.  They describe several methods for conversion of digital images to B&W, and a number of useful adjustment techniques using the powerful tools available in software.

It is here where the book should shine.  And content-wise, is does not disappoint.  However, the presentation, unfortunately, leaves a little tarnish on the shine.  There are numerous instances where the author makes reference to an illustration, or a Photoshop tool that he relies on, as if it were presented as an illustration in the book.  But the illustration is nowhere to be found.  At times it seems like it should be an illustration and it is just plain missing, leaving the reader at first searching for it and then scratching her head, wondering what the ….? For example, he will often say something like, “as the histogram in this image illustrates …..” and then rather than having a histogram as an illustration for the image, the book will show the image and occasionally some sliders for the suggested adjustment.

A number of times, he walks us through the process he uses to enhance an original image, and notes that the final image is “better” because …. And then the original image is not shown to us in the book.  It just seems logical that you would do that in order for the reader to see the beginning and the result of the steps he has taken us through.  Sometimes the “stages” are illustrated but not the original image.  This is not consistent throughout the book.  Perhaps some more rigorous editing would be in order here.

But look, both of these books warn the reader that they are not Photoshop tutorial books, and that the reader should have at least an intermediate grasp of Photoshop and digital post-processing.  So it is easy enough to “infer” in the above instances, and I certainly would not let it deter me from purchasing, reading and using the book as a reference.  On balance I felt there was a lot of knowledge imparted, and a fair amount of inspiration to forge out on my own.

Creative Black & White; Harold Davis –Recommended

I think this is a book that is well worth the price for any photographer who (like I do) likes to learn by reading and likes to “get under the hood” a little bit, and wants to work with Black and White digital processing of their images.  Interestingly, this is a 2010 book (while Freeman’s is a 2017 publication).  One would think it is becoming dated, but it is not, it is still very much applicable and useful.

Much like the Freeman book, this book is divided into 3 major sections.  Freeman goes into some detail about B&W photography history comparing film to digital capture.  Davis, instead, uses his first section more as a “philosophy of B&W shooting” piece.

I thought the first section in Davis’ book could be thinned by about 2/3.  It just seems to repeat itself, and repeat itself.  He also has a tendency toward “flowery” language.  At times, I found myself noticing that, instead of the information it was trying to impart.  To me, that detracts from the mission.  But we all speak and write our own way – and to each his own.  None of the criticism here should, in my opinion, deter a purchaser.  This is a very good addition to my own library, and I learned (and will no doubt continue to learn) a lot from it.

Once I got into the second section – which is really the “meat” of the book in my opinion, I forgot about any negative tendencies and it very much held my attention.  Davis does a great job – almost in a “cookbook” formula, of illustrating a number of ways to handle B&W conversion, along with the whys and hows.  He gives – in most instances – a step by step explanation of how he does the processing (mostly in Photoshop) with enough information to see and accomplish the result, without getting into an “in-the-weeds” tutorial on Photoshop.  I like that.  The second 2/3 of this book did everything it promised and was everything I expected.  I will have this book on my bookshelf next to my workstation and will no doubt consult it often.  I am looking forward to experimenting with the techniques I learned in the book and truly believe it is worth a photographer having in his or her library.

Summary

I bought and will keep both of these books in my library.  You may have noticed that I rated the Davis book higher.  It is a book that has a lot of “hands-on,” practical information and applicability to what the prospective reader is likely looking for:  how to process my images to B&W in the best technical way.  In that sense, I think a photographer who is looking at learning about B&W conversion of digital images (and maybe even an experienced person) will find this an immediately useful “cookbook” for this purpose.  That is why I recommend it.

The Freeman book, much like all of his books, is more theoretical, and in my view looks more to inspiration and aesthetics.  That is why I “suggest,” rather than recommend it.  It will not be everyone’s cup of tea.  In one sense, it may get a little too far “under the hood.”  That is something I like because I am wired that way.  But many people would rather let someone else do the mechanics and concentrate on the driving.  I think Davis’ book fits the latter bill better.  I personally look for inspiration and some of that detail, and I enjoyed Freeman’s book every bit as much as the Davis book.  I will keep them both and both rated 5 stars on the Amazon review process.  To use a currently popular “texting” phrase, YMMV.

As always, thanks for reading and I would welcome comments.

Size Matters!

Certainly, a hackneyed, old phrase, but in matters of digital photography, it is a fact. The size I am referring to is the digital sensor, but not megapixels; physical size. There are a fair number of parallels to the film-based systems we used before the so-called, “digital revolution.” But with digital sensors, there is a significant difference; technology. Very much like the computer industry, by the time the latest and greatest sensor hits the market, it is already “old technology” (there were major technological advances in film, too, over time, but they happened in a matter of years, rather than months).  This is a very technical subject that many others out on the net explain in technical and engineering details that I cannot begin to match.  This is a layman’s perspective.

The consumer camera began to drive new technology advances

The first digital cameras were adaptations of 35mm Single Lens Reflex (SLR) camera bodies that were used to build digital imaging tools (today referred to as a Digital SLR; or DSLR). They had very small imaging sensors (significantly, smaller than the rectangular cross-section of a single 35mm film frame), and were capable of producing only around 1.2 megapixel (MP) images. They cost $20,000 to $25,000; not within the budget of most photo-enthusiasts.

Digital image-making brought a new phenomenon to the camera manufacturing industry. Suddenly, the consumer camera (we often refer to them as “point and shoot” or “P&S”), began to drive new technology advances which often first appeared in the consumer P&S cameras, only to be put into the higher-end “pro” cameras later.

Sensor Sizes Compared

How does this all relate to sensor size? The P&S cameras have a much smaller image sensor in them than the DSLR cameras and the newer Medium Format digital cameras that are now available on the market. I currently routinely carry and use 3 different cameras: a Canon G12 P&S, a Nikon D7000 “DX” sensor camera, and a Nikon D700 “FX” sensor camera.  As the illustration shows, there is a pretty remarkable difference in sensor sizes (if you would like to do your own comparison, I used this really cool tool to make this illustration). Especially when we can upload and view all three of these at relatively the same viewing size on our computer monitors, and—within reason—make similar-sized print images from all three. But there is a notable difference in the quality of these images.

Why did the original cameras not have a sensor identical to the 35mm film cross-section that those bodies were designed for? The answer is simple; technology and cost. The technology that continues to “knock our socks off” today was the most limiting factor back in the late 1980’s. The cost to manufacture even a 1.2 megapixel small physical sensor was prohibitive. A 35mm size sensor cost as much as 20 times the cost to manufacture the smaller sensors. And while over time manufacturers rapidly designed and manufactured sensors holding many more photo-sites (hence, more megapixel capture capability), the cost to manufacture larger physical sensors remained expensive. This explains why the cost of the so-called “full-frame” DSLR is still substantially higher that a higher megapixel DSLR with the smaller sensor.

Why weren’t the original sensors identical to the 35mm frame size?

Megapixel Wars.  For the first 10 to 12 years after the introduction of the consumer-affordable DSLRs, there was a huge emphasis—and indeed a “race”—for more and more megapixels. Megapixels translated in many people’s minds into higher quality. There is some truth to this, but it is only part of the story.   When I talk about “size” here, I really mean the physical size of the sensor, more than the number of megapixels.  As Thom Hogan recently noted in his D800 review, the megapixel increases are linear, not geometric.  In other words, the 36 megapixel sensor in the D800 does not create images 3 times larger than the D700’s 12 megapixel sensor (in fact, Hogan estimates that the increase from the D700 to the D800’s image sizes are about 70%).  The arguably more important part of the story is the quality of those megapixels.

My first DSLR was the Nikon D100; a 6 megapixel camera. My “upgrade” to the D200 was 10 megapixels. My current “pro” model D700 is a 12 megapixel camera; while my “backup” D7000 is a 16 megapixel camera. Logically, it would seem that the progression from D100 to D7000 kept getting me to the best sensor. But that is not the case.  The older, 12 Megapixel D700 sensor still yields a much higher “quality” image than the 16 Megapixel D7000 sensor.

You might think that the progression from D100 to D7000 kept getting me to the best sensor. But that is not the case

At the time I bought the D100, there were point and shoot cameras available with higher than 6 megapixel counts. But I could still produce a cleaner, better quality image with the D100 that could be printed larger (I have 13 x 19 prints of images made on the D100 that are indistinguishable at that size from prints made from D700 12 megapixel images). Nikon’s newest “entry-model” consumer DSLR is the D3200, which is a whopping 24 megapixels (only the pro D800 beats it with 36 megapixels – the largest megapixel DLSR available at this writing). One would think it should make “better” images than the only 12 megapixel D700. But it cannot even come close!

The primary reason for this is size. You can readily see the difference in the image sensor sizes of my 3 current cameras. And the number of photo-sites that are packed onto the sensor and the size of the photo-sites make a huge difference in the quality of the image produced. This is most obvious in the low frequency (shadows and low light) side of the digital photographic equation.

Cruise Dock; Port Everglades, FL
Copyright 2012 Andy Richards

Noise.    When a sensor captures light it is converting light to electrical signals and certain “stray” signals can produce a grain-like pattern or effect in an image that is referred to as noise. This noise is largely created by low frequency signals (often the product of low-light conditions), but also by heat and other anomalies in the electronic processor. A small sensor, with many photo-sites packed onto it can create more degrading noise than a larger sensor. It can generate and accumulate more heat because it has less area to dissipate the heat energy. At the same time, the larger photo-sites are capable of capturing more and better detail, yielding a better quality digital image. These higher quality “raw” images, in turn, yield much better files to work with in the post processing stages. The image here, taken at the Princess Cruise Terminal in Ft. Lauderdale, Florida, in the early morning hours, demonstrates this. The noise is simply un-manageable. The same shot, taken with the D700 would have been salvageable.

G12                                         D7000                                         D700

Angle of View.    Another controversial area over the years has been the concept often referred to as “crop factor,” or “magnification factor.” When manufacturers began making digital interchangeable-lens camera bodies, they simply adapted the current, 35mm SLR body. While one might wonder why they didn’t just design and build a new “digital” body, the most obvious answer is probably again based on economics. It was probably much less costly to adapt the 35mm SLR body. And, it meant not having to create a completely new lens mount and require all of us to buy a whole new series of lenses. They had a ready-made consumer, just waiting to purchase the DSLR and use their existing lenses.  The composite above is shots from the same tripod position, taken a 140 mm on all three cameras, at their maximum aperture.  The G12 is obviously with its built-in lens.  The Nikon is with a 70-200mm f2.8 zoom.

The “crop factor” / “magnification” debate doesn’t really matter

The first sensors were significantly smaller in cross section than the 35mm film frame. The SLR lenses were designed for the larger 35mm cross-section. So, the sensors only used some of the inner part of the lens circle, effectively “cropping” the outer part. The effect of this was to create a narrower angle of view. The appearance is a “telephoto effect.” The practical effect was that you lost your wider angle and “gained” a longer view on all of your lenses, by a factor of 1.3 or 1.5. Because these sensors were similar to the size of the (largely failed) Nikon Pronea APS film camera, they came to be known as “APS” size sensors (Nikon has since denominated their “APS” sized sensor as a “DX” sensor).

There is no such thing as a “full frame” camera

There has been a considerable amount of debate and even “flame wars” on the internet over this concept. It really doesn’t matter. The debate is, for practical shooting, silly. The reality is that if you have a wide angle lens, on an APS sensor, it just won’t view or capture as wide. Conversely, if you have a longer lens, you get a longer angle of view on the entire sensor, effectively increasing the “telephoto” effect of the lens. Depending on your intended use, this can be a good thing or a bad thing (I actually made my recent backup decision to buy an APS size sensor partly on the premise that it would give me slightly more length for certain wildlife shooting).

Likewise, the controversy over whether a camera is or is not “full frame” is non-productive. But I’ll weigh in anyway :-). There is simply no such thing as a “full-frame” camera. I know that might draw some debate, but it is just a reference point. To a lifelong 35mm shooter, “full frame” means 35 mm (24mm x 36mm). But to a Medium Format or View Camera user, that’ hardly “full.” Indeed a View Camera 8 x 12 sheet of film makes a so-called “full frame” 35mm look like what it really is: a Postage Stamp! Again, it’s a reference point. To my way of thinking, the larger the better.

But there are practical considerations. When I bought my 6 megapixel APS frame D100, I carried a couple 2G flash cards around. With my 12 megapixel “full frame” (Nikon refers to their 35mm size frame as “FX”) D700, I use 8G cards. With the new D800 36 megapixel FX sensor, I don’t even know how large the cards would have to be. And with each of these increases in file size, an equal increase in hard drive storage and computer processing power (memory) is needed. At some point, it may become overkill. When Nikon announced their Flagship D4, at “only” 16 megapixels (same as the D7000 consumer body), many of us thought it might signal the end of the megapixel wars). But they have since released the D800 FX 36 megapixel body. Interestingly, the D800 is the “entry-level pro” camera and the D4 is the flagship pro body at a significantly higher price point (suggesting that a lot of working pro’s don’t consider the megapixel issue significant anymore at 16 megapixels). I cannot personally see a need for more than double the capacity of my D700 which creates some splendid digital images, in low light conditions.

It is difficult or impossible to get those pleasing out of focus effects on a point and shoot camera

Canon G12; 140mm; f4.5

Depth of Field.    Interestingly, sensor size also affects depth of field. This is analogous to the film reference above (as was the comment about “full frame, Medium and Large Format). It relates to the field of view and image size geometry. I am not capable of explaining the science, here and will leave it to more capable persons. But as a general rule, the smaller the sensor, the greater the depth of field for a given lens focal length. This explains why it is difficult or impossible to get those pleasing out of focus effects on a point and shoot camera.  As you an see, the G12 image, which is shot at its longest focal length and its widest aperture, still captures the background in reasonably sharp focus.  On the D700, everything is blurred except the main subject (of course a big part of that is the wider aperture).

Nikon D700; 140mm; f2.8

In the end, it is still first and foremost, about quality! When the consumer affordable DSLRs first came on the market, there was an immediate hue and cry for a “full frame” (i.e., 35mm size) sensor. The main reason, I believe, was because those of us used to using 35mm didn’t like the change required when thinking about and using our existing lens arsenals. I bought an 18mm lens and it solved my concern. Over time, the camera lens manufacturers have answered the call by designing lenses specifically for the APS sensor size. This has created some of its own issues, as we now have 35mm size sensors available. A “DX” lens on my “FX” D700 will have a big black vignette circle in the viewfinder, but will simply crop the image to the DX format. It just means we have to plan and think about what and how we are shooting.

My primary criteria for purchasing a camera will always be its sensor quality

When the D700 came out, I immediately decided to buy it. The sensor size really had absolutely nothing to do with it. I had “moved on” to the smaller sensor / lens combinations and had a bag of lenses that worked well for me. Buying the D700 made me have to re-think that and it was, frankly, in the short run, a nuisance to do so. Eventually I have sorted that all out. But my primary criteria for purchasing the D700 – and it will probably always be my primary consideration in purchasing any camera, was sensor image quality. And there is just no question on my mind that the camera I have in the bag that yields the highest quality image, is the one with the biggest sensor.

For lots more than you ever wanted to know about sensors, sensor size, and electronics, see Wikipedia and this DPreview page.