Misinformation

[bazooka]

/soapbox

When I read misinformation here or on any forum, I usually just think it's entertaining. There is always someone here to correct that misinformation. But then I read this.... A deeper look into Depth of Field ... a 'published' article and I just want to strangle the living daylights out of the author and the commenters saying it's the best explanation they've ever read! With 20 some posters responding, only 2 actually called him out on factual errors.

"Depth of field is ultimately effected by two things: The aperture of the lens as we have just covered and the distance between subject and background."

*facepalm*

/end soapbox

 

[Kerbouchard]

Most people are stupid. It sucks, but it's just kinda the way it is.

 

[oldmacman]

Didn't read the article, but DOF is affected by aperture and distance (among other factors). What is your specific issue with the post?

 

[unpopular]

yeah. I am not really seeing it either. Aside from "foreground" and "background" being artificial and vague mesurments, I am not sure what the issue is. He likely meant "DOF is affected by aperture area and distance from the focus point".

I agree that thinking of everything in front of the focus point being the foreground, and to the rear teh background is kind of hokey - but I think this is more an issue of semantics than anything technical.

Then again, I misunderstand the technical angle DOF often.

 

[Overread15 3]

Depth of field is also affected by the circle of confusion which is linked to the size of your recording medium (ie your film/sensor size). The author also mentions that f32 is a common macro aperture for depth of field without even touching on the fact that most macro shooters won't ever go that small because of diffraction softening.

In the end its not that well written and skims over a lot of the detail that the author attempts to say that are including (as well as the "too much bokeh" title which is just confusing to anyone). I kinda get the feeling it was written just for the better beamer purcahse link plug

Sadly there are a lot of these kind of blog out there and its one reason that googling for info isn't the most reliable source since it can only show popular and well designed stuff for the search engine and does not validate the information.

 

[Derrel]

The internet is FULL of people who do not understand technical terms or concepts of photography. Why, just last week, we had a huuuuuuuuge discussion about the meaning of the word "Exposure". In that discussion we also had one of this site's most technically-minded shooters introduce the concept of Exposure Value, an entirely different concept than Exposure...and muddy the waters... by bringing in another, entirely different concept

The internet is a great place for the blind to lead the blind. People with two or three years of web-based learning, but no study of acknowledged texts, are free to post blog entries and articles and participate in forums. Widespread, nearly instantaneous dissemination of half-baked ideas is one of the dangers of the web. Misinformation can be repeated so often and so widely that it soon becomes "fact". Take the meaning of the term "bokeh"...it is so,so,so commonly misunderstood that iof one attempts to supply the correct definition of it, one will often be immediately corrected by some newbie who think it means shooting with a heart-shaped matte in front of the lens so as to produce cute little out of focus "heartsies" on the Christmas tree lights!

Depth of field, out of focus backgrounds, background blur, selective focus, and bokeh---all of those subjects are best learned about from acknowledged masters. Not random interweb bloggers...

 

[CCericola]

Everything on the interweb is true. If you find two things that contradict each other, they are both true.

 

[Tee]

Everything on the interweb is true......

....except when a newbie "pro" gets their work critiqued and they can't handle the truth.

 

[dots]

Didn't read the article, but DOF is affected by aperture and distance (among other factors). What is your specific issue with the post?

I'd like to know too.

 

[analog.universe]

To say that it's ultimately affected by two things is misleading. Focal length is left out of the discussion. It's briefly mentioned toward the end of the article, as if the correlation between focal length and depth of field is assumed to be known. If you're going to write an article about depth of field fundamentals, focal length needs to be as important as subject distance and aperture.

 

[dots]

Thanks for adding that.

 

[Helen B]

...
Why, just last week, we had a huuuuuuuuge discussion about the meaning of the word "Exposure". In that discussion we also had one of this site's most technically-minded shooters introduce the concept of Exposure Value, an entirely different concept than Exposure...and muddy the waters... by bringing in another, entirely different concept
...

Derrel, shame on you for being such a weasel (my apologies to weasels). Why not discuss this in a rational manner in the original thread, instead of making blanket, unsupported statements in a different thread?

Your statement that "the concept of Exposure Value [is] an entirely different concept than Exposure" is an excellent example of internet misinformation, however. Ev is simply a formal enumeration of of one of the meanings of the word 'exposure' and one that happens to be defined in an American standard. It was mentioned in context - the relevant part of the discussion was about whether there was only one correct definition of 'exposure' (intensity x time) or more than one. Ev is an example of a technical definition that refers to one of the common, meaningful usages of the word 'exposure' by photographers that is not intensity x time.

Best,
Helen

 

[unpopular]

Being that Derrel also suggested that exposure meters that record in "RGB" can somehow bypass the most elemental physics and magically gain insight that previously could only be determined by incidence metering, I am unsure that he is qualified to criticize this or any other advise given...

I will admit that I did muddy the waters in this particular thread as well, but only because I cannot imagine how one would accurately meter off the subject using array metering, such as Nikon matrix mode. This isn't to say the mode doesn't have it's place, but by that point I myself was so befuddled, I figured I'd just let it go.