Pages: [1]   Go Down

Author Topic: Top Ten Myths of Digital Photography  (Read 6072 times)

bjanes

  • Sr. Member
  • ****
  • Offline Offline
  • Posts: 3387
Top Ten Myths of Digital Photography
« on: January 05, 2012, 08:31:13 pm »

I just finished viewing the MythBusters session on C2PS where Michael and Jeff went over what they considered to be the top ten myths in digital photography and invited forum members to nominate other candidates for this list. From some of the recent postings I would suggest that a bit depth of 16 improves image quality with current digital sensors.

Regards,

Bill
Logged

Guillermo Luijk

  • Sr. Member
  • ****
  • Offline Offline
  • Posts: 2005
    • http://www.guillermoluijk.com
Re: Top Ten Myths of Digital Photography
« Reply #1 on: January 05, 2012, 08:32:38 pm »

Second myth: ETTR improves IQ thanks to having more encoded levels ;D
(as a few seem to know, in practice ETTR only improves IQ thanks to improving SNR).

« Last Edit: January 06, 2012, 06:45:12 am by Guillermo Luijk »
Logged

fdisilvestro

  • Sr. Member
  • ****
  • Offline Offline
  • Posts: 1854
    • Frank Disilvestro
Re: Top Ten Myths of Digital Photography
« Reply #2 on: January 05, 2012, 10:15:01 pm »

Second myth: ETTR improves visible tonal gradations ;D
(as a few seem to know, in practice ETTR only improves SNR).

Well, I think it actually does improve "visible" tonal gradations as a result of improving SNR, not because of having more encoded levels, (I´m also on the side that ETTR only improves SNR)

Quoting Emil Martinec in this thread (you`re mentioned there):

Quote
I think some of the quibble here is over semantics, or rather precision of language.  There is a distinction between 'encoded levels' and 'information'.  Having more levels does not necessarily mean more information.  What photographers who employ ETTR understand intuitively is that by increasing exposure they get smoother tonal gradations, and that is indeed because there is more information in the image due to higher S/N.  There are indeed more distinguishable levels because that number is governed by the S/N; and this number of distinguishable levels, it should be noted, is distinct from the number of encoded levels which is the number of raw values encompassing any given exposure zone in the image.  One can play all sorts of tricks with the latter without changing the S/N and thus the image quality, as Guillermo's example shows.

Guillermo Luijk

  • Sr. Member
  • ****
  • Offline Offline
  • Posts: 2005
    • http://www.guillermoluijk.com
Re: Top Ten Myths of Digital Photography
« Reply #3 on: January 06, 2012, 06:44:06 am »

That is correct, I reformulate the myth.

madmanchan

  • Sr. Member
  • ****
  • Offline Offline
  • Posts: 2115
    • Web
Re: Top Ten Myths of Digital Photography
« Reply #4 on: January 06, 2012, 03:46:55 pm »

I just finished viewing the MythBusters session on C2PS where Michael and Jeff went over what they considered to be the top ten myths in digital photography and invited forum members to nominate other candidates for this list. From some of the recent postings I would suggest that a bit depth of 16 improves image quality with current digital sensors.

Bill, as currently worded that's a bit vague.  "bit depth of 16" at which part of the imaging pipeline?  If you mean 16 bit output from the A/D converter on the chip (which is probably what you meant), then that's reasonable.  If you mean 16 bits used for tone rendering, then I would disagree.
Logged
Eric Chan

NikoJorj

  • Sr. Member
  • ****
  • Offline Offline
  • Posts: 1082
    • http://nikojorj.free.fr/
Re: Top Ten Myths of Digital Photography
« Reply #5 on: January 06, 2012, 04:16:34 pm »

If you mean 16 bit output from the A/D converter on the chip (which is probably what you meant), then that's reasonable.  If you mean 16 bits used for tone rendering, then I would disagree.
And then, comes 16-bit printing...
Logged
Nicolas from Grenoble
A small gallery

bjanes

  • Sr. Member
  • ****
  • Offline Offline
  • Posts: 3387
Re: Top Ten Myths of Digital Photography
« Reply #6 on: January 06, 2012, 04:57:35 pm »

Bill, as currently worded that's a bit vague.  "bit depth of 16" at which part of the imaging pipeline?  If you mean 16 bit output from the A/D converter on the chip (which is probably what you meant), then that's reasonable.  If you mean 16 bits used for tone rendering, then I would disagree.


Eric & Nicholas,

Yes I meant linear 16 bit output from the ADC of current cameras whose noise level does not really warrant that many bits. The extra bits do a good job quantifying noise and do no harm, but do waste storage space on the memory card. With such a camera, 8 bit rendering in Photoshop would be lossy and 16 bits (15+1 as we all know with Photoshop) would be appropriate. This point relates to a rather contentious thread elsewhere on LuLa.

Regards,

Bill
Logged

theguywitha645d

  • Sr. Member
  • ****
  • Offline Offline
  • Posts: 970
Re: Top Ten Myths of Digital Photography
« Reply #7 on: January 06, 2012, 07:27:12 pm »

The more the pixel resolution, the shallow there depth to field.

Print size is determined by the pixel resolution.
Logged

ErikKaffehr

  • Sr. Member
  • ****
  • Offline Offline
  • Posts: 11311
    • Echophoto
Re: Top Ten Myths of Digital Photography
« Reply #8 on: January 16, 2012, 01:31:21 am »

Hi,

There are two sides to the coin. If you find that you can make a A1 size print from say 24 MP you can probably make an A0 size from a 48 MP camera that will match in quality when viewed at the same distance.

The statement on Depth Of Field is also correct if you need absolute sharpness.

In general, the larger you print and the closer you view the more critical will sharpness related issues become. Looking at the image on screen at actual pixels is an extreme form of pixel peeping.

Best regards
Erik


The more the pixel resolution, the shallow there depth to field.

Print size is determined by the pixel resolution.
Logged
Erik Kaffehr
 

BJL

  • Sr. Member
  • ****
  • Offline Offline
  • Posts: 6600
Re: Top Ten Myths of Digital Photography
« Reply #9 on: January 17, 2012, 10:02:00 pm »

A bigger sensor alone gives better low light/high shutter speed performance.

The truth is that the advantage only comes when the larger sensor is used with about the same ISO speed, which in turn means using lenses offering about the same f-stop choices, which with the longer focal length needed to get the same FOV means larger effective aperture diameters, and so generally bigger lenses. When instead a smaller format can be used with a lens of equally large aperture diameter, and so with a lower minimum f-stop, then you get roughly equal lens size and the ”extra lens speed" of the smaller format and the "extra sensor speed" of the larger format roughly balance out:

”big glass" is the ultimate source of good low light performance (and low DOF), not just "big silicon".
« Last Edit: January 17, 2012, 10:03:51 pm by BJL »
Logged

Martin Kristiansen

  • Sr. Member
  • ****
  • Offline Offline
  • Posts: 1527
    • Martin Kristiansen
Re: Top Ten Myths of Digital Photography
« Reply #10 on: January 27, 2012, 12:25:52 am »

Hanging out on photographic forums getting into nit picking arguments will improve your photography faster than going out and actually taking photographs. The proof is some odd equation and a set of incomprehensible graphs. I can even post some jpgs as additional proof if you would like that might derail the discussion into a debate on image processing.

Image processing is best used on photographs of a colour checker. In fact that is what image processing is really for. Colour checker photographs

Which brings us to  my final myth. Colour checkers are what cameras are made to photograph. All other subject matter is a waste of time and proves nothing. 
Logged
Commercial photography is 10% inspiration and 90% moving furniture around.

NikoJorj

  • Sr. Member
  • ****
  • Offline Offline
  • Posts: 1082
    • http://nikojorj.free.fr/
Re: Top Ten Myths of Digital Photography
« Reply #11 on: January 27, 2012, 09:38:51 am »

Which brings us to  my final myth. Colour checkers are what cameras are made to photograph. All other subject matter is a waste of time and proves nothing. 
Hey, what about Siemens stars?  >:(
Logged
Nicolas from Grenoble
A small gallery

jalcocer

  • Guest
Re: Top Ten Myths of Digital Photography
« Reply #12 on: January 27, 2012, 09:51:45 am »

I've always been kind of in between with this one "more megapixels is better"
Logged
Pages: [1]   Go Up