Comments for Down to Brass Tacks

Comment on Pushing Exposures by Charles Lanteigne

Charles Lanteigne — Wed, 15 Dec 2010 15:29:19 +0000

There are indeed some differences in the pixel pipeline from camera brand and model to the next, even when the same sensor is used (which can be plainly observed when comparing files from the Nikon D3X and Sony A900, for example), but the facts remain the same: Changing the ISO changes the signal gain (something that happens prior to any processing), and is certainly not just a matter of post capture (be it in the camera or on the computer).

As for the “more information in the highlights” bit, that is a behavior of camera sensors, because their sensitivity is linear (double the photons = double the luminosity), which is not the way film (positive or negative) nor our eyes behave. When I say that slide (positive film) behaves closer to digital capture, I mean that when the highlights are blown, they cannot be recovered (the opposite of negative film, which must not be underexposed). “Exposing to the right” is only preferable when shooting raw digital, and is not helpful when shooting film or JPEGs, which should all be captured as close as possible to the desired exposure.

Unfortunately, when shooting in high contrast situations, whichever end of the tonality spectrum can be more easily recovered doesn’t help: either way the photographer has to make a decision as to what is more important, because both cannot be recorded simultaneously.

Comment on Pushing Exposures by Yannick Khong

Yannick Khong — Wed, 15 Dec 2010 07:33:23 +0000

Interesting enough, the behavior of RAW files on the “pushing” of exposures vary from one brand to the next. If the RAW data was dumped “as is” from the sensor we won’t be able to witness a significant difference between brands using the same sensor yet different “processors”.

Following your theory of more information in highlights (as it would be on negative film), it would be interesting to see the opposite happen. Like to compensate for overexposures in post. Especially when shooting RAW in high contrast situations.

Comment on Another Bunch of Web Concepts by Michael

Michael — Tue, 23 Feb 2010 14:36:37 +0000

Thanks for taking the time and sharing all this info with us. And seriously, you should be The Teacher, not just because you have the knowledge but also because it seems that you explain so easy everything, which is great!!!!

Comment on Camera Raw is not Just an Import Plug-in (Anymore) by Mark A. Cadiz

Mark A. Cadiz — Thu, 18 Feb 2010 02:38:40 +0000

Great review Charles on keeping maximum quality. Sometimes I tend to forget why I do certains things and your write-up has refreshed my memory and added more useful info to my brain!

Comment on Tethered Power Consumption by Charles Lanteigne

Charles Lanteigne — Fri, 12 Feb 2010 22:01:44 +0000

Well, Nikons behave that way all the time (they’re off, but something is still on, since the remaining frames stay visible — seems quite strange, from where I stand).

In this particular post, I was discussing specifically about what happens when shooting tethered — in that case, the Canon cameras never go to sleep (the top display is always awake). Unfortunately, I cannot comment on the behavior of Nikons, since I didn’t get a chance to see them at work in that configuration.

Comment on Tethered Power Consumption by J.

J. — Fri, 12 Feb 2010 17:23:25 +0000

Is that the same thing with nikon ? As the button of my camera is Off, I still see the number of picture left on my card. Is that what you call ”stand by” mode ?