Archived posting to the Leica Users Group, 2015/01/16
[Author Prev] [Author Next] [Thread Prev] [Thread Next] [Author Index] [Topic Index] [Home] [Search]Well the idea that we're getting into an era now where sensor speed is not like film speed at all and is handled much differently. If that's what's happening its not a question of my or anyone's opinion we just do it. I can guess and guess wrong if that's really going to happen or not. Feels wrong to me. I don't like it. But I'm wrong myself at least once a week. In the film era I was not much on pushing film and very much not into pulling. I felt a film had a certain speed and if you used a different speed with your developer dilution combination then you were shooting on the wrong part of the curve. That may not relate directly to this new way of dealing with sensor exposure. The only person I've run into who does this is that guy on the lug last month. On 1/16/15 4:51 AM, "Philippe Amard" <philippe.amard at sfr.fr> wrote: > My contribution was just about how deceitful usual (mis)conceptions of > ISO are Mark. > > Hope they could help you a bit as they did me. > > Amities > Auto everything Philippe > > > Le 15 janv. 15 ? 17:20, Mark Rabiner a ?crit : > >> Thanks Philippe I look this up and the all see this is relevant more >> for >> Canons than Nikons at this point. And not just Sony's or Fuji's. >> I'm not >> looking forward to shooting with near dark LCD screens to not be >> able to >> see. I think when this approach is viable we'll able to see what >> we're >> doing in the back of the camera like we always have been able to see. >> I still have my Nikon D700 set at Auto ISO and will hopefully not >> find out >> that I've been doing it wrong for 5 years and more. I'd be amazed to >> see >> that. We had a guy on the LUG doing that last month I had mixed >> feelings >> about his whole mind set. >> I guess more of a chance of this relating to my next camera. >> Which would be a Nikon D760. As they are pulling the 750's off the >> shelves. >> >> The Nikon 750 sensor debacle kind of lines up with the Leica CCD >> sensor >> corrosion scandal. Just in time for 2015. >> We are still working out basic bugs in this whole digital thing. >> >> >> On 1/15/15 5:14 AM, "Philippe Amard" <philippe.amard at sfr.fr> wrote: >> >>> >>> Le 15 janv. 15 ? 10:09, Mark Rabiner a ?crit : >>> >>>> I'm not sure if we have a real >>>> sense of what iso we can use it at now?!? >>> >>> >>> This might help add to our confusion circle ;-) >>> >>> >>> DR Modes and the ISOless APS-C Sensor >>> >>> You may have heard that Fuji?s APS-C cameras are all based on modern >>> ?ISOless? Sony sensors. These sensors are used by several leading >>> camera manufacturers, such as Sony (of course!), Nikon, Ricoh/Pentax, >>> Leica and Fujifilm. >>> >>> The ?killer feature? of ISOless sensors is their ability to rely on >>> digital gain (as opposed to analog amplification) for the most part >>> of >>> their operation. Digital gain can be applied anytime during your >>> workflow?before and after the RAW file has been created. As a matter >>> of fact, it?s better to apply digital gain after the fact?when the >>> RAW >>> in processed in a converter. This is also the reason why Fujifilm >>> RAWs >>> don?t go beyond ISO 1600. They remain the same?any further gain >>> between ISO 1600 and ISO 6400 is applied digitally during RAW >>> conversion. >>> >>> This means that in high-ISO scenarios, achieving ?perfect exposure? >>> before you press the shutter button doesn?t really matter. You can >>> just as well change the exposure later in the RAW processing phase? >>> either in-camera, or with Lightroom (or with another RAW converter) >>> in >>> the comfort of your home. Click here to read a forum thread with a >>> demonstration of this feature. >>> >>> Between base ISO 200 and ISO 1600, ?mixed? analog/digital >>> amplification maintains a slight quality advantage over ?pure? >>> digital >>> gain. That?s why your camera is still using at least some analog >>> signal amplification up to ISO 1600. Enabling the DR function >>> basically switches the mixed analog/digital process over to a pure >>> digital gain (or tone-mapping) process for either one (DR200%) or two >>> (DR400%) analog signal amplification stops. >>> >>> Let me give you an example: Shooting an image at ISO 800, DR100% will >>> result in an ISO 800 RAW file that?s based on an ISO 200 exposure >>> with >>> two stops of mixed analog/digital amplification/gain. Shooting the >>> same image at ISO 800, DR400% will result in an ISO 200 RAW file with >>> digital tone-mapping being applied during RAW conversion. This tone- >>> mapping is pushing the result to ISO 800 in the shadows and midtones, >>> while retaining bright highlights at ISO 200. You would have a hard >>> time telling the ?analog? from the ?digital? ISO 800 result when >>> looking at the shadows and midtones. You will however recognize that >>> the digitally processed DR400% version offers two additional stops of >>> highlight dynamic range. This is exactly what we want when shooting >>> scenes with high DR, like christmas markets with festive lights and >>> very strong contrasts. >>> >>> In other words: Yes, sensors have a fixed dynamic range, but the >>> actual dynamic range that can fit into your actual image file is not >>> just determined by the sensor, but by the signal processing and by >>> whatever happens during RAW processing. By applying ?adaptive ISO? >>> during RAW processing, you can expand the actual dynamic range of any >>> image by 1, 2, 3 or even more stops. The sky?s the limit, but for >>> practical reasons, there will always be quality considerations, since >>> the application of digital gain results in a similar image >>> degradation >>> as raising ISO values the old-fashioned way. >>> >>> >>> >>> >>> >>> Much more at : http://www.fujirumors.com/exposing-right/ >>> >>> Amities >>> >>> Ph >>> >>> >>> >>> >>> >>> >>> >>> One sees clearly only with the heart. What is essential is invisible >>> to the eye. Antoine de Saint Exup?ry in Le Petit Prince. >>> NO ARCHIVE >>> >>> >>> >>> >>> >>> _______________________________________________ >>> Leica Users Group. >>> See http://leica-users.org/mailman/listinfo/lug for more information >> >> >> >> >> -- >> Mark William Rabiner >> Photographer >> http://gallery.leica-users.org/v/lugalrabs/ >> >> >> >> _______________________________________________ >> Leica Users Group. >> See http://leica-users.org/mailman/listinfo/lug for more information > > One sees clearly only with the heart. What is essential is invisible > to the eye. Antoine de Saint Exup?ry in Le Petit Prince. > NO ARCHIVE > > > > > > _______________________________________________ > Leica Users Group. > See http://leica-users.org/mailman/listinfo/lug for more information -- Mark William Rabiner Photographer http://gallery.leica-users.org/v/lugalrabs/