Can someone cross post this video or at least let me know the thread that it was in so I can scan for it? :)
On Fri, Sep 12, 2014 at 1:16 PM, Igor PDML-StR <[email protected]> wrote: > > > I. > First, just a quick comment that while talking about outresolving lenses, > one should also keep in mind that due to the discretization of the pixelated > media, the effective resolution of a lens can be still reduced, even if the > sensor's pixels/mm number is larger than lines/mm number for the lens. (The > guy in that recent Nikon vs Canon video that was linked a few days ago in a > different thread discusses that.) So, increase in the pixel density of a > factor of 1.28 in principle can produce some significant effect for some > lenses if you are going from 6 MP to 7.7 MP. > > In this case, the same argument may apply for the sharpest lenses. > (Maybe even prime * lenses of Pentax?) > > > II. > With respect to the increase in the sensor's MPs in question, - > if we are talking about the technology advancement, - what is relevant is > increase in the density of the pixels. Indeed, the density increased by > a factor of 1.13 (=Sqrt(1.28)). > What is true, is that the higher the starting density is, the harder it is > to enhance it further. This applies to the recording media density (as in > HDDs), as well as the sensors. > So, from the SENSOR technology point of view, this is a valuable > advancement. > > > III. > As for practical advantage of having such a sensor in the camera, - > besides the possible one mentioned in I. above, - there might > be some others. Just one example is the possible improvement in > the optical stabilization (again due to discrete nature > of the pixels). > Also, ultimately, the availability of cameras with the high-resolution > sensors can boost the efforts of producing (and even mass-producing) > higher-resolution lenses, which make the more easily available and hence > (eventually) cheaper. > > But I think the practical advantage (in terms of quality of the photos) of > going from 5 to 7.8 MP is higher than that of going from 36 MP to 46 MP. > (see I. above). > > > [Nerd ON] > IV. > Sometimes percentage of the increase might not be a good measure, > while the absolute increase is. > I just wanted to give a few clear examples where the percentage is not a > good measure: > 1. A temperature increase of, say, 2 degrees F (1 degree C). > Does it matter if it from 2 F to 4 F or from 34 F to 36 F? > The corresponding percentages would be 100% and ~6%. > And, of course, in Celcius, the equivalent would be > ... well... 100% in the second place (from 1C to 2C), but I am not even sure > what to say about the first case, when it is from approximately -16.5C to > -15.5C. > So, it obviously depends on the scale! > > Well, I agree, this example is not directly applicable to sensors, whose > dimensions are using the absolute scale. And to make the comparison, I > should've used the absolute temperature scale (Kelvin). In Kelvin, > the changes would be from about 256.5 K to 257.5 K, and 274 K -> 275 K, > respectively. > > 2. Relevance of the change also depends on the effect that we are > considering. > For many physics processes that rely on the behavior of electrons, the > relevant measure would be the relative change (on the absolute scale, in > Kelvin). For many biological processes, the direct percentage change > probably would not be a good measure. The absolute change wouldn't matter > either... > E.g. a change of a human body temperature from 37C (98.6F) to 38C (100.4) is > unpleasant, but the same absolute change from 40C (104F) to 41C (105.8) > (which would be smaller in percentage) can be lethal ou. > So, this shows the relevance of the change to the process that gets affected > by this change. > > 3. Stan, with respect to your "home-economy" example. You are right, except > for those cases, where there is an "offset" of fixed costs. > E.g. if the bare minimum cost of housing is, say $800 a month. > Then for somebody earning $1000 a month, an extra $100 is more valuable > then $300 for somebody who is earning $3000/mo. The reason is > that the effective increase in the income that available for things other > then the housing would be 50% (from 1000-800=200), and a comparable relative > increase for the second person would be smaller (from > 3000-800=2200 to 2500 is less than 15%). > > Effect of the lenses becoming the bottle-neck of the performance is > similar to the "fixed-cost" offset described above. > > All these examples are just to support the point that one cannot just > blindly use relative increase (percentage or factor) in all cases. > > [Nerd OFF] > > > Thu Sep 11 09:45:58 EDT 2014 > Darren Addy wrote: > > I'm not denying that there is an appropriate place to use percentages. > It is especially useful in apples to apples comparisons. > I'm just saying that comparing APS-C to full frame AND to a completely > different era is apples to oranges, in my book. > > To go back to Mark's numbers, he's saying a 27% increase is > insignificant except from a marketing standpoint. The new K-S1 is a > 25% increase in megapixels over the past several years' 16MP models. > Even ignoring the other technology improvements along the way, I think > that 25% is a pretty significant increase. I can make is sound smaller > by terming it a 1.25 "factor" if I want to minimize it. > > Feel free to disagree, but that's my opinion. I think that we may just > be spoiled by seeing the flagship go up 50% from 16MP to 24MP. That's > partly due to the disruption caused by no (really) new DSLR models > during the Hoya to Ricoh transition. > > On Thu, Sep 11, 2014 at 8:36 AM, Stanley Halpin > <stan at stans-photography.info> wrote: >> >> >> On Sep 11, 2014, at 8:23 AM, Darren Addy <pixelsmithy at gmail.com> > > wrote: >> >> >>> That's a funny way of looking at it. First of all, almost all change >>> is incremental, but that doesn't mean it is insignifcant. If reducing >>> things to percentage increase was a valid way of comparing things, >>> then someone who went from bench pressing 460 lbs from 360 lbs >>> shouldn't be any prouder of the accomplishment than someone who went >>> from 60 lbs to 76 lbs. It's just a funny way to make comparisons, >>> unless you are trying to purposely minimize accomplishment. >> >> >> I.ll leave aside Mark.s point, I don.t know enough to agree or disagree. > > But Darren, your notion of percentages as a bad thing is just wrong. >> >> >> Lets say I earn $100 an hour. Then I get a $100 raise, am now earning > > $200 an hour. >> >> You are earning $1000 an hour, and then you also get a $100 raise. So > > you are at $1100 an hour. >> >> >> We both get an added $100 an hour, but my increase was 100%, yours was > > only 10%. Don.t you think that percentages better reflect the perceived > value in this case? Ask the buyer of a new $20,000 car how important a $2000 > discount would be. Ask the buyer of a new $100,000 car how important a $2000 > discount would be. >> >> >> There is a long history of trying to use numbers in various forms to > > represent perceived value of one sort or another. Most systems fall apart > because our underlying value systems are not linear and cannot be fairly > represented with a simple linear scale. Percentages do a pretty good job > capturing some of that underlying non-linearity and I think Mark.s usage > helps to provide a valid alternative perspective on this "breaking news.. > Log scales can be another useful tool. >> >> >> stan > > > -- > PDML Pentax-Discuss Mail List > [email protected] > http://pdml.net/mailman/listinfo/pdml_pdml.net > to UNSUBSCRIBE from the PDML, please visit the link directly above and > follow the directions. -- PDML Pentax-Discuss Mail List [email protected] http://pdml.net/mailman/listinfo/pdml_pdml.net to UNSUBSCRIBE from the PDML, please visit the link directly above and follow the directions.
