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So long as you don't overexpose Stephen, that's true. And in fact, the Oly sensors are pretty good at recovering highlights so you're really just exercising that feature!
Absolutely! That is why it's so important to get the exposure right in camera.
Stephen
A camera takes a picture. A photographer makes a picture
this is an advantage of ISO100 vs ISO 200, the disadvantage is less DR.
I think the differences in that comparison are mainly down to the in-camera jpeg engine. It would be interesting to see the raws from a similar test - I might try to rig up a similar test.
Maybe but the conclusion of IR is: <This is because RAW data is cleaner at the expanded LOW ISO setting so the camera applies less noise reduction, better preserving subtle detail, particularly in the red channel>,
otherwise Olympus has totally different Jpeg engine at ISO 100
This is interesting thanks for posting. I'm quite surprised that noise is lower at ISO 100 because I always thought that the best ISO for noise was the base ISO.
Does anyone know by how much DR is effected by using ISO 100? If it's only like 0.2 ev then it's not something I'd worry about, but if it's drastic I'll stay clear. I can't see it being any less DR change than going from 200-400 though?
The only way to see if the effect affects or suits a person is by that individual trying it for themselves. What is sauce for the goose means the gander's cooked, or something like that!
Stephen
A camera takes a picture. A photographer makes a picture
Does anyone know by how much DR is effected by using ISO 100? If it's only like 0.2 ev then it's not something I'd worry about, but if it's drastic I'll stay clear. I can't see it being any less DR change than going from 200-400 though?
It is likely to be exactly one stop, (let's guess 12 instead of 13 DR gateaux)
as the Jpeg is formed by using one stop darker information from the same RAW file.
Do not be fooled that one stop of DR is a major incident ... it is still likely that most of the wanted highlights are retained on these modern sensors.
There was a period when ISOlow (and fake ISO100) disappeared from Olympus' cameras : terrible for me but most folk didn't notice.
That's odd - here is a test from DPReview of the E-M1 which shows the contrary (and expected) result:
I have to say I'm deeply suspicious of DxOMark results. Their "perceptual megapixels" measurement for example is guaranteed to make any u43 or 4/3 lens look poor.
That's odd - here is a test from DPReview of the E-M1 which shows the contrary (and expected) result:
I have to say I'm deeply suspicious of DxOMark results. Their "perceptual megapixels" measurement for example is guaranteed to make any u43 or 4/3 lens look poor.
Interesting. The joys of conflicting info. This makes more sense though, except for if the bottom axis is EV then they're saying that the EM1 only has a DR of 10ev (-6 to +4)?
I think that DR measurement is sensitive to how it's done so far as determining an absolute value for the spread. In particular it depends on where you draw the line on the lowest black setting. Different people will chose different criteria. DPReview choose 2% luminance. Since the curve starts flattening out in this part of the graph, choosing a lower value such as 1% will result in a big change in the lowest EV - bingo, larger DR value.
However, for the purposes of measuring DR change with ISO, the absolute value is less important than the difference. And of course, you can see from the DPReview graph that the line shape in the highlights is quite different - at ISO 100, we reach clipping (off the scale) at lower EV.
I'm not sure how DxOMark do their test, I must look it up.
Looked on the DxO web site, but this is all they have to say about their DR tests (which seem to be done combined with noise tests):
The light box (placed behind the target) is composed of two fluorescent daylight spectrum tubes with a diffusing sheet on top, achieving a perfect uniformity on each filter. The luminance is about 1500cd/m2.
We use filters having different light absorption levels ranging from 0% to 99.99% in order to test across a dynamic range of 4 density steps (= 13.3 f-stops — a dynamic range much greater than today’s digital cameras). When shooting such a chart, the sensor of the camera being tested sees a wide range of light levels, with a 1/10,000 ratio from minimum to maximum. For comparison, a printed target dynamic is typically 2 density steps (6.65 f-stops), which is inadequate to simulate high dynamic range or back-lit scenes.
Each uniform zone on the chart (a “patch”) is measured for luminance (cd/m2) with a certified luminance-meter; then all the values are input into DxO Analyzer software.
Once we measure the target and calibrate the DxO Analyzer software, the selected camera shoots an image of the noise target at different ISO settings, and we measure the noise for each color channel of the target image (R, Gr, Gb, B). We compute the mean gray level and noise values for each patch and for all images shot at different ISO settings. We then interpolate these numerical values for all gray levels to calculate and plot signal-to-noise ratio (SNR) curves, from which DxO Analyzer extracts the SNR 18%, the dynamic range, and the tonal range.
Oh, and I checked their E-M1 test too in case the mystery of better-DR-at-ISO-100 is something specific to the E-M10. Well, it isn't - they are still saying the E-M1 delivers higher DR at ISO 100. I simply don't believe this result - it's the opposite of what all other testers have found, the opposite of Oly's own positioning, contrary to the experience of users and inconsistent with the theory.
Looked on the DxO web site, but this is all they have to say about their DR tests (which seem to be done combined with noise tests):
Oh, and I checked their E-M1 test too in case the mystery of better-DR-at-ISO-100 is something specific to the E-M10. Well, it isn't - they are still saying the E-M1 delivers higher DR at ISO 100. I simply don't believe this result - it's the opposite of what all other testers have found, the opposite of Oly's own positioning, contrary to the experience of users and inconsistent with the theory.
What language is that quote?
I don't believe it either, looks like they've just continued the line rather than measured it?
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