Forum Replies Created
thanks David, that's what I was looking for but I'll have to check it on my large monitor to know. they look close on my Mac Air
Now what if you just left it @ 160 and ETTR for a stop or two it might be even better…
David Farkas;1246 wrote: Alright… here's the test:
Testing methodology:
M9 with 35 f/2 ASPH on tripod shooting into open shade. I first shot 1250 ISO at 1/125th @ f/8 (proper exposure) then changed ISO to 160 at the same shutter speed and aperture.
Imported into LR 3.5 using my standard M9 preset, synced the WB on both shots to 5400K +12 tint. Boosted exposure slider to +3 on ISO 160 shot. Exported to web sized and two 100% matching crops.
ISO 1250
Full image
100% crop – please click for full size
100% crop – please click for full size
ISO 160 – Pushed 3 Stops
Full image
100% crop – please click for full size
100% crop – please click for full sizeHere's my take:
ISO 160 pushed three stops looks better than I expected it to. It does pick up a fair amount of contrast vs. the straight ISO 1250 shot, but this can be tweaked in LR to match if so desired. The 1250 shot definitely has an edge with regards to noise, though. So, the theory doesn't pan out 100% in reality…. but it is pretty close. Make sure to click on the thumbnails for full sized images.
David Farkas;1239 wrote: Not sure if this translates to real world results. An easy test would be to shoot a test target at ISO 160, underexposed 3 stops and at ISO 1250 properly exposed. Boost the ISO 160 shot 3 stops in LR and then compare. Without doing the test (yet) my guess is that the 1250 shot will look better. If I get a few free minutes today, I will do the test with an M9 and an S2.
was going to do that too this weekend, but you have more cred, so please do
also, try 160 and ETTR a bit too…
Oh Boy, theory meets reality
Remember; …in theory, there is no difference between reality and theory…
OK, this is what I mean;
http://sensorgen.info/LeicaM9.html
wish I could upload it to make it easy but it seems that this site wont take reasonably sized attachments… or maybe I'm screwing it up. In any case;
you can see that raising the ISO of an M9 compresses DR and does NOT decrease read noise. That it is a CCD is not the issue, read noise is. Further, as ISO increases, saturation decreases (makes sense of course)
the implication here is that the M9 is also an ISO-less camera. Increasing ISO is actually deleterious to image quality from compression. One is better off nailing ISO at 160 and shoot using the stop or speed one needs for a given shot. Or, if it doesn't matter, just ETTR as much as you dare. The resultant underexposure, if present, can be upped in PP.
I just wonder how the S2 works… no data yet.
David Duffin;1225 wrote: Of course the shutter must activate to capture a raw for analysis — do you envision this action being assigned to a function button?
what a wonderful idea! 😉
How about a true RAW histogram that actually tells us what we are shooting pre-shot?
I assume most here use RAW/DNG wherever possible. I am further assuming that the current histogram is for a .jpg deriviative not true RAW
stephan;1219 wrote: The sensor-type (CMOS or CCD) is more relevant for the noise-type than the processor. Leica uses CCD-sensors that have other characteristics than CMOS used in 35 mm DSLR.
And even with CMOS-sensors the noise is increasing with higher ISO, but not as sharp as with a CCD.
Compared, for example, and starting wirh 100 ISO, the S2 behaves almost the same at 200, 400 iso, compared to a Nikon D3x, the spread increases rapidly from 640 ISO upwards. I would say from experience that 800 ISO with the S2 compares to 1200-1600 ISO on the Nikon D3x (and maybe 3200-6400 ISO on a D3S).
Also, resolution and post-processing is an important factor.
btw, ISO-Quality is not a question of S/N-ratio, it is more a stastistical problem of missing and eraticcal data. This is why a CCD-sensor with a lot of pixels can be as good as a CMOS-sonsor with less pixels (up to a certain level, though).
thanks for a reply but perhaps I could understand you better;
First Emil Martin of U of C fame has published a set of curves that plot ISO vs noise here; http://theory.uchicago.edu/~ejm/pix/20d/tests/noise/noise-p3.html#ETTR
and here is a discussion concerning particular cameras and how read noise and ISO effect final S/N; http://www.luminous-landscape.com/forum/index.php?topic=56906.msg460646#msg460646
So for my new Sony A-77 ISO setting is not terribly relevant, Just keep it @ 160 and push the histogram. But I'm wondering about considering the curves in that second reference, what does an S2 or M9 curve look like?
Or do CCD's produce a different family of curves? In which case, what do they look like and do we benefit more from ETTR or just follow the ISO? If so, where do we max out?
Also, when you say ISO is not about S/N but missing or erratic data, well yes the missing data is the problem but isn't the result more noise/less picture data? Or is there more?
Sorry to ask such complex questions but I want to get the most out of the camera's range
constable;1194 wrote: i am sure it must be simple
Ed
Leica and “simple” do not go together…
Pete Walentin;962 wrote: As I am one of them I could say this is the kind of attitude a lot of Germans have. It is the total opposite of what the general US American attitude is. Very, very direct. But it would fill a whole book to write about this and whats good and whats bad about it. What I do like about it is that I got a definite answer and do not have to read between the lines. Which is maybe much more friendly but could be unclear.
Sorry for the detour – back to topic. :rolleyes:
Well, as I said, they are typically correct. Just that sometimes the attitude gets in the way. As a person who uses German cars (Porsche, MB, BMW), cameras (S2, M9), and lasers I find their “Pride of Engineering” quite reassuring on the whole.
Right, back to topic…
woodyspedden;915 wrote:
Saying that the solution is to buy another system that has this accessory is a new high of arrogance, even for Leica. Germans are often misunderstood when they speak English because the language (German) is not full of subtleties but rather brusque.
Ummmm… well I work regularly with German and Swiss engineers and have had many opportunities to interface with them, both in English and their native tongue
I would politely disagree. They mean to be that arrogant. It has to do with a certain sense of their past and perceived destiny. Leica cameras are expensive, but relatively small ticket compared to laser systems. German designers/engineers are simply that arrogant. I have even made suggestions on equipment and been met with similar replies, only to have them come out with the improvement soon after having them tell me it “wasn't needed”. So I knew it was past the planning stage when they rudely shot me down. They just have “that attitude”.
Just is, in my experience. And like it or not, often they are right…
I have a different problem with my 58;
It starts to develop a mind of its own and starts flashing, seemingly randomly. Problem is that unless I have it on my Quantum battery it is discharged when I go make a photo.
it will happen intermittently and disappear as quickly as it comes on.
yes, I know it makes “test flashes” from time ot time but this is different, high powered discharges.
anyone else see this?
