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Friday, 16 October 2009


Ha....the days of nite High School football games with half the lights out trying to get good enough action shot to publish in the morning paper.....Tri-X pushed with acufine or HC110 replenisher.......and a prayer I might add...now you just get a new camera

Hi Guys, The Wise Ones,
It came over me all of a sudden, am I the only one around who finds the word 'bokeh' faintly unsettling. Can we not just say hey, really nice blur? Perhaps some more up to date person out there could enlighten me, the poor ignorant Limey stuck down in the far South West and totaly out of touch, as to the origens, Japanese maybe? and the compelling reasons for it's use. It has that feel of, 'hey, you really dont want to go in the 'Generic Nightclub' tonight, they are heavily into Bokeh down there and you will NOT be welcome!' People, I just thought I had to say this, but its not a big thing, please dont beat me up.

Ahh, the high iso thread. As a working stiff who shoots for a living, I have to say being able to walk into any lighting situation and make a photo is a wonderful thing. I was always an available light guy, even though I learned to use lights, and lots of them for certain jobs when shooting iso 100 slide film back in the day. My preference though has always been to keep a low profile and maintain my flexibility for framing. I'd rather see the light than make it.

I often am called to shoot stage action, like dance and music performances as part of what I do, and I have to say, a clean useable iso 3200 has changed my life. Especially when I have to make 30x40 inch prints! Life is good these days, we have an embarrassment of riches when it comes to what is possible, between high iso's, great lenses, and instant feedback.

What all of this new technology gives us at the high end, it also rewards us at the low end. I'm sure the brainiacs designing this stuff will heed the need for greater dynamic range and deeper bit depth as time moves forward.

If you don't want to buy it, don't. If you do buy it and don't want to use iso 100,000, then don't. Just like video, no one is twisting anyone's arm to use all of the capability that the cameras offer, but it's nice to have the option.

I thoroughly enjoyed this poll, post and thoughtful comments by Mike and Ctein. In particular, Ctein's links to his photos made me want to go right out and shoot some night shots, but, seeing as how we might get some snow tonight, I'll put it on my to-do list for a summer project. (My body doesn't stand up to the cold as well as it did in its younger years.)

Mike, I'd love to see more polls like this with analysis. Very good stuff.

Thank you Ctein. It is what you want to see or to portray. I don't see why someone should complain and say we don't need higher sensitivity. Just because they can't figure on using doesn't mean someone else won't. I for myself love all kinds of photography but alot of people produce very boring but very sharp pictures. I prefer interesting photos and i have greatly enjoyed some I have taken that show what I could have seen in the dark if my eyes where capable.

Mike, I didn't answer the poll because the answer for me depends on whether I'm buying a compact or an SLR, and the question didn't specify this. FWIW, my answers would have been 400 and 3200, respectively.

" Photography's never been merely about photographing what you could see; it's always been about photographing what you wanted to see. "

This may be the most apposite sentence ever written about photography.

Made doubly true by the Photoshop era, it still goes to show that getting it "in-camera" is always better!

Bravo, Ctein!

I just knew if I kept reading him long enough, I would read a Ctein column that I not only enjoyed but completely agreed with. (I've never not enjoyed reading one.)

I always shoot at ISO 200 except when I can't. Such as a small theater performance with almost no light. Or flying birds at the zoo inside the bird pavilion with a slow 300mm lens. Both shot at 6400 on my D700. Then outside and back to 200.


At least in my case I understood the question as being directed to the present situation. So NOW a good ISO1600 would be my minimum standard. A few years ago, it was ISO400. If the race goes on, though (and it will, at least for some time), I´m just fine with beautiful ISO100k and beyond, as Ctein is. Triple-hell, yeah!

"Bokeh" is a Romanization of the Japanese word for "blur," specifically (as used by Western photographers), out-of-d.o.f. blur, as opposed to motion blur or camera shake.


I have to say that I bought a Canon 5D Mark II specifically for the high ISO performance.

For landscapes I am an inveterate tripod user. I used to shoot night shots with color slide film. Not only the reciprocity failure but the always exciting color shift.

The other thing I love to photograph is live jazz performances. Some of the worst lighting conditions imaginable in smoky basement bars. All shot handheld with (un)available light. For this the ability to shoot at ISO 3200 and get a picture is a godsend.

Horses for courses.

I think it's worth noting that the poll had two questions in it (the title and the question proper), and that there's a third question that wasn't listed that probably implicilty influenced a lot of people's answers.

The first was ‘How Much Speed do You Need?’

My answer to this is ‘not much’. I'm sure I'd find a camera that only perfomred acceptably up to ISO 200 very usable - I've certainly gotten by okay with films slower than that. Sure, not being able to go higher would be limiting, but I'm pretty confident my basic needs as a photo hobbyist would be met.

The next question was ‘When you're shopping for a digital camera, what's your minimum standard for high ISO of good quality?’

My answer to this - the answer I gave for the poll - is ‘[about] 800’. This is because of my assumptions about the state of the technology. More speed is always good, but it's not my top priority. On the other hand, if a current camera can't turn out decent images at ISO 800, my question is going to be ‘what went wrong?’ I can live with less, as an abstract matter, but I'm not going to accept less (at least not without a very compelling reason) once I know where the established baseline is.

The question you didn't ask, but that some of us couldn't help thinking about, was ‘How much speed do you consider the maximum amount that's a selling point?’, or something like that.

My answer to this question is ‘how much have you got?’ More speed will always be able to open-up new possibilities we'd never thought of before, in exciting areas like, say, 1am suburban street photography. I don't know exactly what I'd actually use ISO 51200 for yet, but I'm sure that if my camera supported it I'd discover an application eventually, and that application would probably turn out to be a lot of fun.

"Digital sensors have better reciprocity characteristics" Hey Ctein, this may well be one advantage of digital, but what about long exposure sensor heat noise? I've done night photography on both film & digital & the digital camera images get uglier as the exposure gets longer. You can use in camera noise reduction but at least with Canon that doubles the exposure time, i.e. 10 minutes for the shot & another 10 for the camera to create a black frame to use to clean up the photo. Film doesn't have that problem, or do you have some way of dealing with this on your night exposures?

Speed (in lenses and film/sensor) equals options. Always has been, and will continue to be so. Options allow for flexibility and (hopefully) increased chances of success.

How about shooting 1/8000th at f/22 in daylight?

For PJ or other available light work, high ISO is a godsend.

One other benefit I've immediately noticed when photographing in dark rooms using high ISO with flash is that I can hold the background with color and details from existing ambient light. With high ISO, the flash acts like fill light, instead of a blast of white light in a dark cave.

"Partly because chroma noise isn’t an issue—"
actually chroma noise is a pain in the ass (pita). In Aperture when using the red filter with a Canon G10 at even ISO 200. Now i realize that this probably has as much to do with Aperture lacklustre implimentation of colour filters as anything. Nonetheless chroma noise in other wise fairly uniform blue sky results in a faithfull bw conversion to a nasty oatmeal consistentcy grey blotchiness when using that filter, orange is accepatable and yellow is fine. (the blue filter can be downright surreal!)

Knowing and using are two different factors.
For me it's KII which of course become K64 for most people.

Those ink black skies so familiar to Kodachrome users doing timed photography in the dark of night.

That was thirty years ago and these days nothing really appeals to my night photography wishes. I must be getting old!

A higher ISO rating would mean a faster exposure, but would it yield the same intense imagery?

Sort of doubt it. To me digital sensor response needs to explored far more deeply before any of us know exactly what can be accomplished!

Sure a high ISO is great for exposing those fast moving objects on rails at night, but is what we want or desire? As I said, what we want, what can be accomplished and what the result may be, are all different.

As one bloke said to me while I was doing night shots in the UK; an ancient battlement lit by the full moon...exposure sire? Two furlongs per fortnight, wide open!

I never thought of it that way, but you're right Mike ! I used to shoot my KM 7D at up to ISO 1600 as I considered ISO 3200 unusable (unless converted to b&w and only for certain subjects). I believe my Sony A700 to be 1 stop better with ISO 3200 results equivalent (in same size image, not 100%) to ISO 1600 on the 7D, but I still generally limit myself to 1600. I shoot a few more at 3200, but still maybe 1% (while ISO 1600 is easily in double digit percentage). And you're exactly right on the reason: high ISO gets more usable, but will likely never be as good as I want it, so I'll continue to make efforts to shoot at lower ISOs. Right now, I freely shoot between ISO 100 & 400 without concern; high ISO IQ would have to get to where ISO 400 is now before I'd stop making an effort to shoot slower.

On the subject of ever-increasing ISO ratings, there seems to be an implicit assumption that the numbers can keep increasing forever. Wait a couple of years and Nikon will have a D3si at 400,000 ISO, then Canon will leapfrog them, so the D3sx will need to boast ISO 1 million...

But, that can't happen. At some point the camera becomes 'perfect', and you bump up against the physical nature of light.

Such cameras already exist. I use one in my lab. It has a quantum efficiency of about 95%; meaning that 95% of photons that reach the sensor are detected - close to perfect. It has almost no dark noise; the sensor is cooled to -30 Centigrade. Neatest of all, it uses on-chip electron multiplication, so that individual photons can be detected with essentially no added noise. Thus, in terms of low-light sensitivity, it is as near perfect as makes no difference. (Though in other regards it is far from perfect - the resolution is only a quarter megapixel, and it costs over $30,000!)

But, all this does not mean you get noise-free images. There is still noise because of the quantal nature of light which arrives at the sensor as discrete photons. If only a few photons are hitting each pixel the statistical variation is large, resulting in noise that can only be improved (as a square root function) by getting more light onto the sensor. In that regard, fast lenses still have their place, and cannot at some point be replaced by sensors with higher ISO ratings.

What is the ultimate ISO rating is that would define a 'perfect' camera? I don't know, and the way ISO is defined makes it hard to figure out from first principles. Some day I mean to bring my Canon into the lab and see how it fares in comparison with back-illuminated, electron-multiplied, thermoelectrically cooled ccd perfection.

Chroma noise is less of a problem than luminance noise because you can reduce chroma noise more easily in post-processing in Photoshop. I know you can't do this sort of thing easily in Lightroom and assume the same is true in Aperture.

In the cited example, red channel noise in skies can be reduced by running a surface blur on the red channel on a separate layer in RGB mode, then switching to LAB color space and restricting the blur to areas that are sky colored (or just negative in the LAB b channel) using Photoshop's nifty Blend If control.

Other sorts of chroma noise can sometimes be dealt with using artful blurs of the LAB a and b channels that carry color information but not detail.

Luminance noise is harder to get rid of without sacrificing detail, but is more attractive.

Just a minor correction to Bryce Lee's comment on Kodachrome. Kodachrome 25 replaced Kodachrome II. Kodachrome X was replaced by Kodachrome 64.

Lee L

I had difficulty with the poll because of the question "for what?" I bought a 5Dii largely for zoo photography; I've figured out that pretty much the minimum necessary for me there is ISO 4000 - and in fact even at 25000, the top of its range and not very usable, I can barely shoot in the nocturnal area. (And even a slow loris is way too fast for long exposures.) For a walkaround camera that's mostly to be used outdoors or for snapshots, I don't really need anything better than good 400 and usable 1600. (So I bought an S90 for that.)

But I know exactly what I'd use a pristine ISO 100,000 for: macro. One of the revelations of the 5Dii that I haven't done much with is that in bright sunlight, I can jack the ISO up and shoot decent handheld macros with reasonable depth of field. The higher the ISO goes, the more light conditions that would be possible in, not to mention supermacro possibilities. I don't know where the top end of usefulness in that department goes, but it's very high. And the opportunity to shoot macro whenever you want to without a tripod opens up a whole new world of possibilities.

Dear Michael W.,

I simply haven't gotten into the range where long-exposure noise is a serious issue. As I said, nothing's yet running much more than a minute. With those time, the noise, at worst, is a very sparse scattering of "hot pixels" that are easily spotted out of the photo. As someone who works a lot with film scans, I am used to dealing with far, far worse.

Astrophotographers have it bad, but I ain't one of those, presently.


Dear Ian,

You've brought up a question that interests me. I *almost* know how to calculate the answer to it, save for one piece of data. I'm really terrible at doing photometric conversions, so I can't be sure of my numbers for the flux incident on the lens. If I had that, I could solve the whole problem.

To put it concretely, if I give someone the incident flux on a scene in photons/cm^2/sec, can they tell me the number of photons/cm^2/sec reflected by a 12% diffuse reflectance object at the lens? If anyone here will do that conversion for me, I can answer Ian's question, as to what physical 'perfection' means.

pax / Ctein

For people who take photos at concerts and sports events, high usable ISOs are great. So are F1.1 lenses. I suspect the market for both is similarly small. In reality, 100,000 ISO is there for the same reason that 0-60 in 4 seconds is there for a Ferrari - to make the manufacturer numero uno in a p***ing contest.

1600 gets me as much as I need at f:2 or 2.8 in a dimly lit restaurant, where a tripod may be impractical. 800 is often enough for streetlights. I suppose I might want crazy high ISO speeds if I shot dancers on stage or skateboarders at night, but I don't.

For me, the solution is pretty simple:
manufacturers should make a DSLR with exchangable sensors: for instance, for an APS-C seized DSLR, one should have a 15 megapixels, ISO 50 base sensitivity, with good quality up to ISO 400, and a 12 megapixels, iso 400 base sensitivity, with good quality up to ISO 6400.If you get out on a sunny day, you mount the first sensor in your camera. An ISO 50 base sensitivity will allow you to do panning in lot of light, for instance. If you want to take pictures of your son playing hockey or basketball, you mount the second sensor in your camera.
I know, my scenario is probably mere utopia, such a camera would cost an arm and a leg, but it's worth considering.

High ISOs can save energy costs. When a camera can be used at ISO 800 as a base ISO, you are decreasing the amount of light needed to reach a subject, in the studio this means when using hot lights, they become less hot and thereby decreasing AC costs, when using battery strobes less AAs go in the trash because the need to use the flash lessen but also because you can use lower power. In the end when camera makers are making higher ISO cameras they are in fact saving the world.

As has been said in these comments it depends on what you're photographing. My main thing is close ups at fancy dress pub crawls (they're never called this but here in Hastings, UK most events are seen as an excuse for a pub crawl) and ISOs should be dictated by aperture and shutter settings; in a perfect world I would use 125 @ F8 - F16, a bit of spreadsheet work tells me that to get ISO 400 quality (Canon 5dMk2) I would need ISO 12800 - 51200. The reality is 125 @ F1.4 - F2.8 leading to many shots with tips of noses in focus but eyes buried in the blur. Fortunately I still get a good number of "keepers" but I can dream...


The question being about "minimum" standard--not "optimum" or "desirable" or "best"--I think a bell curve response should not be surprising (though it would not be easy to explain why I think that--some combination of respondents' habits/needs, expectations, knowledge, and possible [mis]interpretations of the question).

I understood "minimum standard" to be the threshold of even considering buying a camera for my particular needs, barring some feature unique and compelling enough to consider less. For me, that's ISO 1600, with an implied expectation of usable, if not good, results at ISO 3200-4000.

This happens to coincide with my expectations of black and white film, which is what I most often work with these days.

Of course, more capability would be better and welcome, but that wasn't the question.

f/4 and 1/20 with monopod is something I´m looking for in concert halls, curches etc. So to me everything between ISO 800-1600 would be high enough.

Back in the days of Kodachrome II we used to take photos everywhere ! Today it`s hard to believe how we managed to do it with ISO (ASA) 25...

This is a very interesting discussion. What is striking is that one essential factor is left out of it by almost anyone of us: the final form in which we want to see our photographs. To take two extremes: do I want to sent the picture to be viewed by a friend on his cellular phone, or do I intend to make a large fine art print destined for display on a museum wall ? The range between these extremes is huge and most of us will fall in between. The kind of final output as well as someone's own standard for quality will be decisive factors when judging ISO quality. With a D3s body my answer for the two given examples would be 100000 ISO and base ISO respectively.

Another problem we face in our discussions is the generally admitted statement that it is the final print that matters, but not the 100% view on screens. To put it bluntly: I watched most of my pictures on screens. For over 30 years I projected slides on a screen and since switching to digital I enjoy looking at them on a wide LCD screen. In the future I hope to get a high quality digital slide projector. Only rarely did I ever make prints although I have all the necessary equipment to do so.

With enjoying digital pictures on an LCD comes a new dimension. Not only does one look at the entire picture in the 'fit screen' position, but one very much enjoys going into detail, that is having a look at 100% magnification. This is definitely not pixel peeping. For me the upper ISO limit is therefore reached when I do not like the pictures on screen at 100% magnification, that is when they become muddy, details come out as water colors and grain starts getting visible. My upper limit with the D700 is 800 ISO, although I sometimes use it up to 3200. I might go for a D700s should there be one, as I enjoy shooting with available light.

I was testing the S90 and GF1 at ISO 2000. I was amazed at how well the S90 did. Well enough that I am leaning to return the GF1. As cool and fun as the GF1 is and capable. I feel for what I would use a compact camera for the S90 feels better handling and is way more portable.The $500 + I save can go to another toy.

Ata recent conference I was sharing photographic duties using my Sony F717 with one other attendee who had a Nikon D300. The Carl Zeiss branded f2.0-2.4 zoom lens enabled me to use ISO 400. The Nikon user was shooting at ISO 1800. Yes, the Sony images had to be cleaned up with Noise Ninja, but we agreed that the F717 images were just as usable as the D300. How I wish that Sony had continued the Fxxx series with modern 2/3 sensors.

Hats off to Ctein. Great title, great sentiments, great aspirations, great attitude, great conclusion. Nevermind that he is half step away to figuring out this ISO perfection physics question - that's just scary. I'm thankful that he can convey all that understanding into language and enthusiasm that mere mortals can relate to.

It was an interesting poll for me, as I realised that my photographic needs evolve to meet the available technology.

Or in other words, I generally don't want more, but will always find a way to use it.

Four years ago, I would have considered ISO 400 to be my most usable speed. I now think ISO 800 is my most usable.

And despite that, I have taken shots at ISO 1250 or higher, because I was in very dark locations and couldn't (or didn't want to) use flash.

(But I tend to consider ISO 1250 my ceiling for most purposes...)

Why am I so conservative with my ISO?

Well, some might say it's because I use Four Thirds equipment. I'd beg to differ, but they'll say it anyway.

A friend of mine has a Nikon D700. He took some test shots on a dark night in London, at high ISOs. And he raved about its capabilities.

But when I saw them, I saw what I always see in high ISO shots. Too much grey, not enough black, and rather dull colours overall.

He pointed out the details in clouds, and raved at the sensitivity. I saw a sky that should have been black, windows that should have been black, and a sea of almost uniform greyness.

When I take "high" ISO shots - and this won't change regardless of manufacturer - I end up having to change the colour curves to get the blacks looking black, and that's perhaps just the start of what I'll need to do to rescue the picture. Colours may be too faded, and need tweaking - but high ISO often means poor lighting, which can mean a slight colour cast. White balance removes that, but then leaves some colours stronger than others, and I have to correct that too.

Noise removal? A couple of buttons. Easy. But getting the picture to look like it should, rather than having tonnes of grey detail and washed out colour? That's something I can spend far too long on, as I tweak a colour or exposure setting and then try to decide it that looks closer or further from my memory.

Interestingly, seem to manufacturers know this. Whether they call it Dynamic Range Optimisation, Shadow Adjustment Technology, or whatever - they are all introducing features which basically set a black point and then even out the colour curves a little.

It's as though with higher sensitivity comes an image that's further away from how we see, and closer to how a camera sees.
And that manufacturers have seen that, and responded with these new features like DRO.

If I had a mode I could turn on where the sensor saw colour at these higher sensitivities the way I see colour, then high ISOs would be usable to me.

And that's what it's all about for me. A usable high ISO.

What we have now is a high ISO that gets the picture, but then makes me do more work.

Barely usable.

But I'm sure that the future will deliver - after all, ISO 800 wasn't usable a few years ago.

Usability is no doubt marching ever towards me, just as history tells me that it's already arrived for ISO 800.

I ended up splitting the difference in my answer, because I tend to shoot at the lowest ISO possible, given the situation.

The single area that I really feel the pinch of an inadequate high ISO is taking pictures of people in dark settings where flash would be disruptive - parties, dances, restaurants, etc.

And there it is substantial - I have ended up accepting that such pictures will either be black-and-whites in the end (because of the color shifts) and/or heavily tweaked in RAW (time consuming).

If I could have a dark-fast mode just for those settings, I'd not need a high ISO, since everything else I shoot is outside and well-lit. In fact, I'd even like to see cameras devoted to such situations in their sensors and software.

(It's a bit like the high-dynamic-range question - most of the time the regular settings are perfectly fine - but there are those some-time moments where the camera just can't handle it.)

Looking at the ISO range of the D3s (effectively 100-100,000) I can't help but think how more useful an otherwise similar camera with the same ISO spread but over the range of ISO 6 to ISO 6400 would be.

Imagine being able to shoot fast glass wide open outside, because you were at ISO 6? You could even get some motion blur in that way instead of bumping up against the 1/8000 limit of your shutter. And daylight fill flash wouldn't need FP sync anymore. And you'd have a lot less need of ND filters to get water flow when shooting landscapes at ISO 6 since you're 4 stops slower than the current ISO 100 limit on most cameras.

Most people would end up with enough high ISO capability this way (ISO 6400 is plenty for most uses) and the new low ISO options could be major bonuses, particularly for landscape shooters.

Interesting columns although I kind of missed the lack of the high noon -part...

Night photography can be quite challenging, because things may move (e.g. due to wind, water) the light might change and night scenes with artificial light often have a rather high scene contrast. So one would need both a reasonably fast ISO (say 800) a fast lens and very good dynamics in order to get a good capture. Personally, I'm currently much more interested in dynamic range than noise, since the ability to capture a large dynamic range in one exposure permits all kinds of interesting things in post processing (and gives a bit of slack too if the exposure was slightly off...).

@ Ian Parker: You using a Roper Cascade II or Andor 887/897? I decided this week to order a second Andor. I think it's better than the Cascade II.

I answered ISO 1600 on the poll, but I wanted ISO 25600 15 years ago. I'm amazed at what I'm getting out of my old DSLRs pushing them beyond what they are supposed to be capable of.

No matter how good it gets in-camera, the folks who enjoy doing their own processing, and are willing to invest time and effort into that stage of creating a photograph will continue to push the envelope of the perceived limitations of the technology and materials.

"What I do today is simply shoot at the camera’s best ISOs, unless I can’t, in which case I shift to something higher. Doesn’t everybody?"

Not me, I tend to either use auto-ISO or have 400 as standard on M4/3 cameras and 800 on DSLRs (APS-C). Because in practice I can't see any quality loss, and it minimises risk of shake and so on.

In sunshine or if I want minimum DoF, I might set it lower.

By the way, recently I wrote the text below on my blog. Before I quote it, I must say your survey confuses me a little: the survey said only "How Much Speed Do You Need?", but now in this article you are saying "When you're shopping for a digital camera, what's your minimum standard for high ISO of good quality?" Now that's a different question. For me this is 800 or 1600. But the former, simpler question makes me react like: "as much as I can get".

[quoting myself below]
With the new pro Nikon camera, the D3s, Nikon has kept the 12MP resolution, but raised sensitivity to around 12,000 ISO. I applaud them for this. Personally I think higher resolution than about 12MP is for specialized situations, like really big prints (meter-big), but that we can use more low-light capability for a while yet. Why even in daylight outdoors, on a dull winter day here in Northern Europe, you pretty much need ISO 1600 for shooting with a telezoom (especially if it's not stabilized).

Funny enough, according to survey, 1600 is all most people say they need. I think it's up to what you're used to. It's not long ago that 400 ISO was the highest you could use in good quality, so we are still amazed at good 1600 ISO quality. The philosophical idea behind this, I guess, is that we just a bit more than we are used to, then we think we'll be happy. If we have a new level (of anything), then after a while we are used to it, and want a bit more. (We get used to higher levels faster and easier than lower ones.)

Dear Eolake,

I found it that the ISO curve from the poll seemed to mirror film development. Once the technology was there, filmmakers pretty quickly got to very good ISO 800 films and decent ISO 1600, but the efforts to go to a *true* ISO 3200 were few and far between and the films weren't very good at it. I know there as film technology out there, but the manufacturers didn't seemed inclined to develop it.

So maybe, in aggregate, tastes in speeds haven't changed as much as we think-- it's just that the new technology is satisfying a vocal minority in a way we couldn't previously?

pax / Ctein

Dear Calvin,

Truthfully, it's not a difficult problem, to a fair first approximation. Just counting statistics. Once I get a starting number, I could do it in a matter of minutes.

Getting a really accurate answer's a whole 'nother matter. That'd take me weeks. I wouldn't bother.

A related, non-trivial problem I'm interested in is the information bandwidth of lenses. I have this intuition it has substantial bearing on 'image quality' but no data to back up this intuition. May never tackle it, though; it ain't simple.

pax / Ctein


I know that Ctein knows this, but maybe other people don't--Kodak T-Max P3200 (created by Dick Dickerson and Sylvia Zawadzki and their team) is a 1000-speed film with a 2+ stop push built in to the processing recommendations. The "P" in the name stood for "push." The "3200" in the name was not an ISO rating.

(In fact, if I remember correctly, Kodak didn't seek or receive ISO certification of any of the T-Max films.)


I don't personally have any interest in the high value ISO figures being quoted. When I used to use digital with a Nikon D100 I was almost always at ISO 200 (its lowest setting).

Now I'm back to film it's either ISO 100 with FP4+ or Ektar 100 or Iso 400 with HP5+ or Delta 400 - Often these two will be used at EI 200.

Sometimes it seems that these high figures are just being used as a marketting gimmick a bit like the low end hi-fi and car stereo manufacturers who use an artificially high peak power output instead of proper RMS measurements.


I think I need to get this engraved on some marble bit.

I guess I answered the poll thinking "what sort of ISO performance would rule a camera out of contention", which for me was 800.

In other words, all else being equal, I would probably opt for a camera with better ISO performance if it were available, but unless a camera could produce acceptable (by my own subjective standards) results at 800, it wouldn't have a chance, regardless of its other features.

Actually, my real, everyday, requirement is for lower ISO - I could regularly use ISO 25 or even 12. Yes, I know I can use ND filters, but this is not always practical for some of the shooting I do. I think some people would be surprised how often my Canons are set to the "L" (faked ISO 50) setting, even when using telephotos.



I definitely want the interchangeable sensors. I want the dedicated B&W sensor -- no Bayer filter, so higher resolution (or, perhaps, a 6mp non-Bayer full-frame sensor?) AND more sensitivity (the Bayer filter blocks 2/3 light at each photosite, after all). Maybe use Fuji's tricks from the S5 for expanded dynamic range?

But I'm not holding my breath. Or screaming, or beating my hands and feet on the ground, either.

(And it's true that Canon made the astronomical 20D variant -- but they haven't made anything like that since then.)

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