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Cage
10-11-2010, 9:03am
I've been thinking about the evolution of cameras and lens, particularly in relation to the rapidly improving high ISO capability of the modern DSLR.

Not too long ago, anything over ISO 200/400 was going to give you a grainy result.

To combat this, lens builders gave us bigger apertures in our lens, and when this was done with a telephoto lens, it resulted in some monstrous contraptions.

With most manufacturers now offering bodies that handle ISO1600 and higher, with little, or nil discernible noise, will there still be a pressing need for the 50mm/f1.4 or the 500mm/f2.8?

If technology has picked up four or five 'f' stops, in camera, will it not follow that the need for big aperture lens is over?

Or am I missing something in the exposure equation? :confused013

Cheers

Kevin

mpb
10-11-2010, 9:09am
Getting a shallow depth of field would be lost/reduced if we did not have these larger apertures.

maccaroneski
10-11-2010, 9:19am
Yeah aperture is not all about getting as much light in as possible - try getting nice bokeh at f9.

Cage
10-11-2010, 9:29am
Aha, DOF.

I knew I was missing something.

Ta.

Kevin

James T
10-11-2010, 9:53am
Not to mention focussing speed, focussing accuracy and being able to see through the viewfinder at night. ;)

ving
10-11-2010, 9:58am
and also not to mention looking like a complete and utter photo pro by carring around a lens with a massive front element!

Cage
10-11-2010, 10:02am
and also not to mention looking like a complete and utter photo pro by carring around a lens with a massive front element!

:lol:

Bercy
10-11-2010, 10:13am
SOme things are additive as well. Coouple fast glass, decent high ISO and anti-shake technologies and you should be able to take a crystal clear picture in the moonlight!

etherial
11-11-2010, 9:10pm
The other night I was shooting an indoor dog event where you really need to keep a fast shutter speed (distance too far and action to fast for good flash work). I was shooting f2.8 and ISO6400, I need every stop I can get!

(Pics turned out ok, still not fast enough but acceptable all the same :))

Othrelos
10-12-2010, 1:35pm
I hate to say this, but ever since the advent of AF lenses have become slower because the need for faster lenses and the brighter viewfinder they give is substantially reduced amongst your average photographer. The brighter viewfinder made manually focusing much easier however since AF became commonplace such a thing became, seemingly overnight; much less of an important factor. Ironically it can be extremely difficult to manually focus a fast lens on the modern stock focusing screens* that are commonly sold with DSLR cameras. Often third Party focusing screens are required for precision manual focusing, with the drawback that they can foul up the camera's metering and in some cases, completely void your warranty.

Higher ISO's do give the benefits of faster lenses with fewer drawbacks. However there is a limit, no matter how high ISO you can use if the lighting isn't good, you are still going to get a bad image. Audio recordists have a saying "crap in, Crap out" the same applies for photography.

As for me, I use the fastest lenses I can get my hands on (I have the bank balance to prove it) I use the lowest ISO I can to maximise image quality. though of course others are more prepared to sacrifice image quality in order to capture an elusive moment, each to his own.

* It is possible to do this but your average photographer wont have either the time, nor patience, to develop such as skill. Manually focusing a Noct Nikkor 58mm f/1.2 on a D3s is a challenge few will ever face.

Dylan & Marianne
10-12-2010, 1:39pm
I'd absolutely love to have a 1.4 lens for the weddings that I do !
Mind you, the high iso for the reception would also be good.
They are two similar issues yet different.

old dog
10-12-2010, 2:34pm
yes, depth of field is the clincher. I`m looking forward to using older lenses with not so fast an aperture (when you don`t need a shallow DOF) as the high iso performance will provide faster shutter speeds. Where`s my D7000???....want one..:(

TOM
12-12-2010, 8:29am
i am only guessing here, but i suspect that the catalyst for most people's desires to upgrade their camera, is better ISO performance, when the most logical step would be to upgrade to faster, better glass.

JM Tran
12-12-2010, 9:34am
i am only guessing here, but i suspect that the catalyst for most people's desires to upgrade their camera, is better ISO performance, when the most logical step would be to upgrade to faster, better glass.

hehehehe, a bit like buying a performance car and whacking economy tires on it - aint gonna handle very well at all!:)

farmer_rob
12-12-2010, 11:38am
i am only guessing here, but i suspect that the catalyst for most people's desires to upgrade their camera, is better ISO performance, when the most logical step would be to upgrade to faster, better glass.

Obviously, a lot of this depends on what you are photographing, but better glass introduces DOF complications - another current thread is talking about using a 200mm f/2 lens (http://www.ausphotography.net.au/forum/showthread.php?73458-Nikon-200mm-F2-user) for indoor events, but wide open, the DOF is too thin. (I also think that better technique and more care fixes more sharpness issues than either a new lens or a new camera.) Finance is also an issue - in some cases, you get more "bang for the buck" out of a new body vs a new lens.

BTW, as I have posted elsewhere, my own desire for an upgrade was more related to AF and body issues rather than ISO (and I've yet to really outshoot my existing lenses :o)).

peterb666
12-12-2010, 12:24pm
Yeah aperture is not all about getting as much light in as possible - try getting nice bokeh at f9.

Unless you are shooting ultra long, there won't be much in the way of nice bokeh at f/9. On the other hand, f/0.95 is a completely different story.

TOM
12-12-2010, 1:45pm
but better glass introduces DOF complications

better [faster] glass gives you more options, i don't see how it introduces more complications.


you get more "bang for the buck" out of a new body vs a new lens

that may be true in some instances, but i think it's a rather short sighted solution.


shot with a 1.4/75mm @ f9.5

63962

peterb666
12-12-2010, 4:31pm
Christmas is fast approaching so it may be a good time to ask Santa for a fast lens.

http://farm6.static.flickr.com/5201/5200660895_bc6e3361b4.jpg (http://www.flickr.com/photos/23034038@N05/5200660895/)
The Office Christmas Tree 1 (http://www.flickr.com/photos/23034038@N05/5200660895/) by peterb666 (http://www.flickr.com/people/23034038@N05/), on Flickr

Olympus E-P1 with Voigtlander 25mm f/0.95 stopped down to f/1.4.

pollen
12-12-2010, 5:37pm
I think there's too many generalisations being made, for me personally, we have not yet reached a technological level where every photographer can get the shutter speed they need, yet have a totally clean file. 5 years ago, ISO 1600 was deemed as the "acceptable" level. Nowadays it's around ISO 3200. We haven't really made that much advancement at all. And for landscape and commercial photographers who need cleaner files, even ISO 400 is still too noisy. ISO technology has not really advanced at all.

That being said, aperture control, as others have pointed out, is still required irrespective of modern ISO capabilities.


Yeah aperture is not all about getting as much light in as possible - try getting nice bokeh at f9.

You can get nice bokeh at f/9. Here's an example at f/8 that I have handy, and I've seen similar at even f/16
http://dawei.zenfolio.com/img/s10/v2/p521265383.jpg


another current thread is talking about using a 200mm f/2 lens (http://www.ausphotography.net.au/forum/showthread.php?73458-Nikon-200mm-F2-user) for indoor events, but wide open, the DOF is too thin.

There is a lot of DOF at f/2 on a 200mm lens - because you have to stand so far back, DOF is quite huge. I've used it for indoor weddings and everything.

DOF is so large on a 200mm lens at f/2 that it can also be used for group photos. here's a group photo at f/2, 200mm:

http://dawei.zenfolio.com/img/s4/v3/p963165240-4.jpg

peterb666
12-12-2010, 6:00pm
Depth of field is going to depend on the distance the subject is from the lens as well as the aperture. Having a fast lens gives, as others have noted, provides more options. It also makes for a brighter viewfinder and makes it easier to focus in poor light. Of course, f/2 is very fast for a 200mm lens with most lenses of that length starting around f/4. Depth of field at say 1m isn't going to ge very useful (unless you have a relatively flat subject), on the other hand, at 5 metres you may have enough to work with (such as in a group photo) like the one above.

It is nice to have the options and it provides alternatives to working with longer shutter speeds and increased depth of field when you don't need it - as well as giving less image noise.

infl3xion
12-12-2010, 6:00pm
improve both so we get night vision :D

TOM
12-12-2010, 6:15pm
night time is best for mostly sleeping :)

farmer_rob
12-12-2010, 6:23pm
better [faster] glass gives you more options, i don't see how it introduces more complications.
OK - more options, but it may not solve the problem you have. And if you want/need f5.6 for your *desired* DOF, faster glass won't make a significant difference for the price. (refer to the thread I pointed at.)



that may be true in some instances, but i think it's a rather short sighted solution.


I did suggest in some cases, not all.



There is a lot of DOF at f/2 on a 200mm lens - because you have to stand so far back, DOF is quite huge. I've used it for indoor weddings and everything.

I'm sure it is a great lens with excellent applications, but if you refer to the thread I pointed out, you will understand why I am saying there are situations where the DOF is too thin, and hence the lens does not fit all the problems. (And, yes, there are too many generalisations - but I include "get faster glass" as a generalisation too.)

TOM & Pollen: Great shots BTW

Othrelos
12-12-2010, 6:33pm
As demonstrated by Leica photographers, never underestimate what can be captured in the available darkness of this world, Leica cameras can be hand held at substantially lower shutter speeds than traditional SLR based camera designs because they don't have that sharpness killing mirror flapping about. Though you don't really need a budget to support a Leica M9 and a noctilux 50mm f/0.95 to do low light photography, there are a few cheaper options that are as good. Pentax or Sony's offerings with decent intergrated body IS. Both Minolta and Pentax at one point produced 50mm f/1.2 lenses (pentax are apparently still making theirs) in combination with the IS in the camera bodies hand holding at 1/2 a second isn't such a daunting prospect. For slow moving or static subjects under low light, ISO and fast apertures aren't the only thing that has to be taken into account.

TOM
12-12-2010, 6:36pm
OK - more options, but it may not solve the problem you have. And if you want/need f5.6 for your *desired* DOF, faster glass won't make a significant difference for the price. (refer to the thread I pointed at.)

hey your two options here is to go with a slow shutter speed (it's a bit harder with an slr than most other cameras though) or ISO crankage, sure, but i'd love to have that fast option. distance is the biggest contributing factor for DOF of a given focal length, not aperture. at a moderate distance for any given focal length (say halfway between minimum and infinity), DOF isn't too much of a concern wide open.

Othrelos
12-12-2010, 6:58pm
Distance is the biggest contributing factor for DOF of a given focal length, not aperture. At a moderate distance for any given focal length (say halfway between minimum and infinity), DOF isn't too much of a concern wide open.

I don't disagree with your statement, however I will point out that DOF still can be quite shallow with f/1.2 lenses. Even at moderate distances, for instance on a D3s a Noct-Nikkor 58mm f/1.2 focused at 10m will have a total DOF of only 2.13m

kiwi
12-12-2010, 7:11pm
And 2.13 meters is enough dof for John Eeles lying flat, so, more than enough for most

ricktas
12-12-2010, 7:12pm
I don't disagree with your statement, however I will point out that DOF still can be quite shallow with f/1.2 lenses. Even at moderate distances, for instance on a D3s a Noct-Nikkor 58mm f/1.2 focused at 10m will have a total DOF of only 2.13m

I calculate that to 2.17m?

MarkChap
12-12-2010, 7:25pm
Over 2 meters DoF,
I would hate that to be how they measure the shallow end of a pool. :eek:

TOM
12-12-2010, 7:27pm
2.13m

actually less than that. the 2.13 or 2.17m is based on OLD film emulsion and OLD lenses, not modern Asph lenses with modern ag-x emulsions and solid state capture. if you wanted to print bigger than 8x10 and relied on those charts, you'd be pretty disappointed me thinks.

kiwi
12-12-2010, 7:28pm
Interesting though dof calcs like that, I don't believe that the sharpness is the same throughout that dof though that's not the theory

ricktas
12-12-2010, 7:34pm
Interesting though dof calcs like that, I don't believe that the sharpness is the same throughout that dof though that's not the theory

I agree, and I only use the chart as a guide. Not that I am going to measure my subject to make sure they are 2.17 metres. It gives me a general guide to work with

Othrelos
12-12-2010, 7:45pm
actually less than that. the 2.13 or 2.17m is based on OLD film emulsion and OLD lenses, not modern Asph lenses with modern ag-x emulsions and solid state capture. If you wanted to print bigger than 8x10 and relied on those charts, you'd be pretty disappointed me thinks.

based on a COC of 0.030mm 2.13m is what i'm getting for my DOF calculations. As far as I'm aware the vintage of a particular lens, or the emulsions used whether silver based or sillicon based sensors are variables that have a negligible effect on DOF. I have yet to be disappointed.

TOM
12-12-2010, 7:49pm
it's the COC that doesn't fly any more

Othrelos
12-12-2010, 8:08pm
it's the COC that doesn't fly any more

well it's a COC I still use with my full frame DSLR's and I haven't seen any particular reason to revise it, because I use DOF calculations to give me a ballpark figure of how much DOF I have to work with. Whether it is 2.13m or 2.17m I prefer to stick on the conservative side for my DOF.

etherial
12-12-2010, 8:10pm
Interesting though dof calcs like that, I don't believe that the sharpness is the same throughout that dof though that's not the theory

That's right, there is only one point that is the sharpest point in the middle of that quoted range for DoF calculators or charts. The range refers to an "acceptable focus or sharpness" which becomes subjective.

Anyway, this is wandering off topic. Bottom line it is horses for courses depending on your needs.

TOM
12-12-2010, 8:18pm
Cool, if you're happy with the results then there's no need to change.

pollen
12-12-2010, 10:21pm
I've never understood the point of DOF calculations for digital cameras, why not just use the LCD and DOF preview to check for the in focus area? It's far more relevant information than a theoretical calcuation. And where your camera doesn't have DOF preview, why not just zoom in on the LCD and check?

And if you don't have time to chimp, you certainly wouldn't have time to do a calculation!

Cage
13-12-2010, 9:45am
Thanks for all the well considered replies. :th3:

To me, it seems that the most valid reason for keeping the big aperture lens is to get enough light to the sensor to be able to focus accurately, albeit manually.

That seems to be an area in which the various manufacturers have room for improvement. Although I've seem some good feedback from KatzEye users, it only seems like a 'quick fix' and not a 'solution'.

IMHO, bokeh and DOF are always going to be a juggling act. Bokeh, particularly, seems to vary from lens to lens in similar scenarios, plus it has the potential to be 'adjusted' in PP.

Like most who frequent AP, I'm looking for information to help me get the best results from the gear I have. At times I feel like I'm on 'the trail of the Grail'.

Maybe I'm destined to wander eternally in the ever decreasing COC, never enough light to enable me to focus clearly on what I seek, eventually to disappear into my own fundamental orifice.

Cheers

Kevin

darkbhudda
13-12-2010, 1:58pm
For gigs I usually have to use my 50mm 1.7 at ISO 3200 and 1.7 because of the bad lighting. Sure in a decade when I can afford a camera with ISO 2.5million I won't need such a wide aperture for the low light conditions but the shallow DOF will still be useful.