Auto ISO ?

Gremlin

Gremlin

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On the last couple of meets I have been to it seems that quite a few people use auto ISO :shrug:
I don't, as good as the D300 is I still find that high ISOs will cause noise, so I prefer to play around with shutter speeds etc. and try and stay to 800 or lower.
What are your thoughts ?
It also seems that I use the camera in manual mode most of the time too :thinking: It doesn't have a mode dial so if you are a meet with me and ask what mode I'm using, excuse the blank look :D (ok so that's normal as is the inane grin)
My favoured setting is shutter priority and go from there, and yes I do use AF, spent far too many years on film doing the manual focus, so now opt for the easy life and my camera does a pretty good job to with the occasional help :D
 
I think the problems with auto-ISO are that a) it's unnecessary, as you can adjust it manually, b) it has quite limited range in practise - like 200-800ISO - before you hit noise problems, and c) we already have more auto modes than we know what to do with.
 
Gremlin said:
On the last couple of meets I have been to it seems that quite a few people use auto ISO :shrug:
I don't, as good as the D300 is I still find that high ISOs will cause noise, so I prefer to play around with shutter speeds etc. and try and stay to 800 or lower.
What are your thoughts ?
It also seems that I use the camera in manual mode most of the time too :thinking: It doesn't have a mode dial so if you are a meet with me and ask what mode I'm using, excuse the blank look :D (ok so that's normal as is the inane grin)
My favoured setting is shutter priority and go from there, and yes I do use AF, spent far too many years on film doing the manual focus, so now opt for the easy life and my camera does a pretty good job to with the occasional help :D
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Set it to Auto ISO (max 3200), set it to manual mode, set desired f stop, and shutter speed using the front and back command dials.

You can monitor the ISO in the viewfinder, if it starts getting too high for you, adjust shutter speed or aperture to bring down ISO

As for the D300 at high ISO

These were both at 3200, and with a TC on a 300 f4



 
I find that auto ISO is particularly handy when shooting, say, kids outside and you need to react quickly... I set my aperture and, if necessary, the auto ISO just makes sure the shutter speed doesn't drop below the minimum threshold I have set. I'd rather have a slightly noisy high ISO shot than a completely useless 'camera shake blurry' shot. Can't see any downside to using it TBH... :shrug:. The insane high ISO ability of the D3S means noise is rarely an issue anyway.
 
I use it for motorsport when using a Sigma 100-300 plus tc to keep the shutter speed and apeture the same :thumbs:
 
It's like just about every other 'feature' on a camera... sometimes it's really useful and sometimes you don't need to use it.

The Auto ISO on the 5DMKII is far more 'intelligent' than on the 40D and will default to ISO100 if the camera thinks it can get away with it. For landscapes and staged portraits, I tend to use ISO50 anyway if I can so the auto only gets switched on for stuff that's taken in a hurry (and yeah, I even use it at weddings)! ;)

Si
 
I think the main reason why auto ISO gets the shrug off from some is that it's a feature that not everyone is going to get good use out of due to what they shoot and also the quality of the higher ISO's available on their camera.

If your a studio dweller or a landscaper then auto ISO most likely is a totally redundant feature and that's fair enough, but trust me, it's a damn useful feature for some out there. :thumbs:

I love auto ISO and I'll explain why too!

For studio based or on location portrait shoots, especially involving flash I will always shoot in full manual but auto ISO is extremely useful in conditions that have rapidly changing lighting.

In general circumstances I find it equally as useful, especially when I need to work at the slowest handheld shutter speed I'm comfortable with and I want a specific aperture for effect.

But!.... for figure skating, auto ISO is unbeatable :banana: I imagine that it would also have a serious advantage in any indoor sport.

From experience I find that auto ISO allows an immense level of consistency between frames and since using auto ISO all the sequences I shoot in figure skating have identical exposure levels, allowing a faster post process under pressure.

Why wouldn't the exposure be consistent during a sequence anyway?
Well, fluorescent lighting flickers faster than the human eye can see, so if your not careful with your set up exposures will vary greatly during a sequence of shots.
This flickering effects white balance primarily but over the last three years of shooting figure skating I can safely say that it also has an effect on exposure, admittedly it is marginal but still, I'll have to slide the exposure level up in post on every third or fourth frame in a sequence and when taking thousands of images in a day you can imagine that that kind of individual attention to an image adds up on the time consumption department.

Shooting in full manual is of course possible, but all these folk that boast about shooting in manual only, as if it's the only way to have full control in any given situation, have, IMO, never been in a circumstance where you simply can't switch between settings fast enough or don't shoot very often under rapidly alternating lighting such as fluorescents.

Typically for figure skating, I set my aperture to 2.8, then set shutter speed depending on the quality of arena lighting, usually around 1/800th or 1/1250th for a well lit arena, around 1/500th to 1/640th for poor lighting and 1/400th to 1/320th for abysmal arenas.

Having an automated variable that does not effect aperture or shutter speed is simply golden ;).

The ISO sensitivity ranges from 1000 to 6400 usually and I set the threshold according to lighting quality. Poor arena lighting gets a lower ISO threshold and thus shutter speed will be lowered to compensate.

During competitions, skaters with darker costumes will have around -0.7 to -1 EV dialled in on exposure compensation and around +0.7 +1 EV for skaters with lighter costumes, again the variable being ISO and not aperture or shutter speed.

I also use auto ISO on my D200 to but I will set the ISO threshold much lower as the higher ISO's are a little ropey with that body.

Still, a grainy/noisy action shot is a winner over one than a shot with motion blur.
 
Another fan of auto ISO here.

Most shots I want to give priority to having a particular shutter speed and aperture combination therefore the ISO has to be such to permit that.
 
Tyke Tiler said:
I think the main reason why auto ISO gets the shrug off from some is that it's a feature that not everyone is going to get good use out of due to what they shoot and also the quality of the higher ISO's available on their camera.

If your a studio dweller or a landscaper then auto ISO most likely is a totally redundant feature and that's fair enough, but trust me, it's a damn useful feature for some out there. :thumbs:

I love auto ISO and I'll explain why too!

For studio based or on location portrait shoots, especially involving flash I will always shoot in full manual but auto ISO is extremely useful in conditions that have rapidly changing lighting.

In general circumstances I find it equally as useful, especially when I need to work at the slowest handheld shutter speed I'm comfortable with and I want a specific aperture for effect.

But!.... for figure skating, auto ISO is unbeatable :banana: I imagine that it would also have a serious advantage in any indoor sport.

From experience I find that auto ISO allows an immense level of consistency between frames and since using auto ISO all the sequences I shoot in figure skating have identical exposure levels, allowing a faster post process under pressure.

Why wouldn't the exposure be consistent during a sequence anyway?
Well, fluorescent lighting flickers faster than the human eye can see, so if your not careful with your set up exposures will vary greatly during a sequence of shots.
This flickering effects white balance primarily but over the last three years of shooting figure skating I can safely say that it also has an effect on exposure, admittedly it is marginal but still, I'll have to slide the exposure level up in post on every third or fourth frame in a sequence and when taking thousands of images in a day you can imagine that that kind of individual attention to an image adds up on the time consumption department.

Shooting in full manual is of course possible, but all these folk that boast about shooting in manual only, as if it's the only way to have full control in any given situation, have, IMO, never been in a circumstance where you simply can't switch between settings fast enough or don't shoot very often under rapidly alternating lighting such as fluorescents.

Typically for figure skating, I set my aperture to 2.8, then set shutter speed depending on the quality of arena lighting, usually around 1/800th or 1/1250th for a well lit arena, around 1/500th to 1/640th for poor lighting and 1/400th to 1/320th for abysmal arenas.

Having an automated variable that does not effect aperture or shutter speed is simply golden ;).

The ISO sensitivity ranges from 1000 to 6400 usually and I set the threshold according to lighting quality. Poor arena lighting gets a lower ISO threshold and thus shutter speed will be lowered to compensate.

During competitions, skaters with darker costumes will have around -0.7 to -1 EV dialled in on exposure compensation and around +0.7 +1 EV for skaters with lighter costumes, again the variable being ISO and not aperture or shutter speed.

I also use auto ISO on my D200 to but I will set the ISO threshold much lower as the higher ISO's are a little ropey with that body.

Still, a grainy/noisy action shot is a winner over one than a shot with motion blur.
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That's a great theory Tomas, and it's true that fluorescents flicker and change colour and brightness quite a lot, but...

If you have multiple fluorecents, I don't think that they flicker in sync. I'm not sure about that, but that's the answer I was given when I queried this in relation to fluorescent studio lights.

Anyway, that aside, the exposure level is set before the shutter opens, not in real time, so whatever stage of the flicker cycle was metered for, and set, it will be different for the actual exposure.
 
HoppyUK said:
That's a great theory Tomas, and it's true that fluorescents flicker and change colour and brightness quite a lot, but...

If you have multiple fluorecents, I don't think that they flicker in sync. I'm not sure about that, but that's the answer I was given when I queried this in relation to fluorescent studio lights.

Anyway, that aside, the exposure level is set before the shutter opens, not in real time, so whatever stage of the flicker cycle was metered for, and set, it will be different for the actual exposure.
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Intersting you mention that mate, I was once told by the lighting tech at the Euro champs that they do flicker in sync :shrug: although I struggle to fathom how.

I have no clue if they could and I agree it does seem quite improbable.

What I do know is that in three years of shooting skating events, some in very questionable arena's and then also some of the best in Finland, the results or irregularities are more or less the same:

During a sequence of shots, say 4 to 6 to 8 images, not only will the exposure vary, the white balance differs from a kind of 1: peachy tint to 2: a green/cyan and then 3: a more neutral balance.

It's always like this no matter the quality of the fluorescent lighting, the three variations are always apparent. I admit, this could be local to arenas in Finland but the Saku Suurhall arena in Estonia had precisely the same irregularities. Whether or not they use the precise same format or brand of lighting is another unknown.

True, this may could be caused by another event but it's certainly not my camera as I've used a Canon 30D, a 1DmkI, a 1DmkIII, a Nikon D200, a D3, a D700 and a D3s.

So, if I shoot in manual, ie, with a set ISO, set aperture, set shutter speed and set white balance, this variations (peach, cyan, neutral wb and exposure) are seen with intense regularity (although random) in all sequences.

Shooting with the ISO, white balance as a variable as in auto and keeping a constant aperture and shutter speed minimises the frequency and strength of those casts and exposure differences.

I may not be able to scientifically explain it but I sure know that the approach I use now is far more consistent and produces much more uniform results.

I'd post up some photos but were currently moving house and all my gear is spread out between three different locations :'( I don't have my skating archives with me.

Any ideas or thoughts?
 
They do flicker in sync, it causes a stroboscopic effect on rotating machine parts and makes them appear stationary..

As an electrician I spread lighting over three phases (if available) to cancel out this effect, or a row of florescent can be supplemented with lighting that doesn't flicker like halogen...:)
 
Cheers for the info John :thumbs:, Your explanation sounds very similar to the Finnish lighting tech at the Euro's, he also described there were two types of lamp used in Scandinavian arena lighting, I can't remember the names :thinking:
 
The syncing flickering thing. I really don't know, though Joxby seems to. They flicker in cycle with the mains frequency I think, so I can imagine that maybe if they're all hooked up the same and from the same power supply, they would flicker in perfect sync. In that case, the exposure and colour variances you're seeing would not only seem likely, but impossible to avoid at high shutter speeds. I know when I've tried it (ancient kitchen underlights) the variance was horrendous on both colour and brightness, and it also varied down the image, again as you'd expect with different parts of the frame being exposed to different parts of the cycle.

Then again, if they can be linked out of phase as Joxby suggests, that would cancel out and balance the difference. And it wouldn't surprise me at all if different types of fluorescents and old/new tubes are significantly different in this respect. I just don't know. When I posed the question before, it was in relation to those cheap ebay home lighting kits with three or four giant curley tubes. They must find a way of knocking them out of phase or they'd be useless.

But all that is aside from the OP. What I don't understand is how auto-ISO can adjust for this effect, bearing in mind that the exposure is read and set before the shutter opens, and is therefore reading a completely different cycle and at a different moment in that cycle, in phase or not.

I don't dispute your findings for a moment Tomas, just what's actually happening.
 
I dunno about eddison screw & bayonet lamps that fit in ordinary domestic bedside light type fittings, I think they will be flickering with the supply frequency.
Compact fluorescent light fittings can be bought with high frequency control gear in them, compact fluorescents are generally commercial lights, they have pins and push in to sockets.
High frequency tubular flourescents are also widely available, I have some studio light panels with 2ft 5500K tubes in and a light table with 4ft 5500K tubes, both high fequency, I also have a small portable light box that doesn't and its a right pain in the arse.
So the answer is, high frequency luminaires...:)
 
HoppyUK said:
I don't dispute your findings for a moment Tomas, just what's actually happening.
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I getcha ;) I'm no expert but since my method has changed the results have improved significantly.

Is auto ISO the cure? Not solely no but it's vital piece of the remedy.

Your right about the effects or variations changing when higher shutter speeds are used, the changes make for the better though as a slower shutter speed tends to blend the variations rather than separate them, it looks effin awful.

Iirc 1/1250th proved to have a much higher yield of notable variations in white balance if white balance was fixed.

My D3 has a rather decent amount of fluorescent presets, there's around 8 I think, I'd usually pick the closets one to the arena lighting and then customise it slightly, usually adding a few clicks of magenta.

A fixed white balance caused the peachy and cyan tints to be far more notable, but thankfully one year I got talking to a shooter from Reuters and he told me how auto white balance was a very clever choice due to the flickering flouro's.

To be fair I was quite stunned and I scoffed at him, I'd always been warned against auto but I tried it to prove him wrong and I got the most consistent white balance during sequences than ever before. (Provided shutter speed was fairly quick, ie approx above 1/640th) :shrug:

So this is why auto ISO is a huge benefit for me shooting under these oddball flouro's, I can keep my 2.8 aperture constant to keep the desired depth of field and I can fix my shutter speed to minimise or control the variations in the lighting more efficiently.

I have no idea if this, if you can call it a theory, is correct, there could be other events at play but in regards to the OP, if I take auto ISO out of the recipe, consistency goes straight down the pan.
 
HoppyUK said:
I think the problems with auto-ISO are that a) it's unnecessary, as you can adjust it manually, b) it has quite limited range in practise - like 200-800ISO - before you hit noise problems, and c) we already have more auto modes than we know what to do with.
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Sorry Hoppy but i have to disagree with you, shooting sports in rapidly changing light Auto ISO is brilliant
 
I think as others have said it very much depends on your type/subject you choose to shoot.

I use it a great deal as I tends to have to shoot varying lighting conditions and need to be quick, one Min I may be shooting into bright light and the next into bushes and shrubs where the light has changed dramatically. I don't have time to faff about checking histograms as there is a good chance the target would have scampered away.
 
Rovers_Andy said:
Sorry Hoppy but i have to disagree with you, shooting sports in rapidly changing light Auto ISO is brilliant
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Yeah, I can see that. Fair comment :thumbs: Just that there are usually other ways of doing it and ISO tends to be the third option.

But for sport or somewhere you don't want to change shutter speed or f/number (or more likely because you are backed up against the buffers and perhaps can't change them) seems like a good solution :)

And it works for Tomas too.
 
Wildlife with long lens.

Shutter speed needs to be high.
F number dependant on the effect you want

Auto ISO,superb in this instance.

Example.

Female marsh harrier flying below the skyline with a dull background, your at ISO 1600,1/800sec and F8 tracking the bird.The male arrives above her, the female swoops up to collect the prey from his talons, both are now above the skyline, the action is that fast that you simply don`t have time to change settings. The auto ISO kicks in,drops to 200 and will increase the shutter speed if necessary. As she or he drops back down from the bright background, the auto ISO changes accordingly, increasing to a max that you set.

Works well in some situations,IMO. But, I accept that it is not always good and sometimes do turn it off,landscape for instance.
 
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