Shutter Speed for Hand Holding Zoom Lens

[Peter Ryan]

I am locked in a debate with a friend about the minimum shutter speed you need to hand hold a zoom lens without camera shake. I know we have vibration reduction to consider, the shooter's age, whether we have been drinking the night before, sensor size, etc, etc.

If we take the basic premise that you need at least 1/focal length as a minimum shutter speed to hand hold a lens without camera shake then if you have a 18 –200 mm focal length lens AND we are shooting at the 18 mm end, what is theminimum shutter speed?

Is it 1/30 sec, as this is the next shutter speed above the basic rule of 1/focal length (18 mm); OR

Is it 1/250 sec as this is the next shutter speed above the basic rule of 1/focal length where you have a 200 mm maximum focal range to your lens?

[DoesNotFollow]

The 1/focal length guidelines apply to whatever the current zoom is set at. In your 18mm example (on a 18-200mm zoom), the shutter speed should be set to 1/20 (or 1/30 for the next full stop). You would need 1/200 (or next full stop of 1/250) only if you were shooting at the long end of that lens.

This being said, the 1/ rule is only to minimize camera shake. To completely eliminate hand-held shake, you need be at anywhere from 3-5 times the suggested speed. (This may be where a consideration of 1/250 at a focal length of 18mm comes from, it just so happens that it is near 1/the long end of the zoom.) Of course, VR or IS would allow you to shoot relatively slower at any focal length.

[Peter Ryan]

Thanks Jon. My thought process goes that if I had a 20mm lens it is very light and hence the 1/20 works fine but with a 18 - 200mm lens then the weight of the lens is much heavier than the smaller 20mm lens and would require greater stability or a faster shutter speed to hand hold without camera shake. I am of the belief that you need to work off the longest focal lenght in the zoom range when choosing an approritate shutter speed. My friend is of the same belief as you.

[Colin Southern]

with a 18 - 200mm lens then the weight of the lens is much heavier than the smaller 20mm lens and would require greater stability or a faster shutter speed to hand hold without camera shake.

If anything, I think this would work the other way; the heavier the lens (for a given focal length), the more resistant it is to acceleration due to a given force. Would you rather push a bicycle or a car?

[Peter Ryan]

I can see I am not winning this debate with my friend.

[Donald]

I's like to suggest that the issue is not related to the focal range of the lens nor to its size and weight, but to the field of vision and the impact of any shake that might be present. At 18mm you're covering a wide area. The impact of any movement is going to be minimal. But go to 200mm and have the exact same amount of shake - the impact of that is going to be much greater, because you're homing in on a much narrower field of vision. So the area you are capturing relative to the amount of shake, is much, much less so is therefore exaggerated. Hence the shutter speed needs to be much faster.

[Peter Ryan]

Donald I can understand what you are saying. It makes sense and it appears I will have to discuss this further with my friend, which I don't want to do but feel I must.

[MrB]

If anything, I think this would work the other way; the heavier the lens (for a given focal length), the more resistant it is to acceleration due to a given force. Would you rather push a bicycle or a car?

But muscles have a greater tendency to tremble when they have to work harder!

Philip

[Dave Humphries]

Hmmm,

I can see both sides of the argument about weight of a bigger lens being a good/bad thing.
I wonder what the answer is?

Here's a (fun/educational?) test for anyone/everyone to try.

You'll need a camera and lens that can zoom to the equivalent 35mm focal length of 200mm on your camera
A test weight of 500g, say a pack of margerine/butter, or one pound (16oz?) if you still measure in pounds and ounces in your locale (don't choose anything valuable!)
Something to hold that in; carrier bag with handles, something you can loop over the end of the lens
Somewhere private to shoot an out doors target (that is level with you) from (through an open window)
(We don't want to be seen doing this )

a) Put on a lens that reaches 200mm equivalent 35mm focal length on your camera
b) turn OFF any image stabilisation - IS, VR, VC, SuperSteadyShot, whatever it's called
c) set zoom to: 200mm if FF sensor, 133mm if Nikon DX, 125mm if Canon APS-C, 100mm if 4/3 or micro 4/3
(on a bridge camera, the lens is marked in equivalent focal lengths, so set 200mm)
d) focus on something with fine detail at a distance of say 15m, 15 yards or 45 feet away
e) repeatedly pan off, then re-taget the item and judge how much you're waving around when trying to be steady
f) now add your 500g weight, loop bag handles over the far end of lens
g) repeat step e) with the weight
h) was e) or g) better for stability?
i) tell us here, I could attach a poll (if Peter doesn't mind)

For bonus points, do it 10 times each way and actually take the shots, then compare on a computer to see which gave less camera shake.

Why?
b) so everyone is equal and we remove IS performance from the equation
c) so we are all looking at the same angle of view - figures arrived at by 200mm/crop factor (1.5, 1.6 and 2)

Any takers?

[MrB]

Has anyone else thought about the effect of the physical length of the lens at different focal lengths?

Presumably any slight rotational movements (in directions similar to the pitch and yaw of an aircraft) will have a greater blurring effect on the image when the length of the lens (i.e. from the front element to the sensor) is longer?

Philip

[knifebox]

I think it should be 1/ focal length X crop factor @ ISO 100

the posted fl on the lens is still its 35mm equivalent

[Peter Ryan]

Good idea Dave. Let's see how we go at the 'butter box' challenge. It is too late for me to do it tonight I will have a go tomorrow.

[Dave Humphries]

I think it should be 1/ focal length X crop factor @ ISO 100

Yes James you are correct (except iso isn't relevant), but to save getting complicated in later discussion, Peter sort of acknowledged that in his first paragraph where he says something like notwithstanding differences in sensor size.

It does no harm to mention it though, thanks,

[Dave Humphries]

Poll added for anyone doing the experiment

I suppose I'm gonna have to do it now, me and my big mouth!

[nickjohnson]

Peter,
I'm not sure that I fully understand why a zoom lens would be any different to a fixed lens of whatever focal length you have set on the zoom. That said (because I'm now likely to contradict myself !) - some thoughts.
The 1/focal length convention is as good a place to start as any since in reality, real world results fluctuate wildly.
As already mentioned, to be very confident of sharp results we may need 3 to 5 times faster shutter speed than given by our simple rule. On the other hand some of us are able to get good results at way slower speeds than the rule implies. I know one gent who regularly hand holds an 800mm at 1/60th, and gets commercial quality results! How can this be?
First – In the big space between silly slow and super fast, camera blur is a random event. Take a sequence of (say) five shots at lower than the “correct” speed and your likely to find that some are sharper (or less blurry) than others. With luck one or more will be properly sharp. I'm not advocating machine gun tactics as an alternative to good technique. Rather, I'm pointing out that digital capture gives us all the freedom to exploit the randomness – where appropriate.
Second – The physical support base may be critical – depending upon the individual. By this I mean the distance between your hands – with the camera in the shooting position. With a small lens the distance between your hands (one on the camera – the other on the lens) is small. So things are a bit wobbly compared to say a 300mm prime – where the lens hand can be away from the face and the elbow is not fully bent.
Third – Subject and circumstances. If your panning a moving subject – especially with a long lens – the inertia of the panning movement may make shots “possible” at a lower speed than you can manage with a purely static subject. If your using a zoom lens – with a zoom control that is toward the rear of the lens, and you are zooming whilst taking a sequence of images – expect results at slow speeds to be poor. Reasons – your support base is short and zooming makes that base unstable. In contrast – with the same lens, use a fixed zoom setting, and autofocus, and get a hold of the lens hood – better results ?
IS – The problem with Image Stabilisation (or VR or whatever) is the marketing. Talk of being able to make sharp images at x lower shutter speed is – at best – unhelpful and misleading IMHO. What IS does in practice is to load the randomness dice in your favour. So going back to our five shot sequence – we are likely to find that more of our images will be acceptable with IS than without.
HTH

Regards,

Nick.

[rpcrowe]

No one has mentioned the difference between sighting with an eye level viewfinder (three point hold with two hands and camera secured against the photographers eye - along with elbows tucked into the torso) and using the LCD viewfinder with the camera being held out in limbo only with two hands and away from the face...

I can see the obvious difference in my hold when shooting at slow speeds and using the above two different methods of viewing and holding the camera. I can personally hold a camera A LOT STEADIER viewing with the camera pressed against my eye than I can otherwise. However, since we all have different physical attributes, this may not be true for all photographers.

I suggest that some advocates of LCD viewing experiment with the stability of their holds when using the lCD viewer and when viewing with an eye level viewer.

[MrB]

I think it should be 1/ focal length X crop factor @ ISO 100
the posted fl on the lens is still its 35mm equivalent

Although I wouldn't disagree with the suggested formula, James, I was under the impression that the focal length printed on every lens was its actual focal length, not its 35mm equivalent?

Philip

[Dizzy]

After shooting high power target rifles for many years, I've learned how to breath and
steady myself for a shot. That was many years back, and although today I'm not as stable
as I once was (who is?..LOL), I can still use the same techniques and do quite well for
exposures up to 1/8s, or even 1/4s if I'm having a good day.

You've pointed out in your poll the secret to the stability, and that is the balanced
weight of the camera + lens. My last rifle was nearly 10 lb., and that weight is far more
stable than a lightweight carbine. I've found the same with the camera, as the 18mm-105mm
(with VR active) is much harder to hold steady for longer exposures (slower than 1/30s)
than the 70mm-300mm with it's VR active. Balanced weight is the key to being stable.

Found that the best position for me is the same I used for off-hand shooting; feet at shoulder
width (or more) and if you are right handed, pull your left elbow into the center of your chest
and tight to your body, then using the left hand cup the bottom of the body/lens at a balanced
point. Two controlled, deep breaths, inhale one more and let it half way out...hold .. and squeeze
the shutter.

Better yet, set your timer for a 5 sec. delay, squeeze the shutter after the second breath is exhaled,
and then you'll be in the most stable position when the shutter fires.

I'm sure there is some technical, mathematical algorithm that can be applied, but that is
somewhat meaningless IMO when the shutter speed limit we can manage as individuals
will vary due the multiple [human] factors involved. There may be some averages we can
go by, but if you practice your "breathing and squeezing" your skills are sure to improve.

YMMV, but that's what works for me.

Mike

[rpcrowe]

Philip stated, "I was under the impression that the focal length printed on every lens was its actual focal length, not its 35mm equivalent".

The raw focal length IS THE CORRECT focal length of any lens, despite the crop factor involved.

However, in judging the sharpness of any image, you must take into consideration how much that image needs to be enlarged to produce an acceptable product.

Obviously, an image from a crop camera needs to be enlarged to a greater degree than the image from a full-frame camera to get to any usable image size. Therefore the image produced in the crop format needs to be a bit sharper at the outset than the image from the full frame format and thusly needs a faster shutter speed to achieve that extra sharpness.

That is why we calculate the crop factor into the 1/FL x CROP FACTOR formula. In all seriousness, the formula is just a starting point to get you into the ballpark. There are far too many physiological, equipment and venue parameters to consider when determining the minimum shutter speed to have that formula be anything more than a rough starting point.

[Dave Humphries]

the posted fl on the lens is still its 35mm equivalent

I was under the impression that the focal length printed on every lens was its actual focal length, not its 35mm equivalent

The trouble is, lens labelling is inconsistent and the way we think about these things even moreso, especially when perhaps one person has FF and another has a crop factor body and this isn't apparent in one line.

A typical 4/3 (crop factor 2) kit lens is "14-42mm", by using crop factor, the non 4/3 users amongst us can work out that is equivalent to the angle of view we'd see with on a full frame camera is 28-84mm.

A typical APS-C kit lens is say, "18-55mm", by using crop factor we know to expect around 28mm to 80mm in terms of angle of view.

A Canon EF or Nikon FX lens sold as say "28-135mm" is just that, no factoring necessary, but if you put it on a crop body, you'll need to 'factor' the figures so you don't get a nasty surprise.

Most compact and bridge cameras are sold as '28-300mm', but these are already 'factored' figures. However, if you look deep in the specs, or on the front of the lens, it'll usually gives the lens' true focal length; e.g. "6.2-66mm".

So, apart from bridge cameras, the focal lengths stated are the true lens focal lengths, which is independent from the effect the sensor size has on the angle of view. The focal length doesn't actually change of course, only the angle of view, we just think in mm because it is easier than degrees with 2 decimal places.

Cheers,