Minimum hand held shutter speed calculation

[Chris Harvey]

I shoot with a Mamiya 645 super and was wondering how the 35mm SLR rule of thumb of 1/focal length of the lens for the minimum hand held shutter speed works with MF is it the same?

Thanks

Chris

 

[Christopher Walrath]

It would. Bigger camera, might double that just to be on the safe side. Unless you have not a worry in the world.

 

[RalphLambrecht]

I shoot with a Mamiya 645 super and was wondering how the 35mm SLR rule of thumb of 1/focal length of the lens for the minimum hand held shutter speed works with MF is it the same?

Thanks

Chris

We talked about this in a recent thread: It's not a 35mm rule, it's a MF rule. It's way too liberal for 35 mm!

 

[MattKing]

I had a flash of deja vu:

(there was a url link here which no longer exists)

It is a good question.

 

[MattKing]

Ralph:

Great minds think alike - on most things!

 

[RalphLambrecht]

Ralph:

Great minds think alike - on most things!

Matt

Full agreement would be boring!

 

[Chris Harvey]

Cheers folks thanks for your help

 

[2F/2F]

It is just a rule of thumb anyhow, so isn't universally accurate; only better than nothing for those who have not yet found out for themselves. I find hand holdable speeds to vary from camera to camera, and even from shot to shot with the same camera, depending on how it is being held. You need to try it yourself with each camera and see what you get.

I find that waist-level-viewing cameras give the best slow-shutter hand holdability. I find them better than eye-level-viewing cameras in this area because they are often cradled in the hands very solidly (and these hands are connected to arms which are also more solidly located against the body), and the camera is also often braced against your body as well.

 

[Ian Grant]

Looking back through pre WWII photo-books the minimum recommended hand held shutter speeds were the same regardless of format, with a standard lens. This is borne out in practice, it's no different using a 35mm camera hand held as as 5x4 Press camera, at speeds like a 1/25th(/30th), 1/50th(1/60th) etc, all increase in sharpness with shutter speed. A larger format doesn't make it easier, the lesser enlargement factor might mask it slightly but any slight wobble is amplified by the larger sized format so it evens out

It was the German 35mm camera systems that brought in the rule of thumb with regard to focal length & shutter speeds, the range-finder Leica's & Contax's, followed by the SLR Exacta's and Praktina's in the late 30's an it doesn't have it's roots in medium format at all, but can of course be applied there as well.

These 35mm cameras where the first mass market cameras that could take a wide variety of lenses and be hand-held. It was a few years before MF cameras began to catch up in terms of lens ranges etc, Hasselblad being the first.

The rule of thumb using a minimum shutter speed equal to focal length breaks down anyway as soon as you use wide angle lenses, you can't shoot hand held at a 1/15th easily with a 17mm WA. It's just a very loose quick and dirty guide for standard & more importantly telephoto lenses.


Ian

 

[RalphLambrecht]

... A larger format doesn't make it easier, the lesser enlargement factor might mask it slightly but any slight wobble is amplified by the larger sized format so it evens out ...

The larger the format, the larger the CoC, the less camera shake has an effect. Since we are talking about a focal-length depending rule-of-thumb, the larger format does not amplify camera shake. It's easier to hand-hold a 50mm MF lens than the same focal length on a 35mm camera.

 

[Ian Grant]

You're wrong Ralph. If you think of the amount of shake as a variation in degrees around an axis, either one or many, then format size is important. With a larger format a simple variation is greater the further from the axis. Camera shake is generally how a camera is balanced around a crude axis between two hands or a pivot one hand, and that's in 3 dimensions

Of course this is complicated by many smaller cameras often being easier to hold for ergonomic/design reasons

The fallacy is comparing formats with each other, it's about comparing hand held shots at various shutter speeds made with the same camera. Our expectations are far higher with larger formats so we can't compare it to 35mm.

Yes larger formats mean the " crude Rule of thumb" needs modifying as format size increases. but comparing standard lens the effects of shutter speed on loss of sharpness are remarkably close, in terms of loss of expected sharpness.

There's no hard & fast rules, with 35mm the balance of a camera changes very significantly when a longer lens is added, this is a major reason for the rule of thumb.

The bottom line is that with a standard lens or wider regardless of format (up to 5x4) 1/30th is generally accepted as being the minimum usable hand held speed, to get fairly consistent results, 1/60th gives a much higher percentage of reasonable s harp images and by a 1/125th there shouldn't be an issue.

Ian

 

[Thomas Bertilsson]

I have a Hasselblad camera, which is similar to your Mamiya in terms of shape, weight, etc. With an 80mm lens I can hand hold to about 1/60th s, and with the 150mm I can hand hold to about 1/125th s with reasonable sharpness. Longer shutter speeds than that and I generally have to accept some blur from whatever movements affect the camera.
That is what I have noticed with my particular medium format camera, and works pretty well for me to use as a rule of thumb.

With 35mm I can shoot a 55mm lens at about 1/30th s, and a 100mm lens at about 1/60th s, and get reasonably sharp pictures. About the same performance as the medium format camera, and based on that empirical evidence, the focal length of the lens definitely is a factor, regardless of format.

My findings may, of course, not be true for others.

- Thomas

I shoot with a Mamiya 645 super and was wondering how the 35mm SLR rule of thumb of 1/focal length of the lens for the minimum hand held shutter speed works with MF is it the same?

Thanks

Chris

 

[Ian Grant]

Those Hasselblads are notorious for their mirror slap

Well according to people that don't use them on the internet

I've used my Mamiya 645s quite regularly with a 45mm & 80mm lens at 1/30th hand held yes there's sometimes a bit less sharpness but not much, as Thomas says 1/60th is usually OK.

How much is the camera, or how we hold it, it's very individual. Often an MF SLR at a 1/30 or 1/60th is sharper hand-held than on a tripod unless the mirror lock is used when on a tripod, our bodies help damp the mirror bounce

Ian

 

[jeffreyg]

Be careful of rules of thumb. Some thumbs shake at rather fast shutter speeds. Personally I use a tripod unless it's impossible (medium format) and always with large format. When hand holding I use the fastest shutter speed possible with the aperture needed for depth of field. If it won't work I don't take it because it is not likely I would bother to print it. I don't look for reasonable sharpness - it's either sharp or purposely soft. IMHO

http://www.jeffreyglasser.com/

 

[RalphLambrecht]

You're wrong Ralph. ...

You sound like my wife now! Not a very diplomatic start.

... Yes larger formats mean the " crude Rule of thumb" needs modifying as format size increases. ...

Keep going, you're getting there.

... but comparing standard lens the effects of shutter speed on loss of sharpness are remarkably close, in terms of loss of expected sharpness. ...

Ouch, I see where you missed it. We are not comparing standard focal lengths; we are comparing identical focal lengths. The rule-of-thumb says:

min shutter speed = 1 / focal length

The effect is different for different film formats, because of their different CoCs.

... The bottom line is that with a standard lens or wider regardless of format (up to 5x4) 1/30th is generally accepted as being the minimum usable hand held speed, to get fairly consistent results, 1/60th gives a much higher percentage of reasonable s harp images and by a 1/125th there shouldn't be an issue.

Well, that's just proof that the rule-of-thumb does not apply to all film formats. What you need to do is change the rule-of-thumb to saying that equivalent focal lengths require the same min shutter speed. But, that's just another way of saying that film format matters, and that the above rule-of-thumb is only good for one film format, which is medium-format by the way.

 

[tkamiya]

What I keep wondering about this is that no matter what shutter speed and focal length of lens we use, if we move, there will be some blurring of the image. The question really is, is this blurring objectionable in the final product, which usually is the print. If this is true, what is acceptable depends on size of the print as well. One is likely to enlarge images from medium format film much more than 35mm. If this is true, it all depends on focal length of lens, size of film, and size of the print.

Would this "rule of thumb" thing really beneficial at all beyond it's just rule-of-thumb?

 

[RalphLambrecht]

What I keep wondering about this is that no matter what shutter speed and focal length of lens we use, if we move, there will be some blurring of the image. The question really is, is this blurring objectionable in the final product, which usually is the print. ...

As soon as the blurring is more than the CoC, it will be detectable for people with normal vision. Objectionable is a subjective term.

... If this is true, what is acceptable depends on size of the print as well. One is likely to enlarge images from medium format film much more than 35mm. If this is true, it all depends on focal length of lens, size of film, and size of the print. ...

What is acceptable does not depend on the size of print if one follows the idea of CoC, which is the basis of all depth of field markings. In order to keep depth-of-field scales independent of print size, lens and camera manufacturers make the reasonable assumption that for uncropped prints of 8x10 inches or larger, the normal viewing distance is approximately equal to the print diagonal. For an 8x10-print and the standard minimum visual angle of 1 minute of arc, this calculates to a minimum viewing distance of 325 mm and a resolving power of 10 lines/ mm or 5 lp/mm. In other words, at this distance and under normal viewing conditions, the human eye cannot separate print detail smaller than 0.2 mm.

Although I have used the 8x10print as an example, the assumption of a fixed relationship between viewing distance and print size is appropriate for all print sizes. Any change to the negative magnification is mathematically compensated for by a change in viewing distance. This conveniently keeps the size of the minimum negative detail, for all full-negative enlargements of a given negative format, consistent.

 

[AgX]

You're wrong Ralph. If you think of the amount of shake as a variation in degrees around an axis, either one or many, then format size is important. With a larger format a simple variation is greater the further from the axis.

I don't get yor point with the part underlined by me.
Any base tilt or central swing of the same angle will have the practically* same effect on any camera, non-withstanding format, as long as angle-of-view is the same.

*the larger the body in case of tilt at edge of body, the absolute dislocation of camera body will be greater in height and focus, but the optical effect will be dominated by the angular mnovement.

 

[Robert Budding]

I add in a correction factor for the number of cups of coffee that I've consumed that day:

shutter speed = (1/focal length) * (1/cups of coffee)

(I always have at least one cup)

 

[AgX]

You're wrong Ralph. If you think of the amount of shake as a variation in degrees around an axis, either one or many, then format size is important. With a larger format a simple variation is greater the further from the axis.

I don't get your point with the part underlined by me.

Any base tilt or central swing of camera body will have practically* the same effect with any format, as long as the angle of view is the same.

* With larger bodies tilt at edge of body will induce more absolute dislocation in height and focus, but that shall be overdone in optical effect by the angular movement of field of view anyway.

 

[Sirius Glass]

It is just a rule of thumb anyhow, so isn't universally accurate; only better than nothing for those who have not yet found out for themselves. I find hand holdable speeds to vary from camera to camera, and even from shot to shot with the same camera, depending on how it is being held.

For me, it depends on what is in the shots!


Steve

 

[Ian Grant]

With a larger format a simple variation is greater the further from the axis.

I don't get your point with the part underlined by me.

Think of photographing a moving propeller on a plane, the centre will look sharper than the edges.

Any base tilt or central swing of camera body will have practically* the same effect with any format, as long as the angle of view is the same.

* With larger bodies tilt at edge of body will induce more absolute dislocation in height and focus, but that shall be overdone in optical effect by the angular movement of field of view anyway.

The problem is that the rule of thumb is very unsound logic.

The way Ralph interprets it you should be able to hand hold a 55mm lens on a MF camera and get much sharper results than with a 55mm lens on a 35mm camera at the same speed but apart from the format factor that just isn't the case. Taking that logic further using a 17mm lens on a 35mm camera it should be very much easier to use hand held at slow speeds but in fact the opposite is true.

Too many other factors other than focal length are also important to image sharpness, wider angle lenses often mean detail is very much finer which is quickly lost with any camera shake. Then there's distance from the lens/camera, we've all taken or seen images made from cars. trains etc where objects nearer to the camera are quite blurred through movement while distant objects appear sharper. In more normal use that means that the closer the subject is to the camera the greater effect of any camera shake, which of course is at it's most critical with macro work.

So there's a point where "the rule of thumb" breaks down and other factors become more important. However with a standard focal length lens and longer as the angle of view narrows the "rule of thumb" becomes a rough and ready reminder that camera shake becomes more critical requiring higher shutter speeds with telephoto lenses


Ian

 

[RalphLambrecht]

... The way Ralph interprets it you should be able to hand hold a 55mm lens on a MF camera and get much sharper results than with a 55mm lens on a 35mm camera at the same speed but apart from the format factor that just isn't the case. ...

That is exactly what happens. You cannot arbitrarily ignore the format factor. You need to consider the entire image making process, including CoC.

... Taking that logic further using a 17mm lens on a 35mm camera it should be very much easier to use hand held at slow speeds but in fact the opposite is true. ...

No, no, that's true too. That's what the 1/focal length rule is all about.

... So there's a point where "the rule of thumb" breaks down and other factors become more important. However with a standard focal length lens and longer as the angle of view narrows the "rule of thumb" becomes a rough and ready reminder that camera shake becomes more critical requiring higher shutter speeds with telephoto lenses.

That may be; the rule-of-thumb is just that, a rule-of-thumb. But the point was, camera format matters. The rule as stated works best for MF. For 35mm it's too liberal and for LF it is a bit conservative. Every 4x5 shooter will tell you that shutter speeds slower than 1/125 s are quite possible.

 

[Removed Account2]

Bigger camera = bigger mass = more latitude.

It is easier, up to a point, holding a heavy camera still than a flimsy plastic thingie.

I have no big problem holding my 120 TLR's still at 1/(focuslengthx2), most of the time.

The annoying bit is that every time it fails, it is *important* pictures!

 

[RalphLambrecht]

... The annoying bit is that every time it fails, it is *important* pictures!

That's what they all say: The ones I missed were the best ones!