shutter speed vs focal length

[XitzpatX]

I know that in 35mm terms there's a little rule that when shooting hand held you shouldnt have your shutter speed slower than that of your lenses focal length (like if youre using a 50mm lens you cant have it slower than 1\50th). Now since medium format lenses tend to be on the longer side like an 80mm lens but have a field of view like a 50mm should I shoot if faster than the original focal length or shoot it faster than the focal length with reverse crop factor. Im asking this because im going to go to my friends bands gig and I want to know if I can get that extra stop of light without creating unwanted motion blur. -Thanks

 

[tirediron]

A LOT depends on the camera itself. Some, like the Mamiya 645 are easy to hand hold, others, like the Pentax 67 not so much. I generally try and go for at least FL+50% for MF shooting.

 

[compur]

Effects of camera-shake on a hand-held 80mm lens (or any focal length) is the same regardless of film format -- 110, 35mm, 6x6, 4x5, etc., etc.

But, of course, other factors can come into play indirectly with different formats such as camera weight, ergonomics, etc. For example, I would find it easier to hold steady a Pentax 67 than a Pentax Auto 110 just because of weight.

 

[Derrel]

Well...motion blur depends not simply on some arbitrary shutter speed, but on how large the image is (the degree of magnification); what speed the motion actually is; and what direction the motion is occurring in in relation to the lens axis.

For example, if motion is far,far away, it can be stopped with a slowish shutter speed. Cars on a bridge 3/4 mile distant will be rendered very,very tiny; low magnification, so a slowish speed will effectively stop the motion. Even though the cars might be crossing the bridge at 55 MPH, if the camera is 3/4 mile away, the cars will appear for all intents, "frozen" at 1/50 second with an 80mm. IF however, the camera is 15 feet from the interstate, the cars will NOT be stopped with the same slow speed that was adequate at 3/4 mile distance. You might very well need 1/2000 second.

Motion in relation to the lens axis: movement "across" the field of view needs a briefer (faster speed) exposure than if the motion is coming directly AT or AWAY FROM the camera position. Angled motion, somewhere in between.

Speed of the motion...the hands and feet of a runner, or the drum sticks, are moving the fastest in a shot of a man running, or playing the drums; the shoulders will be effectively stopped at say, 1/125 second--but the hands or drumsticks might very well need a speed 4 to 5x faster...again, "depending". When a drumstick hits the skin..the hand and might be stopped for a brief time...a guitarist's strumming the strings will have his hand stop, briefly, at very frequent, brief intervals.

Basically...from 15-20 feet away with an 80mm, you're going to probably need to shoot for "timing". I have no idea how you're shooting, but mirror slap/crowd jostling you/shutter vibration and motion blur are probablyh both going to co-exist in some measure at the slower end of the speed spectrum. I'd shoot ISO 400 film.

 

[Mike_E]

^^^ That.

That being said, a monopod or tripod will greatly enhance MF. You're not in it just for the size, right?

 

[timor]

I would find it easier to hold steady a Pentax 67 than a Pentax Auto 110 just because of weight.

That maybe not the best example, Pentax 67 has a horrendous mirror slap dangerous even when camera is mounted on the tripod, but in general yes, heavier are easier to hold steady.

 

[cgw]

I know that in 35mm terms there's a little rule that when shooting hand held you shouldnt have your shutter speed slower than that of your lenses focal length (like if youre using a 50mm lens you cant have it slower than 1\50th). Now since medium format lenses tend to be on the longer side like an 80mm lens but have a field of view like a 50mm should I shoot if faster than the original focal length or shoot it faster than the focal length with reverse crop factor. Im asking this because im going to go to my friends bands gig and I want to know if I can get that extra stop of light without creating unwanted motion blur. -Thanks

What camera are you shooting? Leaf or focal plane shutter?

 

[cgw]

I would find it easier to hold steady a Pentax 67 than a Pentax Auto 110 just because of weight.

That maybe not the best example, Pentax 67 has a horrendous mirror slap dangerous even when camera is mounted on the tripod, but in general yes, heavier are easier to hold steady.

You've shot Pentax 67 extensively? I'd guess not, judging from this comment.

 

[XitzpatX]

What camera are you shooting? Leaf or focal plane shutter?

Im shooting with a mamiya 7 and I believe that has a leaf shutter

 

[timor]

I would find it easier to hold steady a Pentax 67 than a Pentax Auto 110 just because of weight.

That maybe not the best example, Pentax 67 has a horrendous mirror slap dangerous even when camera is mounted on the tripod, but in general yes, heavier are easier to hold steady.

You've shot Pentax 67 extensively? I'd guess not, judging from this comment.

Long enough but I switched to Koniomega in this format. Now I don't experience things like shutter bounce.

 

[cgw]

That maybe not the best example, Pentax 67 has a horrendous mirror slap dangerous even when camera is mounted on the tripod, but in general yes, heavier are easier to hold steady.

You've shot Pentax 67 extensively? I'd guess not, judging from this comment.

Long enough but I switched to Koniomega in this format. Now I don't experience things like shutter bounce.

OK, so what is it? Mirror slap or shutter bounce? Most of the mirror slap sound/vibration was post-exposure anyway--something the "urban legend" about the P67's shortcomings missed. Later models had MLU. Still puzzled by your idea that tripod mounting has anything to do with mirror slap.

 

[timor]

Still puzzled by your idea that tripod mounting has anything to do with mirror slap.

I know you mix ideas sometimes. This thread is about abilities and limitations in hand shooting a camera. Read all.

 

[cgw]

What camera are you shooting? Leaf or focal plane shutter?

Im shooting with a mamiya 7 and I believe that has a leaf shutter

Your concern about motion blur/camera shake obviously depend on shutter speed which will depend on available light and aperture along with film speed. Really need more specifics to help.

 

[cgw]

Still puzzled by your idea that tripod mounting has anything to do with mirror slap.

I know you mix ideas sometimes. This thread is about abilities and limitations in hand shooting a camera. Read all.

Just reading what you posted. Seems you're talking thru your hat about the P67. No one needs that.

 

[XitzpatX]

Your concern about motion blur/camera shake obviously depend on shutter speed which will depend on available light and aperture along with film speed. Really need more specifics to help.

Its an indoor event so im probably gonna shoot some hp5+ and I might push it a stop or two, most likely im gonna shoot wide open at f/2.8 or f/4