question
Jun 29, 2016 12:39:00 #
loony wrote:
I have heard that your shutter speed should be no slower then your focal length. Example if you using a 400mm lens your shutter speed should be 1/400 are faster. the question is, if you have a lens that is 400mm on a 1.6 crop camera should your slowest shutter speed be 1/400 or 1/640?
That depends on the person, the camera format, whether the lens or body or both have image stabilization, plus how much practice, training, and caffeine you've had, what illnesses that produce tremors you might have, and many other variables.
It's a STARTING POINT rule of thumb, based on full frame (24x36mm) film or digital sensors. Multiply the focal length by the crop factor for other formats (1.5 for DX, 1.6 for Canon APS-C, 2X for m43, etc.).
Jun 29, 2016 12:41:23 #
chapjohn wrote:
There a couple of points to make. Using guidelines made for film are not always useful with digital. Discover what works.
As for the crop sensor, the "crop" has nothing to do with focal length, rather it refers to the field of view. Extention tubes change your focal length.
As for the crop sensor, the "crop" has nothing to do with focal length, rather it refers to the field of view. Extention tubes change your focal length.
Well written, well thought out......food for thought for sure.
Jun 29, 2016 12:42:23 #
amfoto1
Loc: San Jose, Calif. USA
Answer.
You know, with a more informative headline on your posts you might get more and better answers.
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But, seriously, with a crop sensor camera you are correct... you have to factor in the "behavior" of the lens.
The 1/focal length rule of thumb is based upon 35mm film/full frame cameras specifically. A crop camera magnifies things... including camera shake. So, yes, with a 1.6X (Canon) APS-C, you should multiply the lens focal length that way to estimate what shutter speed you need. With a 400mm lens, this guideline suggests a 1/640 shutter speed would be needed by most people, to have a reasonably good chance of getting sharp, hand-held shots.
Now, as some others have correctly suggested, the lens focal length actually doesn't change with different sensor (or film) formats. A 50mm lens is still a 50mm lens, regardless whether it's on a so-called "full frame" camera or on an APS-C... or for that matter an even smaller "Four/Thirds", or even larger medium format... or anything else.
What changes is the way that 50mm "behaves".
On a full frame camera, 50mm is a standard lens. On APS-C, it's a short telephoto. On medium format it's a wide angle. Heck, on some of the point-n-shoot digitals with tiny little sensors 50mm is a very powerful telephoto. Or, on a large format film camera, it would be an extremely wide lens. What changes are "angle of view" (aka field of view) and subject magnification.
Although it's still 50mm in all those cases, it behaves differently and this includes susceptibility to camera shake blur.
People's ability to hold things steady vary, both naturally and with practice and good techniques they've learned to use. So, this is always just a rule of thumb, what shutter speed you can or should use. With a steady hand and 30+ years experience, I know I can get a pretty high percentage of sharp, steady shots using shutter speeds a little slower than the rule suggest. You might be different... able to use even slower or needing to use faster. You'll just have to try it yourself.
Another consideration is image stabilization. Most modern cameras or their lenses have this feature (called different things, depending upon the manufacturer: IS, VR, OS, OSS, VC, etc.). With stabilization, most people see two or three or even four stops worth of assistance. Two stops of assistance with a 400mm lens would mean being able to relatively reliably hand-hold it at 1/100 shutter speed. Four stops would be 1/25.
I've been shooting with various Canon IS lenses for fifteen years and love it... especially on telephotos that are harder to hand-hold steady. Canon makes a superb 400mm f5.6L... very sharp and fast focusing... but lacking IS. I instead use a Canon 300/4L with IS... sometimes with a 1.4X teleconverter that makes it an effective 420mm f5.6... still with helpful image stabilization. However, you have to keep in mind that image stabilization, great as it is, can only help with camera shake. It can't do anything about subject movement blur. You still need to use faster shutter speeds to freeze moving subjects.
And, there are some exceptions. For example, high magnification shots such as are done with a macro lens are considerably more susceptible to camera shake, so a faster shutter speed is likely to be needed.
A flash also can be used to freeze movement... both camera shake and subject movement. Typical portable flash units at full power fire a very short duration of bright light... equivalent to approx. 1/720 shutter speed. (Fill flash, where ambient light is also part of the exposure, is another matter... it generally does not freeze motion of any type, or does so only partially resulting in a "ghosting" effect.)
And, of course, there are tripods and monopods that can be used to help steady a shot at slower shutter speeds. (However, in any SLR at shutter speeds between roughly 1/30 and 2 seconds you also have to think about internal vibrations from "mirror slap", which also can cause shake blur in images... Many cameras have a means of locking the mirror up to prevent this... Or Live View shooting might accomplish the same.)
No, they don't. Extension tubes only change a lens' close focusing ability, thereby making possible higher magnification, but at the cost of no longer being able to focus all the way to infinity. There is no change in it's effective focal length, when you add extension tubes behind a lens.
Teleconverters change a lens' effective focal length. (Yes, Canon calls their teleconverters "Extenders"... which might be a little confusing.) Teleconverters do not change a lens' closest focusing ability. That remains the same. However, a TC does magnify the subject and so can give similar end result as extension tubes.
Using either extension tubes or teleconverters change magnification, which in turn can require faster shutter speeds to help insure a sharp shot without camera shake blur.
You know, with a more informative headline on your posts you might get more and better answers.
******************
But, seriously, with a crop sensor camera you are correct... you have to factor in the "behavior" of the lens.
The 1/focal length rule of thumb is based upon 35mm film/full frame cameras specifically. A crop camera magnifies things... including camera shake. So, yes, with a 1.6X (Canon) APS-C, you should multiply the lens focal length that way to estimate what shutter speed you need. With a 400mm lens, this guideline suggests a 1/640 shutter speed would be needed by most people, to have a reasonably good chance of getting sharp, hand-held shots.
Now, as some others have correctly suggested, the lens focal length actually doesn't change with different sensor (or film) formats. A 50mm lens is still a 50mm lens, regardless whether it's on a so-called "full frame" camera or on an APS-C... or for that matter an even smaller "Four/Thirds", or even larger medium format... or anything else.
What changes is the way that 50mm "behaves".
On a full frame camera, 50mm is a standard lens. On APS-C, it's a short telephoto. On medium format it's a wide angle. Heck, on some of the point-n-shoot digitals with tiny little sensors 50mm is a very powerful telephoto. Or, on a large format film camera, it would be an extremely wide lens. What changes are "angle of view" (aka field of view) and subject magnification.
Although it's still 50mm in all those cases, it behaves differently and this includes susceptibility to camera shake blur.
People's ability to hold things steady vary, both naturally and with practice and good techniques they've learned to use. So, this is always just a rule of thumb, what shutter speed you can or should use. With a steady hand and 30+ years experience, I know I can get a pretty high percentage of sharp, steady shots using shutter speeds a little slower than the rule suggest. You might be different... able to use even slower or needing to use faster. You'll just have to try it yourself.
Another consideration is image stabilization. Most modern cameras or their lenses have this feature (called different things, depending upon the manufacturer: IS, VR, OS, OSS, VC, etc.). With stabilization, most people see two or three or even four stops worth of assistance. Two stops of assistance with a 400mm lens would mean being able to relatively reliably hand-hold it at 1/100 shutter speed. Four stops would be 1/25.
I've been shooting with various Canon IS lenses for fifteen years and love it... especially on telephotos that are harder to hand-hold steady. Canon makes a superb 400mm f5.6L... very sharp and fast focusing... but lacking IS. I instead use a Canon 300/4L with IS... sometimes with a 1.4X teleconverter that makes it an effective 420mm f5.6... still with helpful image stabilization. However, you have to keep in mind that image stabilization, great as it is, can only help with camera shake. It can't do anything about subject movement blur. You still need to use faster shutter speeds to freeze moving subjects.
And, there are some exceptions. For example, high magnification shots such as are done with a macro lens are considerably more susceptible to camera shake, so a faster shutter speed is likely to be needed.
A flash also can be used to freeze movement... both camera shake and subject movement. Typical portable flash units at full power fire a very short duration of bright light... equivalent to approx. 1/720 shutter speed. (Fill flash, where ambient light is also part of the exposure, is another matter... it generally does not freeze motion of any type, or does so only partially resulting in a "ghosting" effect.)
And, of course, there are tripods and monopods that can be used to help steady a shot at slower shutter speeds. (However, in any SLR at shutter speeds between roughly 1/30 and 2 seconds you also have to think about internal vibrations from "mirror slap", which also can cause shake blur in images... Many cameras have a means of locking the mirror up to prevent this... Or Live View shooting might accomplish the same.)
chapjohn wrote:
...Extention tubes change your focal length.
No, they don't. Extension tubes only change a lens' close focusing ability, thereby making possible higher magnification, but at the cost of no longer being able to focus all the way to infinity. There is no change in it's effective focal length, when you add extension tubes behind a lens.
Teleconverters change a lens' effective focal length. (Yes, Canon calls their teleconverters "Extenders"... which might be a little confusing.) Teleconverters do not change a lens' closest focusing ability. That remains the same. However, a TC does magnify the subject and so can give similar end result as extension tubes.
Using either extension tubes or teleconverters change magnification, which in turn can require faster shutter speeds to help insure a sharp shot without camera shake blur.
Jun 29, 2016 12:55:53 #
loony wrote:
I have heard that your shutter speed should be no slower then your focal length. Example if you using a 400mm lens your shutter speed should be 1/400 are faster. the question is, if you have a lens that is 400mm on a 1.6 crop camera should your slowest shutter speed be 1/400 or 1/640?
That was the 'rule-of-thumb' before IS, VR, OS, etc. Another variable is the photographer. The answer to your question is 1/640 unless you have IS ... etc. Just have fun after you determine how steady your hands and arms are and what is your minimum shutter speed with that lens. Best, J. Goffe
Jun 29, 2016 14:17:03 #
loony wrote:
I have heard that your shutter speed should be no slower then your focal length. Example if you using a 400mm lens your shutter speed should be 1/400 are faster. the question is, if you have a lens that is 400mm on a 1.6 crop camera should your slowest shutter speed be 1/400 or 1/640?
That rule was from before image stabilization. You can go much slower with a lens with good image stabilization. But you will generally get sharper images handheld if you follow the simple rule.
Jun 29, 2016 14:48:35 #
jackpi
Loc: Southwest Ohio
loony wrote:
I have heard that your shutter speed should be no slower then your focal length. Example if you using a 400mm lens your shutter speed should be 1/400 are faster. the question is, if you have a lens that is 400mm on a 1.6 crop camera should your slowest shutter speed be 1/400 or 1/640?
Shutter speed depends on your ability to hold the camera steady, lens stabilization effectiveness, and subject motion. If the subject isn't moving and your lens isn't stabilized and you have no difficulty hand-holding, 1/(focal x crop factor) should work.
Jun 29, 2016 14:53:39 #
If a lens on a crop sensor camera does not magnify the image, but simply projects less of the scene onto a smaller sensor, it should not have an effect on hand hold ability. If it does, than shooting with a full frame camera with the intention of cropping the final image, you would have to factor in the same crop factor.
Just thinking out loud.
And while I could be wrong, reading something in a magazine doesn't make it right either.
--
Just thinking out loud.
And while I could be wrong, reading something in a magazine doesn't make it right either.
--
Jun 29, 2016 17:02:35 #
amfoto1 wrote:
What changes is the way that 50mm "behaves&qu... (show quote)
The lens behavior is exactly the same regardless of the sensor size. It projects the exact same size image focused at the exact same distance. The only change is not the lens but the sensor, which uses less of the projected image with an APS-C sensor than with a full fame sensor.
amfoto1 wrote:
No, they don't. Extension tubes only change a lens' close focusing ability, thereby making possible higher magnification, but at the cost of no longer being able to focus all the way to infinity. There is no change in it's effective focal length, when you add extension tubes behind a lens.
Actually extension tubes do change the effective focal length. Calculate the focal length needed for a specific magnification, such as1:1, at the given focus distance and it will not come out to the marked focal length for focus at infinity. Or calculate the effective fstop with extension tubes and that also shows the very same change in focal length too because the diaphragm diameter opening didn't change so the fstop change has to be caused by an effective focal length change.
amfoto1 wrote:
Teleconverters change a lens' effective focal length. (Yes, Canon calls their teleconverters "Extenders"... which might be a little confusing.) Teleconverters do not change a lens' closest focusing ability. That remains the same. However, a TC does magnify the subject and so can give similar end result as extension tubes.
Teleconverters change the actual physical focal length for infinity focus, using a Barlow lens.
Jun 29, 2016 17:09:17 #
Bill_de wrote:
If a lens on a crop sensor camera does not magnify the image, but simply projects less of the scene onto a smaller sensor, it should not have an effect on hand hold ability. If it does, than shooting with a full frame camera with the intention of cropping the final image, you would have to factor in the same crop factor.
It does, and you are correct about the effect being exactly the same when using a full frame sensor and cropping later with an editor. There is no free lunch, just a question of where in the workflow the cash register is located. The price is the same...
Jun 29, 2016 18:47:35 #
camerapapi wrote:
No matter what camera is in use, the shutter speed when the camera is hand held, unless camera or lens have IS, should be minimum 1/focal length but if higher then better.
The reasoning comes from an era when IS was not in use.
A lens or camera with IS can do very well hand held at slower speeds than 1/focal length to a certain degree. If using a long lens I still prefer a tripod whenever possible for stability.
The reasoning comes from an era when IS was not in use.
A lens or camera with IS can do very well hand held at slower speeds than 1/focal length to a certain degree. If using a long lens I still prefer a tripod whenever possible for stability.
The real answer is. . .
Try it. Some people can handhold without IS at slower speeds, most of us can barely do it at 1/fl and a few have trouble even at greater speed.
Try it with IS. That could be worth 3,4,5 stops--or not.
Rules of thumb depend on how steady the thumb is.
Jun 29, 2016 19:16:47 #
Reinaldokool wrote:
The real answer is. . .
Try it. Some people can handhold without IS at slower speeds, most of us can barely do it at 1/fl and a few have trouble even at greater speed.
Try it. Some people can handhold without IS at slower speeds, most of us can barely do it at 1/fl and a few have trouble even at greater speed.
How did you come to that conclusion?
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Jun 29, 2016 22:11:41 #
Jun 29, 2016 22:59:29 #
Keep in mind the 1/focal length shutter speed assumes a good handholding technique, "normal" subject distances, a "normal" magnification for printing, and a static subject.
Jun 30, 2016 01:27:50 #
loony wrote:
I have heard that your shutter speed should be no slower then your focal length. Example if you using a 400mm lens your shutter speed should be 1/400 are faster. the question is, if you have a lens that is 400mm on a 1.6 crop camera should your slowest shutter speed be 1/400 or 1/640?
1/640
Jun 30, 2016 07:13:10 #
Thank you for all the feed back. I guess I am going to have to experiment and find out what works best.
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