Shutter speed v focal length question

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Bazza
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Yes I know the shutter speed should be the same of faster than the lens focal length. The question I would like an answer to is, I have a Nikon AFS 80-400mm f4.5-6.6 G ED lens and when married to a crop sensor (Nikon D300 ) it produces not 400 mm at the longest,but with the x 1.5 crop it becomes a 600mm lens. Therefore what should the ideal minimum shutter speed be ? 1/400sec or 1/600sec

Thanks for all and any answers in advance
 
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The 'rule' goes you need to factor in the crop factor into the calculation so 1/600.
 
Yup, the "focal length" should be in 35mm/FF equivalent so 1.5x the actual focal length used. In the real world, some will be able to hand hold at far lower than 1/EFL(35mm) and others will struggle at far faster shutter speeds. Of course, VR/OS/IS/VC will help reduce camera shake but will do nothing for subject movement. Best bet is to see how low you can go with each lens at assorted focal lengths - an 18mm prime on a Fuji (27mm EFL) is far easier to HH at 1/30th than an 18-135, although the zoom has stabilisation so...

These days, I'm in the 1/2xEFL band for hand holding!
 
Nod Thanks for your reply and Sharky


Nod I did ask specifically about the 80-400mm lens and camera no other lens. but thanks again for your information

Sharky thanks that is what I really wanted to know

Oh and i have just chucked out my sigma 1.5 tele converter, it had works loose between the front and back making it impossible to use. Took it to bits as far as possible and looked to me like a poor build originally. I had it for years as a replacement for another sub standard one. So Sigma TC's are a no no for me now
 
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And if you crop the image further in post processing, that affects the ratio too.
 
As does the megapixel rating. As MPs increase, so does the minimum hand-holdable shutter speed, so your 1/600th may be ok on your D300, but should you upgrade to the D7200 for example, you may find this becomes 1/900th.
 
The 1/focal length for shutter speed is only a guide (including any crop factor effect on the lens), but a good place to start when setting up your camera for shutter priority. As you get more confident, your shutter speeds will come down especially as the 80-400mm a reasonably light lens
 
I used to hand hold my 500 f4 down to 125th and the 300 f2.8 at 60th - it just takes practise and the subject in question. If the subject is moving and you follow focus, the subject stays sharp, like WSB with the bikes crossing the frame diagonally (inside of a big sweeping bend, such as Coppice at Donnington) with the rider looking straight down the barrel of the lens. Yes, there were plenty of throw aways, but you aren't after them, you are after the one that works!
 
As does the megapixel rating. As MPs increase, so does the minimum hand-holdable shutter speed, so your 1/600th may be ok on your D300, but should you upgrade to the D7200 for example, you may find this becomes 1/900th.

My other camera is a Nikon D800
 
The 1/focal length for shutter speed is only a guide (including any crop factor effect on the lens), but a good place to start when setting up your camera for shutter priority. As you get more confident, your shutter speeds will come down especially as the 80-400mm a reasonably light lens


I have been taking photos for over 50 years on and off. I prefer to use aperture settings or manual . Managed some time ago to win a couple of international photo competitions so not a complete novice. I don't have any problem with keeping the camera steady with that lens, it has a very good VR on it.

It comes in at a weight 1,570 g (3.5 lb.) so not exactly what I would call light

Nikon D300 lens AFS 80-400mm taken at 600mm at a distance of 75 ft as a try out with that camera hand held
D300 is not a FF camera




Nikon D800 with an AFS 50mm f1.4 G lens as a comparison



No editing straight from camera exif available and can be checked
 
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I've always found his rule interesting and not so much to do with he crop factor but more to do with the pixel density and I suppose final viewing size.

Because, a 400mm lens is a 400 on full frame and it is a 400 on a crop. The only difference is on the crop you are seeing less of the edges. With the same pixel density if something in he middle of the image moves by one degree which causes blur across 5 pixels it will affect both sensors identically.

The true factor has to be megapixel density, so it is getting harder to get sharp images but when you do they are sharper than they could ever have been, also is has improved.

So yes, you should test your equipment and your own ability but the 1.6 crop factor is not alone magnifying the image and any blur compared to full frame, it is just removing the edges.

A 5ds full frame 50mp would be harder to handhold than a 6mp 30d 1.6x crop...
 
And if you crop the image further in post processing, that affects the ratio too.

As does the megapixel rating. As MPs increase, so does the minimum hand-holdable shutter speed, so your 1/600th may be ok on your D300, but should you upgrade to the D7200 for example, you may find this becomes 1/900th.

These are essentially saying the same thing, MP don't make a difference if you are viewing at normal sizes, it's only when you zoom in (or crop, to use Richards version) that MP matter.

It's all about magnification - the more you magnify the faster the shutter speed required as you are also magnifying the shake (just ask macro photographers - 1/FL doesn't really work), whether you magnify by using a smaller sensor, zooming in on screen or printing big, it is all magnification.
 
same shot same distance but with D800 and same 80-400mm lens (bit misty today) all at the 400mm length, hand held


ISO 100 F6.3 1/400 SEC
D300 12 mP against D800 36 mp
 
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Some posters are getting things mixed up. Two halves of the same coin maybe, but not the same.

The shutter speed = focal length thing is not a rule, but a rule of thumb, a rough guide*. Images do not magically become sharp as soon as you achieve the prescribed ratio, they merely become 'acceptably sharp'. There is always some camera shake with a hand-held picture, but it gets progressively reduced with faster shutter speeds until it's 'acceptable'. What is 'acceptable'? Well, your guess is as good as mine but this rule of thumb goes back a long way, to when a 10x8in print from 35mm film was a good size enlargement. Today's standards are higher, and this is where pixel count comes in - the closer you look, the more critical you are and the higher your required standard of sharpness, the higher the shutter speed needs to be.

But the rule of thumb as we commonly use it is unrelated to pixels - it's simply about magnification. And in that sense, it holds good, regardless. Say you get a good sharp image at 1/100sec with a 100mm lens, then with a 200mm lens you'll need 1/200sec to counterbalance the increased magnification of the longer focal length, a 400mm lens needs 1/400sec and so on. Not everyone can hand-hold to the same standard, and what do you call acceptably sharp? Everyone should do their own tests, and output the images to their usual standard, and draw up their own set of guide lines.

If you do that, and shoot a sequence of pictures around your personal limit, you will not see them all equally blurred. Some will be sharp, some will be acceptable, some not. The point here is, when you're up against it and fighting to get a sharp result, there is safety in numbers. Shoot a sequence with the camera in continuous drive mode, and there's a very good chance at least one will be good. Your chances of success are dramatically increased.

*The fact that the shutter speed = focal length rule of thumb works directly with full-frame (35mm film) cameras is pure coincidence. For all other formats, a conversion factor, eg crop-factor, must be applied.
 
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