Shutter speed and f/stop ratio..

[lennon33x]

Doesn't it always?

Blam!

 

[Braineack]

no, why would you?

Because some theories suggest 1/(crop factor x focal length). Therefore Derrel's suggestion trumps.

50mm lens = 1/80 shutter speed

But then on an FX, you're at 1/50 when you'd probably wanna be at 1/100.

 

[Gavjenks]

But then on an FX, you're at 1/50.

1 / ([amount the final image will be cropped versus a full frame] x [focal length] x 2)

 

[Braineack]

But then on an FX, you're at 1/50.

1 / ([amount the final image will be cropped versus a full frame] x [focal length] x 2)

how in the world are you supposed to know that? Seems to me that if you capture something as sharp as it's going to be captured, that decreasing the shutter speed further is not going to matter, no matter how much you crop.

if anything it should be: 1 / ( [focal length] x [2 + ([MP - 16] / 10) ] )*

Where a 36MP camera would be 1 / FL x 4
and a 24MP camera would be 1 / FL x 2.8

The formula is for trying to pick the shutter speed that will result in a tact sharp capture, beyond that crop at will, right?


*I realize my formula is completely flawed.

 

[Overread17 5]

As said the rule of thumb was devised on 35mm sensor/film cameras so any change to that factor will affect things. It's not a straight conversion though. A larger sensor/film would suggest a slower minimum shutter speed; however many of those cameras also have a much increased weight which fast increased fatigue which then flips in an increase.

For crop sensor cameras a multiplication of 1.6 or 1.5 would generally suit as a rough value increase (Canon uses 1.6 crop cameras whilst Nikon uses 1.5 - although the difference there for usable shutter speeds will be negligible for most people).

Remember its only a guideline its not a hard-fast rule so do some tests and see how you go. Some people can shoot fat slower, whilst others need to have a faster shutter speed.

 

[lennon33x]

But then on an FX, you're at 1/50.

1 / ([amount the final image will be cropped versus a full frame] x [focal length] x 2)

how in the world are you supposed to know that? Seems to me that if you capture something as sharp as it's going to be captured, that decreasing the shutter speed further is not going to matter, no matter how much you crop.

if anything it should be: 1 / ( [focal length] x [2 + ([MP - 16] / 10) ] )*

Where a 36MP camera would be 1 / FL x 4
and a 24MP camera would be 1 / FL x 2.8

The formula is for trying to pick the shutter speed that will result in a tact sharp capture, beyond that crop at will, right?


*I realize my formula is completely flawed.

It's just a rule of thumb.

1/1.6-2x focal length.

 

[astroNikon]

1 * tweak the settings to get the exposure you want

 

[Braineack]

1 * tweak the settings to get the exposure you want

I'm more of 1 / (FL x 4) and AUTO-FP on.

 

[SmokyMtnHiker]

I think it was focal length rather than aperture.

In short, yes, there is a relationship, but it has to do with exposure, not camera shake.

So to clarify; generally, you would not want to take a hand-held shot with any shutter speed slower than the inverse of the focal length. (ex.) hand-held shot, 50mm lens: 1/50 second, maximum.

Yeah! Thats what is was! Thanks.

 

[robbins.photo]

1 / ([amount the final image will be cropped versus a full frame] x [focal length] x 2)

how in the world are you supposed to know that? Seems to me that if you capture something as sharp as it's going to be captured, that decreasing the shutter speed further is not going to matter, no matter how much you crop.

if anything it should be: 1 / ( [focal length] x [2 + ([MP - 16] / 10) ] )*

Where a 36MP camera would be 1 / FL x 4
and a 24MP camera would be 1 / FL x 2.8

The formula is for trying to pick the shutter speed that will result in a tact sharp capture, beyond that crop at will, right?


*I realize my formula is completely flawed.

It's just a rule of thumb.

1/1.6-2x focal length.

So since I'm all thumbs I should be using 1/2000 whenever I'm shooting my 70-200 mm? Cool.. thanks.. lol.

 

[lennon33x]

So since I'm all thumbs I should be using 1/2000 whenever I'm shooting my 70-200 mm? Cool.. thanks.. lol.

No, you need something faster. Like the EOS 1D Mk I - 1/16000


And who the eff needs a shutter speed THAT fast?

 

[Braineack]

So since I'm all thumbs I should be using 1/2000 whenever I'm shooting my 70-200 mm? Cool.. thanks.. lol.

No, you need something faster. Like the EOS 1D Mk I - 1/16000


And who the eff needs a shutter speed THAT fast?

When you want to get a portrait of the sun, but you want the rest the of universe in the bg out of focus.

 

[Gavjenks]

When you want to get a portrait of the sun, but you want the rest the of universe in the bg out of focus.

Sadly, even at f/1.0 and a 1200mm lens, everything from 75 kilometers out will still be in focus if you focus on the sun (which is at 146,000,000 kilometers).


I considered actually calculating the required f/stop for a sun taking up half the sensor, for giggles, but it got too complicated too quickly. Probably something like f/0.0001 or whatever, and some sort of lens the size of Jupiter.

 

[astroNikon]

When you want to get a portrait of the sun, but you want the rest the of universe in the bg out of focus.

Sadly, even at f/1.0 and a 1200mm lens, everything from 75 kilometers out will still be in focus if you focus on the sun (which is at 146,000,000 kilometers).


I considered actually calculating the required f/stop for a sun taking up half the sensor, for giggles, but it got too complicated too quickly. Probably something like f/0.0001 or whatever, and some sort of lens the size of Jupiter.

would that be a Gimbel mount that you would need for that lens the size of Jupiter ?
:thumbup:

 

[runnah]

When you want to get a portrait of the sun, but you want the rest the of universe in the bg out of focus.

Sadly, even at f/1.0 and a 1200mm lens, everything from 75 kilometers out will still be in focus if you focus on the sun (which is at 146,000,000 kilometers).


I considered actually calculating the required f/stop for a sun taking up half the sensor, for giggles, but it got too complicated too quickly. Probably something like f/0.0001 or whatever, and some sort of lens the size of Jupiter.

would that be a Gimbel mount that you would need for that lens the size of Jupiter ?
:thumbup:

Free hand like a boss.