stupid question time

D

DinoS

Hmmmmm.......Paste!
Suspended / Banned
Messages
2,823
Edit My Images
Yes
if i have a lens set at 300mm and one at 55mm. both at aperture F5.6. will the one at 300mm have a longer shutter speed as it has less light getting into it although the aperature is the same.
 
nope
the same
that's why it's f/xx
focal length divided by xx
so
300mm f/5.6 has a diameter of 53.6mm (approx)
55mm f/5.6 has a diameter of 9.8mm (approx)
but they both let through the same amount of light
so both need same shutter speed for exposure

now, can you hold them both steady at the same shutter speed - nope
300mm needs approx 1/300
55mm needs approx 1/50
to avoid camera shake
 
hi

i took two images twoday same place on tripod different lenses.

55mm- 1/250 F5.6

300mm 1/125 F5.6


WHY?
 
F8 is f 8 is f8 is f8 - regardless of the lens and how big the front element actually is. :)

Several possible reasons for that 1 stop difference, but the most likely is that the 300mm was metering a much smaller field of view than the 55mm, which was overall, a stop darker when 'analysed 'by the metering system.
 
maybe the lighting changed?
or as CT says the metering field of view will be different
were you using spot or what?
 
i do not know it was full auto
i took the 55mm after the 300mm so theretically the 55mm should be slower
 
it's more than likely that the view at 300mm contained more dark areas than light e.g. less sky, hence the slower shutter speed.
 
oh thank you.

i am trying to take pictures of badminton players but my images are blurring.

how an i stop that apart from buying a new lens
 
You need to keep that shutter speed up to stop blurring. Higher ISOs let you take photos at higher shutter speeds aswel (don't put it right up to 1600 tho, too much grain).
 
400duser said:
i am trying to take pictures of badminton players but my images are blurring.

how an i stop that apart from buying a new lens
Click to expand...
If you don't know what's making them blurred, then buying a lens won't help.

There are at least 3 different reasons why the photos might be blurred:
1. You're not focussing accurately - especially if you're using the camera in automatic mode, because then it tries to decide what it thinks you want in focus, and how does it know?
2. The shutter speed is too slow and you are experiencing camera shake.
3. The shutter speed is fast enough to avoid camera shake, but not fast enough to "freeze" the action.

Show us some examples. Tell us how you took them (equipment, focal length, exposure mode, focus mode, etc. etc.) A picture is worth a thousand words and we'll be able to diagnose what's going wrong. Without pictures we're just guessing.
 
You must log in or register to reply here.
Back
Top