Shutter Speed

Anyone know why shooting in tv mode today i wanted a slow shutter speed,but at 1/30 the f/number was flashing on 22,can anyone advise me please,i was using the 400D and the Sigma 18-50 Thank you ...Ray

Let me guess: the Sigma's smallest aperture is f/22.

The flashing means the camera needed a smaller aperture than f/22 for proper exposure at 1/30.

The "sunny 16" rule predicts that in full sun at ISO 100 you'd need 1/100 at f/16. Or 1/50 at f/22.

If your ISO is already as low as it'll go, your next step is to get a neutral density filter.

-js

You need to remember the 3 ways to control light....shutter speed, aperature, and ISO/ASA ( the old film speed, the new is sensitivity of computer chip). You most likely needed to change the ISO to a lower number to make less sensitive. You aperature at that setting yields a great depth of field and people rarely shoot at this level. Do you know ywhat your iso setting was??

That was the slowest the camera could go with stopping all the way to f/22 with the selected ISO. Either pick a lower ISO or use a neutral density filter over the lens to limit the amount of light entering the lens.

number six wrote in post #3908196
Let me guess: the Sigma's smallest aperture is f/22.

The flashing means the camera needed a smaller aperture than f/22 for proper exposure at 1/30.

The "sunny 16" rule predicts that in full sun at ISO 100 you'd need 1/100 at f/16. Or 1/50 at f/22.

If your ISO is already as low as it'll go, your next step is to get a neutral density filter.

-js

yes the iso was 100

must have been bright out....only other solution would be neutral density filter as mentioned above

jcpoulin wrote in post #3908263
must have been bright out....only other solution would be neutral density filter as mentioned above

Or throw a polarizer on there - that's good for at least a stop and a half.

Mark

good point mark, always forget about this option

Thank you to all for taking the time to help me,i think i understand now,by the way it was very bright...Ray