Before the rush

Before the rush
by evan-pak

Submit your Photo
Hall of Fame

Please participate in Meta
and help us grow.

Photography Stack Exchange is a question and answer site for professional, enthusiast and amateur photographers. Join them; it only takes a minute:

Sign up
Here's how it works:
  1. Anybody can ask a question
  2. Anybody can answer
  3. The best answers are voted up and rise to the top

I am trying to stop using the auto mode. I think I sort of understand the following ISO rules:

  • Use an ISO of 100 or 200 when taking photographs outside in sunny conditions.
  • If the sky is overcast or it is evening time, then use an ISO within the range of 400 to 800.
  • Night time or in cases of low light you might need to set your digital camera ISO to 1600.

Should I follow the same rules when using a flash (direct/bounce mode)?

share|improve this question
up vote 2 down vote accepted

When you use flash outside in sunny conditions to fill shadows you should set it to a low value. When you use flash in low light and you want to illuminate just your model, it's better to use low iso values. If you want to illuminate the model and the scene you should use a higher iso value like 400 and up (the value depends on light and model of camera). For more information, have a look at:

share|improve this answer
do the same suggestions apply to bounce mode? – Max C Mar 10 '13 at 17:15
Essentially there is no difference between direct flash and bounce flash in this respect, although the flash has to work much harder if you bounce it because the light is spread out more so less of it falls on the subject. My approach to indoors flash, for the record, is to set ISO/shutter/aperture to whatever combination gives me the desired exposure for the background, and then add flash to give proper illumination to the foreground. This means that I don't actually pump the flash all that hard, as the overall exposure is in the ballpark to begin with. This gives a shorter flash recharge. – Staale S Mar 11 '13 at 14:19

I would say "no, do not use the same rules" - but that's because I wouldn't use your rules when not using flash. In most circumstances, I think you should start by selecting the shutter speed and/or aperture that you want, and then use the lowest ISO which allows you to expose the scene correctly. I can't think of many circumstances where I would choose the ISO before choosing other things.

share|improve this answer
"I can't think of many circumstances where I would choose the ISO before choosing other things." Except film photography! – James Nov 20 '14 at 0:45

flash is, imo, a lot trickier to set a rule around. it really is dependant on how you want the shot to turn out.

in low light, if you set to iso 100, 1/50 sec, flash on, the background scene will be dark/near black. there is a certain look some ppl like about the way that is shot but be wary of blowing out your subject unless you have a diffuser.

in low light, my preference with flash is to iso 100, 1/15, f1.8. this opens the shutter longer allowing the flash to freeze my subject while allowing the slow shutter to show up in a nicely lit ambient mood. as you move to iso 200++, this allows your shutter to be set faster without motion blur if your subject moves while still pulling up the ambiance. But that is entirely up to you as the slower shutter opens up some veryy creative motion blur with flash photography.

flash photography isnt as easy to "can" in respect to settings so while my rule may work for me, you may find it is inappropriate to your stylr or taste.

share|improve this answer

Your Answer


By posting your answer, you agree to the privacy policy and terms of service.

Not the answer you're looking for? Browse other questions tagged or ask your own question.