How should I focus

[Cutter]

Originally Posted by Drew Smith

Mark - you put in the ISO you'll be shooting at (or hope to be shooting at) then the aperture in the same way (what you hope/expect to be using) and the Guide Number is the flash name/number you are using. In your case the 580ex, but you drop the '0' - your guide number is 58.

So, as I said earlier, if you shoot at iso 100 and an aperture of 1, it should give you a flash distance of 58 meters.

For your lens at f2.8, ISO 100, it gives you 20 meters effective distance, and so on..

put the numbers in pressed calculate and still nothing, iso 100, f2,8 guide no 58

[ianpinion]

Mark, I think what you may have done is enter the aperture value as 2,8 not 2.8

...it won't work with a comma separating the two integers, it has to be a full-stop!

Trust me, I've just tried it again

[Cutter]

Originally Posted by ianpinion

Mark, I think what you may have done is enter the aperture value as 2,8 not 2.8

...it won't work with a comma separating the two integers, it has to be a full-stop!

Trust me, I've just tried it again

No that was just a typing error in the thread, still doesnt work

[ianpinion]

Can you post a screen shot, Mark, because it works for me everytime and I'm now baffled as to why it won't for you.

[Baffled]

Hi Mark, Really interesting thread. I tried as follows and it worked:-

Choose the ISO; Enter guide No 58; Enter Aperture then scroll down the Units Box to choose Metres or Feet and finally click on the little Red calculate button. The Range should appear in the last window.
Well done for getting through to the regional finals of the competition

_______
John

[Cutter]

Just done it in my phone and works ok, strange

[ianpinion]

I wonder then whether you've got a problem with FlashPlayer on your computer, Mark.

[Cutter]

Ok guys I have found out that I can use flash on the catwalk, so if use I my 70-200 2.8 and my 580mk2 flash how would you set it up so as to get enough ambient light to get the atmosphere but get the right fill in for the model?
This is what I think I should do, use manual on camera and an app of about f4 to get the clothes in the dof. Put the flash on through the lens metering ie ttl. to fill in, is that ok or am I missing something ?

[ianpinion]

That sounds about right Mark, just be sure to use either spot metering or centre weighted, otherwise the spotlights over the fashion runway could cause your camera to underexpose if you left it on full evalulative.

[Cutter]

Originally Posted by ianpinion

That sounds about right Mark, just be sure to use either spot metering or centre weighted, otherwise the spotlights over the fashion runway could cause your camera to underexpose if you left it on full evalulative.

Thanks Ian hoped you would get back to me. Oh and forgot to say have a ss of at least
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