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Author Topic: Manual, Auto ISO, and Flash- how does this work?  (Read 7004 times)

scottkinfw

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Manual, Auto ISO, and Flash- how does this work?
« on: March 29, 2014, 03:40:26 PM »
I am going to shoot a the cattle drive in Fort Worth, TX today at 4PM, which of course is outdoors.  This occurs on most weekends at 11 AM and 4PM.  I have shot this before but obviously, the timing of the event isn't the best for lighting.  Specifically, there is a lot of contrast not only in the longhorn color, but also the shadows and bright sunlight areas (obviously).  Today I am going to try to shoot again, this time with my new (yippie ky eyeee) 300 2.8 IS II lens on my 5DII body.

In thinking about how to augment the shadows, I though I would use a better beamer for fill and set flash to ETTL  (using a single 580 EXII).  I haven't used auto ISO, so I thought I would try that with appropriate manual camera settings.

I would appreciate if anyone can provide me insight for this situation.  How does this work?  Will the flash control the ISO?  What will the camera logically use as priority to set the ISO?  Should I make exposure compensation changes or set the flash to manual?  I could just set it and forget it I guess, but I really want to understand what is going on inside the camera.

To all who answer, I thank you in advance.

sek
Cameras: 1DXII,5D III, 5D II.  Lenses    24-70 2.8L II IS, 70-200 f4L IS, 70-200 f2.8L IS II, EF 400 5.6L, 300 2.8 IS II, Samyang 14 mm 2.8.   Flashes: 600EX-RT X 2, ST-E3-RT, 580 EX II.
Plus lots of stuff that just didn't work for me

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Manual, Auto ISO, and Flash- how does this work?
« on: March 29, 2014, 03:40:26 PM »

ahab1372

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Re: Manual, Auto ISO, and Flash- how does this work?
« Reply #1 on: March 29, 2014, 03:49:12 PM »
I haven't tried in a while, but I believe Auto ISO will be set to 400 when using on camera flash. That is probably not what you want it to do in this case.

neuroanatomist

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Re: Manual, Auto ISO, and Flash- how does this work?
« Reply #2 on: March 29, 2014, 04:12:44 PM »
ISO is fixed at 400 with flash. I assume you want to be using action-stopping shutter speeds, which means you also need to use H mSS on your flash.  Even with the power loss from that, you'll have enough for fill with the better beamer.
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scottkinfw

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Re: Manual, Auto ISO, and Flash- how does this work?
« Reply #3 on: March 30, 2014, 04:38:24 AM »
Here is what I discovered. 

I initially set the camera on manual with auto ISO, flash to ETTL. The flash was always set to HSS.  The ISO WAS fixed at 400.

The pics were way over exposed so I went to manual and set ISO to around 160, played with settings until I got a good exposure.  I also lowered the flash output as needed. 

So here are some sample shots.

Cameras: 1DXII,5D III, 5D II.  Lenses    24-70 2.8L II IS, 70-200 f4L IS, 70-200 f2.8L IS II, EF 400 5.6L, 300 2.8 IS II, Samyang 14 mm 2.8.   Flashes: 600EX-RT X 2, ST-E3-RT, 580 EX II.
Plus lots of stuff that just didn't work for me

scottkinfw

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Re: Manual, Auto ISO, and Flash- how does this work?
« Reply #4 on: March 30, 2014, 04:41:14 AM »
Here are a few more

Here is what I discovered. 

I initially set the camera on manual with auto ISO, flash to ETTL. The flash was always set to HSS.  The ISO WAS fixed at 400.

The pics were way over exposed so I went to manual and set ISO to around 160, played with settings until I got a good exposure.  I also lowered the flash output as needed. 

So here are some sample shots.
Cameras: 1DXII,5D III, 5D II.  Lenses    24-70 2.8L II IS, 70-200 f4L IS, 70-200 f2.8L IS II, EF 400 5.6L, 300 2.8 IS II, Samyang 14 mm 2.8.   Flashes: 600EX-RT X 2, ST-E3-RT, 580 EX II.
Plus lots of stuff that just didn't work for me

scottkinfw

  • EOS 5DS R
  • ******
  • Posts: 1466
  • Wildlife photography is my passion
    • www.kasden.smug.com
Re: Manual, Auto ISO, and Flash- how does this work?
« Reply #5 on: March 30, 2014, 04:41:59 AM »
And finally, bringing up the rear

Here are a few more

Here is what I discovered. 

I initially set the camera on manual with auto ISO, flash to ETTL. The flash was always set to HSS.  The ISO WAS fixed at 400.

The pics were way over exposed so I went to manual and set ISO to around 160, played with settings until I got a good exposure.  I also lowered the flash output as needed. 

So here are some sample shots.
Cameras: 1DXII,5D III, 5D II.  Lenses    24-70 2.8L II IS, 70-200 f4L IS, 70-200 f2.8L IS II, EF 400 5.6L, 300 2.8 IS II, Samyang 14 mm 2.8.   Flashes: 600EX-RT X 2, ST-E3-RT, 580 EX II.
Plus lots of stuff that just didn't work for me

neuroanatomist

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Re: Manual, Auto ISO, and Flash- how does this work?
« Reply #6 on: March 30, 2014, 07:18:05 AM »
Nice! :)
EOS 1D X, EOS M6, lots of lenses
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Re: Manual, Auto ISO, and Flash- how does this work?
« Reply #6 on: March 30, 2014, 07:18:05 AM »

ahab1372

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Re: Manual, Auto ISO, and Flash- how does this work?
« Reply #7 on: March 30, 2014, 01:17:21 PM »
I agree, nice job. Thanks for sharing.

Marsu42

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Re: Manual, Auto ISO, and Flash- how does this work?
« Reply #8 on: March 30, 2014, 03:46:47 PM »
I would appreciate if anyone can provide me insight for this situation.  How does this work?

Use Magic Lantern, the stable v2.3 or a wip auto_iso module for nightly (incidentally written by me :-)) fixes this braindead crippling... 2/3rd of my shots are taken with flash+autoiso. The module also adds ec in m which is otherwise only available on 1dx.

scottkinfw

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Re: Manual, Auto ISO, and Flash- how does this work?
« Reply #9 on: March 30, 2014, 08:41:03 PM »
Thanks Marsu42.

I learned a lot, hopefully, others did too.

sek
Cameras: 1DXII,5D III, 5D II.  Lenses    24-70 2.8L II IS, 70-200 f4L IS, 70-200 f2.8L IS II, EF 400 5.6L, 300 2.8 IS II, Samyang 14 mm 2.8.   Flashes: 600EX-RT X 2, ST-E3-RT, 580 EX II.
Plus lots of stuff that just didn't work for me

Mt Spokane Photography

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Re: Manual, Auto ISO, and Flash- how does this work?
« Reply #10 on: March 30, 2014, 09:10:15 PM »
Using a better beamer throws off any auto setting, and Magic Lantern will not correct this.
 
Doing it the way you did is fine.
 
You can also use your better beamer with TV and exposure compensation.

Marsu42

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Re: Manual, Auto ISO, and Flash- how does this work?
« Reply #11 on: March 31, 2014, 01:29:52 AM »
Using a better beamer throws off any auto setting, and Magic Lantern will not correct this.

Ugh? Why's that? I'm not using the better beamer but the 600rt @200mm zoom, and at least that works just fine with ML, auto iso and ettl.

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Re: Manual, Auto ISO, and Flash- how does this work?
« Reply #11 on: March 31, 2014, 01:29:52 AM »