Archive 2024A9 III + Godox Flash

aCuria wrote:

GMPhotography wrote

See If I can put this in perspective to actually shooting . Let's say you have a group shot of 5 people in strong sunlight in the background and hitting them from behind so you need fill light. Today your shutter speed and sync speed is no greater than 1/250 of a second at lets say you want F8 to shoot at. Well F8 and 1/250 will not bring down the ambient light to match your flash output. Now lets say you can get F8 out of the flash but you cant't get the shutter speed faster with the global shutter now you can so lets say that balance point is 1/8000 sync speed. So you dropped the ambient light into that F8 zone. Remember the shutter speed is ambient light hitting the subject the Flash is basically the aperture setting to get F8 . So in essence you can balance this scenario better. Today you have to blast them with a flash that has to get to F16 at 1/250 sync speed to balance it out. So you need a lot of power, with global shutter you cut that need out as now you can balance the ambient light much better with shutter speed and drop the scene into that flash F8 zone you want to shoot at. Fo my 50 years I would have killed for this ability along with everyone on the planet. This is a big deal especially to commercial shooters and wedding shooters not to mention every hobbyist out there that did not buy 4 grand in lighting gear to get huge amount of flash power.

Now im still trying to understand the lingo here but this scenario is what you really want out of the global shutter at least in the flash area. Now we have the ability to raise the sync speed to match our flash output. In this scenario global shutter is controlling the Ambient light and Flash controls the aperture.

I want to try this really badly

Don't get too excited, global shutter + flash as of 2/2024 represents "unrealized potential".

This is because the kinds of strobes we need to make full use of global shutter do not exist!

Lets have a simple example:

1. suppose foreground exposure is good at 50ws (1/200s, iso 100)
   
2. but background exposure needs to be cut by 3 stops
   
3. Normally we use a 3 stop ND, but this means a big 400ws strobe is needed (50ws after punching through 3 stop ND)
   
4. Or HSS is used but a big strobe is needed once again
   
5. Now we can use an A9III, and push the shutter up by 4.25 stops (1/4000s) (3 stops to match the ND, +1.25 stop because base iso is 250) and theoretically use a 50ws strobe! this is what we want, get good results with just a speedlight.
   

However, this does not actually work because we need a strobe that emits 50ws at a T0.1 of 1/4000s

Now compare that to to the strobes we actually have:

1. Broncolor 800L - 3ws at 1/4580s and 6ws at 1/3000s
   
2. Profoto B1X - 16ws at 1/4780s or 32ws at 1/3800s
   
3. Godox AD600 pro - 31.3ws at 1/4090s
   
4. Godox AD400 pro - 25ws at 1/3930s
   
5. Godox AD200 pro - 12.5ws at 1/5630s or 25ws at 1/3420s
   

Ultimately this means we will still have to carry around big strobes because the small ones do not emit enough light at high sync speeds.... Docusync was using the AD1200

What we need is for someone to make a speedlight capable of outputting 70ws, but this 70ws needs to come out at a T0.1 of at least , 1/4000s preferably even faster.
...Show more →

I haven't looked at the math behind any of this but how is it do you think that at 1/16000s I can use the GN60 flash at 1/32 or perhaps it was 1/128 or even 1/256 (I can't recall exactly) to brightly light up a bird at 4 meters.

I was not expecting to get any light on the subject because at 1/16000s I figured the flash power would be so severely reduced it would be useless. That didn't seem to be the case.

Are you sure your assumptions work if you are able to adjust the timing so you get the peak output to coincide with the shutter. Isn't T0.1 power rating incorrect if the flash timing is delayed.

aCuria wrote:

GMPhotography wrote

See If I can put this in perspective to actually shooting . Let's say you have a group shot of 5 people in strong sunlight in the background and hitting them from behind so you need fill light. Today your shutter speed and sync speed is no greater than 1/250 of a second at lets say you want F8 to shoot at. Well F8 and 1/250 will not bring down the ambient light to match your flash output. Now lets say you can get F8 out of the flash but you cant't get the shutter speed faster with the global shutter now you can so lets say that balance point is 1/8000 sync speed. So you dropped the ambient light into that F8 zone. Remember the shutter speed is ambient light hitting the subject the Flash is basically the aperture setting to get F8 . So in essence you can balance this scenario better. Today you have to blast them with a flash that has to get to F16 at 1/250 sync speed to balance it out. So you need a lot of power, with global shutter you cut that need out as now you can balance the ambient light much better with shutter speed and drop the scene into that flash F8 zone you want to shoot at. Fo my 50 years I would have killed for this ability along with everyone on the planet. This is a big deal especially to commercial shooters and wedding shooters not to mention every hobbyist out there that did not buy 4 grand in lighting gear to get huge amount of flash power.

Now im still trying to understand the lingo here but this scenario is what you really want out of the global shutter at least in the flash area. Now we have the ability to raise the sync speed to match our flash output. In this scenario global shutter is controlling the Ambient light and Flash controls the aperture.

I want to try this really badly

Don't get too excited, global shutter + flash as of 2/2024 represents "unrealized potential".

This is because the kinds of strobes we need to make full use of global shutter do not exist!

Lets have a simple example:

1. suppose foreground exposure is good at 50ws (1/200s, iso 100)
   
2. but background exposure needs to be cut by 3 stops
   
3. Normally we use a 3 stop ND, but this means a big 400ws strobe is needed (50ws after punching through 3 stop ND)
   
4. Or HSS is used but a big strobe is needed once again
   
5. Now we can use an A9III, and push the shutter up by 4.25 stops (1/4000s) (3 stops to match the ND, +1.25 stop because base iso is 250) and theoretically use a 50ws strobe! this is what we want, get good results with just a speedlight.
   

However, this does not actually work because we need a strobe that emits 50ws at a T0.1 of 1/4000s

Now compare that to to the strobes we actually have:

1. Broncolor 800L - 3ws at 1/4580s and 6ws at 1/3000s
   
2. Profoto B1X - 16ws at 1/4780s or 32ws at 1/3800s
   
3. Godox AD600 pro - 31.3ws at 1/4090s
   
4. Godox AD400 pro - 25ws at 1/3930s
   
5. Godox AD200 pro - 12.5ws at 1/5630s or 25ws at 1/3420s
   

Ultimately this means we will still have to carry around big strobes because the small ones do not emit enough light at high sync speeds.... Docusync was using the AD1200

What we need is for someone to make a speedlight capable of outputting 70ws, but this 70ws needs to come out at a T0.1 of at least 1/4000s but preferably even faster.
...Show more →

Thank you for the reality check.

aCuria wrote:

GMPhotography wrote

See If I can put this in perspective to actually shooting . Let's say you have a group shot of 5 people in strong sunlight in the background and hitting them from behind so you need fill light. Today your shutter speed and sync speed is no greater than 1/250 of a second at lets say you want F8 to shoot at. Well F8 and 1/250 will not bring down the ambient light to match your flash output. Now lets say you can get F8 out of the flash but you cant't get the shutter speed faster with the global shutter now you can so lets say that balance point is 1/8000 sync speed. So you dropped the ambient light into that F8 zone. Remember the shutter speed is ambient light hitting the subject the Flash is basically the aperture setting to get F8 . So in essence you can balance this scenario better. Today you have to blast them with a flash that has to get to F16 at 1/250 sync speed to balance it out. So you need a lot of power, with global shutter you cut that need out as now you can balance the ambient light much better with shutter speed and drop the scene into that flash F8 zone you want to shoot at. Fo my 50 years I would have killed for this ability along with everyone on the planet. This is a big deal especially to commercial shooters and wedding shooters not to mention every hobbyist out there that did not buy 4 grand in lighting gear to get huge amount of flash power.

Now im still trying to understand the lingo here but this scenario is what you really want out of the global shutter at least in the flash area. Now we have the ability to raise the sync speed to match our flash output. In this scenario global shutter is controlling the Ambient light and Flash controls the aperture.

I want to try this really badly

Don't get too excited, global shutter + flash as of 2/2024 represents "unrealized potential".

This is because the kinds of strobes we need to make full use of global shutter do not exist!

Lets have a simple example:

1. suppose foreground exposure is good at 50ws (1/200s, iso 100)
   
2. but background exposure needs to be cut by 3 stops
   
3. Normally we use a 3 stop ND, but this means a big 400ws strobe is needed (50ws after punching through 3 stop ND)
   
4. Or HSS is used but a big strobe is needed once again
   
5. Now we can use an A9III, and push the shutter up by 4.25 stops (1/4000s) (3 stops to match the ND, +1.25 stop because base iso is 250) and theoretically use a 50ws strobe! this is what we want, get good results with just a speedlight.
   

However, this does not actually work because we need a strobe that emits 50ws at a T0.1 of 1/4000s

Now compare that to to the strobes we actually have:

1. Broncolor 800L - 3ws at 1/4580s and 6ws at 1/3000s
   
2. Profoto B1X - 16ws at 1/4780s or 32ws at 1/3800s
   
3. Godox AD600 pro - 31.3ws at 1/4090s
   
4. Godox AD400 pro - 25ws at 1/3930s
   
5. Godox AD200 pro - 12.5ws at 1/5630s or 25ws at 1/3420s
   

Ultimately this means we will still have to carry around big strobes because the small ones do not emit enough light at high sync speeds.... Docusync was using the AD1200

What we need is for someone to make a speedlight capable of outputting 70ws, but this 70ws needs to come out at a T0.1 of at least 1/4000s but preferably even faster.
...Show more →

Needing 50-70ws with a t0.1 faster than 1/4000s is, IMO, not very common. I am using an on-location lighting scenario.

Following the Sunny 16 rule, a shutter speed of 1/4000s is equivalent to shooting under bright daylight at f/4 ISO 250. Taking the Godox V1 with a Guide Number of 92' at the 50mm setting, the appropriate flash-to-subject distance at full power, ISO 250, and f/4 is 32'. For a landscape shot framing a full body of a 5'7" person using a 50mm lens, a camera-to-subject distance of about 11.6' is needed (assuming it is the same as the flash-to-subject distance). Halving the 32' flash distance (16') for a looser framing of a full body would reduce the required output to 1/4 full power. Although I do not have the flash duration for the Godox V1 at 1/4 power (25ws), the similar AD100 Pro was measured at 1/3020s t0.1 by Robert Hall, suggesting it is reasonably close to the 1/4000s SS. Adjusting the framing or using accessories like a Clic Magnum or fresnel to zoom in could further reduce the power and quicken the flash duration. Unless you intend to underexpose a sunny background by 1-2 stops (1/8000s-1/16000s at f/4) or throw light from further away on a sunny day, achieving this may be possible with just the AD100 Pro. Lower ambient light would provide even more flexibility.

Consequently, I find the GS feature on the A9III quite useful in most situations with standard equipment. However, in some extreme cases, regardless of High-Speed Sync or Global Shutter, a larger strobe becomes necessary.