Wide angle close focus with TTL question

[Interceptor121]

Metering is just a guideline on land as it is underwater

 

[ReadyDiverOne]

@Nemrod thanks much, very helpful. I have the RX100 with 2 YS-D2s so can go as fast as I want on the shutter. W/r/t regular wide angle shots at depth, I find that my background is frequently too dark. Given that I'm usually shooting at about 1/125 and don't want to go too too much lower/slower on speed, and let's say aperture is F8, do you have a view on whether it is better to lower/open the aperture or to raise ISO? I understand composition/DoF matters, but wondering what your (and others') thoughts are on this. I've read that raising ISO can create issues as strobes will blow out more.

Thanks.

 

[JackConnick]

Firing the strobes into the blue doesn't matter.

Remember that the background is primarily controlled with shutter speed, foreground primarily with aperture and strobes. ISO changes it all.

I shoot an FX D850 with high dynamic range. However it's high resolution requires that I stop down to about f/11 at a minimum to gain enough sharpness overall. I can go as high as 1/320, but syncing at the highest shutter speed can be problematic/inconsistent so I usually shoot at 1/250th a sec.

You have more latitude with your RX100, but less dynamic range, so you'll need to watch your 1/4 and 3/4 tones, ie the lighter and darker areas to keep them open.

Using your histogram to evaluate your shooting as you go is important, you can't trust your view screen.

Shooting your strobes on manual is important as you need to adjust them for their position as subject matter to get an even exposure.

You may also want to refer to our other free Handbook on Strobe Positioning.

Jack

 

[ReadyDiverOne]

@JackConnick thanks much, I did check out your strobe positioning piece, also very helpful.

Re metering, histogram, highs and lows, pls help me understand: I have always read that one wants to under expose the background at least a stop or two in order to get that nice blue color. Is that still true? If it is, then does one use the live histogram (available on the RX100 display/viewfinder) to confirm that most of the data is to the left, hence underexposed? On my RX100, the meter is -2, -1, 0, +1, +2, with 1/3 increments, each representing a stop (right?). I'm usually at least at -1.

Thanks.

 

[Nemrod]

@Nemrod thanks much, very helpful. I have the RX100 with 2 YS-D2s so can go as fast as I want on the shutter. W/r/t regular wide angle shots at depth, I find that my background is frequently too dark. Given that I'm usually shooting at about 1/125 and don't want to go too too much lower/slower on speed, and let's say aperture is F8, do you have a view on whether it is better to lower/open the aperture or to raise ISO? I understand composition/DoF matters, but wondering what your (and others') thoughts are on this. I've read that raising ISO can create issues as strobes will blow out more.

Thanks.

I think I would raise the ISO a bit to brighten the water. Then drop the power down on the strobes to compensate for the subject exposure. If need be then use a diffuser to further reduce output if you are bottomed out. I think your RX100 maxes out at f8?

And/or move back. If you are framed at three feet then move back to four feet and zoom to keep framing. I assume you are using some sort of wet optic wide angle lens, some allow zoom through, others do not?

Put your camera in Manual and put your strobes in Manual. The sTTL will not like CFWA, too much contrast between subject and background. It may work sometimes, other times not.

James

 

[Interceptor121]

Just use the shutter that gives you the blue you want. The camera has 1" sensor shoot at ISO 100 you have powerful strobes there is no need to raise the ISO
And maybe stop reading posts about best settings!

 

[stuartv]

To date, I have only been shooting full Manual. I start with guesstimated settings. I don't meter anything. As soon as I get to the bottom, I take a test shot, review it, adjust settings, repeat, until I get the background water to the color I want. Then I adjust my strobe power for a good exposure at the distance I expect my subjects to be. Once there, I may make small tweaks to my settings during the course of the dive as/if conditions change.

Standard stuff.

I just got my first TTL setup. After some land-based testing, what I think will work is the same as above, but with the following changes:

Strobes (Z240s) in TTL mode (instead of Manual mode)
Camera set to have Exposure metering follow the Focus point

Everything else stays the same. I have verified through land-based testing that my camera will still shoot TTL and adjust strobe power correctly, even if the camera is in Manual, including an explicit ISO. If the camera meters correctly for the spot I have the camera focused on then I am, well, hopeful, that it will give me a good exposure.

All cameras may not have the setting option for exposure metering to follow focus point, but my Sony a7rIV does. I suppose it's also possible that not all cameras will do TTL flash metering when everything else is full manual. I don't know.

I figure I may still have to adjust things as I try it and take some photos. For example, I can imagine situations where I may have to increase the ISO and change my other settings to suit, to preserve the background color, while allowing the strobes to fire at a lower power level, for any of several reasons.

I can't wait to get in the water and work on it!

 

[Nemrod]

The reason I said to possibly raise the ISO is that I understood he was at his minimum desired shutter speed. Maybe he has shaky hands! Yes, I would preferably drop the shutter speed to brighten the water background until it has dropped until the resulting speed is no longer practical for the conditions. Generally 1/60 will stop most action and is fast enough for general shooting. So, that would be my floor, even 1/30 in some cases.

And yes, I too am not a believer in best settings. The best setting is the one that gives you what you want in that time and place and that photo.

I believe the RX can do sTTL in camera Manual and strobes in sTTL, the OP will need to look in his OM. Not familiar with YS or S&S strobes and sTTL. The A6000 series does have and allow TTL in camera Manual mode. Then there is the UT trigger we two have which has additional options not relevant unfortunately to the RX series cameras.

Hey, Mr. Sony, give me a new RX with interchangeable lenses (12mm-36mm zoom, 10mm WA and a 50mm prime) and a fisheye converter and a teleconverter, one inch sensor and a hot shoe! Oh, throw in full manual flash with no pre-flash too. Thank you.

James

 

[ReadyDiverOne]

@stuartv and @Nemrod thanks!

First: I don't have shaky hands but always wonder about motion blur going down to 1/60th, I will definitely try that as I def prefer to adjust shutter before ISO.

Second, @stuartv your approach is exactly mine--descend, take practice/sample shot(s), dial in background, adjust strobe output and position, SHOOT! I asked about this pro photographer idea because I'd never heard of it before. (@Interceptor121, the pro also strongly recommended adjusting ISO quite a lot--which I had always heard/read was the last of the three (shutter/aperture/ISO) one should adjust. So I found that quite weird.)

Third, I've tried TTL with the RX100 and maybe I'm doing something wrong but it hasn't worked well for me at all. Pix come out way over-exposed.

Anyone out there found a way to make YS-D2s work on TTL with RX100? Can that even be done shooting manual?

Thanks again.

 

[ReadyDiverOne]

Re metering, histogram, highs and lows, pls help me understand: I have always read that one wants to under expose the background at least a stop or two in order to get that nice blue color. Is that still true? If it is, then does one use the live histogram (available on the RX100 display/viewfinder) to confirm that most of the data is to the left, hence underexposed? On my RX100, the meter is -2, -1, 0, +1, +2, with 1/3 increments, each representing a stop (right?). I'm usually at least at -1.

Still looking for an answer on this, particularly re reading the live histo. Thanks.