When the Olympus TG-6 Tough camera was released one of the features that some people talked about as an improvement on the TG-5 was an ability to set a limit on the lowest shutter speed. With there not being a direct way of setting the shutter speed on the TG5 or TG6 this was seen by many as a step forward.

But when I first put the Lowest S/S Setting to the test it didn’t seem to bring much if any advantage.

To find this setting in the TG6’s menu go to menu C in the Custom Menu, select ISO Auto Set and you’ll then have two options one is the Upper Limit and Default for the Auto ISO range and the other is to set the Lowest S/S Setting. Be aware it only works in Aperture Priority (A) mode and Program (P) mode but can also set to the two Custom settings on the mode dial.

What this setting does is allow you to set the slowest shutter speed that the camera will go down to when trying to achieve correct exposure before it will begin increasing ISO. You can only use this if you set the ISO to Auto but you can decide what range the Auto ISO will operate between, with 100-400 being the lowest range.

But what I found was that once the camera has increased the ISO to the highest setting in the range you’ve set, it will go back to slowing down the shutter speed beyond the ‘Lowest Shutter Speed Setting’.

With the ISO Upper Limit set to 400 and the Lowest S/S Setting at 1/200s the camera set the Shutter Speed at 1/50s to take a picture of my Boba Fett Bobblehead.

With the ISO set manually to 400 and the Lowest S/S Setting no longer being in effect the Shutter Speed the camera chose was still 1/50s. I did the same test around my office with varying light levels and the shutter speeds always came out the same for equal ISO’s.

While you may see this as still being of some use, my view is that there’s no real gain from it. It’s simple to set ISO yourself and as illustrated in the images above it will have the same impact on what the camera will set as shutter speed as when using the Lowest S/S Setting.

The above is where I left things after my initial test in April 2023. But I’d made a substantial omission that nobody who read this blog noticed including myself. There’s a clue in the two screenshots above.

At no point had I turned on the camera flash! If I had done I would have discovered something that a friend of mine Paul ‘Duxy’ Duxfield found out recently and told me last month (March 2025). Turn on the camera flash and whatever Lowest Shutter Speed you have set becomes a hard limit. Even when the camera reaches its highest Auto ISO limit the shutter speed does not go slower than you set it to.

When using any of the TG’s even the earlier ones there has always been a limit as to what the slowest shutter speed would go down to when flash is turned on even when not using Auto ISO and setting the Lowest Shutter Speed yourself. Lot’s of other cameras do this in certain modes, it helps to ensure that the flash is the dominant lighting when using it with other light sources and reduces the likelihood of motion blur in areas where the flash does not reach. On the TG6 and TG7 that limit is 1/30s when the camera lens is at its widest and becomes faster as you zoom the lens reaching 1/100s when the lens is at its longest. This is something I noticed a while ago but I’ve not seen an explanation of why the TG’s do this. Most other cameras keep the same lower limit whatever the lens is zoomed to.

But using the TG6 or TG7 you can adjust the lower shutter speed limit to anything from 1/500s down to 1/2s and as long as you have the camera flash turned on and in any mode apart from the two Slow flash modes the shutter speed will go no slower even if the ambient light levels would normally cause the camera to choose a much slower shutter speed.

This is a massive advantage and makes it even more worthwhile opting to use flash as a light source rather than constant lighting. It’s much easier to achieve black backgrounds if you can stop the camera slowing the shutter speed down. You are less likely to get motion blur in areas that the flash hasn’t reached, if you can keep the shutter speed faster and faster shutter speed mean sharper, less noisy images.

While navigating the menus and changing the settings are somewhat longwinded to do during a dive especially in cold water with gloves it is still doable and a shortcut option would be to set one custom mode on the dial to say 1/500s for those black backgrounds and another to 1/100s for wide angle shots where you want blue or green water. Depending on ambient light and aperture setting you may still get faster shutter speeds than your lower limit but having that hard limit prevents the camera from messing things up.

Even when not using flash as a light source you could use this feature by turning on the camera flash at its lowest setting without a strobe or with the housing diffuser covered, if your housing has one. This will help you avoid motion blur in images but whenever the camera would normally take the shutter speed below the limit you’ll get images that are under exposed. Depending on how under exposed they are you may be able to fix this with software, especially if you are shooting RAW.

To conclude my advice is that if you are shooting using available light or video lights this feature doesn’t help much but for those using built-in flash or strobes that fixed minimum shutter speed is a major advantage and I wish I’d picked up on it in my original tests. I’ll certainly be using it on my future trips and recommending it to customers.

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