Finally pulled the trigger on my upgrade to the Canon S100

[Interceptor121]

The ND filter puts it down 3 stops so yes they would come dark

The exposure compensation on the camera does nothing, the flash ev compensation does something...

 

[Foxfish]

Which exposure setting?

See above. I think having the ND filter on was the problem.

In the menu settings, the flash mode was set to auto.

Shutter synch was set to second curtain. I think this means there is a time gap between the pre-flash and the main flash. Can you confirm this is the case. Either way the strobe switch position is the same when in manual mode.

---------- Post Merged at 11:38 AM ---------- Previous Post was at 11:30 AM ----------

The ND filter puts it down 3 stops so yes they would come dark

The exposure compensation on the camera does nothing, the flash ev compensation does something...

Thanks for that. You posted before my last post.

Not sure what you mean by camera compensation.

 

[Interceptor121]

Shutter sync has to be set on first curtain

Second curtain sync is only used on long exposure shots to achieve special effect

Essentially on first curtain the flash fires immediately, with second curtain it fires towards the closure of the shutter

 

[Foxfish]

Shutter sync has to be set on first curtain

Second curtain sync is only used on long exposure shots to achieve special effect

Essentially on first curtain the flash fires immediately, with second curtain it fires towards the closure of the shutter

Okay, thankyou. Another thing you may be able to clarify. I think the S100 has a preflash. If so, does the strobe fire a preflash when the camera preflash fires?

 

[Interceptor121]

I understand you have a YS-01?
The strobe has 3 modes
1. Preflash
2. No preflash
3. TTL
The no pre flash mode has to be used when you set the camera's flash to manual

The correct setting allows the YS01 to fire at the real flash fire not at the pre-flash

At pre flash the YS01 does nothing

 

[Foxfish]

Right. The strobe is a YS-01. So what does the camera use to set flash intensity given that the camera preflash is masked when using a strobe and there is no strobe preflash? And what sets the strobe intensity in DS TTL mode?

 

[Interceptor121]

We are now going into super technical matters and Sea and Sea does not actually documents how they do it
My understanding is that the pre-flash sets the initial intensity of the internal camera flash, as this is masked it will set it to FULL power the internal flash, the strobe itself in TTL shoots in full power
The camera then takes the picture and fires the external strobe that is now beaming full power, when the camera detects that there is sufficient light it stops the internal flash, the Sea and Sea read that the internal flash has stopped and stops the strobe as a consequence
So in my understanding the strobe does not preflash, I might be however wrong but the above deduction seems consistent with the behavior of the strobe

 

[Foxfish]

We are now going into super technical matters and Sea and Sea does not actually documents how they do it
My understanding is that the pre-flash sets the initial intensity of the internal camera flash, as this is masked it will set it to FULL power the internal flash, the strobe itself in TTL shoots in full power
The camera then takes the picture and fires the external strobe that is now beaming full power, when the camera detects that there is sufficient light it stops the internal flash, the Sea and Sea read that the internal flash has stopped and stops the strobe as a consequence
So in my understanding the strobe does not preflash, I might be however wrong but the above deduction seems consistent with the behavior of the strobe

So you suggest that the camera flash intensity will always fire at maximum level and the strobe is synchronised to start and stop with the camera flash. Sounds sensible.

I read somewhere that the strobe ignores or cancels the preflash from the camera.

 

[Interceptor121]

Yes that is what I think DS-TTL does

This explains why some people have issues with the DS-TTL which explains why sometimes you need flash exposure compensation to make it work, especially with clear housings

In fact when I see the DS-TTL II on the YS-DS1 it says it does pre-flash and has a proper Ev controller

 

[Foxfish]

Having used the camera a few times now, can comment further as follows:

Had no problems with 'slippage' using the front ring to adjust the zoom at depth.

Have had some difficulty adjusting the exposure value using the back ring. If you press just that tiny bit too hard you end up cancelling the EV menu and changing the shutter speed in Tv mode.

I'd be interested to hear how people adjust settings for normal shooting. I'm using Tv mode. ISO and white balance are set to run on auto. If I adjust the focus the aperture automatically closes. I presume this is because the depth of field becomes more of a problem with a narrower field of view.

I've now got the strobe working well in TTL and am generally happy with the result, though there is some fine tuning to be done. Last dive I had trouble with the photos being underexposed. This time some of the photos were over exposed. I'll need to wind back the EV or adjust the shutter speed up. I'd be interested to hear other methods.

---------- Post Merged at 08:29 AM ---------- Previous Post was at 08:11 AM ----------

A couple of photos





Okay, they are a bit ordinary but the visibility was not the best after 3-m swell during the week. The shots were taken at 20m and 15 m. With the second shot I couldn't get any closer without spooking the fish so should have used the zoom.

There is some blurring so the shutter speed could have been faster.

Here is another of some reef and coral. Light from the sun on the right side has overexposed the shot. This occurred on a number of the photos I took. Would be interested to hear how you get around this.



Any other advise apart from 'give up while you're in front' would be welcome.