Currently, I use a Canon Powershot S1 IS. I shoot jpeg, use a red filter (or rather color correcting filter) and custom white balance using a white slate.

I’ve now bought a Canon G9 and plan to shoot in RAW format. I don’t have a lot of experience editing RAW files, but I always read RAW format allows you to do a lot of post-processing without quality loss. Does this mean I no longer have to custom white balance underwater (would save a lot of hassle imo), or is there still some advantage to setting custom WB underwater?

Furthermore, how easy is it to correct colors in RAW without quality loss? Would my red filter also become obsolete when shooting RAW? I’ve found that the red filter makes focussing more difficult, especially in low light, since it takes some ligt away. But i has generated some nices results for me when shooting jpeg with the S1 IS. Is there an advantage in using a red filter over correcting colors in post-processing?

Hey,

The good news:  If you shoot in RAW format, there is no need to manually set white balance up while on a dive.
You will not need custom filters.
You should however have a external strobe set-up.

RAW allows you to select white balance post processing...Load up any graphics program that supports RAW and you should have some sort of selection when initially loading up the images in.

There is no bad news with RAW..oh wait....Ok files will be bigger than the jpegs your used to.  You might not be able to take as many images in quick succession…
Not too bad really.

Have fun
TANK

The good news:  If you shoot in RAW format, there is no need to manually set white balance up while on a dive.
You will not need custom filters.

Ok, that’s a pretty straightforward answer. So there’s not really an advantage to having like a reference point from Custom WB? I wasn’t sure how much work it would be to get the WB ‘right’ without a good starting point, but this sounds pretty definitive.
I guess the red filter can be sold along with the old camera then.

You should however have a external strobe set-up.

Haven’t got an external strobe yet. When needed and possible I use my dive light to light up the picture. I guess I’m spending the strobe money on dive trips at the moment…

There is no bad news with RAW..oh wait....Ok files will be bigger than the jpegs your used to.  You might not be able to take as many images in quick succession…

That’s why I bought a fast 8GB memory card as well. Guess there’s not much more I can do about that.

Thanks for the reply!

I think a reference point will be off as soon as you move away from that reference point or put more distance between that reference point. 
My simple example is:  You reference a grey card at 10 meters depth.  The card distance is 1 meter from the camera. So you use that as a white balance reference....
During the dive you take pictures at 15 meters and a distance of 5 meters and then another few more 5 meters at a distance of .5 meters.
None of the images are properly white balanced.

Using the post processing in a RAW dialogue box..you will have the option to use the auto white balance or custom white balance.  Normally I will custom white balance (with the eye dropper tool) from the particular image I am going to edit...Not a reference one I took at different distance and depth…

By the way - I take my RAW images with the setting AUTO WHITE BALANCE (AWB) on camera settings.

Hope this helps

I shoot my photo’s at “cloudy” white balance setting. Haven’t experienced any problems.

One thing is very important though, I always use a histogram to review the photo. If the photo is shot well, then both the left en the right side should be low and the middle should be high. In that way, the picture isn’t to dark/light and can be adjusted to bring colors back.

gr,

Johan

for information for anyone interested in this topic:

The OP also posted his question on wetpixel, where a huge debate ensued.  Much of the debate seemed to revolve around one person’s comments that most didn’t seem to agree with; much angst was expressed.  I have read the thread in the hope that some sort of consistent information would emerge.  Sadly, this has not been the case for me!  It was however a quite entertaining read for such an apparently ‘dry’ subject.  Here’s the link for anyone who wants to have a look for themselves.

FWIW, here’s what I have found from experience:
Shooting RAW with AWB seems to work pretty nicely for me.  I use a Iklelite D125 strobe for most shots.  Here in NZ, there’s not much ambient red light below around 15m in most conditions I encounter.  Once there’s no red, no amount of custom white balance, filters or post-processing of RAW will bring back something that wasn’t there in the first place!  (of course, if you are a good enough photoshop jockey you can create a red channel from the other channels in post processing).

If you’re shooting RAW, I’m not convinced that the white balance setting you choose does anything more than add a reference point to the image data.  Your actual image information is unchanged.  When you process the RAW file, your software can read the white balance reference and use it, or you can use a custom setting.  The Custom setting can usually be set either by an ‘eye dropper’ type tool that allows you to select something that should be white/grey in the image, or by manually setting a colour temperature.

regards

Hi
Started to use the G9 one month ago in the Maledives.
I selected the setting RAW+Jpeg, used a 2GB card. This capacity proofed sufficient for plenty of pictures for three dives.
In the evening I downloaded the data onto my laptop.

Install the Canon software delivered with your G9. The “Camera Window\” will allow the downloading from the camera. In the “Image Browser” Menu “File” ==> “Processing RAW Image” will start the RAW Image task. This is where you can modify the white balance as you want. The RAW Image task will allow to save the picture data as .tiff format which you may use for further processing in Photoshop for example.

Cheers
Alex