Jump to content
wingsy

how to whitebalance.

Recommended Posts

Hi all,I am new to underwater photogrwphy and was wondering if anyone could help me to understand whitebalancing,

 

1: how to do it on a nikon d100

2: how often do i need to do it.

3: does it have to be done for different depths.

4: would i need a magic filter to take good photos in egpyt.

 

Any help would be appreciated.

 

Cheers.

Darren.

Share this post


Link to post
Share on other sites

Hi Darren,

 

I will pick up a couple of your questions but avoid those that are D100 specific as I don't have the experience with that camera.

 

1: No bid - see above.

 

2: It is not a time related thing as in this case you are not adjusting for a camera dynamic or drift. I have stored WB settings and used them a year or more later.

 

3: Yes, if I were doing a dive and taking pictures at every level between 0 and say 18m then I would WB at 0, 6, 12 and 18 or so.

 

You don't need to carry white cards and all that fancy stuff - just use a sort of white or greyish area to set the balance - the back of your hand or sandy bottom work fine for me.

 

One issue I have had is my camera (D70 initially and now D200) rejecting the WB 'picture' - this has pretty much come down to underexposure of the WB shot.

 

4: No, but I genuinely believe that you will get better pictures with one than without. Having said that there are some inherent issues that you need to work with when you use a Magic filter.

 

Shoot RAW if at all possible - it will allow you to 'recover' shots in post that will be headed for the round bin if you shoot jpeg.

 

If you shoot RAW then the WB at the time of taking the shot is irrelevant, it is still worth doing the WB however so that you get a true picture on the back of the camera when you review.

 

The Magic filter will drop you 1-2 stops of light.

 

Try to shoot with the sun behind you and with a slight downward camera angle.

 

The filter is good to about 18m max - after that you will find that the exposure time give you a problem and that the correction that the filter provides is not ideal below this depth.

 

The Magic filter is a great tool and can be a lot of fun - conversion to B&W also works well from Magic filter shots.

 

Enjoy.

 

Paul C

Share this post


Link to post
Share on other sites

Hi Darren

 

I was using a D100 in a Subal housing for a couple of years and got some terrific results.

 

Most of the time I used it on Auto WB, shot RAW and on the rare occasion that the colours were off, tweaked it in PSE or Rawshooter. No dramas. But it was rare that I needed to do this.

 

To manual WB the D100 you have to go through the technique outlined in the handbook (I think its called Preset WB) using a slate, sandy bottom or some such as the colour reference - but obviously whilst you are underwater. As Paul explains, you need to do this every few metres because of the changing colour as you go deeper (decreasing red end of the spectrum) ; or ascend. So its not simple - although if you do it often enough its not too bad.

 

But, I'm with Paul: shoot RAW, and if Auto hasn't worked, tweak it.

 

Best wishes

Share this post


Link to post
Share on other sites

Cheers for all your advise.I will give them all a try this coming weekend.

I have a dive in a local quarry so will endeaver to try it a little.

Dont think i will be in there very long though as the temp last week was just under 8 degrees.

Share this post


Link to post
Share on other sites

Well good luck in the quarry - if your vis is anything like ours at the moment you won't see your feet.

 

Don't get disheartened in the quarry - the light levels will be very low at this time of the year in the UK and a far cry from those you will be faced with in the red sea later.

 

To be honest I would not try ambient light shots at this time of the year in the UK myself. AT least from what Tim says you can shoot RAW which is an absolute must. I would also suggest that you try jacking the ISO a couple of stops though if your Nikon is like mine then the noise gremlin will come calling after 250 / 300.

 

Let us know how you get on.

 

Paul C

Share this post


Link to post
Share on other sites

Sorry guys for bumping in. I've got a couple of related question too.

 

1) I'm using a compact P&S camera without an external strobe. I've always use the Underwater/CLoudy setting on WB instead of auto. The colour will come out more vivid. Is this the correct setting or if there's any way about it?

 

2) I was told if we are using strobe/s, we don't necesarily need to manually adjust the WB at whatever depth, just set it to auto. Is that true??

Share this post


Link to post
Share on other sites

Hi Vincent and welcome,

 

Quite a few of the P&S cameras only shoot jpeg which leaves you at the mercy of the processor in the camera, making the setting of 'mode' and WB even more critical as you will have less adjustment available later.

 

Setting 'cloudy' causes the internal processor to boost the colour saturation levels somewhat - to compensate for a 'cloudy' day which is similar to the condition that you get in the first few metres of the water column (probably on a sunny day).

 

Problem is that water is not an ND filter - it does not attenuate all of the spectrum in a linear way, you loose reds first and blues last. As you get deeper the shots tend toward being green/blue.

 

'Auto' WB goes some way - but still the internal processing in the camera is set up for air and is not expecting this much distortion of the spectrum. There is a point where the internal processor suspends belief in what it is seeing and gives up.

 

Add a strobe and you are back to a 'daylight' or similar distribution of spectrum and things start to work again.

 

Filters such as the Magic filter work by attenuating the blue while allowing much of the available red through - the response is a curve. This explains why you drop 1-2 stops using such a filter - overall it is attenuating available light .

 

This also explains one of the reasons these filters stop functioning at some point in the water column - there is a point where the available red is so low that when the remainder of the spectrum is attenuated to match there is not enough light remaining for an image. With the Magic filter on a DSLR this is at about 18-20m.

 

With the Auto Magic I understand that the cut off is a bit shallower - I have not tried one, so.....

 

The interesting thing is that you would think that shooting RAW you should be able to 'add' a Magic filter in post processing - well you can to an extent but it is not as good as the real filter - my belief is that this is due to the linear response of the CCD in the camera and the non inear human!, plus dynamic range effects of the CCD.

 

Anyhow I have got carried away with this reply, sorry about that.

 

Paul C

Share this post


Link to post
Share on other sites

Hmmm, yes, well enjoy the quarry. It's been some years since I dived in a UK quarry (Capenwray was the last) and although its was fun at the time, I don't miss it!

 

As Paul says, don't be put off if Presetting the WB doesn't work too well in that environment. Short dive times, lousy viz, shivering in a drysuit.... So handling Presets too will be a bit of a task loading-episode - and the results aren't going to be great. But you will really see the difference in the Red Sea!

 

On Vincent's question (Hi Vincent!), yeah, I must admit when using strobes I always shoot on Auto WB and will tweak if necessary on my laptop. But this usually only happens when I have been too lazy to get the strobes at precisely the right angles so the light coverage has dropped off too quickly.

 

As Paul says, if you have to shoot JPG with a P&S your options are a bit more limited. I think a few Wetpixelers have found computer-based filters that they have used to inject more reds into the pos-production when using JPGs. It might be worth a search. Better yet, trade in your P&S and sell your soul to DSLR. You know it makes sense...... :excl:

 

Stay warm in that quarry, Wingsy. Safe too!

Share this post


Link to post
Share on other sites
4: would i need a magic filter to take good photos in egpyt?

 

Hi wingsy

 

I wouldn't say that you'd need it, but I've taken better pics in the Red Sea with the Magic Filter (on my D100), especially between 5m & 20m.

 

Without doubt, adjusting the WB makes for a better pic, with a little practice it becomes a routine operation; if your D100 won't accept the back of your hand or the sandy bottom (quite often with a fisheye) try the subject matter itself, I've had excellent results from using the wrecks!

 

A has already been said, try to get the sun behind you & shoot down, also I've found re-balancing every few metres can help.

 

Good luck!

 

R

Share this post


Link to post
Share on other sites

Cheers for all the repleys.

 

I will be diving in a semi dry in the quarry as i cant get on with a dry suit and dont really feel the cold at all.

 

Just a little question,poeple keep saying adjust every couple of of metres,being new to this how do i do it.?

Sorry if i am coming across a little camera dull but it is all new to me.

 

Cheers.

Wingsy.

Share this post


Link to post
Share on other sites

Hey Wingsy

 

Brrr, makes me cold just thinking about it.

 

On the "adjusts": if you don't use strobes or Auto WB/RAW and want to use Preset WBs, you will need to go through the procedure on the D100 for "Presetting" the WB every few metres as you descend or ascend. This is because the colour of the light changes at different depths. The red end of the spectrum is absorbed as you descend. A quarry would be especially bad for this.

 

There is quite a lot to do in presetting the WB (check the D100 manual which explains exactly how you do it). It involves a number of steps. This is what I was explaining about the task-loading aspect. I'd suggest that you keep practising presetting the WB topside out of the housing first and then in the housing: until you can do it automatically. It's not something you want to learn how to do in a quarry in the UK in winter in a semi-dry!

 

Forgive me if I'm teaching you to suck eggs, but some UK quarries can be quite tricky dives. I'd suggest that you know where the bottom is (!) before you start playing with presetting. You don't want to start at 5m and discover after you've been fiddling with the camera that you have sunk down to 30m....

Share this post


Link to post
Share on other sites

Hi PRC & TimG,

 

Thanks a lot for the advise and information. And on your advise to defect to DSLR, I hold on to my camera just for the moment. I'm very new into photography. ( and I mean photography, not only UW photography). I'll just play with my existing toy for a little longer until I've garnered more experience in it before deciding my next choice of camera. Thanks anyway for your guidance.

 

Cheers.

 

p/s - good luck, wingsy.

Share this post


Link to post
Share on other sites

Glad to be of help Vincent.

 

You may have seen Paul (I think) and I plus many others suggesting in another post that a P&S is more than enough to get your teeth into if relatively new to diving and photography. You can get terrific results with a good P&S and strobe. DSLRs are just wicked underwater but very hard work to get anything decent if you don't know your way around a camera system - and, most importantly, don't have really good buoyancy skills. Once you are really comfortable with your diving and have a good idea of what you are doing with a camera, come and join us on The Dark Side with DSLRs. You'll have even more tons of fun. Mind you, your bank account will never be the same again. :) But hey, if diving wasn't an expensive enough hobby...... :D

Share this post


Link to post
Share on other sites

Sponsors

Advertisements



×
×
  • Create New...