# Postprocessing brush instead of cto/ctb gel?



## Marsu42 (Sep 19, 2014)

Good photogs will probably cringe at the mere though, but I dare to ask anyway :-o ...

... my enthusiasm for "correct" flash gelling has recently diminished a bit because for many scenes with defined edges or surfaces, correcting the white balance (temperature, tint) with the postprocessing tools in Lightroom work just fine. Plus often I need to tweak the local wb _anyway_ since 1/4 or 1/2 cto doesn't necessarily hit the correct spot, and even "real" shadows are often too blue, so why bother at all with gels?

Am I missing something here, is postprocessing wb different than flash gelling? As far as I see it, the flash blocks some up some light frequencies and taking away these from the raw file should amount to the same thing?

Note that this only applies if you can quickly smudge over whole areas with a corrected wb, for fine foreground/background details gelling the flash is the work-saving way to go.


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## privatebydesign (Sep 19, 2014)

Marsu42 said:


> Good photogs will probably cringe at the mere though, but I dare to ask anyway :-o ...
> 
> ... my enthusiasm for "correct" flash gelling has recently diminished a bit because for many scenes with defined edges or surfaces, correcting the white balance (temperature, tint) with the postprocessing tools in Lightroom work just fine. Plus often I need to tweak the local wb _anyway_ since 1/4 or 1/2 cto doesn't necessarily hit the correct spot, and even "real" shadows are often too blue, so why bother at all with gels?
> 
> ...



You are not missing anything, I gel but often in very mixed light source venues it is impossible to get everything "right" without going to extremes like gelling windows etc. Nowadays it is easier, quicker and cheaper to use the WB in the brush tool on LR.


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## Besisika (Sep 23, 2014)

Perfect photographer would tell you that you should have everything right in camera.
I am not a big believer of that theory. Any photo I intend to keep must go through post processing, even just for the sake of sharpening.
And yet, I gel. I find it easier to fix gelled strobe. 
I don't use lightroom, I use ACR and the new filter in PS CC makes it even easier but I still gel. Can't explain the theory behind it, just take my answer as a statistic in nature.


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## Coldhands (Sep 25, 2014)

I seem to recall reading that adjusting WB involves selectively amplifying the different colour channels (RGB), so theoretically moving away from ~5500K could introduce extra noise. However with a gelled flash, one could just add another 1/3 to 1/2 stop of power to overcome the light loss (assuming you're not already at max output).

Now, whether this actually makes _any_ appreciable difference...


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## privatebydesign (Sep 25, 2014)

Besisika said:


> Perfect photographer would tell you that you should have everything right in camera.
> I am not a big believer of that theory. Any photo I intend to keep must go through post processing, even just for the sake of sharpening.
> And yet, I gel. I find it easier to fix gelled strobe.
> I don't use lightroom, I use ACR and the new filter in PS CC makes it even easier but I still gel. Can't explain the theory behind it, just take my answer as a statistic in nature.



What new filter in PS CC?


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## AcutancePhotography (Sep 25, 2014)

Bottom line: Does your process give you the images you like? If so, stick with it. If not, change it.

Really only you can decide whether the final image is to your liking.


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## privatebydesign (Sep 25, 2014)

AcutancePhotography said:


> Bottom line: Does your process give you the images you like? If so, stick with it. If not, change it.
> 
> Really only you can decide whether the final image is to your liking.



Unless it is commercial work and then the only opinion worth anything is the clients. When time/money become a factor then "the best" or most correct way of doing something doesn't necessarily make the most financial sense.


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## mackguyver (Sep 25, 2014)

I'll gel my lights if I'm shooting an interior with a dominant light source (or sources) that are all the same color temp, especially fluorescent lighting with it's crappy CRI that often needs fill. For mixed lighting, I'll generally just take reference shots of a white card to make white balancing easier in post. If it's mixed lighting (that I can't gel or control) and I'm shooting from a stationary spot and it's critical (read: paid) work, I'll set the custom WB with a white card to get things as close as possible from the start.

The only issue I ever have with WB in post is that I don't always have a reliably neutral spot to use the WB dropper on - which is why I always try to take a white card reference shot.


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## Marsu42 (Sep 25, 2014)

mackguyver said:


> The only issue I ever have with WB in post is that I don't always have a reliably neutral spot to use the WB dropper on - which is why I always try to take a white card reference shot.



For reference: My standard issues with wb are outdoor shots near dawn or sunset when the natural wb changes quickly and you're very unlikely to hit the correct spot with a gel. I've got a fancy x-rite white card with automatic dng profiling for indoor shots, but as everybody except me probably knew all along this isn't working at all outdoors. That's why I found out that wb-brushing color casts is very effective vs. gel hassle. Bets are off for other shot types like the described indoor commercial work with mixed lighting.


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## privatebydesign (Sep 25, 2014)

Marsu42 said:


> mackguyver said:
> 
> 
> > The only issue I ever have with WB in post is that I don't always have a reliably neutral spot to use the WB dropper on - which is why I always try to take a white card reference shot.
> ...



Ditto. Here is a dawn shoot with dramatic DR (don't tell anybody though as this isn't a DR thread!) and colour balance issues. It was already a 4:30 start so getting there even earlier to gel the tungstens to blue would be expensive and as the rising sunlight changes so fast impractical.

I'm not advocating not using gels, but sometimes it is easier and cheaper to deal with in post.


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## ejenner (Sep 26, 2014)

Man I wish I'd started using gels earlier. So many hours wasted in PP, but at least I have that experience if I need it and it also taught me what I can and can't fix. (I only shot B&W film).

But like with everything I don't think there is 'one answer' and it comes down to being experienced enough to know when PP will be easier/better and when using a gel will be.

For the half indoor/outdoor shot above I would not use a gel.


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