# question about Post work



## lorigon27 (Sep 4, 2012)

i recently watched a video with arthur st. john and thought his work is amazing--
my question is--  how does he get the tones in the sky to look this awsome?  
heres the link to the youtube video    Fashion Photo Shoot on the Beach with Tawnie Lynn - YouTube

as much detailed info would be sweet        thx in advance


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## leeroix (Sep 4, 2012)

looks like they are waaaaaay over saturated. so she must have been masked out and then the background altered.


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## Big Mike (Sep 4, 2012)

Firstly, to get dark tones in the sky like that, you start by underexposing it.  So he's simply using the exposure settings on his camera, to underexpose the ambient light/scene/background.  But also notice that he's using a flash/strobe.  The strobe lights up the model, but obviously not the sky, so in the resulting photo, the sky is dark and the model is well lit.  The key is to realize that every flash photo is actually two exposures...one for the ambient, one for the flash.  If you know what you're doing, it's fairly easy to get the balance/ratio that you want.  

Secondly, he might be using a polarizing filter.  Such a filter, when pointed at the blue sky, while perpendicular to the sun's rays, can give the sky a significantly darker blue color.  I think he's using one, because in the photos, you can see quite a gradient in the blue of the sky...which is the result you get with a wide angle lens and a polarizer.

Lastly, it doesn't take much in terms of post processing, to pump up the saturation and lower the tone of the sky.


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## lorigon27 (Sep 4, 2012)

thanks alot--im familiar with ocf but those skies were just awsome to me and was under the assumption he was doin something i wasnt aware of.
im gonna have to get a polarizer for my wide lens i guess


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## TCampbell (Sep 5, 2012)

He may be adding an ND filter to the mix just to help with the exposure.  

If you're using a flash, you can't exceed the 1/200th flash-sync speed of the shutter (well... you can with a flash that supports high-speed sync but that's a different topic.)  When you introduce a radio, it may add *just* enough delay to create a fuzzy edge on the photo as the shutter starts to move before the light was full -- so you drop the shutter to 1/160th to correct for that.  The problem now, is that under sunny-16 conditions, you're at ISO 100, f/16, and 1/100th.  You're always down to the slowest ISO, you're nearly at the last f-stop on the lens, and you only have 2/3rds of a stop up to 1/160th with shutter speed and that's not enough.  

A polarizer will cut the light, but polarizers can be variable (usually up to 2 stops, but you can't necessarily count on that because it depends on the angle of the dominant light and how you've tuned the polarizer... it could be as little as 2/3rds of one stop.)  

By adding an ND filter, you can control the light to drop the backdrop exposure and use the flash to boost the foreground.  The ND filter changes your shooting conditions and allows you to use exposure settings outside the range of what's available without the filter.


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## Big Mike (Sep 5, 2012)

Yes, the key to really pulling this off, is having enough flash power and being able to limit the ambient exposure.
As Tim mentioned,  you'll likely be limited to a shutter speed of 1/200 or 1/250, so the only way to keep your skies dark is to use a low ISO, a really small aperture and/or ND filters.  And those will all limit your flash exposure as well...so you'd need to keep turning up the flash power.  A hot-shoe (on or off camera) flash would struggle with that, which is why he's using a portable studio style strobe.


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