# setting up photoshop for 16bit?



## Trbo323

so the other day i noticed my files are coming into my computer in 16bit but my output psd files are 8bit. how do i set up PS to use 16bit the whole way through?


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## KmH

That is called bit-depth. It will depend what version of Photoshop you have, which you don't mention. PsE is pretty much limited to an 8-bit depth and many of the tools/filters/functions in PS CS can only be used in 8-bit mode.

If you have Psw CS click on Image > Mode> and selelct 16 bits/channel in the drop down box.

Have your keyboard checked out. It appears your shift key is not working. Most TPF members make the needed capital letters and proper punctuation.


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## Trbo323

Awesome, found it thank you


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## Garbz

One thing to mention is that if you need to actually select 16bit mode, then the image wasn't opened in 16bit to begin with. If this is the case look through the CameraRAW plugin window. It'll give you the option of what bitdepth to open the image. file then you'll need to 

Also once is 16bit always in 16bit. If you want to save the image as a JPEG or another 8bit format don't use the same method to convert back to 8bit. Either flatten all layers first before the conversion, or use the "Save for Web and Devices" dialog to save the file or you'll end up undoing all the hard work.


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## Trbo323

for anything im seriously working on i use PSD format, i shoot in raw and only save separate files to JPEG when needing to give digital copies to friends or my models 

so when saving as a JPEG it goes into a 8-bit format is what your saying?


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## Garbz

JPEG is an 8bit format. There's no avoiding that. 

More to my point was the fact that Photoshop will undo all you lovely 16bit work IF you convert to 8bit BEFORE flatting all the layers in the image, and by that I mean all processing is reverted to 8bit on all layers, and since calculations are not fixed or final between layers what you end up with is an image no better than if you were to work in 8bit from the beginning. So when saving a JPEG use the "save for web and devices" dialog as anything done within this dialog will not affect the image you're working on in photoshop.


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## Trbo323

but if i already have a flattened image in PS then why does it matter which dialog I use? its going to convert it to 8 bit no matter what right?

i must be missing something here


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## Garbz

On a flat image it makes no difference. What you see on the screen is what you get. There's no calculations going on to display the final image, and it's just showing the layers. 

However on an image with layers, what you see on the screen is the mathematical result of all of the layers you have on the image. If you process this image in 16bit, and then convert to 8bit, all those calculations done to display your final image revert to 8bit. 

If you flatten the image in 16bit, the calculations are done one final time in 16bit and your conversion to 8bit doesn't have any effect since all visible colours in the sRGB gamut can be represented in 8bits. 

The Save For Web and Devices dialogue has the same effect. It still processes all layers in 16bit and then downconverts the final result.



Ooooh forgot to mention this only affects Photoshop CS4 and earlier. Photoshop CS5 will allow you to select JPEG even if the current image mode is 16bit, CS4 will require the current image mode to be 8bit before you get the option to save.


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## Trbo323

ok so let me see if i have this right, if i have my layered image in 16bit then flatten it in 16, then save as jpeg it is preserving more info right? i could also with my layered 16bit image use the save for web dialog (which kinda confused me when i tried the other day) option which basically does the same thing and preserves the info?

but what i dont want to do is save my layered 16bit image as a jpeg without flattening it?


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## Joseph Westrupp

Trbo323 said:


> but what i dont want to do is save my layered 16bit image as a jpeg without flattening it?


If you're using CS5, there's no issue, because you can save straight to JPEG from 16 bit. If you're using CS4 or earlier, flatten in 16 bit first, then convert to 8 bit, then save.


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## Garbz

Trbo323 said:


> but what i dont want to do is save my layered 16bit image as a jpeg without flattening it?


 


Joseph Westrupp said:


> If you're using CS5, there's no issue, because you can save straight to JPEG from 16 bit.


 
And that's exactly the problem. If your using CS4 or earlier you won't be given the option to save as a JPEG unless your working in 8bit, and if you convert to 8bit before flattening you've toasted the image.


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## GooniesNeverSayDie11

Also, its worth mentioning, that many filters will be unavailable in 16bit mode depending on your version.


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## cidrmakr

When the raw file is demosaiced in acr, the options (the link at the bottom in acr) sets whether 8 bit or 16 bit, which color space, and resolution.  After adjustments in acr you then open in ps so it ends up whatever you set acr for.  16 bit has a lot of advantages, particularly if you also set color mode for prophoto, in that you can do a lot of adjustments and still not end up with a spiked histogram.  When at a point that you need the filters that won't work in 16 bit, if you are using prophoto you need to convert the color mode to adobe98 first then convert to 8 bit.  If you have a super shot master file that you want to save just save it first, duplicate it, rename, and do the conversions on it.  When all done just flatten and save as a jpg.  The ONLY TIME you ever want to us "save for web and devices" is if you are actually going to make an image for facebook, etc.; otherwise always use "save as" instead.  Big difference in print quality. Of course, if you need both forms of jpg then you need to duplicate again OR use the export panel in bridge to make a small one.


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## Garbz

cidrmakr said:


> if you are using prophoto you need to convert the color mode to adobe98 first then convert to 8 bit.


 
Only if you want just slightly less banding than you would if you just had left it. AdobeRGB's gamut has more possible colour combinations than can be expressed in 8bit. The only time you should convert to 8bit is if your image is sRGB. 

Mind you for 99% of the people out there this doesn't matter. You only get advantages of wider gamuts if you use a medium which can display the wider gamuts. The internet is not one of those mediums. For expensive prints yes, use wide gamuts, also use high bitdepths, and if you intend to do exactly as you did then I would go over my final image with a fine tooth comb before hitting the save button. Depending on your image it may or may not matter.


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## Joseph Westrupp

Garbz said:


> cidrmakr said:
> 
> 
> 
> if you are using prophoto you need to convert the color mode to adobe98 first then convert to 8 bit.
> 
> 
> 
> 
> Only if you want just slightly less banding than you would if you just had left it. AdobeRGB's gamut has more possible colour combinations than can be expressed in 8bit. The only time you should convert to 8bit is if your image is sRGB.
> 
> Mind you for 99% of the people out there this doesn't matter. You only get advantages of wider gamuts if you use a medium which can display the wider gamuts. The internet is not one of those mediums. For expensive prints yes, use wide gamuts, also use high bitdepths, and if you intend to do exactly as you did then I would go over my final image with a fine tooth comb before hitting the save button. Depending on your image it may or may not matter.
Click to expand...

So converting to 8 bit while still in Adobe RGB could actually be detrimental to the final image?


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## PASM

Just to mention too..JPEGs are 24bit color (8 bits per channel)


GooniesNeverSayDie11 said:


> Also, its worth mentioning, that many filters will be unavailable in 16bit mode depending on your version.


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## cidrmakr

Keep in mind that 99% of monitors can ONLY show srgb.  Whether you have adobe98 or prophoto or lab as the color mode, what you see is srgb.  If you soft proof properly with the final you can see differences in out of gamut between the various color spaces but you have to be set up to soft proof properly.  Also keep in mind that what you are seeing is the composite of three channels (open channels and look at it in ps).  When you convert color spaces the software simply changes the values of black and white in each of the three channels.  Same when you go from 16 bit to 8 bit.  The numbers just get crunched.  Problem is that once crunched there will be blank spaces if you try to go back, so you cannot go back.  Try to go from 8 bit to 16 and ps will do it by creating / guessing numbers to fill in the holes.  Same with srgb to adobe98 or adobe98 to prophoto.  ps just guesses where to fill in.  When done with a print it will be saved as a jpg, in 8 bit, and sent to a printer in the color mode they want - either adobe98 or srgb.  The only reason for going thru all the hassle of 16 bit and converting color modes is to reduce or eliminate damage to the image that shows up as banding, artifacts, outlines, and lots of other not so good things - if an only if you are printing 16x20, 24x30 or bigger as I do (my prints will be at ArtExpo, NY).  If you are only making 8x10's it don't matter one way or the other and you will never see a difference between 8 or 16 or color modes.  Especially if you are not into heavy modification of the image.


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## Garbz

cidrmakr said:


> Try to go from 8 bit to 16 and ps will do it by creating / guessing numbers to fill in the holes.  Same with srgb to adobe98 or adobe98 to prophoto.  ps just guesses where to fill in.



This part is a bit wrong. There's no creating or guessing going on. It's a straight conversion. There will be holes. If you have pixels with the values 0, 1, 2, 3 then they would take the values as 0, 256, 512, 768, 1024 respectively.


That said and slightly off topic, there's still a benefit of converting an 8bit image to 16bit for the purposes of editing. This is because photoshop will work with layers in the order they are presented, in the bitdepth that it's set at. So if you have an 8bit image, and you apply a curve to make it look very dark, and then another curve to bring it back to light you'll get much worse banding if you're in 8bit, than 16bit, even if the original image opened only contained 8bits of data.


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## Trbo323

thanks for all the info guys, it really helps, while right now most of my stuff is displayed in a digital format as my schooling goes on more and more will be printed. the bad news is the photo department here still uses CS4 and wont upgrade untill CS6 comes out. I have CS4 on my system and have been debating going to CS5 since i can get it for $150 but im not sure if there will be any issues when learning one thing in class on CS4 then coming to my computer and trying to do it in CS5

thoughts on that?


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## Garbz

My suggestion is stick with CS4. It's quite capable, and everytime Adobe releases a new version of Photoshop they depreciate support for older versions of Adobe CameraRAW. Meaning if you buy CS5 now, and CS6 comes out, and you THEN buy a new camera you may not be able to process RAWs and have to shell out yet again for a forced upgrade or jump through hoops to get your RAW files in. 

Ultimately though there are a few cool features on CS5. Content Aware Fill, Focus Stacking, GPU acceleration that may make it worth the upgrade. Depends if you think this is worth $150.


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