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Reality3D
12-24-2003, 02:04 AM
I load Cineon(10 bit per channel) files, but Info palette rgb always shows values from 0 to 255!. With levels,curve etc it's the same. How is supposed 16 bit work with photoshop?. I am avoiding something?

Ian Jones
12-24-2003, 02:14 AM
Are you using CS?

Reality3D
12-24-2003, 02:30 AM
Yes

Ian Jones
12-24-2003, 04:25 AM
k, well I don't have CS but I've been told that you goto image > mode > 16bit

Reality3D
12-24-2003, 04:57 PM
Of course, when you load a Cineon file image > mode > is at 16bit per channel by default. Any suggestions?

Ian Jones
12-25-2003, 01:46 AM
I guess thats just the way photoshop works atm. Certainly the filters are all 8-bit RGB. There are other programs which can handle floating point HDRI and high-bit imagery... search around on google.

Ian Jones
12-25-2003, 01:48 AM
Actually... I've just remembered seeing a tutorial somewhere for this. It's a fairly complicated work around but I know that there is a tute out there somewhere. I really can't remember where, but all I'm saying is that there is a way to work with them

Reality3D
12-26-2003, 02:18 AM
Well, thanks for the effort. If anyone knows something about this subject I would be very happy

EricUNSL
12-30-2003, 06:21 PM
Can someone explain to me what this 16 Bit mode refers to? What's the big deal? What is it used for? Really curious because this is the second time I've seen it mentioned.

Ian Jones
12-31-2003, 01:02 AM
16bit is just an increased colour range. The more levels you have, the more accurately you can adjust exposure and tonal details. You can see more detail in shadows, due to the increased number of levels and also more details in highlights. This allows you to adjust the exposure and retain more details. Try adjusting an 8bit image and you'll quickly notice that its very hard to bring out details in the shadows because the shadows are mostly balck and without enough details.

EricUNSL
12-31-2003, 04:20 AM
Is there a way to change an image that starts off as 8 bit to 16 bit? This is so cool I'm embarassed to not have known about it sooner.

halo
12-31-2003, 05:55 PM
yes..under the mode menu, just select 16 bit...

Of course this wont magically generate missing info, but any new info in the document will have better colour range than 8 bit.

8 bit images are 8 bits per pixel per channel, ie 256 possible tones per pixel. As RGB has 3 channels this allows 256x256x256 possible colours per pixel which is approx 16 million possible colours.

16 bit is 4096 per channel, which when cubed gives billions of colours.

Bare in mind that although this is a significant increase, its not the same as HDR images. In photoshop white is stll white, black black and there is nothing beyound the limits, the visual range is displayed entirely, where as with HDRI's the visual range isnt displayed entirely, but bracketed by exposure. 16 bit however will respond better to adjustments as the results are less likely to fall out of gamut like RGB, however the traits of destrcution some operations make will still be similar.

EricUNSL
12-31-2003, 08:22 PM
Thanks Halo,

I didn't know any of that. What I'm curious about is whether you can take a painting with multiple layers that has already been started as a 8 bit per channel image and change it to 16 bit. I tried going into modes but the 16 bit channel option is faded and unselectable. Any suggestions.

halo
12-31-2003, 09:01 PM
to be honest i dont use 16 bit that often, and CS has less restrictions as to whats available in 16 bit, but i'd look to your layers and see if your using something like adjustment layers or effects layers...there's probably something in your file that 16 bit doesnt like. If the file's suitable or by using CS you should be able to jump in and out of 16 bit.

ward
01-06-2004, 03:32 PM
Hi all,

I am just wondering if somebody knows the solution for the problem what Reality3D has mentioned. My problem is pretty much the same. I (or actually my colegue) should paint a matte painting in 16bit, but all the tools (color picker, curve, level editors) looks unusable to do the task.

I am affraid all this 16bit support was just a big hype from the Adobe. Can sy show me if I am wrong?

thanks:

Balazs

Reality3D
01-06-2004, 06:48 PM
Yes, I think this 16 bit support is only functional with the filters available(only a few), and with layers and selections in Cs. But forget to pain and edit images with 16 bit precission. Hope I am wrong :)
See these examples, one with 8 bit and the other one with 16
http://www.telefonica.net/web/r3d/8bit.jpg
http://www.telefonica.net/web/r3d/16bit.jpg

EricUNSL
01-06-2004, 10:04 PM
I really don't see any difference here. I tried working an image at 16 bit in PS 7 but it doesn't allow layers.

halo
01-06-2004, 10:46 PM
look at the lack of posterisation...notable in the chin darklight

PS CS allows almost full 16 bit functionality including layers

Jer
01-07-2004, 09:32 AM
Eric, I've run across this problem a few times before, it has to do with your layers. I forget if it only works when you have flattened image, or only when you don't have a background layer, double click the layer to name layer 0, which also unlocks it. But I'm pretty sure it's one of the 2. Haven't tried CS yet, sounds pretty sweet to me, assuming curves and hsb adjustment layers work in 16 bit, I'd be quite happy.

ward
01-07-2004, 09:45 AM
PS CS allows almost full 16 bit functionality including layers

Hi Halo,

Could you then show me how coulld I have a 16bit palette, how can I select a 16 bit color precisely, and I would be happy if you could show me, how can I switch the curves, levels, HSL, and the other similar tools to the 16 bit mode.?

thanks in adv.


Haven't tried CS yet, sounds pretty sweet to me, assuming curves and hsb adjustment layers work in 16 bit, I'd be quite happy.

that is the problem, these dont work. ok, you can adjust the values, but only in 8bit.

Reality3D
01-07-2004, 12:02 PM
Exactly. The 16 bit support only work with filters internally(so in 16 bit you don't get that posterization) and when saving again the file. But then you could pass an 8 bit image to 16 bit and apply the filter with the same result expected. ehem...

Gendou
01-13-2004, 05:11 AM
from what i understand, a 16bit image is 16bit, but for some reason Pshop still shows you the color in 8bit representation when you look in the tools/info/color palettes.. don't know why it's like this but apparently it is. the image is "supposed" to be in 16bit as long as that mode's set. of course, if you convert and8bit image to 16bit, i'm not sure if you get the increased color range or if the image has to come in to Pshop in 10bit+ channels.

correct me if i'm wrong, but i read that either in the help file or on a site (possibly planetphotoshop.com?)

-Gendou

halo
01-13-2004, 09:13 AM
photoshop displays 8 bit readings in 16 bit.

if you take an 8 bit image into 16 bit, you wont see it change in anyway, however any adjustments and filters will work and produce results in 16 bit.

ward
01-13-2004, 10:28 AM
ok, probably I was not really clear, sorry guys, I gonna try now again:

So, I know I wont have more colors if I convert an 8 bit image, and so on, but my problem is: I want to paint/select a color what is exist in 16 bit colorspace. What If I have to paint with a specific color? If the color picker is just in 8bit mode, it means I can select only 8 bit colors, right? so in spite of that I have a 16 bit image open, I cant paint onto it with 16 bit colors. (The only place where I could get 16 bit colors probably, where the brush is blending to the background.)
I have the same problem when I want to change the levels for example, I can change it in only 8 bit range, because the level editor has only 8 bit values in it and does not care about my opened 16 bit image.


So, any solutions?

thanks

Balazs

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