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16bit anyone?

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Anvh
Posted 16/05/2009 - 22:07 Link
All the newer Pentax models have 14bit RAW files, since that isn't a standard setting I'm wondering in what bit-depth your working space is, 8bit or 16bit.

I must confessed that I'm only recently using photoshop in a 16bit working space, it just didn't come in mind to work in higher bit depth but I can see the advantage in working in them.
- 8bit only has 256 colours,
- 14bit the one the camera captured has 16384 colours, so it seems to me you're loosing a lot of colours when converting to 8bit
- 16bit has 65536 colours so that's enough to contain all the colours in the RAW file.

I'm no computer expert so am I on the right track or not?
Stefan
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K10D, K5
DA* 16-50, DA* 50-135, D-FA 100 Macro, DA 40 Ltd, DA 18-55
AF-540FGZ
Mannesty
Posted 16/05/2009 - 22:19 Link
16 bit would seem to be the best to work in but you'll find that most of the filters are greyed out because they work only in 8 bit mode. For that reason I stick with 8 bit.
Peter E Smith - flickr Photostream
Anvh
Posted 16/05/2009 - 22:37 Link
Luckely not the ones I'm using and I believe that only the creative filters are greyed out.
All the ones I can think of for polishing up your photo are still there.
- All the noise, blur and sharpen options are there except smart blur.
- lens correction under distort
- emboss, find edges, solarize filters under stylize.
- All the filters under other.
- all layer options.
- all adjusment layers and layer/image adjusments (curves, levels, sturation, etc.)
- all tool works (smudge, dodge, clone, fill, etc.)
- and I'm lucky enough that the noise removal software support 16bit.
I can't say I miss something maybe you do though?
Stefan
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K10D, K5
DA* 16-50, DA* 50-135, D-FA 100 Macro, DA 40 Ltd, DA 18-55
AF-540FGZ
Anvh
Posted 16/05/2009 - 23:06 Link
piotro wrote:
Most of the cheap LCd monitors are not going to display anything better that 8 bit anyway .

mhmm you're right there, I'm working on a CRT though.
But still for 8bit monitors you will end up with a more accurate photo when working in 16bit. If one 16bit colour is on the border of a 8bit colour it might wel end up after processing as another colour were the colour might still be the same when the photo was converted in 8bit first.

Good it's on the border of usefullness but if you can why not do it?
Everyone is using TIFF for not loosing any image quality but I'm quite sure that most of them are 8bit so you throw away 16128 colours, that seems to me far less usefull... I'm not going anal right now right
Stefan
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K10D, K5
DA* 16-50, DA* 50-135, D-FA 100 Macro, DA 40 Ltd, DA 18-55
AF-540FGZ
beakynet
Posted 16/05/2009 - 23:28 Link
Stefan,

You are right that 8 bits equates to 256 colours, however the 8 bit refer to 8 bits per channel (Red, Green, Blue - RGB) which gives 256*256*256 colours. However, this is further complicated by the colour space you are working in (Adobe or RGB)

16 bit allows to to represent many more shades of colours, however printers still only work in 8 bit colour space!

So, if you are doing lots of editing, use 16 bits to retain shades during editing and thus retain best quality, however you will always be printing at 8 bits.
Bodies: K5IIs, K7, MZ5n, LX, MV
Lenses: DA*16-50, DA18-55WR, DA18-135, DAL35, M50 F2, A50 f1.4, FA50 f1.4, DA*50-135, DA55-300, Tamron 70-300, DFA 100 WR Macro, M135 f3.5, Sigma 120-400 APO DG HSM, Tokina 500 f8.0
Flash: Metz 58, Metz 48
Accessories: BG4, Pentax right angle finder, Pentax mirror adaptor lens, O-ME53 Viewfinder Loupe
Auto 110 System: Auto 110, Winder, 18mm, 24mm, 50mm, 70mm, 20-40mm, AF100P, 1.7x telecon
piotro
Posted 16/05/2009 - 23:32 Link
Anvh wrote:
piotro wrote:
Most of the cheap LCd monitors are not going to display anything better that 8 bit anyway .

But still for 8bit monitors you will end up with a more accurate photo when working in 16bit.

Yes, but you will not be able to see it on a poor monitor .
Doing bigger prints may benefit (no/less signs of colour banding in final image due to 16 bit operations).
What is worse, quite a lot of LCD monitors that use TN pannels (beside the fact that TN is completely useless for colour work) are using 6 bit LUT for intenal gamma correction. So people try to "calibrate" them - what on these TN pannels is quite random anyway, and get nasty banding constrained by the 6 (sometimes 8 ) bit monitor's LUT.
Edited by piotro: 16/05/2009 - 23:34
isdky
Posted 16/05/2009 - 23:35 Link
When working with 8bit images, we are referring to 8bits per channel, so you have 256 shades of each red/blue/green colour - mixing these varying shades gives you a palette of 16,777,216 possible colours.

So, when working with 16bit images we have 65,536 shades of each red/blue/green colour giving a staggering 281 trillion possible colours - the human eye cant see the difference between an 8bit and a 16bit image.

However, when doing alot of editing on the image in photoshop, the image can become degraded - the most common is banding, where colour transitions become stepped.

Its always better to work in 16bit for as long as you can, once your happy with the image or need to use an 8bit filter, then change - your images will suffer alot less artifacting and banding working this way.
"Real stupidity beats artificial intelligence every time." Terry Pratchett

Flickr Photostream
Anvh
Posted 16/05/2009 - 23:43 Link
Beakynet, you make my head spin now

Yes under PS it says 8bit/channel but a 8bit colour space means something else right. it means that the the whole colour space is build up out of 8bit and not just one channel?
So does Pentax RAW have 14bit colour space or 14bit/channel?
Stefan
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K10D, K5
DA* 16-50, DA* 50-135, D-FA 100 Macro, DA 40 Ltd, DA 18-55
AF-540FGZ
beakynet
Posted 16/05/2009 - 23:43 Link
isdky wrote:


However, when doing alot of editing on the image in photoshop, the image can become degraded - the most common is banding, where colour transitions become stepped.


The degrading effect is significantly reduced by using layers. Also, 16 bits requires more memory to process - suddenly 1GB RAM won't cut it!
Bodies: K5IIs, K7, MZ5n, LX, MV
Lenses: DA*16-50, DA18-55WR, DA18-135, DAL35, M50 F2, A50 f1.4, FA50 f1.4, DA*50-135, DA55-300, Tamron 70-300, DFA 100 WR Macro, M135 f3.5, Sigma 120-400 APO DG HSM, Tokina 500 f8.0
Flash: Metz 58, Metz 48
Accessories: BG4, Pentax right angle finder, Pentax mirror adaptor lens, O-ME53 Viewfinder Loupe
Auto 110 System: Auto 110, Winder, 18mm, 24mm, 50mm, 70mm, 20-40mm, AF100P, 1.7x telecon
Edited by beakynet: 16/05/2009 - 23:43
beakynet
Posted 16/05/2009 - 23:45 Link
Anvh wrote:
Beakynet, you make my head spin now

Yes under PS it says 8bit/channel but a 8bit colour space means something else right. it means that the the whole colour space is build up out of 8bit and not just one channel?
So does Pentax RAW have 14bit colour space or 14bit/channel?

Yes on the 14 bits, but no on the 8 bits! It is a bit like the quoted 230,000 dots on the K20D LCD! as each pixel is made up of 3 (8bit) dots, this gives an LCD with 76,667 pixls!

However, this is derived from a 22bit AD converter on the chip in the K10D! Head spinning any more now?
Bodies: K5IIs, K7, MZ5n, LX, MV
Lenses: DA*16-50, DA18-55WR, DA18-135, DAL35, M50 F2, A50 f1.4, FA50 f1.4, DA*50-135, DA55-300, Tamron 70-300, DFA 100 WR Macro, M135 f3.5, Sigma 120-400 APO DG HSM, Tokina 500 f8.0
Flash: Metz 58, Metz 48
Accessories: BG4, Pentax right angle finder, Pentax mirror adaptor lens, O-ME53 Viewfinder Loupe
Auto 110 System: Auto 110, Winder, 18mm, 24mm, 50mm, 70mm, 20-40mm, AF100P, 1.7x telecon
Edited by beakynet: 16/05/2009 - 23:48
Anvh
Posted 16/05/2009 - 23:47 Link
Ah thank you all for making things clear, good I asked the question

I had the same thoughts as isdky but it isn't as worse as I thought it was
Stefan
Comment Image

K10D, K5
DA* 16-50, DA* 50-135, D-FA 100 Macro, DA 40 Ltd, DA 18-55
AF-540FGZ
Anvh
Posted 16/05/2009 - 23:48 Link
beakynet wrote:
Anvh wrote:
Beakynet, you make my head spin now

Yes under PS it says 8bit/channel but a 8bit colour space means something else right. it means that the the whole colour space is build up out of 8bit and not just one channel?
So does Pentax RAW have 14bit colour space or 14bit/channel?

Yes!

However, this is derived from a 22bit AD converter on the chip in the K10D! Head spinning any more now?

yep....
and what do you mean yes... yes 14bit/channel or yes 14bit colour space...
14bit/channel right?
Stefan
Comment Image

K10D, K5
DA* 16-50, DA* 50-135, D-FA 100 Macro, DA 40 Ltd, DA 18-55
AF-540FGZ
Edited by Anvh: 16/05/2009 - 23:49
isdky
Posted 16/05/2009 - 23:49 Link
Quote:
The degrading effect is significantly reduced by using layers. Also, 16 bits requires more memory to process - suddenly 1GB RAM won't cut it!

Multiple layers also require more memory to process, for photoshop work, 1gb of RAM hasn't cut it for several years!!!

Personally, I'd rather have the flexibility of 16bit while editing than have to be careful having to use additional uneeded layers...
"Real stupidity beats artificial intelligence every time." Terry Pratchett

Flickr Photostream
iceblinker
Posted 17/05/2009 - 00:11 Link
I mostly process exclusively with Silkypix, with which the question is irrelevant. But I make a 16 bit TIFF if I'm going to use another program that will handle it.
~Pete
Edited by iceblinker: 17/05/2009 - 00:12
piotro
Posted 17/05/2009 - 00:17 Link
Anvh wrote:
So does Pentax RAW have 14bit colour space or 14bit/channel?

beakynet wrote:
Yes on the 14 bits, but no on the 8 bits! However, this is derived from a 22bit AD converter on the chip in the K10D!

(aside) If I remember correctly K10D actually saves RAWs in 12bits, not sure about K20D. Not sure also how it converts longer data to a 12/14 bits (simple truncate or something else).
Edited by piotro: 17/05/2009 - 00:18

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