[Xastoul]

Hi all,



I would like to see, the difference between the file compression.

The reason is that my camera is only able to do 12 bit. Sometime I have some problems with color transition, specialy in brigth blue sky. When I reajust the color in my raw editor, somtime I end up with a realy harsh transition, like if the color tone range was not big enough.



The D7000 have 3 setting, Losseless, 14 bit and 12 bit. So I was wandering if somebody with a D7000 would be kind enough to take the same picture ( including a bright blue sky) with those 3 different setting so I could play with it and see the difference.



Regards,



Frank

[wim]

Hi Frank,



Why would you do this in your RAW editor? This is typically something one would do on a 16-bit processed file, a .tif or .psd, from a processed RAW.

Other than that, a bright blue sky which is fairly evenly lit may actually have very few steps going from bright blue to even brighter blue, and pulling those steps apart will make those steps show up as banding. At most, adjust the curve in RAW a little, and sharpen a little and/or add a little contrast just to undo the effect of the AA-filter, and that is really it. Save to a 16-bit file to work on.



There are two things one can do to avoid this as much as possible, or 3 if you are prepared to shoot HDR:



1) Shoot HDR

2) Underexpose the sky (a) if that is an important part of the picture, or use (strong) ND grads (<img src='http://forum.photozone.de/public/style_emoticons/<#EMO_DIR#>/cool.gif' class='bbc_emoticon' alt='B)' /> or even both

3) Always work on 16-bit files until you are completely done with processing including resizing. Only when finished convert to 8-bit jpegs or similar



1) and 2) are optional, 1) sometimes is impossible, and 2), especially (a) potentially adds noise at the lower end of the tonal scale. 3) is a must.



Other than this, personally I would always shoot lossless. Any of the other two options imply that something is lost in the recording, and that which is not recorded, cannot be retrieved at a later time.



HTH, kind regards, Wim

[Xastoul]

Hi Wim,



Let me descript my "normal" way to process a picture nad maybe you can tell me what's wrong.... ( there may be a lot since I would describe myself as between a maybe good noice and a crappy amateur...)





1) Maye raw editor was a bad wording, I using Bibble 5 wich is acttually a raw converter.



2) In that particular piscture, there was a dark forground, and the the sun was almost in the picture, and the side of the sky was a mid blue.



3) I loaded the file, adjust the exposure a little, add a bit of contrast and play whit the color curve, then add sharpening and I ajusted highlight and filllight. I adjusted the top part and the bottom part separately.



I was arleady able to see banding in the sky.



4) normally I would save the pictue as Jpeg or tiff and that pretty much it.





Probably that using a Nd grad filter would have been a good idea there. And shoot 12 bit beacause I don't really have a choice.

I'm probably sure that the problem is comming from me.... since the beggining of my adventure in the photografy world, I was the cause of the majority of my probleme



But this time I not reallly sur here I did screw up.

And there a part of myself that is always searching a a good reason the buy a D7000.....





Thank for the reply,



Frank

[wim]

Hi Frank,



I'll go through your points one by one, even add a few <img src='http://forum.photozone.de/public/style_emoticons/<#EMO_DIR#>/biggrin.gif' class='bbc_emoticon' alt='' />.

[quote name='Xastoul' timestamp='1336856802' post='18165']

Hi Wim,



Let me descript my "normal" way to process a picture nad maybe you can tell me what's wrong.... ( there may be a lot since I would describe myself as between a maybe good noice and a crappy amateur...)





1) Maye raw editor was a bad wording, I using Bibble 5 wich is acttually a raw converter.



2) In that particular piscture, there was a dark forground, and the the sun was almost in the picture, and the side of the sky was a mid blue.



3) I loaded the file, adjust the exposure a little, add a bit of contrast and play whit the color curve, then add sharpening and I ajusted highlight and filllight. I adjusted the top part and the bottom part separately.



I was arleady able to see banding in the sky.



4) normally I would save the pictue as Jpeg or tiff and that pretty much it.





Probably that using a Nd grad filter would have been a good idea there. [color="#0000ff"]4b) [/color]And shoot 12 bit beacause I don't really have a choice.

[color="#0000ff"]4c) [/color]I'm probably sure that the problem is comming from me.... since the beggining of my adventure in the photografy world, I was the cause of the majority of my probleme



But this time I not reallly sur here I did screw up.

[color="#0000ff"]4d) [/color]And there a part of myself that is always searching a a good reason the buy a D7000.....





Thank for the reply,



Frank

[/quote]

1) That's what I understood. However, I also interpreted the wording as you doing all the editing in RAW and then saving it.



2) Those are the hardest pictures, with a DR of 18 stops or more.



3) I don't know exactly what you mean by highlight and fill light, as I don't know Bibble. With top part and bottom part I assume you mean the tonal curve, which I assume you turned from a straight line to an S-curve?

Actually, with these types of photographs there often is banding even in RAW, as the DR way exceeds the capability of the sensor.



4) <img src='http://forum.photozone.de/public/style_emoticons/<#EMO_DIR#>/biggrin.gif' class='bbc_emoticon' alt='' /> - that is where I normally really start my processing.



4b) Why?

Even so, 12-bit or 14-bit is a moot point really; the lowest two bits generally contain most of the noise anyway. An ND grad or better HDR approach would probably have been better here. That is what I tend to do in cases like these. And even then it is hard to not get banding if you want everything in one nice tonescale. I normally check for the items that are allowed to be blown out, and make sure I expose accordingly (so that only the ones allowed to be blown out are overexposed), and with HDR I'd take a few extra shots at longer exposures to get details in the darker bits.



4c) IOW, not your fault, this is a major problem with photographing very high contrast scenes.



4d) The best reason to upgrade is when you think you can benefit from such an upgrade, whatever that benefit may be <img src='http://forum.photozone.de/public/style_emoticons/<#EMO_DIR#>/biggrin.gif' class='bbc_emoticon' alt='' />. If it has better DR than your current camera, and you need it or want it in your photography, then by all means, go for it.



BTW, if you'd like me to have a look at the file that has this problem, by all means, do upload it somewhere where I can download it, and I'll gladly have a look to see what can be done or what si causing this. I'd preferably have a look at your processed version as well, so I can see better what the problem is. If you'd like me to have a look, just contact me backchannel (via PM, the messenger here), so we can arrange for this to happen, if you like. I'll gladly help out.



Kind regards, Wim