[Richard Day]

I have done some tests using the default settings of ACR 3.7 (both 3.7 and Pentax 1.00 settings) against Pentax Photolab and Silkypix (v3).

I have longed for Adobe to get their ACR colour profiles to be better, i.e. accurate (for almost any camera!), and hoped that the latest v 3.7 for the K10D would be better. Unfortunately things don't change and it is still some way off, so it's out with the greytag chart and fudging again!

There is no difference between using PEF or DNG Raw files.

Here are my results on two different images, as you can see PPL and SP are quite similar, but ACR (both profiles) are somewhat different! As the portrait is one of my grandsons I can state that the Silkypix shot is probably the closest, the PPL is slightly cool. The building shot really shows up the ACR difference, especially in the brickwork and concrete rendering colours, which have a distinctive reddish/orange cast, as before.

Building shot (High contrast)




Portrait shot



I shall post my callibration settings when I've done them, just in case anyone else is interested.

[NaClH2O]

Thanks Richard for posting these, highly informative. Have you any experience with Lightroom? Being an Adobe product I would expect to see it similar to ACR but I've seen nothing like your complete and thorough comparison.

NaCl(still using ACR, but looking, looking....)H2O

[jfdavis58]

OK, I see; but what did you expect?

Identical results?

You are aware that there are at least seven 'different' algorithms for converting RAW to RGB? And that four of them have been judged to be 'unique'--mathematically different in approach and result, yet in some sense still adequate for the task? And in many instances impossible to differentiate?

Have you done this 'by the numbers'? You know how little the differences really are from shot to shot?

In the kids face its +/-3 to 5; the building is +/- 7-10. But that the RGB proportions are statistically indistinguishable?

I'm tempted to wig-out and get sarcastic with some suggestion that perhaps you want the sun and the moon too, but I'm just not sure you would get the point.

I have longed for Adobe to get their ACR colour profiles to be better, i.e. accurate (for almost any camera!), and hoped that the latest v 3.7 for the K10D would be better. Unfortunately things don't change and it is still some way off, so it's out with the greytag chart and fudging again!

Quantify this! Is it mathematical perfection you want-google Tom Fors?

[oxford_artist]

I hope I'm not jumping in here, but that's a strange response from jfdavis58. Richard posts some pics to show relative renders with different engines together with his opinion that SilkyPix gets closest to the original "out-of-the -box". What's wrong with that? Simply informative with no other implications and he gets that sort of sarcastic comment. Doesn't seem very friendly, or even helpful, to me.

[Richard Day]

OK, I see; but what did you expect?

Identical results?

You are aware that there are at least seven 'different' algorithms for converting RAW to RGB? And that four of them have been judged to be 'unique'--mathematically different in approach and result, yet in some sense still adequate for the task? And in many instances impossible to differentiate?

Have you done this 'by the numbers'? You know how little the differences really are from shot to shot?

In the kids face its +/-3 to 5; the building is +/- 7-10. But that the RGB proportions are statistically indistinguishable?

I'm tempted to wig-out and get sarcastic with some suggestion that perhaps you want the sun and the moon too, but I'm just not sure you would get the point.



Quantify this! Is it mathematical perfection you want-google Tom Fors?

Feel free to be sarcastic, if it helps you, I don't mind!

Yes, I did expect something much closer, at least something similar to the result from Silkypix. I also do understand that there are several different algorithms and all will give varying results. I just feel that the results from ACR 3.7 are beyond "acceptable" variations. The building shots tend to show it more than the portrait, even so, the skin tone and hair colour is far from the truth.

I am aware of Tom Fors and calibration of ACR.

I will be doing a proper Greytag test chart callibration as outlined by Rags Gardner to get a closer setting.
Camera Calibration

I feel that Adobe doesn't do itself any favours by consistently producing profiles that are quite inaccurate, I have the same challenge for both my istD and Panasonic LX-1 and some images that I also have from Canon and Nikon Raw files.

Considering that many folk are using CS2 and many are contemplating Lightroom, which uses the same basic colour engine as ACR. I feel it appropriate that I highlight something which I feel to be quite important.

If people choose to disagree or ignore my comments, may their God be with them, I don't mind either way. However some may be grateful, if so, I'm happy about that as well.

[Richard Day]

Thanks Richard for posting these, highly informative. Have you any experience with Lightroom? Being an Adobe product I would expect to see it similar to ACR but I've seen nothing like your complete and thorough comparison.

NaCl(still using ACR, but looking, looking....)H2O

I expect it to be very similar. I haven't tried Lightroom v1.0 yet, but from what I remember of the Beta version, you couldn't save a profile as you can in ACR. Someone please correct me if I'm wrong.

I will download it and give it a try, also Bibble as well, if I have time.

[Jonas B]

OK, I see; but what did you expect?
Identical results?
-snip-
Quantify this! Is it mathematical perfection you want-google Tom Fors?

Somebody had a bad day I think.

Btw, Fors showed the way but using Rags script is a bit better in practise.

[Richard Day]

Somebody had a bad day I think.

Btw, Fors showed the way but using Rags script is a bit better in practise.

Hi Jonas

Always the psychologist I believe? - Watching for aberrant behavior!

I trust that you and Elisabeth are well?

Best regards from Pat and me.

[jfdavis58]

It was the start of the day; and except for some RiceHigh, I slept well, my breakfast was good and the days start were just fine. I just don't 'deadpan' anything; I'm passionate, commited, aggressive, immersed in photography. It's too bad so many here are just into tip-toeing through the day. I go out most days and grab it by the neck just to see what happens.

[jfdavis58]

One post and you pick at me? A bit too cozy for sure-we need to get to know each other a bit before you start judging me--or should we just save time and effort and I can start calling you names, too????

[jfdavis58]

OK, but that's still a cheesy answer.

Three different monitors and crossing the LCD/CRT bondary once I like the medium ACR kid best; default Pentax 1 curve second best; both on the left are too cyan/blue; the top middle kid is muddy in both white and gray-same with pentax linear but not as bad.

Photolab and ACR medium(def) have the best-cleanest-sunlight in the street---this matches tone in the clouds and sky; the clear building facade in the silkypix version is downright yellow--that's a 'need to see/know the building thing---I don't, advantage Richard-----but...

I've seen bigger variation from the same image on two different monitor/printer(home) and printers(out). In fact I've seen this much difference in images at different points in the same batch!

I'm tempted to say that you are biased by familiarity with both the'originals' of both images and Siklypix(mispelled on purpose--see I do have a small sense of humor). But, heck I don't know--tell what you see and think; that would be more fun anyway.

[jfdavis58]

OH, thanks for the reference too; just what I need, more reading.

[Jonas B]

It was the start of the day; and except for some RiceHigh, I slept well, my breakfast was good and the days start were just fine. I just don't 'deadpan' anything; I'm passionate, commited, aggressive, immersed in photography. It's too bad so many here are just into tip-toeing through the day. I go out most days and grab it by the neck just to see what happens.

Ok. Now you know what happened.

For photography I'm passionate (in my own way), commited (to my ideas), immersed (in the limited fields that interest me). Tip-toeing has never been my way.

What do you use the aggressive part for?

[Jonas B]

Hi Jonas

Always the psychologist I believe? - Watching for aberrant behavior!

I trust that you and Elisabeth are well?

Best regards from Pat and me.

Part time shrink, yes... A bad habit, I know. I'm always struggling with forum psychology.

Thanks you, yes, we are fine and I hope you are too.

Now that we are drifting away and going OT, may I ask: Do you know if the new long DA* primes are made to cover a somewhat larger future sensor?

all the best,

[slip]

I have done some tests using the default settings of ACR 3.7 (both 3.7 and Pentax 1.00 settings) against Pentax Photolab and Silkypix (v3).

I have longed for Adobe to get their ACR colour profiles to be better, i.e. accurate (for almost any camera!), and hoped that the latest v 3.7 for the K10D would be better. Unfortunately things don't change and it is still some way off, so it's out with the greytag chart and fudging again!

There is no difference between using PEF or DNG Raw files.

Here are my results on two different images, as you can see PPL and SP are quite similar, but ACR (both profiles) are somewhat different! As the portrait is one of my grandsons I can state that the Silkypix shot is probably the closest, the PPL is slightly cool. The building shot really shows up the ACR difference, especially in the brickwork and concrete rendering colours, which have a distinctive reddish/orange cast, as before.

Building shot (High contrast)




Portrait shot



I shall post my callibration settings when I've done them, just in case anyone else is interested.

Hi Richard

thanks for sharing these comparisons with us.
I just wanted to say (right or wrong) that when you use the different default settings in camera raw, that what you see isn't always EXACTLY what your camera recorded?
if you want to see exactly how your camera took the photo, turn off all the default setting except for (I only know Photoshop) the color temperature which is by default in photoshop the exact way the camera recorded it.
If the photo you open is one stop dark, then that is exactly what was recorded on the sensor.
sometimes when I open up ACR the automatic settings really are so far off I just set them myself. other times it is close, but more often then not, it is too bright compared to the acual scene I shot.
here is some information to back what I am saying

http://www.adobe.com/digitalimag/pdfs/phscs2ip_camraw3.pdf

here is another thing I found very interesting and helpful from adobe about ACR and not leaving it on defaults"

Leave Exposure at 0. If you find that you consistently need to move the Exposure slider in one direction, it’s time to check your metering (for example, a camera’s nominal ISO 100 may be closer to ISO 75 or ISO 125). If that’s the case, it’s better to dial in the appropriate exposure compensation on your camera.
Leave the White Balance setting at As Shot, so that Camera Raw can adapt to different white balances.

hope this sheds some light into your findings



randy