As the off-topic-guy I am I posted a DNG profile for the Pentax 645z in this other thread
http://forum.luminous-landscape.com/index.php?topic=104101.0 To gain a bit better visibility for Pentax 645z users I post here in a new topic.
I don't own a Pentax 645z but I've seen some interest in improving on the default ACR profile, so I just made a quick DCamProf profile for demonstration. I think it's unfortunate that the Pentax with the great Sony MF CMOS sensor shouldn't have good profiles like other MF offers with the same sensor (IQ250, Credo 50).
As before the profiles attached here are made from this online CC24 shot:
http://www.imaging-resource.com/PRODS/pentax-645z/645ZhVFAI000100.DNG.HTM . That shot is made in artificial daylight and suffers a bit more glare than a really high quality shot colorchecker shot would do, but I think it still did well as basis for a D50 profile. It would be great to have a Tungsten (StdA) shot too to make a dual-illuminant profile like the bundled is, but then someone needs to provide a shot. Tungsten+D65 is the standard combo for dual-illuminant, but StdA+D50 is fine too.
I've re-rendered the profiles from the original thread and added the ColorMatrix from Adobe's bundled profile. The reason for this is to avoid a white balance shift (caused by an unfortunate design decision by Adobe), discussed here:
http://www.ludd.ltu.se/~torger/photography/camera-profiling.html#white_balance_shift it won't affect color rendition, as a different matrix is used for that (ForwardMatrix). For the same reason this is a "fake dual-illuminant" profile, it says it's a StdA+D65 profile but it's in actuality only D50, this to report the exact same color temperature as the bundled profile.
The curve in the profile is Adobe's default tone curve, just as the bundled profile. I don't have Pentax's own Digital Camera Utility 5 which I otherwise would check if they have some different contrast there and match the curve with that, it's probably a better reference than Adobe, but possibly it's the same result.
The DNG files I've got have embedded JPEG in them, usually one can look at them to get the camera's own rendering. That rendering is simply the default Adobe curve with the embedded matrix (no LUT), ie very simplistic rendering. I'm surprised if that corresponds to in-camera JPEGs. Maybe the embedded preview in PEFs looks like the DCU5 output? Anyway, with the DNG files and no DCU5 software there's no ability to try relating to the camera's native rendering, unless that really happens to be matrix+acr default curve (which I doubt).
Suggested further work would be:
- Get StdA/flash/D65 shots CC24 to make profiles for other light conditions / DNG profiles
- Relate to the native DCU5 rendering, mainly the tone curve, often it's preferable to mimic at least some aspects of the in-camera/native rendering
- Fine-tune the look
- High saturation blue may have a clipping issue (I've seen it in some test pictures), can be adjusted
I have attached one with an example subtle look adjustment, as described here:
http://www.ludd.ltu.se/~torger/photography/files/custom-look.jsonThis look is a generic one, not made specifically for the Pentax. Looks does not necessarily need to be made specifically per camera, but for example a very subtle skin-tone hue change would likely be camera specific, while changes like warmup of green/yellow midtones are more generic.
The difference between DCamProf and software like X-rite is that quite much effort has been put into rendering colors well
after the tone curve has been applied, while most (all?) commercial profile makers make colorimetric base profiles and just slam a tone curve on top and let it become what it becomes. A lengthy discussion about this can be found here:
http://www.ludd.ltu.se/~torger/dcamprof.html#tone_curvesDCamProf is probably not the best profile maker if you're going to make a reproduction profile (no tone curve), then the commercially available alternatives are probably better. But for general-purpose photography it does very well. The intention is to be able to match and exceed what the best bundled profiles provide (the bundled profiles are made with in-house software not available to consumers).
While the look can be fine-tuned, and small improvements of color checker shots can be made, if you don't like the look at all of these two profiles, then DCamProf profiles are not for you. These profiles are very close to what a "final" profile would look like, at least in lights close to D50. I would myself not doubt using them in production, especially after looking at the result of Adobe's bundled profile