Pages: 1 [2]   Go Down

Author Topic: Pentax 645z and Phaseone  (Read 8350 times)

jwlimages

  • Full Member
  • ***
  • Offline Offline
  • Posts: 135
Re: Pentax 645z and Phaseone
« Reply #20 on: May 27, 2016, 12:51:11 pm »

Hi algrove,

Here's a slightly different perspective:

1. If you've already rendered your Pentax captures to Tiffs, why would you bother trying to process them further with (anyone's brand of) software designed/intended for raw file processing. Why not use "the real thing"?  ;) Finalize them with Photoshop, as that's what it was originally designed for? Now after 20+ years of development, it has tools & capabilities obviously way beyond any make of raw processing software (of course, talking about use on rendered files here).

or

2. If you want to go back & re-process your Pentax .dng capture files (yeah, maybe a herculean task, I know - but if you really want to bring out that amazing image quality...), there is a work-around to let you do this from within CaptureOne. Check out this guy's site: CaptureFix - he's developed a hack to allow processing & even tethered capture using C1.

Disclaimer: I am not associated with this in any way, and not even clear on whether there might be any possible hazards, legal or otherwise, going this route.

I did briefly try an earlier version of his hack - it was really nice to use C1 on my Pentax .dngs, but I had issues with the color, since I didn't have a satisfactory ICC profile for Pentax (if you can master dcamprof, it might be a different story now). As you can tell, going this route would involve a fair bit of DIY technical expertise, but some folks are so inclined...

Good luck!

John
Logged

algrove

  • Sr. Member
  • ****
  • Offline Offline
  • Posts: 262
Re: Pentax 645z and Phaseone
« Reply #21 on: May 27, 2016, 10:28:49 pm »

John
Thanks for your comments. The DNG I want to get into C1 have not been worked on as yet so it would not be redoing what could have been done in LR?PS. Coverting to tiffs seemed like the fsstest way to get those DNG files into C1 if I want to use C1 instead of PS etc.
Logged

jwlimages

  • Full Member
  • ***
  • Offline Offline
  • Posts: 135
Re: Pentax 645z and Phaseone
« Reply #22 on: May 28, 2016, 06:09:20 pm »

Maybe I'm not following you here (and apologies in advance if I've misunderstood and just restating basics you are already well aware of)?

After you convert a .dng to a .tif, it's no longer a raw capture file. Your original Pentax .dng capture is now "fully baked", meaning it's rendered into a conventional pixels image file - even if it's a 16-bit .tif file. There's no going back to alter the conversion from raw .dng to processed .tif (other than going back to whatever app you used for the initial conversion & generating a new .tif). As far as I'm aware, the only way to get CaptureOne to edit Pentax .dng capture files is that guy's "hack" that I referred to earlier (and of course, Phase is probably not too pleased with that situation, so caveat emptor).

One of my points was to question if CaptureOne would be the best choice to edit processed image files (.tifs). Most of C1's strengths apply to processing/converting raw capture files. As capable as it is, I don't think it compares to Photoshop if you're editing already processed image files.

Of course, use whatever app(s) work for you - I mainly wanted to clarify implications of that that raw (.dng) vs. processed (.tif) business.

Happy shooting,

John
Logged

ErikKaffehr

  • Sr. Member
  • ****
  • Offline Offline
  • Posts: 11311
    • Echophoto
Re: Pentax 645z and Phaseone
« Reply #23 on: May 29, 2016, 03:01:31 am »

Hi,

Just to explain a bit…

Tiff files can contain all the tonality information in the raw file. The raw file is in fact a TIFF file, what happens with raw conversion are a few things:

  • The RGBG channels of the raw image are demosaiced, this increases file size 3-6 times. The processing here also handles aliasing.
  • The RGB channel information is converted into some well defined colour space. Phase One pundits may argue that C1 uses camera colour space. Anyway there is a step in processing where RGB numbers are converted into something like colour.
  • At some stage in the processing, a gamma curve will be applied. According to most colour experts, manipulation is best done in linear space. Just as an example, changing contrast will mostly also lead to colour shift in a gamma encoded space.

There is something called parametric or non destructive workflow. One interpretation of the term is to delay raw conversion until it is needed. The workflow works with the raw image and just keeps record of a set of processing instructions that are applied when an image is needed.

Let's assume that Phase One or Adobe comes up with a new demosaic algorithm. In the parametric workflow it can be just dropped in and it will apply to all images. Lightroom has this, they are called Processing Variants, and they go far beyond just the demosaic part. My understanding is that there is something similar in Capture One v. 9.

With TIFFs the initial processing is already done, including demosaic and basic rendition of colour.

Best regards
Erik


Maybe I'm not following you here (and apologies in advance if I've misunderstood and just restating basics you are already well aware of)?

After you convert a .dng to a .tif, it's no longer a raw capture file. Your original Pentax .dng capture is now "fully baked", meaning it's rendered into a conventional pixels image file - even if it's a 16-bit .tif file. There's no going back to alter the conversion from raw .dng to processed .tif (other than going back to whatever app you used for the initial conversion & generating a new .tif). As far as I'm aware, the only way to get CaptureOne to edit Pentax .dng capture files is that guy's "hack" that I referred to earlier (and of course, Phase is probably not too pleased with that situation, so caveat emptor).

One of my points was to question if CaptureOne would be the best choice to edit processed image files (.tifs). Most of C1's strengths apply to processing/converting raw capture files. As capable as it is, I don't think it compares to Photoshop if you're editing already processed image files.

Of course, use whatever app(s) work for you - I mainly wanted to clarify implications of that that raw (.dng) vs. processed (.tif) business.

Happy shooting,

John
« Last Edit: May 29, 2016, 04:34:29 am by ErikKaffehr »
Logged
Erik Kaffehr
 
Pages: 1 [2]   Go Up