Pentax 645Z vs Phase One & Hasselblad

[ErikKaffehr]

Hi,

Would be interesting, would we have three comparable raw files from the three cameras.

Best regards
Erik

If someone will want to compare the image quality of these three cameras on equal post processing, I have the software to convert Hasselblad and Pentax raws into a Phase One raw, and then you can process all in C1 as if they were IQ250 files. Assuming CFA is equal and there's not too much cooking in the hardware, the colors should match.

The reason I have this is to provide my Lumariver HDR users that own Phase One backs with a better raw workflow (C1 is not too good with DNG). That it's possible to convert other camera formats into IIQ was a side effect, and will probably not be in the released product. Phase One locks out the other Mf cameras for a reason and they probably won't like if we open this up. But I can convert a few files for demonstrational purposes.

[torger]

Would be interesting, would we have three comparable raw files from the three cameras.

Yep, I've tested the concept by converting a Hasselblad CF-22 3FR into a Phase One P25+ IIQ, and colors turned out well. With the H5D-50c, Pentax 645z and IQ250 if shooting the same subject it could very well turn out that the files look more or less exactly the same. I'm not sure though, I think (don't know for sure) that Hasselblad does some slight raw data cooking for color in their backs, as a part of their "Hasselblad Natural Color Solution", and that would mean that there would be some slight color differences. Differences in IR filter could also affect color somewhat.

What I expect the experiment to show is that the differences between these systems is not about the back's image quality, and you got to justify the $20k extra for the IQ250 with other properties. Actually, I think the Capture One converter is a pretty strong component for many that make them choose IQ250, that's why I think it's an important business decision by Phase One to not support Hasselblad or even worse Pentax 645z, because then they would remove one of the key differentiators.

I'm looking for a Hasselblad H5D-50c raw file for the moment, not really for this (I'd try it though out of curiousity) but for general 3FR format testing in the raw projects I'm involved. Haven't succeeded getting one yet though . For 645z there's some waiting to do until it's released of course.

[eronald]

Do you have software to write synthetic raws in some known raw format?
I would like to do some raw converter tests.

Edmund

If someone will want to compare the image quality of these three cameras on equal post processing, I have the software to convert Hasselblad and Pentax raws into a Phase One raw, and then you can process all in C1 as if they were IQ250 files. Assuming CFA is equal and there's not too much cooking in the hardware, the colors should match.

The reason I have this is to provide my Lumariver HDR users that own Phase One backs with a better raw workflow (C1 is not too good with DNG). That it's possible to convert other camera formats into IIQ was a side effect, and will probably not be in the released product. Phase One locks out the other Mf cameras for a reason and they probably won't like if we open this up. But I can convert a few files for demonstrational purposes.

[torger]

Do you have software to write synthetic raws in some known raw format?
I would like to do some raw converter tests.

The short story is that I unfortunately probably do not have the program you need for your testing

The full story is this; I contribute to RawTherapee (open source project) where I've made some key contributions to support medium format gear, and I'm also one of the developers making the commercial software Lumariver HDR, which does high class merging, tonemapping, and flatfield (LCC) correction and supports raw-in-raw-out workflow, primarily native-raw-in-DNG-out. The commercial value of supporting MF gear is not exactly big, but as I'm a MF shooter myself and need those features myself we do it anyway.

Anyhow, Capture One is popular among MF shooters, and Capture One happens to be poor at tonemapping (good for us) but also quite poor at dealing with DNG files (bad for us), which cripples Lumariver HDR's raw-in-raw-out workflow. The solution to this problem was to take the most popular MF format, Phase One's IIQ, and make a format writer for that. So then you can take your Phase One native IIQ raw, import that to Lumariver HDR, LCC-correct (crosstalk cancellation feature coming), tonemap, and then export to an IIQ raw which you then open as any normal raw file in Capture One. (This feature has not yet been released.)

As a side effect of having an IIQ writer it's also possible to import say a Hasselblad H5D-50c or Pentax 645z file and write an IQ250 IIQ file. It will only work color-wise if sensor CFA matches, and since Capture One ignores lots of its own IIQ tags and just goes on the model id tag, sensor size must also match an existing Phase One digital back model. The IIQ writer is not part of my open source effort so I can't just give it away. The feature is intended for Phase One digital back owners, so in the released product we will most likely not enable the possibility to import another format and write an IIQ (it won't work in most cases anyway for the reasons described).

I'm myself very curious about comparing these three cameras though, so if anyone provides raw files to me I can convert them so people can play around with it.

If you with synthetic raws means synthetic image data content it's not adapted to do that (ie the raw image data must come from a raw file). It's quite easy to add such a feature though, but we've had no reason to do so so far. The two raw formats we write is DNG and IIQ, and as said the only reason we write IIQ is because Capture One's DNG support is not satisfactory, at least not yet.

[Paul2660]

Torger.

Any chance lumariver HDR will be ported to a win platform in the future?

Thanks
Paul

[ErikKaffehr]

Hi,

Realising that Lumariver HDR can handle raw input and output I got so impressed I ordered it directly, after checking the documentation.

One thing I would suggest you could look into  would be this:

The way I use the gradient tool in Lightroom is mostly with the "Highlights" slider, this gives an ample compression of highlights without affecting midtones and darks very much. So, I can darken the sky without affecting say treetops. Something similar could be nice.

I am normally not that much in HDR, because I feel that I seldom need it. But, I'm going on a workshop in the Dolomites and I understand that we are going to look into HDR, and I felt it may be a good opportunity to test.

Best regards
Erik

The short story is that I unfortunately probably do not have the program you need for your testing

The full story is this; I contribute to RawTherapee (open source project) where I've made some key contributions to support medium format gear, and I'm also one of the developers making the commercial software Lumariver HDR, which does high class merging, tonemapping, and flatfield (LCC) correction and supports raw-in-raw-out workflow, primarily native-raw-in-DNG-out. The commercial value of supporting MF gear is not exactly big, but as I'm a MF shooter myself and need those features myself we do it anyway.

Anyhow, Capture One is popular among MF shooters, and Capture One happens to be poor at tonemapping (good for us) but also quite poor at dealing with DNG files (bad for us), which cripples Lumariver HDR's raw-in-raw-out workflow. The solution to this problem was to take the most popular MF format, Phase One's IIQ, and make a format writer for that. So then you can take your Phase One native IIQ raw, import that to Lumariver HDR, LCC-correct (crosstalk cancellation feature coming), tonemap, and then export to an IIQ raw which you then open as any normal raw file in Capture One. (This feature has not yet been released.)

As a side effect of having an IIQ writer it's also possible to import say a Hasselblad H5D-50c or Pentax 645z file and write an IQ250 IIQ file. It will only work color-wise if sensor CFA matches, and since Capture One ignores lots of its own IIQ tags and just goes on the model id tag, sensor size must also match an existing Phase One digital back model. The IIQ writer is not part of my open source effort so I can't just give it away. The feature is intended for Phase One digital back owners, so in the released product we will most likely not enable the possibility to import another format and write an IIQ (it won't work in most cases anyway for the reasons described).

I'm myself very curious about comparing these three cameras though, so if anyone provides raw files to me I can convert them so people can play around with it.

If you with synthetic raws means synthetic image data content it's not adapted to do that (ie the raw image data must come from a raw file). It's quite easy to add such a feature though, but we've had no reason to do so so far. The two raw formats we write is DNG and IIQ, and as said the only reason we write IIQ is because Capture One's DNG support is not satisfactory, at least not yet.

[eronald]

Hi,

 I had a feeling somehow that being able to tweak a raw file and then dump it back into Raw so it can be read by an existing converter might allow some interesting experiments eg. corrections (crosstalk, flare; deconvolution), superposing exposures etc, but maybe it is irrealistic to expect to do it in a general way. Software is complex, I guess. I'm a "computer scientist" by trade which means I deal in small algorithms of a page or so, not "software". Bricks rather than buildings.

Edmund

The short story is that I unfortunately probably do not have the program you need for your testing

The full story is this; I contribute to RawTherapee (open source project) where I've made some key contributions to support medium format gear, and I'm also one of the developers making the commercial software Lumariver HDR, which does high class merging, tonemapping, and flatfield (LCC) correction and supports raw-in-raw-out workflow, primarily native-raw-in-DNG-out. The commercial value of supporting MF gear is not exactly big, but as I'm a MF shooter myself and need those features myself we do it anyway.

Anyhow, Capture One is popular among MF shooters, and Capture One happens to be poor at tonemapping (good for us) but also quite poor at dealing with DNG files (bad for us), which cripples Lumariver HDR's raw-in-raw-out workflow. The solution to this problem was to take the most popular MF format, Phase One's IIQ, and make a format writer for that. So then you can take your Phase One native IIQ raw, import that to Lumariver HDR, LCC-correct (crosstalk cancellation feature coming), tonemap, and then export to an IIQ raw which you then open as any normal raw file in Capture One. (This feature has not yet been released.)

As a side effect of having an IIQ writer it's also possible to import say a Hasselblad H5D-50c or Pentax 645z file and write an IQ250 IIQ file. It will only work color-wise if sensor CFA matches, and since Capture One ignores lots of its own IIQ tags and just goes on the model id tag, sensor size must also match an existing Phase One digital back model. The IIQ writer is not part of my open source effort so I can't just give it away. The feature is intended for Phase One digital back owners, so in the released product we will most likely not enable the possibility to import another format and write an IIQ (it won't work in most cases anyway for the reasons described).

I'm myself very curious about comparing these three cameras though, so if anyone provides raw files to me I can convert them so people can play around with it.

If you with synthetic raws means synthetic image data content it's not adapted to do that (ie the raw image data must come from a raw file). It's quite easy to add such a feature though, but we've had no reason to do so so far. The two raw formats we write is DNG and IIQ, and as said the only reason we write IIQ is because Capture One's DNG support is not satisfactory, at least not yet.

[Telecaster]

I'm a "computer scientist" by trade which means I deal in small algorithms of a page or so, not "software". Bricks rather than buildings.

Hehe, I was once part of a programming team nicknamed "The Bricklayers" due to our (relatively early) enthusiasm for OOP. Our fantasy rock & roll band got the name ARP/RARP & the WAN Woes, which I still wish I'd thought of.   

-Dave-

[torger]

I had a feeling somehow that being able to tweak a raw file and then dump it back into Raw so it can be read by an existing converter might allow some interesting experiments eg. corrections (crosstalk, flare; deconvolution), superposing exposures etc, but maybe it is irrealistic to expect to do it in a general way. Software is complex, I guess. I'm a "computer scientist" by trade which means I deal in small algorithms of a page or so, not "software". Bricks rather than buildings.

Yes, that's what we intend with Lumariver HDR. I have a crosstalk cancellation prototype algorithm ready and working for example. In the current version you can merge several exposures into one (HDR) so you get a super-low-noise raw file into your raw converter. Tonemapping you can apply to the raw file and export a "cooked" one, which is a good idea especially for Capture One whose own tonemapping is not particularly good if you ask me.

Many corrections, like deconvolution is probably better made after demosaicing though, so it's a mix of things. Raw converters like lightroom capture one etc already today does some corrections pre demosaicing but most post.

The reason we write raw is because we're doing a small speciality software which focuses at being best at a relatively narrow set of features, and as such it should work in various workflows including your favourite raw converter. A big player like Adobe has little/no reason to have raw-in-raw-out support as they offer software for virtually everything in the whole processing chain and want you as a user to use only their products of course.

Getting raw files to add support for medium format cameras have been proven to be quite difficult though, especially for Hasselblad for some reason, probably because it's less used in tech cameras, I get most my test files from the tech cam community which somehow seems a bit more open. If you intend to buy a camera I suppose it's easy to get files, but if you say it is to support the camera in third-party software it's more difficult to get response.

(Better bring this on topic soon or I sound too much like a salesman... hehe)

[gerald.d]

torger -

If you ever need more RAW files from IQ250, P45+ Achromatic or IQ180, just ping me.

Kind regards,

Gerald.

[ErikKaffehr]

Gerald,

I appreciate you helpful and positive attitude!

I can add that I started playing with Lumariver HDR and it holds a lot of promise. Works better than anything I tried, but I am not a HDR freak.

The raw to raw workflow holds some promise, even if I just tested dng to dng. Writing to IIQ is still in development, but your files may be most helpful.

Needlessly said, I obviously bought a license, this is HDR stuff I am going to use!

Best regards
Erik

torger -

If you ever need more RAW files from IQ250, P45+ Achromatic or IQ180, just ping me.

Kind regards,

Gerald.

[gerald.d]

Gerald,

I appreciate you helpful and positive attitude!

I can add that I started playing with Lumariver HDR and it holds a lot of promise. Works better than anything I tried, but I am not a HDR freak.

The raw to raw workflow holds some promise, even if I just tested dng to dng. Writing to IIQ is still in development, but your files may be most helpful.

Needlessly said, I obviously bought a license, this is HDR stuff I am going to use!

Best regards
Erik

I simply think torger deserves all the help he can get. He has gained some pretty fundamental insight into issues which have affected me, and which Phase One were unable to solve.

I'm fortunate to have access to those three backs, pretty much the entire Rodenstock line of lenses (I'm just missing the 28), and a whole bunch of Canons too, so I can probably supply more back/lens combination files than most others could.