Lens cast correction

[Guy Mancuso]

Yes Erich, since 2006 a lot of things have changed, for the good, from each manufacturer, IMO.

I understand and recognize that all applications do somehow have a good working shading tool. Differences can however be found in the way one has to handle the files, how many steps it needs to get a (shaded) DNG ready to go straight into DNG applications, if it allows vignetting correction at the same time when the shading is applied, or needs another step, if it does allow for the softening or not (when the shading is used at the same time by the tool to correct centerfold and dust issues, which leads to differences in IQ) of the shading file, if an automated batch process with different shadings is possible, etc ...

Thanks for your information,
Thierry

With the Sinar setup this sounds like you need to do the shading tool in one program than output to DNG for another program to actually process this. Am I reading this correctly. Reason I ask in C1 all we do is make those corrections with the shading tool( also vignetting control and other fixes)  as you call it than apply that through copy and paste to the images you want to process than go ahead in C1 to output to a final Tiff so everything is within the same program. So really no need to output a DNG unless someone happens to like Lightroom instead. Is this the case that you use two programs to get the final Tiff output, than I can see the worry of extra steps and the timing of that.

[thsinar]

Not at all: the DNG is there, at the first place, no need to output to DNG: IT IS a DNG, from the beginning, with or without shading, lens vignetting correction or whatever. Means no other step, only 1.

Now, if you don't want a DNG, then you can OF COURSE as well do these shading or other corrections and get a Tiff or even Jpg in eXposure.

No need of 2 applications, but you have the possibility and the DNGs directly if you want to go to LR, ACR, Aperture, Raw Developer, etc ..., even in C1.

With the Sinar setup this sounds like you need to do the shading tool in one program than output to DNG for another program to actually process this. Am I reading this correctly. Reason I ask in C1 all we do is make those corrections with the shading tool as you call it than apply that through copy and paste to the images you want to process than go ahead in C1 to output to a final Tiff so everything is within the same program. So really no need to output a DNG unless someone happens to like Lightroom instead. Is this the case that you use two programs to get the final Tiff output, than I can see the worry of extra steps and the timing of that.

[rainer_v]

If i am not mistaken Leaf had a working correction in V8 before that? I also believe the brumbaer tool did not work tethered? It also dropped Leaf support.

This is starting to sound like a play ground conversation,  mine is better then yours.

if i remember well at that time no centerfolds "officially" existed, not by sinar not by leaf and phase and imacon started to admit at that time that color shifts with kodak sensors were more than a problem of a few individual users who had bad luck with their back ( and who always have been the only ones who had this effect ) .

for me this is one of the reasons why mf lost so much attraction for many people, i mean this tools should have existed 3 or 4 years before or at least n the moment the backs have been sold in the market.
 anyway, now the tools are out from all ( what about phocus ?) .
lucky customers who have not been in the first row.

[Guy Mancuso]

Not at all: the DNG is there, at the first place, no need to output to DNG: IT IS a DNG, from the beginning, with or without shading, lens vignetting correction or whatever. Means no other step, only 1.

Now, if you don't want a DNG, then you can OF COURSE as well do these shading or other corrections and get a Tiff or even Jpg in eXposure.

No need of 2 applications, but you have the possibility and the DNGs directly if you want to go to LR, ACR, Aperture, Raw Developer, etc ..., even in C1.

Okay thanks for some reason and maybe what i saw in the past was two programs just was not sure.

[Guy Mancuso]

If i am not mistaken Leaf had a working correction in V8 before that? I also believe the brumbaer tool did not work tethered? It also dropped Leaf support.

This is starting to sound like a play ground conversation,  mine is better then yours.

Actually I don't look at it this way but more to get a understanding how each of these programs work. If there something that another back maker is using than it maybe a good idea that you can get your back maker to look into applying that in your software. Frankly i consider the software and raw processing programs to be extremely important in your buying decision. I happened to use C1 from my Canon 1ds days so for me that was already in play before I bought my back. So it did help in deciding.

[thsinar]

yes, agreed, we have a (IMO) very interesting question (thanks Billy!) and the opportunity to all answer and explain the workflow in details in the different MF solutions, and then discuss the advantages and disadvantages of each, then I don't see it as a "playground discussion".

Thierry

Actually I don't look at it this way but more to get a understanding how each of these programs work. If there something that another back maker is using than it maybe a good idea that you can get your back maker to look into applying that in your software. Frankly i consider the software and raw processing programs to be extremely important in your buying decision. I happened to use C1 from my Canon 1ds days so for me that was already in play before I bought my back. So it did help in deciding.

[Guy Mancuso]

What would actually be a nice idea is each program a video demo from each company actually show how each program works in detail. I think that would be interesting. I know a stretch but a interesting concept. Gotta run to a gig, Have fun.

[David Grover / Phase One]

David, what do you mean the color uniformity correction is saved "into the file"?  If I open that file in Adobe Camera RAW is the color cast still there, or has the color cast been written out of the file entirely?

I was referring to using our Phocus software.  If you wanted to use camera RAW then you would export a DNG file, where the correction would be applied.

[BJNY]

What would actually be a nice idea is each program a video demo from each company actually show how each program works in detail.

This was my hope for this thread.
At the very least, a series of screenshots.

[thsinar]

Well, then I am in line with your expectations, since my screenshots are there!

 

Best regards,
Thierry

This was my hope for this thread.
At the very least, a series of screenshots.

[BJNY]

I need it every step by step.  
Isn't there a utility that allows movie recording of one's desktop?

[free1000]

My Leaf Gain process.

Taking

0) Shoot at ISO 100 to minimise noise. (I find 50 too clean and 200 not always clean enough).
1) After taking the shot, place the diffuser over the lens.
2) Lengthen exposure time by 2 stops take a white shot
3) Lengthen exposure time by 3 stops take a white shot

Aperture must not be changed as this alters colour casts.

Processing

4) Open the leaf MOS files in Leaf Capture
5) Select the files I wish to apply the 'Gain' adjustment to
6) In the setup dialog for the adjustment set the 'falloff' percentage as appropriate (see below)
7) Identify (with a radio button) whether the gain file is the first or last in the shot sequence, its generally last with me.
Close the setup dialog.
9) Select a target directory to save the gain adjusted files to
10) Click on the process button/icon to trigger the creation of the adjusted Raw files

11) Import adjusted files into Lightroom for basic grading and further editing.

NB:
In step 6: I try to mimize the use of falloff correction as I find it affects overall exposure level. I generally need a max of 50% with the 24mm digitar but usually get away with less, maybe 0-25% for my other LF lenses.

This procedure also eliminates any errant dust spots, initially I was annoyed at having to use the gain step, but the advantage of zapping dust makes the initial up front effort less problematic as it saves some time in post.

[BJNY]

Thanks, free.

Is the falloff correction infinitely adjustable, or is it in 25% steps.

If the falloff correction affects exposure level, does a lighter capture solve this?

Billy

[yaya]

This was my hope for this thread.
At the very least, a series of screenshots.

Very straight forward in our case:

Post capture:

1. Choose "mos" as your output format
2. Press "Settings"
3. Set the order of the files First/ Last and the falloff correction value (anything from 0-100)
4. Press OK
5. Set your destination folder (I usually use the captures folder) and hit "Process"

This takes 3-4 seconds per file on a decent machine and while it's running you can set your next set, shoot, process into another format or whatever.

When tethered you can either load a "user" calibration file to the back:


(it can be used for untethered work as well, for example on an ALPA TC with no movements)

Or you can use a wizzard to create a user gain file:


Etc.

Yair

[ericstaud]

I was referring to using our Phocus software.  If you wanted to use camera RAW then you would export a DNG file, where the correction would be applied.

Thanks David.  

With Leaf, the RAW file is re-written without the color casts (if I view the RAW in bridge the color casts are no longer there).  With Phase, the cast correction is a set of processing instructions (if I view the RAW is Bridge the casts are still there).

What I was trying to understand was if Hasselblad was treating the process more like Leaf (re-writing the RAW file), or like Phase (creating a set of processing instructions).

The Phase method offers the advantage of speed, but until they came out with the DNG option it was impossible to correct the raw files and then process them in third party software.  It didn't bother me too much because Capture One is very good with the phase files.

The Leaf method was (in the past) slow, but the re-written raw file was totally free of color casts and could be processed through any application.  I think the process is much quicker now.

One reason this issue is important is because Phase dropped support for corrections made in earlier versions of C1 Pro.  If I want to process any pictures I made previous to using 4.5, then I have to re-do to LCC correction each time.    The Leaf files I have from 2006 are all re-written files without casts.  They are, in this way, more archival and more portable/compatible than the Phase One RAW files.

Both Leaf and Sinar are generating new files where the color cast simply don't exist.  I understand that with Phase and Hasselblad that it is possible to output a "cast-free" DNG file, but it is not clear to me how the original Hasselblad RAW file is handled.

[David Grover / Phase One]

No problem Eric!

When I am back in the office on Thursday Ill take Yair's lead and show you the how-to with a few screen dumps.

I hope that is soon enough for you.

Best,



David

[Kumar]

No problem Eric!

When I am back in the office on Thursday Ill take Yair's lead and show you the how-to with a few screen dumps.

I hope that is soon enough for you.

Best,



David

Please do this for both Flexcolor and Phocus.

Kumar

[free1000]

One reason this issue is important is because Phase dropped support for corrections made in earlier versions of C1 Pro.  If I want to process any pictures I made previous to using 4.5, then I have to re-do to LCC correction each time.    The Leaf files I have from 2006 are all re-written files without casts.  They are, in this way, more archival and more portable/compatible than the Phase One RAW files.

Both Leaf and Sinar are generating new files where the color cast simply don't exist.  I understand that with Phase and Hasselblad that it is possible to output a "cast-free" DNG file, but it is not clear to me how the original Hasselblad RAW file is handled.

Ouch having to re-do cast corrections sounds like quite an irritation, I didn't realise how lucky I was with the Leaf gain.  The re-writing of files is a real boon if you want to (as I do) finish post in a variety of different raw converters as I use Lightroom for bog standard stuff and Raw Developer occasionally when I want to eke out the maximum detail.
 
Just in case it wasn't clear to BJNY's question, you can vary fall off correction in LC at any amount between 0 and 100%

[Kumar]

No problem Eric!
When I am back in the office on Thursday Ill take Yair's lead and show you the how-to with a few screen dumps.
I hope that is soon enough for you.
Best,
David

Hello David,

If you're not too busy reading the financial papers...

Thanks,
Kumar

[David Grover / Phase One]

Hello David,

If you're not too busy reading the financial papers...

Thanks,
Kumar

;-)

Hey Kumar,

Sorry this thread slipped my mind!  Ill do it now.

David