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View Full Version : Negative to positive workflow for CaptureNX2!



arthurking83
26-01-2012, 9:18pm
Hey all, just posting some info on the process of converting negative film into positive 'prints' using CaptureNX2.

First some background:

About 2 years back I had the opportunity to purchase a roll of film, mainly due to some left over money I had.
Now that I'm into the digital realm, and film was firmly behind me, I loved the digital method of photography.
Many moons ago, back in upper high school, I fell into Media studies and liked photography and video aspects of the subject.
So, at any opportunity I could, I'd shoot some photos with whatever came to hand, and I remember that a lot of polaroids came to hand in those days.

I never liked the process of development as the odours of the chemicals made me nauseous, and I had to be excused back in those days from the school darkroom.

So, some 20 years later I found myself shooting a roll of film once again, and having got back the negs and the prints, as well as a disc of the prints in a digital(jpg) format .. I was mightily unimpressed.
The camera used was my lil Rollei 35, with no real focusing ability as it isn't a range finder .. just a simple viewing window with a rough outline of where to frame. Focus was by estimating the distance to subject.
Film used was a roll of Ektar 100, and for the sake of memorising the Rollei's settings, I shot the same scene(as best as I could) with the D300 and an approximately similar focal length(format accounted for).
Because I was unimpressed by the prints and the jpg scans I then had the idea of acquiring a high quality scanner for both this film scanning and general use in the office.. so a dedicated film scanner was not in the running.
I ummed and ahhed a lot, and then decided to go with the other option of acquiring a digital camera copying device in the form of a bellows and a film copy attachment to achieve the task of copying the negs for digitsation.
The jpgs I received from the processing lab had a resolution of only 3000x2000(D70 sized 6Mp output). The doofuses at he processing lab missed the periphery of the negs in the prints and the scans, so I wanted to do better. The chopped bits were not much, nor important, but that's beside the point .. I simply wanted to do better than they did.
Print quality at 4x6 was as expected, but the biggest issue was that the Rollei, being so old now must have a 'dragging shutter', and even tho I compensated by -1Ev for the film in most cases, they still came out more over exposed than the D300 files.
From what I remember of the D300's rated ISO levels, compared to a standard film equivalent ISO exposure rating the D300 is about 0.7Ev brighter, hence the compensation. But as I sad the prints and scans indicate more over exposure than I expected, most certainly due to an inaccurate shutter on the Rollei.

now I got the PB-4 bellows and I have everything else I need, so for a few days back in early December, I started to see how this process of copying film via the camera works.
But I hit a serious snag, in that my preferred image editing software Nikon's, CaptureNX2 has no option to invert colour.
To be expected actually, and as Nikon have(had) a series of dedicated film scanners, they would want people to avoid them and choose a digital camera option instead.

But I went on the lookout for other options, and to begin with, I used CNX2 for the initial process of adjusting the neg, and then decided to use a program called Paint.net for the final conversion to positive(print). But this print would only be saved as a jpg or tiff file, so I'd lose any hope to maintain the raw format for the raw neg converted into positive(as I really wanted).

The process was slow and tedious as you have to work in reverse on the neg, and estimate the amount of processing required on the neg raw file and then convert to positive.
For this one single image, I have about 20 variously edited and colour corrected versions of the file just to try to get something resembling a print output file.
Very slow, very tedious very annoying and very easy to give up on the process .. so I did.
Recently Chimbu's questions and threads on copying film onto digital and some of his images reminded me of some of the things I've forgotten about recently.
As the bellows is great for macro work, I left the film conversion on the back burner, and worked with it more on the macro front. Along with a $3 lens I also purchased, I'm having fun using this gear for macro .. but I had to get back to the film copy quagmire I wanted to complete.

So today or last night I did another search for a friendlier process to convert the negs to print, and stumbled on a post on PetaPixel about our brain's ability to process images in certain ways.
Some insightful info on that page that was about to help me get back into it again. But at the same time, I asked a simple question on another site about for any tips on how to also achieve this goal using pure processing methods, and not PS/CS if possible. I wanted to maintain the NEF format if possible. And that eventually came back positive too, with a slight variation on the tips I received on the processing method.

First up the visual method:

Completely unknown to me is that (In Win7) you can use the Magnify tool to invert the colours of your screen! :th3:
This is close to what I needed, as my initial bottleneck was in processing the negs in the initial phase to get WB right. The hard part is that everything is inverted to begin with and that you need to work in the opposite manner to what is usual. Warm it up to cool it down and vice versa.. etc. Darken to brighten, and brighten to darken. Add contrast and it looks washed out.
Very frustrating trying to edit a negative at this stage. So in using Win7's Magnify tool, and selecting the colour inversion option, your screen will invert the colours from positive to negative, and importantly for me, neg to positive! Yay!
But even tho the screen is still easy to see in reversal mode, it was painful to use. So I chose the 'lens' view option, which places a square loupe where the mouse cursor is positioned at. Perfect as this is where I required the editing to be done(via CNX2).
This god damned annoying Magnify tool which used to drive me mad, is now partly my saviour.
I have a M$ mouse kb setup which uses MS's advanced tools for some shortcuts. The mouse has two extra buttons, one of which is set to initiate the magnify tool, and even tho I've switched this off a few times, when ever you update the drivers, the button reverts back to default. You accidentally nudge the button and the magnify tool pops up.
Annoying to say the least .. only until now ;)
So with this colour reversal loupe at hand, editing the neg was much simpler and easier, and I only needed to create one copy of the negative raw file, and when set to this point, only one version of the 'print file' :th3:

I was happy enough until I received a reply on this other site, where I was alerted to a process in LR3, where you invert the colours of a file, by using the curves tool to the extreme.
I've no un-installed LR3, but I tried the same process in CNX2 and I almost got there.
The reply also contained info on the process, of a possible requirement of some colour balance adjustment once the extreme curves adjustment was set.
So the process of colour inversion using the curves tool was explained to me as such:

Using the curves too, pull the highlights curve down to the shadows level, and to do the opposite for the shadow curve, in dragging it back up into the range of the highlights.
This initially distorts the image to an almost positive variation, but with some extreme colourisation. This is where the tip mentioned to adjust some colours .. but no matter wha5t I tried, in terms of colour adjustment, I couldn't get any part of the image to imitate a print look. I pushed every button, slid every slider and so on, and I wasn't going to stop until the PC either smoked up or popped or until the image popped.
And then I stumbled on the shadow/highlights and contrast slider adjustment, which did the trick!! Yay again. :D

So the final step(at least in CNX2 that I know of) is that once you've dragged the curves into the extreme opposite end of what would otherwise constitute normal processing, the slider for contrast needs to be set to -100, that is absolutely zero contrast. And you should have an almost nicely set print of the neg.
The contrast setting makes sense in a way, and it all comes down to the reversal process again ... something I've never been exposed too.

I've now set this into CNX2 as a batch file which I'll use on the other negs. But I then thought that this may be cool to add as a Picture Control to upload directly into the camera, via the Picture Control editing tool. But I got stuck again. While the Picture Control editor has the required curves adjusting tool, it doesn't have the required de-contrasting control, that is to set the image to what would otherwise be a totally grey image.
If anyone with either Picture Control editing experience or how to setup a curves adjustment and import it into Picture Control Utility knows of any way to do this and reply .. that'd be great.

For now, here's the first export of the first test shot fro the roll of film and also from the capture of it on the slide copy attachment:
Rollei 35 40mm at f/4
84697

Here's the digital comparative:
D300 Tamron 28mm at f/4
84698

Here's the scan of the neg that I got from the print lab too.
84699

Exposures of the neg are different due to both capture onto the camera and also editing. To recover some highlight detail I set +1Ev on the raw file, but of course this means losing some mid tones in the process.

More tweaking to come in due time.