Friday, December 18, 2015

Anti-Newton Ring Glass and Scanning Negatives

This has been one of the things I've been researching for some time. During my years at London College of Fashion, I had access to many great tools for photography, including 4x5 large format cameras, Tetenal C-41 dip and dunk tanks processing room and many more . . . However the tool I miss the most and want to have one here on my desk but can't afford is Hasselblad Flextight X1 drum scanner (Virtual Drum Scanner). Works like a drum scanner but technically not a drum scanner. Thanks for the info Ben

Because of my limited budget I could only spend about £500 which was more than enough for the next best thing which is Epson Perfection V750 Pro. The difference between these two scanners besides the £9000 price gap is that the Epson is flatbed scanner optimised for film scanning and the Hasselblad scanner is drum scanner (virtual drum scanner) only made for film scanning. 

Since I used Hasselblad scanner about 3 years and purchased my own Epson after my graduation, I noticed that Epson isn't giving me the best image quality when compared to Hasselblad. However in my research I found many ways of optimising the quality of epson, one of which is ANR(anti newton ring) glass. 

So the research I did is not only reading web forums or comments and etc. I actually take it to testing level to see why images are not as sharp as they could be, which was bit obvious. The negatives in the Epson Scanner or any flatbed scanner is arching and in Hasselblad X1 scanner all the arching is controlled and minimal compared to flatbed scanners. 

The Hasselblad X1 is holding the negatives in thin flexible metal plates which the centre area is cut open like a window and the negatives are held there with thin flexible magnets which again the centre part is open, this gives a firm grip on the negative and not allowing the negative arch in a unwanted way. In the process of scanning X1 takes the film tray in and bends it in a way it gets all the unwanted arching, furthermore the lens inside the scanner can focus on the negative, where the flatbed scanners have a fixed focal length. 
Another thing to note is X1 has better optics however the biggest factor of this is the autofocusing and glass free optical scan (No glass between the lens and film) 

So now that we know why the images from X1 have the edge in quality, how can we maximise the quality of Epson V750 scans?
The best thing we can do is prevent the negative from Arching/Curving. So the use of ANR glass plays a good role in here as the diagram below demonstrates. 


Is ANR glass always necessary? Because after all you are putting another piece of glass on top of your negative? 
I'd say it certainly prevents the negatives from arching while they are in the scanner, but if the negative is already straight to begin with and will stay straight in the scanner as well, then there is very little to notice. 

Before buying the ANR glass I looked in to why do negatives arch and can I prevent it? 
So in this search I came to conclusion that:
  • All negatives arch when exposed to heath "heath is a factor"
  • Not all negatives have that "natural arch" 
The heath:
For those who don't know me. I'm like a polar bear, I like cold and I don't turn the heating on in winter and currently the house is just under 18ÂșC(18.12.2015) So in winter the heath is not a big factor for me, however when I put any negative on top of my hot Laptop I can see the negative arching right in front of me. AND! the CCFL lighting in the scanner do tend to get warmer, so more film scanned warmer the scanner will get, this can result the negative curving or arching in the scanner tray. This is where ANR glass can be helpful. 

Naturally arched ?? Is this real?? 
So I looked at two black and white negatives I processed at home. Fomapan 400ISO and Ilford FP4+ 125ISO
I don't know why Fomapan negatives processed in the same way as Ilford started to arch and why Ilford stayed flat? maybe its because it's the most affordable BW film In the market who knows. But some films do tend to arch naturally, so Having a ANR glass will not be bad decision, its like you will be prepared for anything.

Below I show 2 cuts of 120 film shot in Mamiya RZ67 ProII and processed in HC-110 and Ilford Hypam Fixer. 


What about scans? 
I'll show the scans from Ilford, with and without the ANR glass to demonstrate ANR glass. However as I said before if the negatives do not arch in the scanner or by them self it becomes very hard to notice. 


With ANR Glass and Sharpening in Scanner(below)



Without ANR Glass and Sharpening in Scanner(below)



With ANR Glass No Sharpening in Scanner(below)



Without ANR Glass No Sharpening in Scanner(below)




So is ANR Glass 100% necessary? 
Not unless your film arches. As I'll do more scans in variedly of negative, Colour negative and colour transparency film I'll let you know, but I know that Arched film is really problematic when scanning and having ANR glass is handy if you are dealing with that problem, so I'd recommend you to have it just to be safe and/or if your profession is photography. 

Again I will make more post about this as I come across arched negative in future, its just a matter of time.

2 comments:

  1. Hey Bruce,
    Sorry not got that film out yet, super busy.

    Not to be too picky but the Imacon / Hassablads are not technically drum scanners. They use a system that imitates them but lack two elements that make drum scanners amazing, PMT's and anb apature - that said i've pulled great scans off an X1 in my time.
    I only say this I own and operate a real drum scanner (www.analoguse-arts.com). If you've got any killer negs you want scanning drop me a line.

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    1. Thanks for informing Ben. Happy NewYear by the way =)
      Interesting that places like BH photo that sells it says its drum scanner and others refer to it as "virtual drum scanner" whatever that means. I called it drum scanner because the technician at LCF who teach me to use it called it drum scanner, but knowing that your knowledge dwarfs mine in comparison and you work with these things, you are probably right. So what should I call good ol Hassie here "drum scanner wanna be", "virtual drum scanner" ???

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