In a hybrid workflow, that is: shooting the pictures on film, developing and then scanning the negatives, it is imperative to get the most from your negatives in the scanning step. To achieve optimal flatness of the film, and therefore sharpness, most people recommend a scanning setup in which the negatives are hold down using a glass plate. To prevent unwanted rings on the image that arise from the contact of the negative with the smooth glass, you can use special glass that has a rough side, called anti Newton ring glass (ANR glass). In this post, I will show a comparison between a scan with and one without ANR glass on an Epson v550.
The film is Kodak Ektar 100 shot with a Hasselblad 500 C/M with a Carl Zeiss 80mm f/2.8 Planar CT* lens. It was then scanned on an Epson v550 with a standard film holder, with and without ANR glass to hold the film flat. The scans were made at 48 bits and processed with The Gimp (some more on that later).
No ANR glass: standard holder
The setup without the ANR glass looks like this:
The film is only hold flat by the holder.
Standard holder + ANR glass
The setup with the ANR glass looks like this:
The glass that is lying on top of the film flattens it. The rough side of the glass is in contact with the film to prevent Newton rings.
Click the image for a larger view. On the left is a 100% crop of the scan in which the ANR glass is used, on the right a scan without the ANR glass.
Although this is but a small, quick and dirty comparison, I think I won’t be using the ANR glass any more in the future. As seen from the 100% crop, it does not really lead to an increase in image sharpness, but it does add a lot of unwanted texture to the image. I presume this texture is caused by the rough surface of the glass which is used to prevent Newton rings. As the scan without the glass is sharp enough for my needs, I will continue scanning happily without the glass on top.
Please let me know what you think in the comments, and also let me know if you do have positive results using the ANR glass.
The final scan (without using ANR glass) is shown below.
Aftertought: the new Gimp 2.9!
The edits were made in the new development version of Gimp: version 2.9. It has some cool features, of which I particularly like the support for 48 bit images and the new split screen preview for most of the tools. Here is an example of this new split screen preview with the level tool:
Gimp is a great free tool for editing photos, and I am looking forward to all the new features that will come with this new version of Gimp!