[APML] Provia 400F

[Matt BenDaniel <matt@starmatt.com>]

Although Fuji Provia 400F is not the perfect astro film, I have to admit that it has grown on me over the past couple of days. I've been testing many different curves for my M42 image. I think this really helps to understand what the film is doing.

I exposed a 90 minute, a 10 minute, and a 1 minute shot of M42 on 400F 120. I combined them using the same "masking with layers" method that Jerry has described so well.

1. Usually during masking with layers, one has to adjust the color balance of the component shots. In this case, no adjustment was required. All I did was scan and adjust the levels of the three shots consistently.

2. The anti-vignetting mask for this image uses shades of gray only. That is unusual. What I have seen with PPF and E200 is that they tend not only to darken off axis, but the background also changes its color balance off axis. The solution is an AV mask which varies in luminosity and color from the center out to the edges.

My tentative conclusion is that 400F has virtually no differential reciprocity failure, that is, all three emulsion layers fail at the same rate. I think 400F also has a very even color response overall. These characteristics make images on this film much easier to process than on other films.

I still think that 400F has less sensitivity to faint red nebulosity than E200 or hypered PPF. But I think 400F's faint red response is no worse than unhypered PPF's. 

http://people.ne.mediaone.net/mbendaniel1/gallery/astro/sword.html
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Matt BenDaniel
http://starmatt.com


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