Category Archives: equipment

Processing C41 colour film in black & white chemistry

Summary

I have had promising results developing colour print film in standard black & white chemicals. Not only is it identical to processing black & white film but the fine grain and wide exposure latitude of C41 colour film is preserved in a black & white negative.

35mm colour print film can still be obtained in most city high streets, at least in the UK, and provides an available and low-cost alternative to regular b&w negatives for those willing to process and digitise their film.

The test

I had some out-of-date 35mm C41 colour print film (Kodak GC-400, a cheap, consumer-level ISO400 film, no longer available) and wondered what would happen if I processed it in my normal black & white developer, Rodinal (actually ADOX Adonal, which is identical to the original AGFA formula), so I fired off a roll of the colour film followed by a roll of black & white film at the same ISO400 setting, which I processed in the same chemistry for comparison. I used the same development time for the C41 film as the Massive Dev Chart recommends for Ilford XP2 (a C41 b&w negative film), so if you want to use a different developer go ahead!

The C41 film was given 18 minutes at 20C in Rodinal diluted 1+25, 1 minute stop bath, 5 minutes fix.

Ilford HP5+ was given 6 minutes at 20C in Rodinal diluted 1+25, 1 minute stop bath, 5 minutes fix.

The films were scanned using the same scanner and software (Epson V750 and Vuescan). Vuescan was set to auto-expose and give 2 passes for each frame, which I’ve found significantly reduces noise. The levels were adjusted in Photoshop to give a full tonal range on the histogram but no other manipulation. Samples for comparison are shown below.

The results

Inspection of the films under a loupe showed that the colour negative had low contrast and a long tonal scale together with fine grain; this is consistent with expectations for standard C41 processing. The black & white film showed normal tonal range (it was a dull day when both films were shot) but more distinctive grain. Here are the scans from the 35mm frames. The cropped images are an identically-sized area (10 x 7mm) of the frame:

C41 film full frame

Kodak GC-400 colour film at ISO400 processed in black & white chemistry, full frame

HP5 full frame

Ilford HP5+ at ISO400 processed in same black & white chemistry, full frame

C41 film cropped to show grain structure

C41 film cropped to show grain structure

HP5 cropped to show grain structure

HP5 cropped to show grain structure

Conclusion

C41 colour film can be processed in standard black & white chemicals to good effect. Although only one film type has been tested it is reasonable to assume that other C41 films will respond in the same way as they are formulated for standard machine processing.

The wide tonal range and fine grain characteristics associated with colour print film is retained when processed in black & white chemistry, though only a black & white negative is obtained on the orange film base of the C41 film. This is excellent for scanning but is likely to be problematic for anyone wanting to darkroom-print onto gelatine-silver paper.

If you need b&w film urgently or want to use cheap film to give black & white negatives for scanning, C41 colour films like Kodak Color Plus (ISO200), Agfa Vista 400 or any film from the Fuji Superia range (ISO200 to ISO1600) should be a lower-cost alternative to black & white film, especially if you can get short-dated film over the Internet (short-dated colour film should still be fine for black & white work as any colour shifts over time are irrelevant).

If you want gritty grain, well-tested development times for push and pull processing, or the ability to darkroom print from the negative, it would be best to stick with black & white negative film.

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potential replacement for Polaroid type 55 pos/neg film

Polaroid 545 holder

You will need one of these film holders to use the proposed new pos/neg instant film

If you own a 5×4″ camera and Polaroid 545 back you will be interested to hear about a project to develop a replacement for the much-lamented black & white positive+negative film, type 55.

Bob Crowley in the USA is working on this and has a Kickstarter project to raise some capital. Do consider helping him out: https://www.kickstarter.com/projects/bobcrowley/new55-film

Better flash for iPhone 5/5s

Here’s neat idea for iPhone 5/5s photographers: a better flash! It also functions as a video light and an off-camera modelling light – sounds great. Check out Kickstarter project Lightstrap at http://kck.st/1cWQ0ML or their video: 


I’ve ordered mine! If you’re new to Kickstarter make sure you are comfortable with the risks before you commit your hard-won cash.

Hasselblad V dead – long live the Square!

Hasselblad may have announced the end of the line for its long-lived V system but we shouldn’t let the square image die!  Sales were dropping and digital is the way forward for most photographers but the cameras were well-made and should last for a long while yet, but what I most regret is the demise of another square-format image device.  Although there was a small-sensor (36mm square) back it didn’t last long, and Hasselblad conspicuously dropped its promotion of the square image when it launched it rectangular H series cameras.

So here’s my homage.  Not to Hasselblad V system but to the square image.  Let’s keep it alive.  And don’t let your Hasselblad V system Rest in Peace!

CocaCola. Mexico. Copyright Malcolm Raggett

CocaCola, Mexico. iPhone/Hipstamatic. Copyright Malcolm Raggett

Windmills. iPhone/Hipstamatic. Copyright Malcolm Raggett

Windmills. iPhone/Hipstamatic. Copyright Malcolm Raggett

Great Dixter

Square Gate. Cropped from 24×36 frame. Copyright Malcolm Raggett

Street Mexico

Two hats. iPhone/Hipstamatic. Copyright Malcolm Raggett

infrared film

Squares. Hasselblad & infrared film. Copyright Malcolm Raggett

near Great Fountain Geyser

Steam. Cropped from 24×36 format. Copyright Malcolm Raggett

infrared film

Stems. Hasselblad negative. Copyright Malcolm Raggett

120 film in Hasselblad 220 magazine

There is a steady trickle of well-used but serviceable Hasselblad V-series camera   components coming on the market at sometimes bargain prices (well, by Hasselblad standards, anyway).  This is great if, like me, you like to use black & white film occasionally.

220 film backs are particularly good value compared with the 120  magazines. Of course, the trouble is that no B&W film maker produces 220-size rolls any more.

Many people don’t realise that it is possible to use 220 backs with 120 film; the film registers in the same film plane no matter what film you use and the difference in pressure from the pressure plate seems to have no practical effect on film flatness or transport.  The frame spacing is different, each frame having more space between it and the next frame in the 220 back. It isn’t a huge difference but you can lose the 12th frame if you don’t compensate. Here’s how: when loading the film, stop when the arrow is as shown in the photo:

loading 120 film in 220 back

Miss-align the arrows as shown when loading 120 film into a 220 Hasselblad back (this probably applies to other makes of film back too)

The 220 film magazine will wind beyond the 12th frame so with 120 film you will be exposing on the the protective paper – oops! You just need to watch the frame counter – when you have exposed the 12th frame, cock the camera to frame 13 then wind on the film fully using the winder on the film back.

Voila – there’s still life in those 220 film backs!

Leaf Aptus II 12 and Anagramm Production2 comparison

I don’t normally write about equipment in this blog but I’m making an exception in the hope that someone might find this interesting.

I recently compared the 80Mpx Leaf Aptus II 12 single-shot digital medium format back and the 312Mpx Anagramm Production2 5 x 4 inch scanning back. My employer has owned an Anagramm Production2 scanning back for several years. This has a resolution of 13,000 x 8,000 pixels and is used for digitising larger books, maps and artwork from our collections. (Each pixel records R, G & B colours hence the 13 x 8 x 3 Mpx count). We currently use Phase One P45+ backs (7,216 x 5,412px, i.e. 39Mpx) to digitise smaller items. Leaf recently released a back of 10,320 x 7,752 px, i.e. 80Mpx, and I recently spent an afternoon evaluating the Leaf back against the Anagramm. I was impressed by the quality of the Leaf to the point where I would advise anyone looking to invest in a scanning back to seriously consider the new 80Mpx backs from Leaf (since Phase One are releasing an 80Mpx back based on the same chip, this would also be worth evaluating, though the additional sophistication of the Phase One back will be largely wasted on the digitisation applications I am mostly involved with). In the time available I could only evaluate the fidelity of resolution, not colour. I used the same camera and lens, column stand, lights and original artwork, which ranged in size from roughly A4 to A3. The camera was a Linhof RD-1 with 180mm f5.6 lens. This lens had a built-in infra-red filter though this was only necessary for the Anagramm scanning back, since the Leaf has an infra-red blocking glass as part of its construction. It was necessary to adjust and re-focus the camera for each image and, since the Leaf has a much smaller sensor area than the Production2, I was more restricted on the size of original I could copy with the Leaf. I cropped much more tightly with the Leaf than the Anagramm, which had the effect that 100% enlargements were about the same size from both backs.

I chose 3 Japanese woodblock prints from our collections. These had a lot of detail right down to the paper grain and the inker’s wiping marks, so these should be a good test. All test shots were exposed so that the brightest highlight fell substantially under the 255 saturation point. The dynamic range of all medium and large format backs is well able to cope with the reproduction of the works of art we normally digitise, though I made sure I included an item with reflective gold on it just to make sure the Leaf could rise to this challenge (it did, with ease). I also white balanced all images against a Qpatch included in each shot. The Leaf back was set to its native ISO50 setting. The Anagramm back is not calibrated to ISO film speeds: instead I set the scan speed to Fast (1 notch down from Very Fast) and the fine control, or amplification, came out at 96% to achieve good exposure. I used well-ballasted continuous lighting for the tests. The ballasting reduces flicker, which is significant when the Anagramm back is scanning on fast and very fast settings. The ballasting won’t be of practical significance for the Leaf back.

So here are some results, full frame image and 100% enlargement:

Anagramm Production2, Linhof RD-1, Symmar 180mm f5.6 at f8. Grey balance applied

Leaf Aptus II 12, Linhof RD-1, Symmar 180mm f5.6 at f8. Grey balance applied

Anagramm Production2, Linhof RD-1, Symmar 180mm f5.6 at f8. Grey balance applied

Leaf Aptus II 12, Linhof RD-1, Symmar 180mm f5.6 at f8. Grey balance applied

Anagramm Production2, Linhof RD-1, Symmar 180mm f5.6 at f8. Grey balance applied

Leaf Aptus II 12, Linhof RD-1, Symmar 180mm f5.6 at f8. Grey balance applied

The results amazed me when I saw them side by side on the monitor: I had previously seen a significant difference between the 39Mp back and the Production2 back, but this time the ability of the 80Mpx Leaf and the 312Mpx Anagramm backs to distinguish detail was very similar. No sharpening was applied to the images, however the process of down-resolving to create the above JPEGs has reduced the quality noticably. Remember that the backs were not colour-profiled so you cannot judge the colour quality in this test.

Timings

I timed the process of composing, focusing, setting exposure and white balance and capturing the image. Both Anagramm and Leaf took 4 minutes 30 seconds. If subsequent images could be taken without further adjustment, the scan time of the Anagramm was a minute whereas the shutter speed for the Leaf was 1/30th of a second. So from a production point-of-view the Leaf would win hands down – this productivity is worth a lot of money. In practice we use Mamiya cameras with P45+ backs for their speed. We find that we can digitise 5 times as much material with the P45+ compared to the Production2, so we reserve the Production2 for large items such as maps. The Leaf Aptus II 12 and the Production2 both have a “live view” refreshed at several frames per second, which makes focusing so much easier and safer than using the Mamiya’s viewfinder a long way up a column stand – another reason to trade up to the Leaf, but this time from the P45+.

Conclusions

There is a tendancy for digital copying processes to enhance the contrast of the image in comparison to the original, and the Leaf did just that. Although a custom ICC profile would help (I will do this if I can get my hands on the back for a bit longer), it is still necessary to adjust the final image, from whatever source, manually alongside the original to get the ultimate fidelity to the original. I don’t normally have the budget to do this so it is important to me that the calibrated workflow gets as close as possible to the original without manual adjustment. The indication from my testing so far is that the Leaf will do an excellent job. The Leaf seems to come so close in quality to the Production2, with the advantage of speed and smaller file size, that it is hard to see the justification for the 312Mpx scanning back.

The quality achievable from high megapixel cameras needs scrupulous attention to detail in lens quality, rigidity of support and quality of lighting. Accurate focusing is also essential. But get these right and the Leaf Aptus II 12 can produce exceptional results.

Credits

My thanks go to Andy Quiney of Peartree Rental Ltd., and Yair Shahar, Product Manager at Leaf Imaging Ltd For their time, interest and equipment in making this test possible. The School of Oriental and African Studies provided its digitisation facility and equipment for the test.