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Introduction The test wedge prints have been made accurately and in a reproduceable manner so that comparisons are meaningful and these methods are detailed below. They should not be taken as definitive since the nature of photographic processing means that every printer will produce slightly different results. As more samples are tested they will be included. Background The whole exercise grew out of my frustration in trying to make sense of the various papers that are available today (2009). As one favourite paper disappeared from the market I was forced to experiment to see what could replace it. For example, I was very fond of Agfa MCP, now unavailable, but I learnt that Tetenal TT Vario was "Agfa" just boxed up as Tetenal, so I bought up the remainder of stock at Tetenal UK. However when I next bought some Tetenal I found it had changed completely, despite still being called TT Vario. The only difference in the packaging seems to be that the old one was graded 0-5, whilst the later one 00-5. Of course, for anyone who has enquired, this tale will be familiar and wiser men nod sagely. Manufacturers too are frustratingly coy in not revealing who makes what for whom. I have spent hours searching websites and testing papers in an effort to cast some light on a muddled situation. I am not an expert - I am just a printer and I do not seek to be judged. Instead I would welcome positive contributions, both from other printers and from manufacturers who may wish to fill in the blanks or correct any errors I have made. All the information regarding emulsion and paper composition have been drawn from published material. The choice of test papers reflects what I have at hand in my darkroom and I would welcome a chance to test more if manufacturers wish to supply them. Alistair Baird |
| Process | Detail | Notes |
| Step Wedge | Kodak photographic step tablet no2 | . |
| Enlarger system | Contact printed; Ilford Multigrade 400 system | . |
| Test grade | 0 | To produce a wide tonal range with variable contrast papers |
| Exposure | f5.6, 10 seconds ( ADOX Classic gd3 30sec) | . |
| Developer | Ilford Multigrade 1+9 @ 20c 2mins | Papers will react differrently to other developer types |
| Fix | Ilford Hypam 1+9 @20c 4mins | Non hardening fix suitable for toning |
| Hypo reducer | Kodak Clearing Agent @20c 3mins | . |
| Wash | Nova Archival washer @20c 20mins | . |
| Bleach | Potassium Ferricyanide 50g, Potassium Bromide 50g in 1000mls water @ 30c 2 mins | Followed by 10 min wash |
| Thiocarbamide | Part A - 10% w/v Thiourea in water Part B - 10% w/v Sodium Hydroxide in water 30mls A + 30mls B in 500mls water @ 30c 1min |
Followed by 30 min wash |
| Selenium | Kodak Selenium at 1:15 dilution @30c 8mins | Followed by 30 min wash |
| Gold | Tetenal stock solution @30c 5mins | Followed by 30 min wash |
| Scanning | Epson 4990 A4 flatbed | . |