Here are a few soundbites in response to FAQs unasked:
• What’s the best enlarger lens for general taking at sub-1m distance?
Of the growing number of lenses thus far tested outstanding results have (unsurprisingly) been recorded by the most expensive lenses. However, several lenses with market values of around £100 have achieved an elite 90%+ rating for average resolution across the frame at working apertures. For further details, please read the full reviews on the archive page, and refer to the Near-Distance tables in the Hall of Fame.
• What’s the best enlarger lens for general taking at 10m+ distance?
Nikkor EL-N models sustain performance very well at long distance, and render comparably to conventional taking lenses. They have proven to be not just the best value in this survey, but arguably the best lenses for such applications full stop. Bokeh issues make Rodagons better taking lenses than Componon-S. The highest graded lenses so for tested for distance resolution at working apertures are the Nikkor EL 80/5.6 N and Rodenstock Apo Rodagon 105/4 N, which jointly score 88.5%. Note that the close-up pack-leading Meogon 80/2.8 only scores 80.5% at longer range. For further details, please read the full reviews on the archive page, and refer to the Far-Distance tables in the Hall of Fame.
• Which Delta lens has the best bokeh?
Unanswerable. If we define ‘best’ as ‘smoothest and least intrusive, without onion ring or soap bubble highlights’, modern taking lenses have all such ‘character’ dialled out. For some, that’s a problem. However, the array of fast slide and cine projector lenses available generate all flavours of bokeh. The full spectrum of diaphragm possibilities is represented in the Delta archive: from slits to circles. Personal, uncontroversial favourites include Isco / Schneider cine lenses, Agfa Color-Solagon enlarging lenses and Leica Colorplan slide projector lenses, but you may also like the wickedly contorted bokeh of the Bell and Howell 16mm lenses deployed on M43 or the perversely agitated bokeh of late model Pentagon-of-Evil Schneider Componons. It’s all there to explore.
• Can I get a good sunstar from an enlarger lens?
Yes. Top marks goes to the Fujinon EX range: eight straight blades isn’t always a recipe for success, but Fujinon sunstars are almost as pretty as those drawn by a good Voigtlander. Minolta’s CE range gives tidy stars, too. The Nikkor EL’s are commendable for delivering serviceable stars from f8. Rodenstock’s Apo Rodagons should also be singled out for refusing to decorate specular highlights with anything so gaudy as a star. Stop down their curved five-blade aperture all day and you see only discs.
• Which enlarger lenses would you not recommend for taking?
None of the modern Schneiders with convex pentagonal apertures if any part of your image is out of focus. The four-element Nikkor EL 75mm f4 is not comparable to the 80mm f5.6, but in some markets cost about the same. If per-pixel sharpness matters, none of the standard Rodagons and Componons (or their inferior predecessors and juniors, junigors, junigonars, and junigonandons) are well optimised for longer-range work. The Focotar II is too expensive, given its mediocre long-range performance. And unless you’re seeking a really old-school look, avoid the weakest four-element lenses and all triplets – some of which have the dreaded/lauded swirly bokeh.
• Is Delta a ranking system for enlarging and projection lenses?
Yes and no. Our in-house tests rank lenses on an inappropriate, but level, playing-field. Some test metrics have no bearing on how a lens performed in its intended application: for instance, bokeh is a relevant consideration in a taking lens; not in a projector lens. Enlarging and process lenses have no business being pointed at distant objects wide open; therefore low scores in this category are no slight on their reputation. However, certain evaluations – particularly the near-field f5.6-8 sharpness average – were intended to mimic the native (albeit inverted) use-case of enlarger lenses. As the number of reviews grew, it become clear that Delta provides a reliable index for ranking the optical excellence of enlarger lenses – particularly below 60mm. The Hall of Fame for wide open performance at distance is probably the best available league table of projector lens excellence. However, Delta’s bias toward digital capture on 35mm creates two blind spots that impair its ability to judge enlarger lenses for their intended purpose:
1. Not every lens above 75mm is tested for Zone 4 sharpness, which is critical to enlargement of medium format negatives. Therefore a lens Delta recommends in the 80-105mm range on the basis of the central 43mm portion of its image circle may have considerable fall-off visible when used on larger format sensors, or – when used an enlarging lens – that compromises corner sharpness.
2. Low contrast and vignetting are cardinal sins for an enlarger lens, but minor misdemeanours as a digital taking lens due to the ease of correction in post-production. For video capture (even full-frame) Zone 3 vignetting is cropped out as the sensor mattes to 16:9 or wider. In this area, Delta is blatantly not an evaluation system for print-makers.
However, Delta’s ranking system uniquely enables a scanner lens, a cine projector lens, a slide projector lens and an enlarger lens to be directly compared and quantified as taking optics for 35mm and smaller sensors.