Sunday 14 April 2019

Using the Behringer Model D as a Filter


A while back I had a look at the Behringer Model D. It's a modern-day analogue synthesiser that emulates the venerable Moog MiniMoog. I've never used a MiniMoog, so I can't compare them myself, but the internet believes that the Model D is the musical spitting image of the original and so does this chap from Sound on Sound magazine. As an instrument in its own right I enjoy it immensely although it's not as flexible a synthesiser as the Korg ARP Odyssey (for example).

Physically it feels cheap but original MiniMoogs are now so expensive on the used market that they're almost unusable in a live context. What if you spill beer on your MiniMoog? What if it gets stolen? You would have to destroy roughly twelve Model Ds before the cost equals a single MiniMoog.

One of the MiniMoog's best features is the filter, which has a distinctively "smooth" sound. It's hard to describe in words but it has a smooth, rich, full-bodied sound. The MiniMoog has an audio input that can feed external sounds into the filter, and so does the Model D, so I decided to try it out:

This video also contains some remarkably clear footage of my right hand.

In this video the Model D's oscillators are turned off. Instead I'm feeding the sound of a Korg MicroKorg into the filter. Ordinarily this would result in silence, because you need some way to trigger the Model D's envelopes - there isn't a way to just disconnect the envelopes or force them to be always-on.

Therefore I'm using the gate output of my Arturia Beatstep as a gate source. To complicate matters the Model D has separate gate inputs for the loudness and filter envelopes, so I have to use a stacked splitter cable to trigger both of them. Notice how the cable running into the LC GATE input - above and to the right of the FILTER EMPHASIS control - has a second cable coming out of it, leading into the FC GATE input.

The BeatStep is feeding notes into the MicroKorg via MIDI, and the end result is a Korg MicroKorg with a Model D filter, or alternatively a Model D with a MicroKorg's oscillators. Ironically the MicroKorg has a bunch of analogue-sounding presets, so the end result still sounds like an analogue synthesiser. It would be fascinating to put a Yamaha DX7 or something obviously sampled through the Model D instead. That is for the future.


Let's take a moment to reflect on the unlikely renaissance of analogue synthesisers. Actual genuine analogue synthesisers with analogue circuitry, not software emulation. Few people in the 1990s would have guessed that CV/GATE would make a comeback in the new millennium, but here we are, with no less than two analogue recreations of the ARP Odyssey on the market, plus a bunch of affordable compact keyboard synths from Korg. Even Arturia, who make software instruments, now sell an analogue synthesiser.

Also, I have learned to spell millennium correctly. That's not much use in 2019, but who knows. Perhaps Chris Carter's Millennium will make a comeback and I will find myself needing to write about it. There's an easy way to remember how to spell millennium. It's like accommodate. It goes two-two. Two-two.

Philippines is one-two, Mississippi is two-two-two, but millennium and accommodate are two-two.


Two-two.

Vivitar 28-90mm f/2.8-3.5 Series 1


The boat. It is on the building. That is the USS Constitution, and today we're going to have a look at the Vivitar 28-90mm f/2.8-3.5 Series 1. It's a fast-ish wide-ish-to-telephoto-ish general-purpose zoom from the 1980s, I guess, perhaps the late 1970s. It pops up in magazine price lists in the 1980s so I'm going with the early-to-mid 1980s.



I recently took it to Italy to let it look at the sunshine one last time, before putting it in a cupboard forevermore. All the images in this post were shot with the 28-90mm on a Canon T70 using a load of Fuji Superia I have lying about.

Apertura is the Italian word for "opening". It's also the Spanish and Catalan word for opening as well, because they all borrowed it from the original Latin. You know more Latin than you know.

I've used a tonne of old lenses over the years and I always wonder what they did when they were alive. There's a little subgenre of films that follow the history of an object; The Red Violin, the BBC's recent Gun No. 6, and I should really find more than two examples. Raiders of the Lost Ark? Lord of the Rings?

One thing linking those films, and reality, is that the artefact - whether a violin or the Ark of the Covenant - has two lives. At first it's used for its original purpose by the original creators, and then it has an afterlife during which it becomes an object of veneration. It becomes too valuable or obsolete to use in anger, so it gets put behind glass in a museum or buried in the desert or lost.


Forty years ago, when my 28-90mm was new, it was probably bought by a well-off middle class person who wanted to take photographs of his wife on holiday in Spain, or perhaps Hong Kong or somewhere further afield. For a few split-seconds spread over a few years it captured the light of foreign lands, and then for the next three decades it was put in a desk drawer or cupboard. Forty years later I gave it new life. Probably for the last time, unless this blog post explodes in popularity. It's still in good shape, but I imagine that the glass will eventually develop fungus, at which point it will become a paperweight.

Or I could use it to weigh down a bag of rabbits, so that they sink. Why rabbits? Pour encourager les autres.

Shown here on a Canon T70. In the last few posts I've had a look at Canon's FD system. Canon didn't have a direct equivalent of the 28-90mm; the Canon 28-85mm f/4 and 35-70mm f/2.8-3.5 were slower or not as wide. Professional-level fast standard zooms didn't really take off until the late 1980s, and even then 28mm was as wide as you got until the mid-late 1990s.

I've written about Vivitar's Series 1 range before. It was Vivitar's range of posh lenses. At first the company oversaw the optical designs, or at least came up with a specification, but they were all constructed by OEM manufacturers in the Far East. By the mid-1980s Vivitar gave up on original optical designs and simply picked OEM lenses that had promise and put a Vivitar badge on them.

As far as I can tell the 28-90mm is a rebranded OEM product. The 28 dot dot serial number means that it was originally made by Komine, Very little is known about Komine. The company was founded in the immediate post-war years by a chap called Manjiro Komine. It was headquartered in Tokyo and went bankrupt in the late 1980s. For a while it was suspected that they didn't even exist, and that the name was a mistranslation or misprint of Kominar, but apparently they did. Somewhere in Japan there are a handful of people who know the answer to this, and perhaps there's an obscure Japanese blog made by the relatives of Mr Komine, but alas we may never meet.

The history of OEM Japanese lenses from the 1960s is fascinating. Mildly fascinating. Slightly fascinating. Nowadays eBay and Alibaba sell products from a tonne of small businesses in China that make powered USB hubs, generic mobile phones, bluetooth keyboards etc - a huge and largely unregulated melting pot of companies that come and go. The Japanese camera industry in the 1960s wasn't quite so anarchic (it took capital and plant to make lenses) but it was close.

Wide open the 28-90mm is sharper than the 200mm f/3, but it suffers from purple fringing on high-contrast edges.

Lurking at the back of my big shelf of lenses I have another Vivitar zoom, a Vivitar 28-85mm f/2.8-3.8. It was made by Kino and was sold by Vivitar at the same time as the 28-90mm. It has a very similar physical design. It's the lens at the bottom:

This picture also illustrates the glossy black finish that was typical of Series 1 lenses.


The two lenses are push-pull-twist designs with a wide front end. The specifications are similar and they both focus closely until the last 10mm or so, at which point the minimum focus distance goes up considerably. The coatings are different. My hunch is that either lens could have been a Series 1 lens, but Vivitar flipped a coin and picked the Komine lens, perhaps because it was slightly cheaper to source. Who knows.


Optically I can't test the 28-90mm because it's an FD lens. On a Canon EOS camera with a standard non-optical FD-EOS adapter it won't focus to infinity; at 90mm the maximum focus distance is about two feet and at 28mm the front element almost touches the subject.

Shot at about 50mm with a Canon FD-EOS adapter. There's a lot of blue-yellow CA visible on the number 6, which might be the fault of the adapter, so I'm not going to hold that against the lens.

My impression is that the 28-85mm is slightly better than the Series 1 28-90mm. The 28-90mm's big problem is vignetting. It has lots of it, although admittedly it's mostly confined to the extreme corners. It's difficult to correct because the drop-off is very sharp. Stopped down it goes away but it's a bother wide open. My hunch is that back in the 1980s it wouldn't have been so much of an issue - the edges of slides were always hidden by the mount, and prints were regularly cropped - but in the modern age it's annoying.


Here's an example of a shot that looks pretty poor with the vignetting but much better with the edges cropped off:


On the internet the 28-90mm has a good reputation, but most of the reviews I have read are from people who have used it on a crop-sensor digital camera, in which case the vignetting is cropped away naturally. Take away the vignetting and it's not bad - looking at my film scans there's a bit of blue-yellow CA, with noticeable but easily correctable barrel distortion at 28mm and very mild pincushion at 90mm, good central sharpness at all focal lengths.

On the other hand the 28-85mm doesn't have the same vignetting and if you have a choice between the two it's slightly better. I think of them as 35-80mm f/4 lenses that have been widened out and made faster for convenience rather than optical purity.



Physically both lenses are heavy, made of metal. After forty years they both have zoom creep, so I tended to use the 28-90mm at 28mm or 90mm but not in the middle. The loose twisty-turny-pully interface probably isn't much fun if you want to shoot video with a mirrorless camera.

I'm naturally averse to pointing lenses into the sun but apart from a generalised loss of contrast as visible above the contra-sun images I took had surprisingly decent flare control for an ancient zoom with a big front element. If anything the flare control is slightly disappointing - videographers tend to be drawn to vintage lenses because they have masses of flare and washout, not because they are objectively fantastic.

This set of photographs was taken on the disused banked track at Monza on a dull day. You can't do a complete circuit any more because parts are blocked off, but people ride their bikes on it.







If you're after a compact travel kit for your FD camera you could probably get away with a 28mm or 35mm and lots of walking back and forth. Colour-wise the 28-90mm is a bit muted, a bit "gritty", but not offensively so. The other Series 1 lenses I've used also had muted colour, so I can't tell if it's a Series 1 thing, a 1970s thing, an expired film thing, or if I just happened to shoot on dull days. Here in the UK we have lots of dull days.