Old Sigma 16mm focus confirm

[David Kilpatrick]

Back when only using the A700, I had an 8mm Peleng which 'went bad' (impossible to focus) and got thrown away eventually, but one shot with it secured the front cover of our town's Ordnance Survey map and the fisheye views on Alamy keep getting zooms (means people look at them more than other views). I can't justify a new Sigma 15mm or Sony 16mm, and the Russian 16mm is about £150 - not that I would now trust it for focusing. I was looking at the secondhand M-AF stock of Ffordes, one of the better UK dealers with a used stock website, and found an acceptable condition Sigma Filtermatic 16mm f2.8 'Focus Aid and Programmable' lens for £89. This is almost as old as the M-AF mount, I guess it would be 1987-90. At that price, with focus confirmation, had to get it.

Here's the result at f/11:



http://www.pbase.com/davidkilpatrick/image/109072524 for full size A900 image

At f2.8 it is very sharp indeed over the centre circle of maybe 30mm diameter, and very soft beyond this, though there is a sharp core to the image. f4 shows only a minor improvement, at f5.6 the edges are still fairly soft, by f8 it would be usable for most subjects, f11 is almost there and still very sharp centrally, f16 really improves the edges (they become properly sharp to the corners) but loses a little centre sharpness, f22 is more even across the frame and is actually usable.

Here is an f/22 shot taken at the minimum 6 inch/15cm focusing distance - and they mean the film plane, too, the winter aconite is maybe only 2-3 inches from the front glass:



http://www.pbase.com/davidkilpatrick/image/109072768

The flare resistance is not bad for a lens which can be taken apart and has a 22.5mm plain UV filter screwed into the centre. You can bayonet the entire front group off the lens front, and swap the filter, but this example did not come with a case, or with its original front cap, or filters. Because it has this internal filter, it would be possible to fit an infra-red gel, and the lens focusing scale also has the IR position marked. Here is a direct into the sun shot showing the extent of reflections and flare patches:



The whole lens is very well constructed, solid metal, with a top quality bayonet mount, five-contact communication, and it does work with focus confirmation on the A900. The camera displays MF when the lens is mounted, and the focus confirmation light works (presumably the centre f2.8 sensor gets used, but there's a fair amount of tolerance). The Sigma 24mm f2.8 Focus Aid lens from the same period has a very good reputation, and should also work.

The lens size is comparable to the Sony, maybe slightly smaller, rather than to moden Sigma alternatives, and it makes a great low-cost addition to my outfit just to secure the fisheye rendering. I do not think that it is clean enough at the edges to do a de-fisheye operation on it, even at f16. On APS-C it would not be much use but the entire image area would be very sharp.

David

[ianmiddy]

So it was you who bought it ! - been looking at it since xmas spending started, hoping it would remain, but noticed it'd gone when I was looking over the weekend - might have beaten you to it if the car hadn't cost me as much & a lot more a week or so ago...

...oh well, will have to stick with my old 0.42x F/E converter from 25+yrs ago - I don't doubt you'll get far more use out of it than I would have.

Cheers

IDM

[PS - Ffordes seem to have got rid of quite a lot of the MAF mount stuff over the past few weeks - not sure if they've just junked some of the really old ones...]

[braeside]

The Sigma 24mm f2.8 Focus Aid lens from the same period has a very good reputation, and should also work.

Yes indeed I have one of those and it does work on the A900. Quite a bit of compound distortion though.

[David Kilpatrick]

Had a chance to do a few more shots - it does cut the corners off, just visibly.



http://www.pbase.com/davidkilpatrick/image/109076039

I saw the lens there a while back - before Christmas I think - but it was only when I saw the asking price for the new Russian lenses, without focus confirm, that I decided to go back and check it out. I'm surprised at such a low price (for a lens of that type) it was still there.

David

[01af]

... found an acceptable-condition Sigma Filtermatic 16 mm f/2.8 'Focus Aid and Programmable' lens for £89. This is almost as old as the M-AF mount, I guess it would be 1987-90. [...] You can bayonet the entire front group off the lens front, and swap the filter ...

I have the same Sigma Filtermatic 16 mm lens but for Minolta SR mount. It seems it was manufactured in the early '80s.I got it from eBay for a song in near-mint condition a few years ago, and it came with a soft pouch and a set of three 22.5 mm filters; yellow Y52, orange O56, and red R60 (plus the neutral NORMAL filter installed in the lens). I planned to use it for IR work (with the R60 filter) but at the same time my preferred IR film, Konica IR 750, was discontinued. So I hardly ever used that lens. Until now, I wasn't aware Sigma also offered this lens as a 'focus-confirm' lens for Minolta A mount ...

-- Olaf

[pakodominguez]

I was in the mood for a Fisheye too, and shopping for an unexpensive solution. I got this Accura 12mm f8 (to f16) for about 60 US$ on eBay. The seller only said, on the description, that the lens was a Minolta MC mount. I though I could modified the mount. Searching more about this lens (I found a couple more under different brands) I found it was a T-mount lens and it was selling for 4 times the price I paid for!

I haven't used it with the A900 (I havent borrowed it in a while) but on a X700 and the A700:
ASA 400 1/3 f11 converted from cRAW on Lightroom CA correction -30 / -30

ASA 400 1/4 f11 converted from cRAW on Lightroom CA correction -30 / -30

I shot this images while coming back home last Saturday after a gig near Times Square, at 2:10 AM and 24 Fahrenheit/-4 Celsius... A couple of tests I did at home showed that I'll get far better result exposing to the right. I'll playing more with this lens when the weather became more clement.

[David Kilpatrick]

... found an acceptable-condition Sigma Filtermatic 16 mm f/2.8 'Focus Aid and Programmable' lens for £89. This is almost as old as the M-AF mount, I guess it would be 1987-90. [...] You can bayonet the entire front group off the lens front, and swap the filter ...

I have the same Sigma Filtermatic 16 mm lens but for Minolta SR mount. It seems it was manufactured in the early '80s.I got it from eBay for a song in near-mint condition a few years ago, and it came with a soft pouch and a set of three 22.5 mm filters; yellow Y52, orange O56, and red R60 (plus the neutral NORMAL filter installed in the lens). I planned to use it for IR work (with the R60 filter) but at the same time my preferred IR film, Konica IR 750, was discontinued. So I hardly ever used that lens. Until now, I wasn't aware Sigma also offered this lens as a 'focus-confirm' lens for Minolta A mount ...

-- Olaf

Olaf, you may be interested to know that my business was responsible for IR750 being available in Europe. It was a special order item only, and I took a risk, and order several thousand rolls, which we sold through our magazines. Konica then decided to make it available the next year on general sale. I guess we did this around 1985. We had 120 rollfilm, as well as 35mm. I also organised the rebranding of Konica colour neg film for the National Trust in the UK - the next year, 3M offered them a better deal, for an inferior film. We also did all the tests shoots for Ilford, who bought in Konica films and rebranded them as Ilfocolor and Ilfochrome.

It's very odd that we worked closely with Konica - we gave away 10,000 Ilford Konica films as a promotion sending two free rolls to every Minolta Club member in 1984. Then, years later, Konica took over Minolta.\

David