Best focal reducer for wide angle lenses?

[glaebhoerl]

Or more like, "are there any focal reducers which are pretty good for wide-angle lenses and don't cost an arm and a leg?"

The drawback of a crop sensor (APS-C in my case) camera of course is that they make legacy wide-angle lenses much less wide. It's hard to go wider than around 30mm equivalent without a big lens and/or a lot of money.

This seems like the problem focal reducers should be intended to solve, but I've read mixed reports of their performance with actual wide-angle lenses, most people seem to be more interested in tele and/or large-aperture lenses for some reason. (It is my considered opinion that attaching a focal reducer to a telephoto lens makes about as much sense as putting a teleconverter on a wide-angle lens.) So I'm wondering if anyone has had a good experience using one of them for this purpose.

It's unlikely I'd be willing to pay for a Speed Booster Ultra, which costs as much as a new camera, but I might consider one of the less expensive options if it works well. In particular I'm curious about the Kipon Baveyes, which allegedly has the largest reduction ratio (0.7x, versus 0.71x for the Speed Boosters and 0.72x for the Lens Turbos), but information about them is especially scarce.

(The main alternative is probably to get a native 12/2 Samyang instead... but a focal reducer seems more fun, because then I can experiment with many lenses instead of just one.)

[buerokratiehasser]

I have WCLs from Sony and Olympus (0.7x, 0.8x)

They are well regarded and didn't cost me an arm and a leg. But that's because I am cheap. Never got around seriously testing them, they don't fit any lens without proper stepdown (58 mm, 62 mm IIRC)

If you only need to get under 30mm eq then, the usual kit lens (18-55) isn't to your tastes?

There is the Soligor/Vivitar/Voigtlander whatever

19-35 that people bid unreasonably high on. I suppose this is because it is a FF lens.

[glaebhoerl]

Yeah I don't like the kit lens. Used it once or twice and it just wasn't very enjoyable to use. I much prefer mechanical manual lenses.

I actually didn't even think of front-attached wide converters (I assume that's what you're talking about?). Don't those add a lot of bulk though? One of the advantages of the rear focal-reducer-adapters is they're actually thinner than a normal glassless adapter...

[buerokratiehasser]

Oh these, speed booster style? Never had them.

Yes the screw-on wideners sport pretty large front lenses, 95 diameter in one case iirc. Try getting filters for these..

Most screw-on wideners DIGITAL bla bla are junk, Holga effect toys, unfortunately teles as well. I suppose with a 320x200 monochrome camcorder the pain is easened a bit.

[glaebhoerl]

I found this article (google translated) comparing them with an 18/4 Distagon. I'm not completely sure what the words are saying, but from the samples, it appears the Speed Booster does much better than the Baveyes and RJ.

[padam]

I don't think it is a good idea for a wide angle.
You probably want good sharpness around the frame and these won't provide it. Also they do increase the distortion which might be hard to correct in post. Possibly more vignetting as well. And the field of view is still a bit tighter than original.

So in short: better saving up for something that is really wide, or just simply go for one that was designed with sensors APS-C in mind.

[glaebhoerl]

Thanks. Are you speaking from personal experience? Or if not, what are your sources? I've been searching for tests and reviews quite a bit (mostly of the Baveyes recently) and there aren't very many with wideangle lenses. (Strange, considering it's a focal length reducer. I especially don't understand the point of all the tests finding that it works well with telephoto lenses. I would much rather carry a 135/2.8 lens than a 200/4 lens with a speed booster, for example.)

But yes, the fallback option is to save for a native 12/2 Samyang. But that's less fun than being able to experiment with different legacy wideangle lenses. (A full-frame Sony camera would be even more expensive and I don't think I'd like it.)

[DigiChromeEd]

Just arrived through my door today is a Zhongyi Lens Turbo II. I've bought it to use my Minolta and M42 wide angle lenses on a Sony Alpha A6000 and Sony NEX5T but haven't had a chance to use it yet.

[Basilisk]

It is always possible that the focal reducer is revealing poor quality edges in the legacy wide angle lenses that were not designed for use on high res digital sensors. Ultrawides have always been challenging lens to design, and it is an area in which there has probably been more progress since computer aided lens design came along.

You really need someone who tests focal reducers on a crop sensor against the original lens on a full frame sensor to compare results.

[iangreenhalgh1]

The focal reducers introduce field curvature and spherical aberration.

Better to use a high quality wide angle adapter on the front of the lens.

[ManualFocus-G]

I have a Lens Turbo II for Fuji X. Decent wide lenses, like the Zeiss Distagon 28/2.8 actually work very well on it. The difference from a full frame shot with my 6D is not that great, although the Lens Turbo shot is cropped slightly.

IQ in the borders is way better than with the original Lens Turbo, which was pants in my opinion!

[enzodm]

This is a Mir 20/3.5 on a chinese focal reducer. Quality decreases on borders, however I would like to see a comparison on full frame, to distinguish between focal reducer and lens contribution.

[ManualFocus-G]

Never mind the focal length reducer, I need a book case that size for all my son's books and toys

[iangreenhalgh1]

Good to know the LT II is better than the original. The original had weak edges due to field curvature.

[IAZA]

Lensturbo v1 & Distagon 25/2,8, nex5




Lensturbo v1 & Rokkor 28/2 MC, nex5

[enzodm]

[meanwhile]

The Lens Turbo II does do pretty well. It seems to be the best bang-for-the-buck.

[IAZA]

[hemeterfilms]

I used a Lens TurboII for Minolta on my NEX 5N which I thought did rather well with the 70-210 f4, the 35-70mm f3.5 and also the 24-35mm f3.5. The two zooms are shown in the pictures of the basilica in my gallery here, the suicidal guy playing with a pole transformer is the 70-210 f4 at 200m. All handheld and probably at about f5.6

http://www.dpreview.com/galleries/1899864608/albums/lens-turbo-ii