Looking for high-quality normal zoom

[TomH]

Probably going to buy a nex-6 in the near future and am looking for a good zoom to go with it. The 16-50 and 18-55 kit zooms are not what I'm looking for, so I'd appreciate any recommendations on higher-quality alternatives.

What I'm specifically looking for:
Roughly 18-50mm range.
Very low chromatic aberrations (axial, transverse, spherochromatism).
Good corner sharpness, even to extreme edges.
At least f/4.0 throughout range.
Auto-focus on nex.
No power zoom.
No focus-by-wire if possible.

Any manufacturer is fine, and adapters are fine as long as auto-focus is retained. If there are no auto-focus options, I'd be interested in suggestions for a lens fitting the other criteria.

Thanks!

 

[serhan]

Welcome to talknex. If you don't mind the dslr lens size, you can try the Sony A mount lenses with the Sony lea-2 adapter. The af speed is same as using Sony crop dslrs. Here is 16-50 f/2.8 lens:

Sony 16-50mm f/2.8 DT Standard Zoom Lens SAL1650 B&H Photo Video

 

[Bimjo]

Taking serhan's info a step farther- a dslr lens and the LA-EA2 are the only options that meet your criteria at this point in time. Perhaps the mythical "G" zoom on the roadmap will fit your needs, but we'll have to wait and see until it actually materializes.

And welcome to TalkNEX.

 

[TomH]

Thanks for the welcome & suggestion serhan, but this lens shows some of what I'm trying to avoid.

You can see this clearly in the crops shown here about halfway down the page. At both 16 & 24mm the edges are not sharp at all, and do not improve on stopping down. Same with the CA.

I don't expect perfection (lens design is basically a massive optimization problem after all), but I'm looking for something that has really good corners even at the expense of some center sharpness.

Size isn't really a problem. If it were available I'd love to get an alpha-sized body with a nex mount for flexibility.

 

[Poki]

If you want good corner performance, there are essentially two options: Going with primes or full frame (35mm) zooms to get the crop sensor sweet spot advantage. So there is no lens meeting your criteria. The only one which come close (only the focal lengths are slightly out of your wishes) are the Sony Zeiss Vario-Sonnar T* 16-35mm f/2.8 and the Sony Zeiss Vario-Sonnar T* 24-70mm f/2.8. Both have "real" manual focus (although I think the difference to focus by wire is not really noticeable if you use high end E-Mount lenses, i.e. the Zeiss ones), fast AF with the LA-EA2 adapter and pretty good corner performance, especially on APS-C sized sensors.

But there's a price to pay in size, weight and, of course, money. If you can't pay this toll, you'll have to make a compromise somewhere else.

 

[TomH]

Thanks for the info Poki. Those lenses are out of my price range. I'm looking to spend maybe $500, stretching to $800 if it really has everything I'm looking for. Any other suggestions if I go full-frame with the lens and use the adapter, especially if I accept focus-by-wire?

I really just wanted a high-quality all-purpose zoom that retained autofocus. Most other lens requirements I can meet with primes.

 

[Bimjo]

I've used the Tamron 17-50/2.8 on my Pentax bodies and was happy with it. I'm not sure it will meet your edge/corner requirements, but you might check it out.

 

[serhan]

You can also check the other zooms for Sony apsc cameras like Sony Zeiss 16-80mm, Tamron 17-50mm, Sigma 17-50mm, and Sigma 17-70mm lenses:

Sony Alpha APS-C Sensors Standard Zooms 35mm & Digital SLR Lenses | Buy, Compare & Review | Adorama

Zeiss review Zeiss Vario-Sonnar T* 16-80mm f/3.5-4.5 ZA DT ( SAL-1680Z ) - Review / Test Report

For other lenses you can check canon/nikon mount tests: Photozone Tests / Reviews

Other option is Fuji EX1 with 18-55 zoom. You can buy the combo as used for a little over $1000 in US and the combo is smaller then adopting dslr lenses. Fuji has one of the best kit lens comes with a camera:
Fujinon XF 18-55mm f/2.8-4 R LM OIS (Fujifilm) - Review / Test Report

 

[davect01]

Taking serhan's info a step farther- a dslr lens and the LA-EA2 are the only options that meet your criteria at this point in time. Perhaps the mythical "G" zoom on the roadmap will fit your needs, but we'll have to wait and see until it actually materializes.

And welcome to TalkNEX.

Ya, with wanting AF, the range you want, and excluding the two you already have, the A mounts via adapter are your only choice.

The biggest downside is the focus slows down via the adapter.

 

[Poki]

Ya, with wanting AF, the range you want, and excluding the two you already have, the A mounts via adapter are your only choice.

The biggest downside is the focus slows down via the adapter.

Focusing A-mount lenses with the LA-EA2 should actually be faster than focussing native E-mount lenses.

 

[davect01]

Not having the adapter myself, I am reporting on what 95% of those who have it say.

THEY say a A mount lens focusing speed with the adapter is slower than a native E mounts.

 

[Poki]

Yep, with the LA-EA1, it definitely is slower. But I can't imagine how the LA-EA2, which technically is the same focusing module as built into the A65, could be slower than native E-lenses. But I don't own one either, so this all is only guessing.

 

[TomH]

Thanks for the suggestions everyone. I've been looking at reviews of those lenses, and the two I like most are the Tamron 17-50 2.8 and the Sony Zeiss 16-80 3.5-4.5. Looks like I'll probably save up a little longer and get the 16-80 with an extended warranty, since it has better corners over the ranges I'd use it.

I don't really mind using the LA-EA2 (other than the extra cost), and even with the 16-80 it should be smaller than what I regularly carry around now.

The Fuji EX1 doesn't seem to have focus peaking, which along with some of my other body requirements eliminates everything but the NEX-6. The kit lens does look like it performs well, so hopefully Sony will follow up with a better compact lens at some point.

In case anyone else is trying to find a zoom lens with good corner performance, I've summarized what I learned along the way:

Overall:
Most of the Sony Alpha & NEX APS-C lenses are not well corrected for chromatic aberrations or blurring in the corners, even when stopped-down.
On average the Alpha mount lenses have less corner issues than the E mount lenses, which is probably something that has been sacrificed for size.

Tamron 17-50 2.8:
There are 2 versions, one with VC stabilization and one without.
The version without stabilization is better optically (see comparison here an a canon mount).
There appears to be some copy-to-copy variation in quality.
Some chromatic aberrations that require correction exist at all focal lengths, but are less than those typical of similar Sony lenses.
I would personally use it stopped-down to at least 4.0 for the gain in quality, which largely negates the usefulness of the 2.8 aperture for me.

Sony Zeiss 16-80 3.5-4.5:
Multiple revisions seem to exist, possibly to correct parts that wore out very quickly in early batches.
Corner performance is not so good from 16-20mm, but becomes very good from about 20-80mm especially when closed 1 stop.
Warranty is only 1 year, as opposed to the Tamron's 6 years.

 

[Amamba]

You may also want to consider Sigma 17-50/2.8 OS. While shooting Canon I used to have Tamron 17-50/2.8 non-VC and switched to Sigma. The optical performance is slightly better and it has stabilization.

 

[TomH]

You may also want to consider Sigma 17-50/2.8 OS.

Thanks for the suggestion Amamba. I did look at that Sigma as well, but was more impressed by the Tamron. Going by the comparisons I've seen (such as here and here) the Sigma appears worse in corner sharpness under almost all circumstances. This is on a Canon mount as well, meaning there will be worse performance on the slightly larger Sony sensor.

I'd actually be fine with the alternative of a slightly longer range of very roughly 28-110, then getting wider prime for when I need it. Anyone have suggestions for APS-C or FF lenses in this range with great corner quality (on APS-C of course)?

 

[Amamba]

I actually had Tamron 17-50/2.8 and replaced it with Sigma. I didn't notice any degradation in corner sharpness, and Sigma has better AF speed and is also stabilized.

However, Zeiss sounds like a winner.