Sony SELP18-105G dissapointing!

[Christopher Young]

Just tried out the new Sony SELP 18-105 G F4.0:1 lens on the FS700...

The lens works well in as much as it doesn't lose focus and 'jink' on the long end when you zoom back like the earlier 18-200. Auto focus, auto iris, stabilisation etc, etc all works well, quite well in fact (note: it doesn't have the video mode 'active' stabilisation of the 18-200. Only 'off' and 'standard'.) The power zoom is much quicker than the SELP 18-200. About three seconds end to end when camera menu set to variable. Strange thing is if you use a Varizoom zoom demand it's about 30% quicker again. About two seconds end to end

The BIG downer is the pronounced pincushion effect on full zoom. In fact it looks like it may have slight barrel distortion at the wide end. This you might just get away with but the pincushion on the long end means I won't be buying it. I believe, though haven't tried yet, is that on an NEX still camera with latest firmware it's not an issue as the still cameras have inbuilt software correction for these anomalies. Sadly no correction for the video camera end of the family.

Have attached a still of the long end pincusion. Didn't worry about the wide end as I felt that was pretty minimal barrel distortion but the long end, phew!

Chris Young
CYV Productions
Sydney.

[Darren Levine]

shame, as it's an interesting lens.

have you tried any post correction? in premiere using the lens distortion effect with some negative numbers can do some nice correction, and it's keyframable, so you could have it actively correct a zoom.

post a sample clip if you like and i'll correct it

[Christopher Young]

Yes its correctable but would you want to correct every shot on a multicam two hour show? The time required alone to correct a single zoom shot let alone dozens and dozens of them that go from mild barrel distortion to pincushion would be totally unrealistic IMHO.

Will be interesting to see if Sony can come up with a firmware solution.

Chris Young
Sydney

[Steven Reid]

I won't post a link, but a very spirited and informative thread on another site absolutely lambastes this lens. It was never meant for the FS series of video cameras, though Sony evidently has not made that tidbit apparent. Thank goodness I read the scathing reviews of early buyers: I was just about to pull the trigger.

[Erik Wittbusch]

There will hardly be any firmware to integrate in camera correction of lenses.

All the other NEX cameras but the FS100/700 use photo sensors and "squeeze" the video signal out of the megapixels. This alone is enough room for the correction.

The FS100/700 use dedicated video sensors and don't hve that extra megapixels and processor, that can handle this kind of operation.

[Gabe Strong]

The FS100 and 700 do not have the same sensor. The FS100 has 2.2 MP and the FS700 has a lot
more. I know the FS700 shoots 8 MP stills so at least that or more on its sensor. Might that be
enough for firmware correction? I dunno but the two cameras have very different sensors.....

[Erik Wittbusch]

The sensors are different, but not that much.
Both are dedicated video sensors which have a full pixel readout
at 1080 (FS100) or 4k (FS700). One can say, that they use a
similar way of processing the resolution in contrary to the
VG and EA50 cameras, which use line skipping/pixel binning.

[Alister Chapman]

The FS700 is a 4K sensor with a primary active area that is 17:9. The FS100 has approx 2.3K pixels in a 16:9 active area.

Both sensors, but particularly the FS700 sensors have a lot of unused or at least "non active" pixels. The FS700 sensor is 11MP with only about 8.8MP "active". So there are a lot of spare pixels. Some of these are used for black balance and noise compensation but when you use the cameras active stabilisation there is no change to the image size or resolution, so there must be extra pixels around the main active area that are used as part of the stabilisation process. These could be used for image correction, but the bigger issue is that this would have to be done in real time and at up to 60fps, so some serious number crunching and power requirements.

[David Elkins]

I had this lens for a couple of days before sending it back due to the terrible distortion. Spoke to Sony and they said that a fix may happen, but it would not come before spring. Bummer.

[Dave Allen]

Wow, how does a company with a name and rep like Sony send out such garbage.

[Christopher Young]

there must be extra pixels around the main active area that are used as part of the stabilisation process. These could be used for image correction, but the bigger issue is that this would have to be done in real time and at up to 60fps, so some serious number crunching and power requirements.

I have seen 50p AVC HD footage shot on the Sony NEX 6 with this 18-105 lens and it manages the correction in real time so Sony can do it. No issues on the NEX 6, the verticals at full zoom are straight. I guess it's whether Sony feel they will sell enough lenses to the FS100/700 brigade to justify a firmware fix.

Chris Young
Sydney

[Phil Goetz]

Hmmm. G lens...

[Steven Digges]

Phil, your point?

According to Sony "In the α lens lineup at Sony, G Lenses stand shoulder to shoulder with the outstanding Carl Zeiss optics."

Link here: G Lenses – Concepts behind the "G"

If you are saying what I think your are I agree. This is not a Zeiss class lens, but Sony claims it is. Look how Sony defines them. If one was to see this Sony page first why would he ever think for one Second that ANY G series lens would not work well on his FS700. Especially when you are going Sony to Sony in the native mount. Is that what it has come to now? Native compatibly can no longer be assumed. When doing our purchase research we must also check "known product compatibility lists" for everything? If Sony is going to market it as a high end lens but knows it will not work with a high end camera with that mount it should be made more clear than it is.

Steve

[Gabe Strong]

Yup, that's why I bought it. G branded lens? Perfect for the FS700!
Yeah I didn't check the compatibility, just assuming it would be a high
quality lens.