Shocking CA on Nikon 85mm f/1.8G, normal?

Eyon

Eyon

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Ian
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Wide open my Nikon 85mm f/1.8G has horrific CA. Is this a normal standard on this lens or have I got a problem with mine?

Stopped down to 2.8 or beyond it improves, but half the fun of a 1.8 or lower lens is that shallow DoF, which in my case can sometimes be unusable.

Duff lens or to be expected?

Lightroom CA removal doesn't touch it. This is a 100% crop of the worst area on a subject I randomly snapped to test it. It also happens around hair in high contrast areas.

Nikon D800, ISO 100, f/1.8 1/320

 
I don't have this lens so can't compare, but the edges you're looking are at are extremely contrasty with the bright sunlight causing harsh shadows and blown highlights on the edge of the buttons.
Look at the buttons in the shade and there is no CA whatsoever.

I did have a go in LR and managed to get rid of the majority of it, although you need to choose the eye dropper and pick the colours and then tweek the strength.

19971-1527080133-fdc7751d74281fdfb7645248cdce3727.jpg
 
Thanks @ecoleman, I appreciate the photo itself is very poor, but it was the most dramatic example of the CA I have seen whilst finding things to photograph to show the problems. A similar picture on my 50mm f/1.8 produces far less, almost negligible, CA.

Nice to know it can be edited with a fair effort, but I'd be interested to hear from owners of this lens if this is an issue.
 
C.A performance on all of the Nikon f/1.8G lenses isn't great, it can be solved by stepping down a bit.

The f/1.4G lenses are a little better but in horrible light like shown in the example above they would struggle too.
 
gremlin16 said:
Isn’t the CDU backlit with green? I can’t explain the purple though? Where were you going? Anywhere nice?
Click to expand...

Nope, the FMC on the Embraer is backlit with white. As you can tell from this photo it's getting bright sunlight so all flight deck lights off. I've seen it when taking photos of my other half, who has very dark brown hair, against a white backdrop, though less extreme than this poorly lit example.

Perhaps a quirk of the lens, but one that may cause me to sell it, can't live with this sort of CA.
 
Can't say I've noticed it. One of my favourite lenses.
 
It is prone to CA but that’s pretty severe, I never saw anything as bad as that.
 
Just about all fast lenses will exhibit some form of CA (true apochromatic lenses are rare). If you photograph a subject with high contrast/backlight and at or near MFD then it will usually show the worst of it, especially towards the edge of the frame (no idea if this is near the edge). Hardly shocking.

Basically, if you look fro problems you'll find them.
 
FWIW, canon 85mm's all do the same to varying degrees. It always looks worse at 100%.
I use the manufacturers lens correction profiles if it become bothersome.
 
kingo15 said:
Never seen anything like that on mine
Click to expand...

It needs bright highlights and very contrasty areas with a little bit of defocus to manifest so badly. If you take away one component it will be hardly there. But if you like contrasty light, lots of backlight shining through and very contrasty subject then you should look elsewhere.
 
LongLensPhotography said:
It needs bright highlights and very contrasty areas with a little bit of defocus to manifest so badly. If you take away one component it will be hardly there. But if you like contrasty light, lots of backlight shining through and very contrasty subject then you should look elsewhere.
Click to expand...

Good description. It's spherochromatism which is a bit of a made-up term that combines several aberrations including spherical aberration and both flavours of CA (chromatic aberration, lateral and axial). Sometimes also referred to as colour-bokeh.

It's common to many fast primes, but usually only visible when there are a lot of bright, out of focus highlights. Sometimes the CA removal tool in software gets rid of it nicely, other times the colour fringing dropper is called for. Occasionally it's very hard to get rid of completely.
 
Is it worth remembering that this is a 100% crop of something of a worst case scenario?
 
Thanks all for the replies. I kept going around taking photos of things in vaguely contrasty situations and I could replicate it every time, even in less extreme circumstances as above. For those interested, see this is the 100% photo, SOC. Again I'll repeat, it's a terrible photo, certainly not something I'd normally share to the public, but it was more a test case.



I ended up returning it (guys in the store agreed it was a duff lens) today and purchased the Sigma 85 f/1.4 Art and I'm over the moon how different it performs. Can't wait to get photographing with it.
 
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The Sigma 85 art is probably top of the 85 tree even Otus considered.
 
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