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CA QC fail-really?


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Hmm. The one before is worse.

It does all rather confirm that after the first (and second) offences one is more carefully watched.

Odd that the first post-fail batch was failed in an hour. Perhaps they took pity on me.

No sign yet. of the subsequent batches though. Fingers crossed overnight.

Thanks Martin and all.

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Sony 18-55 kit. It's never been an issue before.

 

I have hundreds of images on Alamy that were taken with a Sony 18-70 kit lens. Can't remember having a single CA failure with it, but QC is much stricter now. Many of those images wouldn't pass today. I used a program called PTLens to clean up CA at the time. Have subsequently sold that particular kit. As mentioned, current Sony cameras have built-in CA correction. Works like a charm, even with iffy wide angles. Don't believe the a55 has that feature, though.

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To my eyes, the biggest problem in both corrected and uncorrected versions is the purple fringing around the face, and the hair in front of face, of the girl on the right.

 

Definitely a fail in my books.

 

Good to see a 100% example of a QC fail. Thanks. It's very helpful. 

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A way to help if CA tool isn't enough…..

 

In PS duplicate layer.

Change blend mode to colour.

Go to Filter-Blur-Gaussian blur.

Adjust to about 3 - 5, checking image to see CA disappear.

Add layer mask. Fill with black. Paint back in white on areas you want.

 

I sometimes use this if I think the image is worth the work.

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As Keith mentioned above your corrected version still shows some CA.

 

I checked in Photoshop and simply ticking the CA removal box in Camera RAW does 90% of the job. There's still a tiny bit of fringing in the corners of the image and along the girl's face as others have mentioned which can be cleaned using the fringe sliders.

 

I  think even 'borderline' CA should probably constitute a fail as it's just such an easy thing to fix in 99% of cases. Offtopic: I also notice some JPG artifacts in the sky, and along the rope in top of frame which you may want to clean up before resubmitting. 

 

Interesting to see a full-size CA failure, thanks for posting.

 

-Jason

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OK, now I see the CA. I had clicked on the magnifying glass only once. Too messy for sure. QC now expects no CA at all, it seems. 

 

Tough lighting situation as well with all the white paint, high contrast areas, and harsh sunlight. I recently took a bunch like these on a ferry in the middle of the day and canned the lot for various reasons.

 

P.S. It might be worth downloading a trial version of PTLens (see my post above). I think it might be able to clean these image up. Worth a try, anyway.

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1+ for PT Lens, which I've had to use in the past for a really bad lens (Sigma 12-24). Now ACR takes care of most of CA. However with the Sony RX100 I see similar problems as with this Sony. The RX100 is a lot less easy to correct though.

Here's a sample of the Sony 18-55 at 18mm and F8. When I see this I would never think of trying to use a straight JPG from this lens. Only RAW.

 

wim

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The simple thing to do would have been to remove my customary +20 saturation preset.

With a defringe it's now much better. Not vanished though and I will try the various PS tips if I can work out how!

Thanks all.

I really have spent far too much time on this image- hope none of you feel the same way!

http://i5.photobucket.com/albums/y180/markrhdunn/DSC01817-3.jpg~original

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1+ for PT Lens, which I've had to use in the past for a really bad lens (Sigma 12-24). Now ACR takes care of most of CA. However with the Sony RX100 I see similar problems as with this Sony. The RX100 is a lot less easy to correct though.

Here's a sample of the Sony 18-55 at 18mm and F8. When I see this I would never think of trying to use a straight JPG from this lens. Only RAW.

 

wim

 

I'm using the Sony e-mount 18-55, and JPEGS with in-camera (NEX-6) CA correction turned on are as clean as a whistle. I also use this lens with my "old" NEX-3, which doesn't have in-camera CA correction, and I can usually easily clean up any CA with PTLens. I've never had a CA failure. Haven't used the Sony A-mount 18-55, though.

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This is where good glass really earns its money. I recently bought the Canon 100mm 2.8L IS Macro lens, having used mostly kit lenses before or 18-200mm zoom. This prime lens has made all the difference. I used to spend HOURS getting rid of CA, now it is no longer a problem for me. I will using primes only from now on.

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The simple thing to do would have been to remove my customary +20 saturation preset.

With a defringe it's now much better. Not vanished though and I will try the various PS tips if I can work out how!

Thanks all.

I really have spent far too much time on this image- hope none of you feel the same way!

http://i5.photobucket.com/albums/y180/markrhdunn/DSC01817-3.jpg~original

 

Yes, good thing we're getting paid by the hour. B)

 

I still see CA -- e.g. around the girl's (one snapping the picture) shoulder, under her hair, and along the diagonal supports or whatever they are. No problem submitting this a couple of years ago. But not now IMO.

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The simple thing to do would have been to remove my customary +20 saturation preset.

With a defringe it's now much better. Not vanished though and I will try the various PS tips if I can work out how!

Thanks all.

I really have spent far too much time on this image- hope none of you feel the same way!

http://i5.photobucket.com/albums/y180/markrhdunn/DSC01817-3.jpg~original

 

Mark-

 

The CA is still very apparent unfortunately. No photoshop trickery needed, just tick that little box!!

http://www.reciprocityimages.com/images/temp/spacecadet_CA.jpg

 

That is the JPG simply opened in Camera RAW and the Remove CA check bock ticked... Cleans up easily after that with remove fringe sliders. Not magic. Takes two seconds! Shooting RAW would of course give higher quality correction!

 

It's not about this particular image- You've only spent too long on it if you haven't learned something for the next batch.  :)

 

-Jason

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My ACR only has the sliders. There's no 'remove ca' box.

Strange? It doesn't look like this:

http://www.vineet-suthan.com/photoblog/wp-content/uploads/2013/02/PhotoshopScreenSnapz002.jpg

Which version? This has been an option as far a I can remember, but perhaps not.

 

Do you have LR? The controls are identical.

 

-Jason

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My ACR only has the sliders. There's no 'remove ca' box.

Strange? It doesn't look like this:

http://www.vineet-suthan.com/photoblog/wp-content/uploads/2013/02/PhotoshopScreenSnapz002.jpg

Which version? This has been an option as far a I can remember, but perhaps not.

 

Do you have LR? The controls are identical.

 

-Jason

 

 

Automatic CA tick box came with IIRC LR4.

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I only have CS4 and LR2.

My mistake- You camera RAW version would be probably 5.7 which does not have the tick box!!

 

Maaaybe worth a LR upgrade, as perhaps you are spending more time with correcting and QC failures than you are saving money?

 

Otherwise, when you do your CA correction, try at 200-400%. If you are having trouble seeing the CA that is there this may help adjust the sliders properly.

 

-Jason

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Alamy income doesn't justify upgrades, sorry.

As to 400%, whatever happened to images only having to pass at 100%? Have the goalposts not only moved, but been magnified?

No reason to be sorry, was just a suggestion- it's your decision and does not affect me!

 

The CA is clearly there at 100%. I only suggested looking at higher magnification for correction as you said you could not see it. It just might be easier to dial in the correction with a bit more precision.

 

-Jason

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As to 400%, whatever happened to images only having to pass at 100%? Have the goalposts not only moved, but been magnified?

 

I can't see anyone other than you suggesting images have to be approved at higher than 100%, which is plain silly.

 

Jason's suggestion, for someone who can't see the CA at 100%, was an excellent one that I think deserves thanks, not distortion. But of course, that's just how I see it . . .

 

dd

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