Whatever you might think about Alamy QC failing images for "soft or lacking definition", as explained here, so far those of us who frequent the forum have yet to see a picture that the photographer can show at 100% to be free of some kind of flaw. Since I seem to be capable of creating pictures that are soft and lacking definition on demand I thought I would put up some more examples for those who are still in denial about it.
Last week I had just such a moment. I'd had no failures for a week or so and was thinking all was fine and then three times in a row I got a soft and lacking definition failure. It turns out that the two photos responsible for the failure are soft, as follows (shown as 100% crops of the original 48+Mb files):
This one is most likely mis-focussed @ 1/350s f10 31mm handheld
This one is most likely the subject moving and/or mis-focussed and to cap it all, there is clear CA at the edges of the bird @ 1/800s f8 400mm VR handheld
Don't stare at them too long, they hurt your eyes (that's a clue!).
Alamy QC seem to do a very simple thing, they zoom to 100% in the centre of the image (which is the quickest check they can do). So, apart from scanning across the image for dust and odd birds and things, I would do a final check by zooming to 100%, dead centre and if it ain't right, don't submit it.
Here's other common effects that gets the dreaded soft and lacking definition failure:
This picture was taken at high ISO and then noise reduction was applied heavily leaving a painterly effect @ ISO1600 1/60s f4 18mm handheld
This picture has been interpolated up from 6MP RAW NEF to 71.8Mb 8-bit PSD showing "jaggies" on the edges @ 1/1000s f5.3 300mm VR handheld
The other failure which is poorly understood is demonstrated in the following images, "chroma noise is something you get with older digital cameras, low MP cameras and at higher ISO settings:
The lower half shows chroma noise, the upper half has had the noise removed.
This shot shows the chroma noise exagerated by pushing the saturation to 100%.
Alamy have written a guide to removing chroma noise and some other retouching techniques, here
Hope that helps...
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6 comments:
Stumbled across your excellent blog just by Googling "alamy qc"
Great images illustrating soft and lacking definition. Should be compulsory viewing for all who don't "get it"
Very good illustrations of the dreaded s&ld!
One other I often see in 100% size failed images is Chromatic Abberations (CA). Most often at the edges of frames around contrasty edges on wide angle shots.
CA can be removed in Lightroom, ACR 4 or PS by using the Lens Correction panel. Its pretty unsightly at 100% and I'm sure those who do not bother to remove it may just tip the balance in favour of a QC rejectio0n in borderline cases.
PP
Good point PP. They do have a category for CA but I reckon, like you, that it can be a contributing factor on softer images.
Doesn't correcting CA inherently soften the image though (actually I'm not sure, but by eye I would say yes)? I have occasionally avoiding correcting minor CA if it is not likely to be discernible in the end usage, to avoid another round of processing losses. I've a much better lens now which doesn't show CA as obviously (16-85 DX VRII)
I've never really understood why you hide behind a pseudonym on the Alamy forum, and also here on your blog. You even omitted to give the URL for your blog when you wrote about it in the Alamy forum recently.
Who do you think you are - "The Stig"?? Ok, well maybe you ARE the The Stig!
Have the courage of your convictions and come out from the shadows. You never know, fame and fortune may await you!
Stephen Power (this is my real name)
Well, you found me, and the links to my Alamy pages are in my name...I'm not sure I'm ready to get to know you all just yet though!
CA can be removed with the LAB mode too, for those guys who haven't got the latest Photoshop:)
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