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Understanding QC for New Contributor


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Hey everyone! CJ here, new contributor and failing QC candidate! :-)

 

Kidding of course but I'd like to truly understand the QC process for the following image.

 

It failed for: Chromatic Aberration - Soft or lacking definition.

 

Details:

ISO: 125
Focal: 90mm
F-Stop: 5.0
Speed: 1/500 sec
Camera: Canon 7D
Lens: 28-300mm IS Handheld

 

Thanks for any insight as I do want to get to a level of acceptance. Cheers!

CJ

 

10658586_292828734259215_813176912950406

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The white scaffolding (fire escape) to the right shows purple along its bottom edge. It does also look a bit soft  but need a bigger picture.

 

You should be able to remove the CA with Lightroom or similar.

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Hi,

I looks to me that someone at QC has got out of the wrong side of the bed. QC is, in the main, correct and when contributors ask the forum they get a wealth of opinions that point in the direction of QC being correct.

In this instance I believe the highlights have been mistaken for CA. I suggest asking Alamy for clarification, mistakes are very rare but they have been known.

 

Andy

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The right had side of the fire escape looks a bit borderline but easily adjustable in LR or PS. It may be useful to blow up your images to 100%, before submission, to check that the image can't be improved on. Maybe caught QC on a bad day!

 

Nice pic - good luck next time round.

 

dov 

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Is the image part of the first submission of four images (I think) to gain upload rights to Alamy?

 

If so, the images will be scrutinized more than usual.

 

Do you shoot in RAW?

 

There is a little bit of CA along the outermost steel structures to the right. I would have removed it before submission. I usually do this easily in Canon's Digital Photo Professional (DPP) - many use Adobe Camera Raw.

 

The image show signs of SOLD - but cannot say for sure if not viewing at full size.

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After another look the centre lower area of the brickwork does look a little soft and combined with the intense visual character of the image could be a reason for fail. As for the CA, I think you have been very unlucky and stand by my opinion of it being more of a problem of blown out highlights on the poles rather than CA.

As Spacecadet has said pick something else and move on. If you can, use a prime lens and of an uncomplicated, well lit image.

Andy

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It failed for: Chromatic Aberration - Soft or lacking definition.

 

Thanks for any insight as I do want to get to a level of acceptance. Cheers!

CJ

 

 

 

To be honest, I wouldn't have worried about any CA here- there's a tiny bit of purple fringing, but I wouldn't have thought it would have failed for that. It's nothing like the example spacecadet showed us (http://discussion.alamy.com/index.php?/topic/2959-ca-qc-fail-really/?hl=fail) a few weeks ago which was more obvious.

 

I do however agree that it's soft, and shows a decent amount of JPEG or compression artifacts.

 

-Jason

 

edit: I had assumed this was a full-size crop, but perhaps not? In that case, at full size it's quite likely that the CA is much more pronounced and would constitute a failure. 

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Mark (and to benefit the OP),

I appreciate that it is not always easy to justify Alamy income with buying new kit but I firmly believe that your problem lies with your 18-55 lens. Now obviously I am not sure that you have used it in this instance but probably so. I am not familiar with the Sony systems but surely you could source (or borrow or try in a shop) a prime lens. The difference is absolutely phenomenal.

I know the Sony diehards are going to say what a wonderful lens it is etc but it is the only thing in the way of your subject and sensor.

It may be that you have a duff lens. I purchased a MK1 RX100 and was gutted by the crap pics produced, masses of CA, soft area etc but was mystified by most of the praise heaped upon it on the forum.

I eventually took it back to the shop and had to convince them with samples how rubbish it was and they eventually sent it to Sony. It came back fitted with a new lens barrell and focus tested etc, it is now a different beast. I now use it for walkabout town stuff in good light and I have had loads accepted with no fails. However that is all I use if for as it comes nowhere proper kit.

I am trying to help here so please read it that way.

There is no substitute for good glass.

 

Andy

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Chromatic Aberration

 

jhfo6h.jpg

 

Soft and lacking definition (to the left and up a little bit from the area with chromatic aberration)

 

23vlq92.jpg

 

Aside from the comments on the lens,  I would also check to make sure the firmware is up to date on your 7D.  I bought one when they first came out and sold it 3 weeks later because I was frustrated with relation to the images I was getting out of the sensor.  I know a few folks that use them today and don't have the same issues that I had - I think it relates to firmware updates that have been applied over the years.  For what it's worth, I've heard the 18-55 lens with that camera is a great combination - I know of three photographers that have told me that.

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