Artefacts problem

[powsnapper]

Both these images were rejected for 'artefacts problem' but I don't quite understand what's wrong. Has anyone else had the same problem - can anyone advise what the problem is with the above photos? Thanks.

[RBChauDavis]

Hi Snapper,

Yes, I have had the same problem.  I have found it effective to look at my images under an 8 to 1 magnification to check for artifacts like color, pixelation, and over sharpening.  Your two images at 8 to 1 are very pixelated,  If I were to guess, I think they have been over sharpened.  I was unable to completely fix the problem with the luminance slider or the clarity slider in LightroomCC 2015.  You might be able to fix the originals.  Some programs automatically sharpen when exporting an image which can cause problems.

Richard

[powsnapper]

Hi Richard

Thanks for your reply.

Due to forum constraints the image sizes were much reduced to enable upload to the forum (max 900 on the longest side) The actual file sizes are trees: 2592 x 3772  6.2MB); rocks:   2872 x 3772 – 10.3MB . When enlarging the forum images they do become pixillated but not so with the originals.  I can send the originals if you would like to look at those.

Regards

Peter (aka Snapper)

[RBChauDavis]

Hi Peter,

I would be glad to look at the originals.  I thought they had a way to link the image in question without uploading again... still, glad to check them and see if I can figure it out.  Did anything I wrote sound new?  There is a real range of expertise here and I fall somewhere in the middle.  You may be way ahead of me.

all the best,

Richard

[RBChauDavis]

Maybe give me a link to a storage site on the web or you can email me at richard@chaudavis.com

[powsnapper]

Hi Richard. Try this....

All the images in this album have been rejected for 'artefact problems': DSC_5087_1409 rough stonework | peter@powfoto.com | Flickr

[RBChauDavis]

Those were still too small or I am doing it wrong.  The largest image I could pull down was 1407x2408 and had the artifact problems.

[powsnapper]

Don't know what's happened there the link should take you to a flickr album where you can view the full size images. No need to downliad...

Peter

[RBChauDavis]

Hi, tried it again not downloading and did a 500% zoom in my google browser.  There was a (new) red fringe on some of the rocks, the other artifacts were reduced similar to using the luminance slider in LightroomCC, the red fringe was a big problem .  The downloads were cleaner but still had artifacts when I looked at them in LightroomCC 2015 at 8 to 1.  I think the programs your using to export and display maybe hurting your images at the end of your process.

Richard

[powsnapper]

Hi Richard

I use Photoshop for post production processing and always check each image at a minimum of 100% before submitting. There might have been a minor adjustment to the lighting / contrast with the wall image because it was taken late afternoon when the sun was going down but other than that and perhaps cropping, they were straight off the camera. 

That said, both were included in a submission comprising two batches of around 25-30 images in each, an unusually high number of submitted images for me. Almost all the images in both batches were rejected for noise/grain problem. Most odd because usually my images are accepted and most of them had previously been accepted without a problem elsewhere, e.g. Alamy (whose QC is very strict). Maybe submitting so many images in one go broke the rules so the whole batch was rejected out of hand. I've submitted several images since but have restricted the submissions to no more than ten images per batch and no more than two batches per week. So far there hasn't been a problem - save one image that needs a property release which I'm dealing with.

Anyway, many thanks for your time and comments. Much appreciated.

Peter