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John Mitchell

Why did this fail QC?

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I appreciate that Alamy is always right, but I am honestly confused about why this image failed QC. It was tagged as "soft and lacking definition" and as having noise. However, to me it looks as sharp across the frame as many other images that I've successfully submitted, and I can't find the offending noise. What did I do wrong? All suggestions welcome.

 

http://www.photoshelter.com/mem/img-get/I0000YbnfbES8wgo/s/1000?1362803054

 

Thanks.

 

-John M

Edited by John Mitchell

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Getting "Image Temporarily Unavailable " John.

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Getting "Image Temporarily Unavailable " John.

 

Hmmm... That's odd. The link is working fine for me. Here's another option. However, the image isn't as large as the one linked to above.

 

pd3526277.jpg

Edited by John Mitchell

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John, I think your link hasn't worked because you've copied a link to your personal photoshelter collection while you were logged in rather than take a link to your external website. A slight modification seems to do the trick though:

 

http://www.photoshelter.com/img-get/I0000YbnfbES8wgo/s/1000?1362803054

 

To answer your question people will probably need to see a 100% crop of a couple of areas of the image though. I would personally look at area of foliage in the foreground and maybe a section of the building with some sky.

 

Edit: for some reason I'm not alowed to post an image, only the link. Anyone else getting that problem?

Edited by Craig Joiner
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John, the exif says you use ISO 800. I cant see your image on 100%, but on my camera ISO 800 will show noise.

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Thanks very much for the suggestions. Yes, the photo was taken at twilight at ISO 800 (f/7.1). The camera I used was the Sony NEX-3, which has very good noise control at ISO 800. At 100% the whole image looks virtually noise-free to me. I didn't apply any noise reduction because it didn't seem necessary. Perhaps I need to sell the farm and buy a high-end monitor.

 

Also, nothing in this image comes anywhere close to the samples of "soft and lacking definition" and "noise" that Alamy provides in its submission guidelines, which leaves me totally confused. I guess what really bugs me is that I know that from a buyer's POV, there is absolutely nothing wrong with this shot. If Alamy QC is going to start being this picky, I think that they need to supply updated examples of what they do and don't want.

 

And thanks, Craig, for fixing the link.

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ISO 800 for a static image: why?

 

Low light and no tripod handy. So I had no choice because I wanted to ensure as much DOF as possible.

Edited by John Mitchell

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ISO 800 for a static image: why?

 

Low light and no tripod handy. So I had no choice because I wanted to ensure as much DOF as possible.

Well, I'd suggest that's the source of the problem...

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ISO 800 for a static image: why?

 

Low light and no tripod handy. So I had no choice because I wanted to ensure as much DOF as possible.

Well, I'd suggest that's the source of the problem...

I don't think the 1/40 sec helped!

Can you get back there with a tripod?

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ISO 800 for a static image: why?

 

Low light and no tripod handy. So I had no choice because I wanted to ensure as much DOF as possible.

Well, I'd suggest that's the source of the problem...

I don't think the 1/40 sec helped!

Can you get back there with a tripod?

 

1/40th sec should have been fine with a 16mm lens using the old 1/focal length rule. The picture was taken in Cancun, Mexico, which unfortunately is a bit of hike from where I live in Vancouver.

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We haven't yet seen a 100% crop so we can't judge.

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While we're on the subject of noise. Since this image failed QC, I've been looking more closely at other photos that I took on the same recent trip to Mexico. Some of them do appear to have more noise in the skies -- especially deep blue ones --  than I'm used to seeing. It was very hot where I was -- over 30C most days -- and I'm wondering to what extent high air temperatures can affect camera sensors and cause them to produce noisy results. Has anyone encountered this? I've done a lot of shooting in hot places, and this is the first time I've noticed this type of thing. However, this trip was the first time that I used my Sony NEX-3 instead of a regular DSLR in a tropical climate. Perhaps this particular camera's sensor is prone to overheating in hot weather (?).

Edited by John Mitchell
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"1/40th sec should have been fine with a 16mm lens using the old 1/focal length rule"

 

John. Interesting point you make. (Quoted above)

 

I wonder if this "rule" really holds water with digital images, especially where they are going to be judged at pixel level.

My thoughts are - if the speed is slow enough to get some camera shake it will show up at pixel level regardless of focal length. (??)

 

It would be interesting to hear the thoughts of someone more technically minded than me - that's probably most of you :)

 

Christine

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Still interested in seeing a couple of 100% crops. As Craig said, the shadow area around the plants and a bit of sky/building would be the likely culprits.

 

Perhaps the assessors take into account the circumstances of the shot, e.g. dim market interior where tripod impossible would be viewed more leniently?

 

Re the lens, presumably you need to multiply the focal length by the crop factor - but that's still only 24mm. Is it image stabilised?

Edited by Bryan

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1/40th sec should have been fine with a 16mm lens using the old 1/focal length rule.

 

"Should have"... I don't quite understand your reasoning. Alamy aren't critiquing your general approach to photography, but only the perceived sharpness of an image you submit. 

 

At 100% the image either 'snaps' into focus... or it doesn't...

Edited by John Morrison
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Even at full size it does not look sharp to me and generally fuzzy especially around the foilage and it is difficult to find anywhere sharp, even the top of the building has evidence of camera shake. Not sure about the noise level as that looks ok but QC are going to mention everything bordering wrong once they start to fail an image. I have many images with more noise that have been taken in low light and at night but sharpness is never an issue with a vast amount of shots taken at 3200.

Strongly suggest looking at your hand holding technique and/or various other steadying methods such as walls/beanbags/mini tripods etc.

Andy

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If Alamy QC is going to start being this picky . . .

 

In the absence of requested 100% crop, how picky is "this picky"?

 

dd

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it kind of look a little soft to me. Probably some noise adds to softness... but without the crop it's impossible to really see it.

when I take pictures at 800 iso I make sure I don't correct them at all: that way you don't get noise on your pictures.

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Chistina, are you the dottoressa who I suggested the UpStrap for? I notice there's another female Chris on the forum who seems to live in Bella Italia.

 

John, without 100% view we are all guessing as to what the problem is. I did notice you are using a sRGB color space instead of the preferred, larger aRGB color space. This should not be a reason for failing QC however. 

Edited by Ed Rooney
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Chistina, are you the dottoressa who I suggested the UpStrap for? I notice there's another female Chris on the forum who seems to live in Bella Italia.

 

John, without 100% view we are all guessing as to what the problem is. I did notice you are using a sRGB color space instead of the preferred, larger aRGB color space. This should not be a reason for failing QC however. 

 

That's odd, I always have my cameras set up for the aRGB colour space. I must have converted this shot to sRGB by mistake. Thanks for pointing this out. I'll check into it.

 

Regarding your question about whether or not the old 1/focal length guideline still holds, I imagine that it doesn't for the NEX cameras because they don't have a flapping mirrror (hadn't thought of that). So I guess that theoretically we shoulld be able to handhold mirrorless cameras at even slower shutter speeds.

 

Bryan, this shot was taken with the Sony e-mount 16mm lens, which isn't stabilized.

 

I might get around to making 100% crops.  However, at this point I'm ready to concede that Alamy is always right. Personally, I quite like the slight softness. It goes well with the mellow lighting and subject matter IMO. Chacun a son gout, as the French say. I certainly will have no qualms about selling this image on my own and submittting it elsewhere.

 

Thanks for all the varied feedback. Much appreciated. From now on I promise to keep a bean bag in my cap for stabilzation purposes.

Edited by John Mitchell

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double post -- sorry

Edited by John Mitchell

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ISO 800 for a static image: why?

 

Low light and no tripod handy. So I had no choice because I wanted to ensure as much DOF as possible.

Well, I'd suggest that's the source of the problem...

I don't think the 1/40 sec helped!

Can you get back there with a tripod?

 

1/40th sec should have been fine with a 16mm lens using the old 1/focal length rule. The picture was taken in Cancun, Mexico, which unfortunately is a bit of hike from where I live in Vancouver.

 

The old rule of 1/focal-length doesn't apply any more to digital high resolution cameras. Due to the increase in resolution the camera is more "sensitive" to shake, therefore a the rule has to be changed to something like 1 / (2 x focal-length).

 

And even the old rule had a lower limit like 1/60 or so (depending on the photographer).

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ISO 800 for a static image: why?

 

Low light and no tripod handy. So I had no choice because I wanted to ensure as much DOF as possible.

Well, I'd suggest that's the source of the problem...

I don't think the 1/40 sec helped!

Can you get back there with a tripod?

 

1/40th sec should have been fine with a 16mm lens using the old 1/focal length rule. The picture was taken in Cancun, Mexico, which unfortunately is a bit of hike from where I live in Vancouver.

 

The old rule of 1/focal-length doesn't apply any more to digital high resolution cameras. Due to the increase in resolution the camera is more "sensitive" to shake, therefore a the rule has to be changed to something like 1 / (2 x focal-length).

 

And even the old rule had a lower limit like 1/60 or so (depending on the photographer).

 

Interesting. Thank goodness for image stabilization technology. Way back when, with my old manual focus cameras, I found that, if I was careful, I could shoot at shutter speeds slower than 1/focal length without external support and often get accceptable results. However, we didn't eyeball everything at 100%. Extreme pixel-peeping has become something of an obsession now, at the expense of content and a lot of other things IMO. But that's another story...

Edited by John Mitchell
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Oh, Alamy? It seems that Signorina Christina di Milano's image connection is showing my images. I'm sure the young lady would prefer to show her own images. 

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