Luminous Landscape Forum

The Art of Photography => User Critiques => Topic started by: tonysmith on July 04, 2009, 02:38:47 pm

Title: Day Lily
Post by: tonysmith on July 04, 2009, 02:38:47 pm
Maximum zoom, hand held, on a windy afternon

[attachment=15107:Day_Lily.jpg]

Comments appreciated
Title: Day Lily
Post by: John R on July 04, 2009, 02:51:27 pm
It looks very nice. But, don't know if you realize it, I can see pixelation, so I don't know quite what you did to arrive at this kind of result. Perhaps you oversharpened it. One can destroy bokeh when using excessive amounts of sharpening.

JMR
Title: Day Lily
Post by: cmi on July 04, 2009, 03:06:18 pm
JPEG artifacts, compression is set a bit high. Doesnt disturb me.
Title: Day Lily
Post by: Ed Blagden on July 04, 2009, 03:16:29 pm
Good technique and good equipment (I guess this is what you were trying to show).  However the shot itself doesn't do too much for me - the lighting is much too harsh for my tastes.  Also agree with the comment about compression: apart from the pixelated background there are some horrible artefacts around the outline of the flower - I think this is something to do with jpeg compression.  

Ed
Title: Day Lily
Post by: tonysmith on July 04, 2009, 04:25:12 pm
Ed is correct that I was looking for technical not aesthetic input. Your eyes are better than mine - I had to look up "pixelation" and now think I see it in the flower but not the background, and still am not sure what is meant by (and can't see )"jpeg artefacts". Could you help me by pointing out these issues more directly?

Here is another image taken about the same time but with less sun. I had not submitted this one because I thought the focus not so good. This is the unadjusted RAW saved as jpg with minimum compresion consistent with maximum file size for the site. Do the problems persist? is the light better?

Actually, I find this rather bland but value your opinions nevertheless.

Thanks for your input.

[attachment=15111:Day_Lily_3.jpg]
Title: Day Lily
Post by: shutterpup on July 04, 2009, 04:46:53 pm
On #2, I don't see a point of focus; it is soft. However, the artifacts around the edges of the flower and the stem look to be nonexistent and the pixelation is not present.
Title: Day Lily
Post by: cmi on July 04, 2009, 05:06:08 pm
Quote from: tonysmith
Ed is correct that I was looking for technical not aesthetic input. Your eyes are better than mine - I had to look up "pixelation" and now think I see it in the flower but not the background, and still am not sure what is meant by (and can't see )"jpeg artefacts". Could you help me by pointing out these issues more directly?

Here is another image taken about the same time but with less sun. I had not submitted this one because I thought the focus not so good. This is the unadjusted RAW saved as jpg with minimum compresion consistent with maximum file size for the site. Do the problems persist? is the light better?

Actually, I find this rather bland but value your opinions nevertheless.

Thanks for your input.

Tony,

jpeg is a lossy image compression algorithm. It leaves out information wich is not important to the human eye first, thereby enabling bigger compression. The more you compress, the more visible the loss. To make it obvious, crank up your quality slider all the way down, then you will clearly see the artifacts around edges, and the blocky artifacts in smooth areas wich are characteristic for jpeg. Once you know what to look at its obvious. In your first image its quite visible. The new image on the other hand is quite soft as you say and for me not as interesting as the first. (Ok I think the first is also not that spectacular, it is "just" a snapshot of a flower, of a nice flower that is.) The jpeg quality here in the last one is fine. Generally I go for say 80-90% jpeg quality when submitting for web.

Christian