Sony DT 18-250 f3.5-6.3 Dissapointed User

[videoguy]

To Bakubo. Sorry I almost forgot to post your request of cropped pics. All samples submitted were shat against a green chromakey background, the white is added as a new background (the color of type of scene used as a background does NOT make the line go away).
1. Unaltered - without color difference key (to clean up the background keying).
2. Altered - with " "
3. out of camera -JPEG fine- DRO+ (no additions).
4. different pic with blue shirt & skin color.

What I can see is that there is a edge difference, only not so visible because of the not white background. The left is cleaner than the right side of the subject shirt in all samples. This reminds me of a TV scan line "ringing" on the right side of bright objects.

videoguy

[videoguy]

Here's the fourth pic (sorry about the 3-pic rule this time).

videoguy

[David Kilpatrick]

In Photoshop, after doing selection and alterations of this type (assuming you use layers), you may need to use the commands under 'Matting' to remove fringes.

I did not realise you were using green chromakey. To use chromakey, all sharpening must be entirely disabled - that includes going into the camera menu and setting the lowest softness level (-3 or whatever) to eliminate artificial fringes. DRO etc must of course be off as they can create edge effects, and you must NEVER use the 'Recovery' slide in Photoshop. Also, you must not use the Lens Correctin commands 'Defringe All Edges' or 'Highlight Edges Only' - but you can use CA correction values (without defringe). And at the same time, try to work with no ACR noise reduction, especially colour NR.

There is a specific reason for this. Colour NR at strong levels creates colour clouds rather than pixels, and these blurred clouds of colour which underly the luminance values (image detail) can spread into other colours very easily - across edges. They then make chromakey difficult to achieve cleanly.

David

[alphaPDX]

I was happy with my Tamron 18-250, but then I picked up a Quantaray 18-200 (pronounced "Sigma" ) for under $150US brand new. It works nearly as well in every respect, and slightly better in a few (marginally faster focus, slightly better bokeh to my eye) and definitely lighter thanks to the 200mm top end. My copy can be considered an 18-180 f/3.5-5.6, only above 180mm is it f/6.3 max. These things are abundant online at auction thanks to the Ritz reductions in the USA. I sold the 18-250 with reluctance, but am happy with my decision; maybe you can find a Sigma-esque 18-200 with a good return policy & see what you think.