# what causes "glowing"?



## Ganoderma (Aug 16, 2009)

once again, i am having troubles lol.

playing around some more with the sigma 70-300 lens (aka "the cheapy" as my wife calls it).

i am finding myself getting what i want but most of the pictures have this bluing glow type thing to them.

here are some pics i just took now to show.  mind you they were hand held at night under medium fluorescent lighting, but the glow happens a fair bit in different situations, even with tripod/remote stillness.

example 1 cactus spines
iso 200
 f/5.6
 263mm
 1/20sec
used flash.









example 2 cactus seeds.
iso 200
f/5.6
263mm
1/20sec
used flash....thinking this has to do with the problem...?





cropped







another question.  i used a white lit box (used for growing seedling plants) and took a pic of various cactus....i used tripod/remot and mirror lockup and took dozens of pics and still not super fine detail.....i am at a loss now 
i see some excellent pictures of say a bumble bee, and the hairs are in nice detail on said bee....but i cannot (with this one lens) seem to get that kind of detail.

example
iso 100
 f/6.3
 1/25sec






any thoughts as to what im doing wrong?


----------



## BoostedHoo (Aug 16, 2009)

are you using external flash or on board pop up flash?


----------



## Josh66 (Aug 16, 2009)

The glowing is CA - Chromatic Aberration.
Chromatic aberration - Wikipedia, the free encyclopedia


----------



## Sw1tchFX (Aug 16, 2009)

It's not chromatic aberration, it's spherical aberration. It's common on wide aperture lenses like 50mm f/1.4's, 1.8's, and you can see it when you stop any lens down to it's minimum aperture. 

Spherical aberration - Wikipedia, the free encyclopedia


----------

