Some people (acquaintances) said I could sell some of my pics and I've gotten published in on-line aviation newsletters and/or websites (total rewards = 2 baseball caps). The TC I was talking about was the Smart Teleconverter button on the back of the camera (digital in-camera enlargement). I've never used an optical behind-the-lens unit. I've dabbled in macro or landscape, but 95-98% of my annual images are from aviation-related activities. If you like, check out my Oshkosh albums on my FB page.

Humm, part of a carryover of the Aphasic language resulting from ergot poisoning** ... the mold... in the wheat that made their bread.

For those of you who do not know: " Aphasia is a condition that robs you of the ability to communicate. It can affect your ability to speak, write, and understand language, both verbal and written. Aphasia typically occurs suddenly after a stroke or a head injury or certain poisons. " No one in their right mind can pronounce those words.

** Ergot has an interesting history:
http://www.tootlafrance.ie/features/the-idyllic-french-village-that-went-insane

BebuLamar is correct about camera shake being magnified, the longer the zoom, hence the need for a stable platform or tripod. Sony’s Clear Image Zoom, or CIZ attempts to effectively double the zoom range, digtally, without perceptible loss of image quality. It does a fair job, but if you crop and image to 100% or more, you can see ever so slight loss of IQ. Digital zoom, however, immediately results in loss of IQ, and the farther you zoom, the worse it gets. To add to the problem, at very long zoom ranges, atmospheric anomalies like heat waves, dust particles in the air, etc. This is all magnified at long zoom ranges.

I don’t know if this answers your question, at all, but in short, there will be more apparent camera shake as you zoom, and the more you zoom, the more apparent it is, since everything is, in essence, magnified. An image taken at max zoom, in your case, 600mm, will be degraded if you crop it to twice its size, as if it were taken at 1200mm eq.

I have used a variety of macro lenses and cobbled together rigs seeking a reasonable alternative to expensive, new macro lenses. The 1st lens I bought for my a6000 several years ago was the Sigma 60mm f/2.8 for E mount ($239.) I noticed that it was impressively sharp and eventually tried it with extension tube, Canon 500D close-up attachment and was not particularly impressed so moved on to hunt for a better solution.

Now I thought my technique has improved so perhaps a retest would be appropriate. I Tested the 60mm Sigma and the Canon EF-s 60mm f/2.8 macro on the same target. The Sigma appeared to be noticeably sharper as well as brighter (Will post about that later.) So I took the Sigma with a vintage Canon 240 C-8 in place of the 500D. Here’s the result with a very cooperative subject.