Just a brief clarification here..... the TC magnifies the image from the first lens. In itself it ads no new information.
However two other things happen. Detail too fine for the sensor to resolve, can be magnified to the point where they are accurately portrayed using the given sensor density. Same as thing that are invisible to the human eye become visible under a microscope, the 1.4 converter has the ability to make details invisible to the sensor, viable, through magnification.
So more detail in the magnified image is possible based on he resolving power of the lens and the quality of the sensor.
For example, say your sensor is 10 lines. It will portray accurately 5 black and 5 white lines. But what if you have 14 black and white lines, 7 black-7 white. Your 10 line sensor can't resolve that, it doesn't have enough resolution. Put the 1.4 TC on your lens and the sensor now sees only 10 lines. The sensor is capable of resolving 5 black and 5 white ones. You actually can get an accurate image of a reduced section of the target, because you used the TC. The information was always supplied by the lens. But with a 10 line sensor, 14 black and white lines cannot be accurately portrayed, 10 can.
This is I know horribly over simplified. But it should give you some understanding of how a TC can provide a clearer image, than simply blowing up the original target to the same size. Any detail that could be resolved by the sensor with the TC, that is small enough to be unresolvable by the sensor without the TC will be lost if the TC isn't used. It's possible wo use picture for your comparison that have no unresolved detail without the TC. But in my own tests, I have never seen that happen. IN my test, so long ago I can't find it, Resolving power was in keeping with the focal length of the lens. Whether or not a TC was used, made no difference. The above explains why I think that happens.
The other way these details could theoretically be picked up could be by using smaller pixels. The example would be putting my A-400 on Q to give myself the equivalent of 1800 mm. Would I resolve things that couldn't be seen using the same lens on my K-5. Of course I would.... would the picture be as crisp? I don't know, but looking at the best of the Q images I've seen using long lenses, they are as good a s APS-c
HeInrich Lohman's Ground Squirrel... 200mm lens on a Q
https://www.pentaxforums.com/forums/12-post-your-photos/321606-nature-just-so...e-gophers.html
AN image from a Panasonic FZ1000 1 inches sensor..
If you calculate the size of these pixels and realize that the FZ1000 is 20 MP on a one inch sensor that's 1/4 the size of an APS-c cranks out this kind of detail, you quickly realize, it's going to be a long time before good 1.4 or even 2x converters don't ad detail. This FZ1000 camera can produce 2700 lw/ph on a 20 MP sensor, the K-3 produces 2800 on an APS-c sensor. The average lens can be magnified quite a lot, before it stops providing new information.
IN fact if you think of microscopic dust and stuff, there is simply no point at which more magnification doesn't produce more detail. Magnification makes things visible which were previously invisible. This is not a magic class of product that renders magnification meaningless, and to argue against a TC is pretty much to argue against magnification.
Last edited by normhead; 05-23-2016 at 07:51 PM.