Tele-converter or DX mode

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bleirer said:
I like the quote in big bold letters around 10:15. "All other factors equal - the smaller sensor will have the shallower depth of field."

Good video, worth watching from the beginning. He goes on to explain equivalency and crop factor and why once adjusted by physically moving farther away to fill the sensor with the same size subject the dof increases (because of being farther away). However we have been talking about staying in the same place and by cropping effectively reducing the size of the sensor. At least that's how I see it.
Click to expand...
This is the crux of the confusion/misunderstanding which causes so much discussion on this topic. Many people don't understand the concept of "all things being equal" or the need to compare things at the same FOV and output size.

Edited: forgot to mention output in original post.
 
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NorthernFocus said:
This is the crux of the confusion/misunderstanding which causes so much discussion on this topic. Many people don't understand the concept of "all things being equal" or the need to compare things at the same FOV.
Click to expand...

There are a lot of moving parts. The several photography life articles seemed to explain it very well.
 
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I had a wallhanger shot with a z20mm.
My wife complained about the distance hills are too small, and we should re-capture that scene with a 50mm.

I posted the picture here on BCG, and someone (I forgot who it was) “cropped it” to match the FOV of a 50mm.
Suddenly the distance hills appeared bigger!

Its all eye perception and expectations.

I remember relying on PhotoPills app to calculate DOF for use in our portrait studio. I found the calculations and actual results to be completely wrong!
It was all due to our own expectations in the way we envisioned and perceived the image on screen and on print. Heck, we dared to capture f/1.2. Shots that “looked” great! But according to the app, we had zero DOF…

To answer the question in this topic, TC vs. cropping? It depends!
If I need the light and lower ISO, I would DX. If I need the reach with enough light, I would use a TC.

I think, The lost stop of aperture recorded in the image when using a TC, isn’t right. Why? Because it’s that same amount of light ON THE SUBJECT when DX’ing. And its not like I would stop down the bare lens.

f/6.3 bare lens minus 1 stop = f/9 DOF.
f/6.3 plus a 1.4 TC
OR
f/6.3 bare lens plus DX/crop in post = f/6.3 DOF!
ONLY light and noise are equivalent to f/9.
 
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