Canon 24TS or use the Canon 17 + Canon 1.4 Tele extender on Sony aR7II?

[Lust4Life]

Recently purchase AR7II and have mated it to the Canon 17TS with the Metabones adapter.
Images look excellent.

Now, take the 17TS, add the 1.4 Canon Tele Extender and you have 23.8/24mm TS lens equivalent.

Has anyone done this?
If so, results?

It sure would be a lot cheaper and far less weight in my backpack if it gives excellent results.

[David Eichler]

Depends upon the ultimate use. The 17mm ts-e with the 1.4x converter yields quite high quality reaults, but still not quite as good as the current 24mm ts-e.

[maddogmurph]

My understanding of tele converters in general is sharpness loss. While it's estimated that you might only lose 5% sharpness with such a setup, I think you also might find that you'll encounter issues with abjurations potentially. That being said, buying a 1.4tele is a hell of a lot cheaper than buying another lens and most people won't care or notice that type of sharpness loss unless you're going 40x60

[David Eichler]

I will add that I own and have used this equipment professionally to photograph architectural subject matter. While not the optimum available equipment for achieving 24mm with movements (that is the 24mm ts-e II), it can deliver very high quality results for demanding applications.

[alan_b]

You'll probably still want the 24 as it takes filters, and you can use it with the 1.4x to get a TSE-35. 

As David said, you can still get high-quality results with the TC, but will need to be more careful with focus.

[Lust4Life]

You'll probably still want the 24 as it takes filters, and you can use it with the 1.4x to get a TSE-35. 

As David said, you can still get high-quality results with the TC, but will need to be more careful with focus.

That makes a lot of sense - use the 24 to get close to a 40, as I have used the 45 TS in the past and did not find it to be Canon's Best!

Thanks folks for your input.