Diffraction-Limited-Aperture (DLA): limitations with Hi-Res bodies for landscape and wildlife with teleconverters

[Reciprocum]

Until I read this review

Sony Alpha 1 Review

Is the Sony Alpha 1 right for you? Learn all you need to know in The-Digital-Picture.com's review!

www.the-digital-picture.com

I was completely unaware that there was such a thing as DLA

Diffraction-Limited-Aperture

What is Diffraction Limited Aperture (DLA)? And why you need to know what your camers's DLA is.

www.the-digital-picture.com

Now, according to their table, DLA (on A1 for example) starts to become an issue past f6.7 (sooner for A7Riv) ...

I remember f11 being the go-to aperture for landscape photography (to get all in focus) and high-res bodies also being a favourite of landscape photographers. Isn't this contradictory ? Would they best be doing focus stacking at the maximum DLA aperture for their sensors ?

Now for birding/wildlife/sports using 200-600mm + TC with an A1/A7R4 body focus stacking is not an option thus it means that with that lens+TC combo one is always shooting at suboptimal (DLA-wise) f-stops and the only way to get max IQ (while using TCs) is really to get the expensive 400mm f2.8 and 600mm f4.0 primes ...

Anyone giving even a thought to DLA limits on their day-to-day shooting routine ?
I for one, with the A1, in the studio, will remember myself not to go over f7.1. With my previous 7M3 I never worried (or new) about DLA and sometime shot f9 in studio, wich fortunately (and by mere luck) was still bellow the DLA limit for the 24mpx sensor.

 

[Ziggy]

My understanding is that TCs magnify the image - so DLA shouldn't be worse.

 

[Ziggy]

Until I read this review

Sony Alpha 1 Review

Is the Sony Alpha 1 right for you? Learn all you need to know in The-Digital-Picture.com's review!

www.the-digital-picture.com

I was completely unaware that there was such a thing as DLA

Diffraction-Limited-Aperture

What is Diffraction Limited Aperture (DLA)? And why you need to know what your camers's DLA is.

www.the-digital-picture.com

Now, according to their table, DLA (on A1 for example) starts to become an issue past f6.7 (sooner for A7Riv) ...
View attachment 8322

I remember f11 being the go-to aperture for landscape photography (to get all in focus) and high-res bodies also being a favourite of landscape photographers. Isn't this contradictory ? Would they best be doing focus stacking at the maximum DLA aperture for their sensors ?

Now for birding/wildlife/sports using 200-600mm + TC with an A1/A7R4 body focus stacking is not an option thus it means that with that lens+TC combo one is always shooting at suboptimal (DLA-wise) f-stops and the only way to get max IQ (while using TCs) is really to get the expensive 400mm f2.8 and 600mm f4.0 primes ...

Anyone giving even a thought to DLA limits on their day-to-day shooting routine ?
I for one, with the A1, in the studio, will remember myself not to go over f7.1. With my previous 7M3 I never worried (or new) about DLA and sometime shot f9 in studio, wich fortunately (and by mere luck) was still bellow the DLA limit for the 24mpx sensor.

Here's a field test of the impact of diffraction on sharpness:

How Much Does Lens Sharpness Matter?

Photographer Alan Adler looks into how much we can actually perceive the sharpness differences in lenses of various qualities.

petapixel.com

 

[garuda]

My understanding is that TCs magnify the image - so DLA shouldn't be worse.

Ziggy, I know you're the man, and I don't want to stir the pot, but maybe I have to adjust my understanding.

I thought by the Fresnel principle (cylindrical aperture), the distance betw the object (source) and the aperture determines the distortion (diffraction) on the other side of aperture. In Fraunhofer, the aperture plane is infinite, but Fresnel is finite. So wouldn’t a TC change the formula by extending the distance?

Maybe I'm wrong in my understanding? I'm on the verge of deciding on a 2x TC for my 200-600, but I'm not a fan of shooting at near wide open apertures for many of my preferred shots.

 

[AlphaWorld]

Bear in mind that it’s not a hard limit. It’s not f/7.1 is OK and f/8 is completely unusable. It’s a gradual transition, where things get a little softer each step you take.