A Mount with Phase Detection or E-mount? at DVinfo.net

Dave Allen · February 21st, 2013, 01:27 AM

For those who wish to use autofocus frequently, which route would you suggest and why, the A-mount lenses with the LEA2 adapter (you lose 1 stop of light I hear) so you get the allegedly superior Phase Detection focusing, or the E-mount lenses and their allegedly inferior face detection and supposed autofocus drift issues on moving subjects.

Thanks!

Chris Medico · February 21st, 2013, 06:06 AM

I considered both and decided to stay with E. The issue with A is also that the AF only works at specific iris settings. That was the dealbreaker for me.

Lee Faulkner · June 4th, 2013, 05:45 PM

Quote:

Originally Posted by Chris Medico

I The issue with A is also that the AF only works at specific iris settings. .

Do you have more details about this limitation please? A link maybe?

Thanks

Lee

Chris Medico · June 4th, 2013, 07:19 PM

Sure. Check out the page here - http://www.bhphotovideo.com/c/product/819768-REG/Sony_LA_EA2_A_Mount_Lens_to_NEX.html
Look down at the bottom to #3. It reads:

Aperture setting for video capture is fixed at the maximum aperture of the lens or f/3.5, whichever is lower (AF-C).

Lee Faulkner · June 5th, 2013, 06:26 AM

Thanks!

I think I get it now ... in video based continuous AF the lens needs as much light as possible, thus opens up ( like it would on a still camera ) and has to stay that way for the duration of the shot.

I appreciate the nudge...

Best

Gabe Strong · June 5th, 2013, 08:08 AM

Actually it restricts you from opening the lens up all the way if you have a fast lens.
Say you have a F2.8 zoom. You must shoot at F3.5. Say you have a fast 1.4 prime.
You must shoot at F3.5. If you want to use autofocus in both cases you can't open
the lens up.

Chris Medico · June 5th, 2013, 08:19 AM

And if you want to shoot at 5.6 to make it a bit easier for the autofocus to keep up in a sporting event with plenty of light or to hold on to more background. You can't do that either. It is 3.5 or nothing (assuming a 3.5 or faster lens).

Lee Faulkner · June 6th, 2013, 06:51 AM

Got it ... could be a bit confusing if you weren't ready for it!

But when required its workable...

Best

James Barbosa · June 6th, 2013, 11:42 AM

I've never really had problems with my LA-EA2. With my weddings and on the move shoots it's been more help than anything else. I mostly use the Sony Zeiss 24-70 2.8 with it and the extra stop is not that big a deal for me. Pushing the iso up a stop works in its place.

The thing I love about it, is that the focus is so fast and silent with that lens that its hard to imagine it's as accurate as it is. But it works like a charm.

If only taking into account auto focus, the A mount is a better option. Also a wider range of lenses to choose from than the E mount.

I'd say if you can, try them both out first and decide for yourself.

Dave Allen · June 17th, 2013, 12:39 AM

I tried some e-mounts, including the kit lens, and I was not impressed at all with its autofocus ability Slow and hunts a bit. Even the kit lens footage at NAB had out of focus instances.

I tried a quality A mount and LEA2 adapter and was pleased, so the latter is the route I went.

Bill Kerrigan · June 17th, 2013, 06:58 AM

I own both the LEA2 and E mount lenses.

I've had amazing success using Face Detection and the kit lens.
I'm from a film background and normally use an assistant.
The FD system has given me a usable shot the 1st time, which would have taken 10 tries with the assistant.
When I'm shooting a documentary... and I don't know what's going to happen next, I'll use the kit lens.

I've rarely use Phase Detection because of it's restrictions.
But after reading these posts... I'm looking forward to giving PD a second try.

Bill Kerrigan
Montreal, Quebec, Canada
http://www.kerrigan.ca
http://indiecameras.com

February 21st, 2013, 01:27 AM	#1
Dave Allen Major Player Join Date: Apr 2008 Location: Boston Posts: 497	A Mount with Phase Detection or E-mount? For those who wish to use autofocus frequently, which route would you suggest and why, the A-mount lenses with the LEA2 adapter (you lose 1 stop of light I hear) so you get the allegedly superior Phase Detection focusing, or the E-mount lenses and their allegedly inferior face detection and supposed autofocus drift issues on moving subjects. Thanks! __________________ Dave -

February 21st, 2013, 06:06 AM	#2
Chris Medico Inner Circle Join Date: Aug 2006 Location: Efland NC, USA Posts: 2,322	Re: A Mount with Phase Detection or E-mount? I considered both and decided to stay with E. The issue with A is also that the AF only works at specific iris settings. That was the dealbreaker for me. __________________ http://www.LandYachtMedia.com

June 4th, 2013, 07:19 PM	#4
Chris Medico Inner Circle Join Date: Aug 2006 Location: Efland NC, USA Posts: 2,322	Re: A Mount with Phase Detection or E-mount? Sure. Check out the page here - http://www.bhphotovideo.com/c/product/819768-REG/Sony_LA_EA2_A_Mount_Lens_to_NEX.html Look down at the bottom to #3. It reads: Aperture setting for video capture is fixed at the maximum aperture of the lens or f/3.5, whichever is lower (AF-C). __________________ http://www.LandYachtMedia.com

June 5th, 2013, 06:26 AM	#5
Lee Faulkner Regular Crew Join Date: May 2005 Posts: 35	Re: A Mount with Phase Detection or E-mount? Thanks! I think I get it now ... in video based continuous AF the lens needs as much light as possible, thus opens up ( like it would on a still camera ) and has to stay that way for the duration of the shot. I appreciate the nudge... Best

June 5th, 2013, 08:08 AM	#6
Gabe Strong Major Player Join Date: Jul 2002 Location: Juneau, AK Posts: 814	Re: A Mount with Phase Detection or E-mount? Actually it restricts you from opening the lens up all the way if you have a fast lens. Say you have a F2.8 zoom. You must shoot at F3.5. Say you have a fast 1.4 prime. You must shoot at F3.5. If you want to use autofocus in both cases you can't open the lens up.

June 5th, 2013, 08:19 AM	#7
Chris Medico Inner Circle Join Date: Aug 2006 Location: Efland NC, USA Posts: 2,322	Re: A Mount with Phase Detection or E-mount? And if you want to shoot at 5.6 to make it a bit easier for the autofocus to keep up in a sporting event with plenty of light or to hold on to more background. You can't do that either. It is 3.5 or nothing (assuming a 3.5 or faster lens). __________________ http://www.LandYachtMedia.com

June 6th, 2013, 06:51 AM	#8
Lee Faulkner Regular Crew Join Date: May 2005 Posts: 35	Re: A Mount with Phase Detection or E-mount? Got it ... could be a bit confusing if you weren't ready for it! But when required its workable... Best

June 6th, 2013, 11:42 AM	#9
James Barbosa New Boot Join Date: Sep 2012 Location: Mansfield, Ma Posts: 16	Re: A Mount with Phase Detection or E-mount? I've never really had problems with my LA-EA2. With my weddings and on the move shoots it's been more help than anything else. I mostly use the Sony Zeiss 24-70 2.8 with it and the extra stop is not that big a deal for me. Pushing the iso up a stop works in its place. The thing I love about it, is that the focus is so fast and silent with that lens that its hard to imagine it's as accurate as it is. But it works like a charm. If only taking into account auto focus, the A mount is a better option. Also a wider range of lenses to choose from than the E mount. I'd say if you can, try them both out first and decide for yourself.

June 17th, 2013, 12:39 AM	#10
Dave Allen Major Player Join Date: Apr 2008 Location: Boston Posts: 497	Re: A Mount with Phase Detection or E-mount? I tried some e-mounts, including the kit lens, and I was not impressed at all with its autofocus ability Slow and hunts a bit. Even the kit lens footage at NAB had out of focus instances. I tried a quality A mount and LEA2 adapter and was pleased, so the latter is the route I went. __________________ Dave -

June 17th, 2013, 06:58 AM	#11
Bill Kerrigan Regular Crew Join Date: Dec 2008 Location: Montreal, Quebec, Canada Posts: 92	Re: A Mount with Phase Detection or E-mount? I own both the LEA2 and E mount lenses. I've had amazing success using Face Detection and the kit lens. I'm from a film background and normally use an assistant. The FD system has given me a usable shot the 1st time, which would have taken 10 tries with the assistant. When I'm shooting a documentary... and I don't know what's going to happen next, I'll use the kit lens. I've rarely use Phase Detection because of it's restrictions. But after reading these posts... I'm looking forward to giving PD a second try. Bill Kerrigan Montreal, Quebec, Canada http://www.kerrigan.ca http://indiecameras.com Last edited by Bill Kerrigan; June 17th, 2013 at 10:29 AM.