Full-frame or APS-C lenses for video on A7RII

[Emptymind]

I am trying to work out the advantages or cons of using Full-frame lenses as against 35mm lenses when shooting video with the A7RII. Beside the crop factor what other considerations are there? In the end it's a decision on wether I buy a fresh set of FE lenses....

[that1guyy]

Seems dumb to buy crop lenses for a full frame body

[Gilgenberg]

the FE lenses are better than the sony aps-c SEL lenses even on aps-c body´s

[delewin]

If you were only using the A7RII for video and that video was the 4K cropped censer mode then and only then would it make any sense to use APS-C lenses on this camera.

 

For ALL other uses this camera was made to perform, the full frame lenses will give you a far superior result.

 

Is your interest exclusively video?

 

What lenses do you currently own?

 

After knowing exactly what you currently have and what you wish to achieve, the good people of this Forum can give you the benefit of their experiences.

 

Regards,

David

[Emptymind]

I have some nice Canon lenses which I will use an adapter that I just ordered and my Sony glass is the Sony 18-105mm f/4 and Sony 16-70mm f/4 and a few primes but no full frame lenses. I shoot 75% video.

 

I'm not against changing to FE full frame lenses - though I would prefer f/2.8 as against f/4 on the zooms.

 

Also this is for my lightweight travel setup - not regular work filming. So I am trying to get by with two nice zooms and maybe one low-light prime in total.

[tellure]

I have a bit of experience here as I own an A7R2, I am primarily interested video, and I also own a several APS-C E-mount lenses (and now one FE-mount lens).

 

Here's a quick summary of what I've found in shooting with APS-C vs. FE mount so far, again assuming your primary use is shooting video.  If you are really interested in stills then obviously you are giving up a ton of resolution on the A7R2's 42MP sensor by going into crop mode.

 

1) Some APS-C E-Mount lenses can offer good quality with reduced weight / size compared to FE.  For example I have the Sony 10-18mm f/4 wide-angle zoom (which also works on full frame without vignetting starting around 14mm BTW); it's been tested a bunch on full-frame and offers pretty nice quality with a much smaller size and much less weight than the comparable FE lens (Sony 16-35mm f/4).

 

2) FE lenses give you more flexibility for focal lengths.  I recently bought the Zeiss 55mm 1.8 FE and really like the fact that when shooting video I can turn it into an 82mm lens with a few menu button clicks (which should really be one click once Sony gives us the ability to map Super35 toggle to any button).  This flexibility is huge!  1.5x multiplier on all your focal lengths without any loss in resolution! (for video).

 

3) Full frame gives shallower depth of field of course, so a more filmic look if you're after it, as most of us are.

 

4) Super35 video mode on the A7R2 has more rolling shutter, so if you are using APS-C lenses you are stuck with that.

 

5) Super35 mode has no pixel binning, however, so less moire.  I haven't really noticed the moire in any real-world footage I've shot at full frame yet though.

 

6) APS-C lenses are cheaper, so if budget is an issue you can definitely get a wider lens collection much more cheaply in the APS-C space

 

7) When shooting time-lapses there is a big advantage to shooting full-frame, and that's that you can shoot 42MP stills (RAW, ideally), and then use various software (e.g. Panolapse) to zoom in/out and pan around the scene, creating a much more dynamic time-lapse, all while maintaining 4K output resolution.  I've shot time-lapses on my old A6000 and they can be really great so I'm looking forward to trying this out.  Here's an example of a guy doing this with the original Sony A7 (although only for 1080p output).

 

 

Overall after using my APS-C's and my new 55mm FE lens for a while I think I'm going to shift mainly over to full-frame, mainly for the focal length flexibility which is huge.  I might even end up replacing my beloved Zeiss 24mm 1.8 APS-C, which is a great lens, for the Zeiss FE 35mm 2.8, which is actually smaller and lighter than the 24mm and has the same focal length and depth of field.

 

I am still interested to see what the future brings for APS-C E-mount lenses though.. if someone manages to come out with a great quality compact fast zoom for APS-C E-mount I might buy one. For example if Sigma made a smaller and lighter version of their 16-35mm 1.8 APS-C SLR lens. I would love to have that as a good general-purpose zoom instead of whatever big and heavy 24-70 2.8 zoom Sony ends up coming out with for FE mount.  I'll also probably still keep my 10-18mm f/4 since the weight and size advantage over FE is big and I'm trying to keep my kit light for traveling.  

 

Hope that helps!

[Emptymind]

That was helpful and similar to my thoughts. I think I will add the Sony 10-18mm f/4 for video to pair with my Sony 18-105mm f/4. Thats my video lens done for travelling light. I am thinking to add full frame primes slowly (due to expense). My first being the Sony 35mm F2.8 or the 55mm 1.8. and go from there. I have a few good Canon lenses and need them for my larger video camera that is FE mount so its a plus these can be used in crop mode with an adapter. Cheers.

[dcolak]

the FE lenses are better than the sony aps-c SEL lenses even on aps-c body´s

 

I have 50mm 1.8 apsc and 55mm 1.8 FF on my A7RII.

 

I don't see anything better on FF 55mm compared to 50mm APS-C lens.

 

The APS-C lens has less chromatic aberrations and to my eye looks better.

[joema]

I am trying to work out the advantages or cons of using Full-frame lenses as against 35mm lenses when shooting video with the A7RII. Beside the crop factor what other considerations are there? In the end it's a decision on wether I buy a fresh set of FE lenses....

I know you mentioned lightweight travel. Except for that stipulation, Sony has a great lens for video - the 28-135 f/4 PZ. We use that for documentary video and it works great. It has power zoom so you can do that smoothly. The focus ring switches between manual and auto focus by just pulling or pushing it -- without moving hand off the lens you can switch focus modes. The Super 35 mode of the A7RII gives the 28-135 about 200mm reach on the long end. Optically it's not quite equal to my Canon 70-200 f/2.8 IS II, but it's very good and for video use the other features compensate. Another big advantage is there are variable ND filters that fit under the lens hood. It is difficult to find any other lens with a hood that fits over a variable ND filter.