Sony A7RIII improper to dynamic studio portraiture?

[Deeliciouz]

Hi all! I have been a canon user for years and started with the 5d mkII (85mm f1.8 prime and 24-105 f4 L) especially involved in dynamic (street photography) and lowlight photography in the first place, i.e. stage photography (in harsh conditions -no flash, low light, handheld, comedians performing live...) then I started to specialize in staged studio portraiture (2× Elinchrom 500w). I also developped DOP skills in a cinema project and used the Canon 5dmk2 in that respect. 

The reasons for me to shift to Sony are:

1. Effective eye-tracking autofocus (is it me or did Canon really intend to commit commercial suicide not implementing that feature????)

2. Tack-sharpness and quick auto-focus

3. State-of-the art technology in the expert range outperforming canon 5ds and 6ds at a reasonable price tag. 

Now, three salesmen advised the sony A7III as a rational option for dynamic studio photography, which I do agree with. The point is I am really hesitating with the more expensive Sony Alpha7RIII since I like large format printings and super sharp portraits. I realize 42mp pictures will get my hard drives, CPU and retouching process busy.

Suprisingly, two salesmen out of three told me the AlphaRIII was not proper to in-motion subject studio photography since the 42mp resolution was slower to process and would consequently generate inaccurate rendering/softness requiring to double the speed to reach tack-sharp shots (eye-focused) even with studio strobe.

In short, SonyAR3 for POSED portraiture, macro, packshooting, stills, architecture, landscapes... only. 

My basic settings for studio are: 

1/125th at 100 ISO. Subjects are not running, not bouncing, not headbanging on 200 bpm speed metal music. They just move as they would do in normal life, somewhat slower...

 

I don't get it since that statement would mean the A7R3 could then not be able to deliver proper 42mp tack-sharp shots (full view) below 1/200th unless I'd ask my models to freeze??? Otherwise 'the expected softness/blur' will be quite noticeable and will ruin your work, given the super high resolution' they said.  

 

After a few questions, the salesmen admitted not being experienced in studio (were more 'macro, packshooting, nature...). 

What do you guys think? How well does the A7R3 perform in dynamic studio photography? How does it behave and compare with the A7R3 in that respect?

Thank you so much in advance for your help! 

[Pieter]

I'm not a studio photographer myself but it is true that you'll need a faster shutter speed for tack sharp images (at pixel level) if you have a higher resolution sensor. When printed at the same size however, it shouldn't matter.

I guess it would mess up your workflow but if you'd edit a 42mp RAW and downsample it into a 24mp jpeg, you'd end up with similar or higher sharpness than if the original picture were shot at 24mp. In other words, you'd loose nothing by taking a higher mp shot as a starting point.

[Deeliciouz]

Thank you for your reply. So if I get it right, say I'd work with a 1/200th with the 24mp sony A7III. If I ever shift to the 42mp A7RIII (same lighting conditions, same aperture and iso settings), I'd have to increase the shutter speed to, for instance, 1/400th to 'freeze' every pixel and achieve tack-sharp large prints. If this is correct, the point is the shutter speed treshold with studio strobes is usually 1/200th. So for very large ultra sharp studio portrait pictures, the Sony A7III seems to be more adequate. Is my thinking correct? 

[Pieter]

Yes and no. The A7Riii has roughly 30% more pixels horizontally and vertically. For the same print size (say the maximum you could do with your A7iii), sharpness will be equal with both cameras. The A7Riii just has the potential to print 30% larger if you manage to get a sharp picture. Since the pixels are 30% smaller horizontally and vertically on the A7Riii you'll roughly have 30% more motion blur per pixel. To counter this, you'd need a 30% shorter exposure. If you run into the maximum sync speed (1/250 sec for both cameras) indeed the headroom is limited on the A7RIII. But freezing motion blur is not a true or false criterion: it totally depends on the speed of motion you're trying to capture. When always shooting at the maximum sync speed and you reject all pictures with the least bit of motion blur per pixel, indeed the A7iii will get you slightly more keepers. But like I said in my previous post: if you downsample the 42mp pictures to 24mp, both cameras will show the same amount of motion blur.

In my opinion this is all false reasoning: might as well get a 12mp A7Siii then when it comes out: this camera will have even larger pixels than the A7iii so much less motion blur per pixel...

[Deeliciouz]

Thank you Pieter for your in-depth explanations! I really appreciate.

I should have mentioned similar settings for a similar shot (subject moving at the same speed, same distance, same light set etc.)

Whatever! It now makes sense. I was not even aware of that relation between pixel size and motion blur. This is probably why some studio photographers like to use medium-format cameras. I mean apart from all the advantages of a medium fomat cam, the 50mp+ of a Pentax 645 would be obviously larger than the 42mp of a Sony a7r3 since the sensor size is larger and so for equal shutter speed (and so on) they would be easier to 'freeze'... 

I now understand better the strengths of the Asiii. Say I'd have to shoot comedians lowlight handheld, that camera would allow me to achieve increased sharpness compared to the sony ariii... I figured it was just because the higher the pixel concentration, the smaller the photosites and thus the higher the noise (or something like that).

Thank you again, mate!

 

[Pieter]

Indeed, on pixel level the noise and motion blur on the 42mp A7RIII images will be much worse than for the hypothetical 12mp A7SIII. But if you downsample the 42mp A7RIII image to 12mp, noise and motion blur per pixel will be very similar to the A7SIII (the noise in the A7RIII image will be much reduced due to averaging the noise over several pixels), with the potential to get a crisp 42mp shot. Upsampling a 12mp images to 42mp doesn't ever get you a crisp image. If your workflow allows for it I therefore don't see a disadvantage in shooting a high mp image as base material. You can always downsample it to get less noise and motion blur on pixel level.

[Deeliciouz]

Well! This is relevant information! It will now help for making a sensible choice. Thank you so much! 

[wonderotter]

This is more of a DSLR vs. mirrorless reply.

I own both a Sony A7R3 and a Nikon D850, 85mm 1.8 lenses for both (among others), 24-105 for the Sony and 70-200 f4 for the Nikon. I really like my Sony, but for fast-paced studio work I will always choose my Nikon. Why? Continuous auto focus is more accurate on my D850. I never worry about sorting through photos to find the sharp eyes with my Nikon...the Sony almost always nails focus, but I get a lower hit rate with my Sony. Also the rear screen on the Nikon is soooo much better than the anemic screen on the Sony. Dynamic range and colour on the Nikon screen are much better and really help 'wow' clients when we review shots during a session. Sony screen is too flat and too red...it just doesn't look good next to the Nikon. Another issue is environmental portraits. If you're using flash in a strongly backlit situation, the Sony really struggles to show a good view of what the subject s doing and it really struggles with autofocus. Even if you have Setting Effect turned to off, with strong backlight the camera will compensate for the bright light and leave your subject almost impossible to see. You can switch to spot metering...that helps somewhat, but still not perfect. Also I find the fact the Nikon image review is separate from the viewfinder a great advantage. On the Sony you either have image review on or off. Setting it to on really kills the flow and having it set to off makes reviewing a just shot picture a matter of interrupting shooting to hit playback. One last thing...I've had a couple of times when the A7R3 locks up while trying to clear the buffer. It actually happened last night...the camera froze while buffering 17 photos...I had to turn the camera off and wait a minute and then pray that the database isn't corrupted. That's with latest firmware and Sony SD cards. Try having that happen during a fast-paced high-paying session...no thank you. I like my Sony but for intense studio/location work, I just can't trust it over my Nikon. I own 3 Sony cameras so don't take me as a hater...but I do work professionally and I know which tool to use for the job : )

As far as pixel density being a challenge to tack-sharp focus, I haven't noticed much difference between my older 24mp cameras and my higher resolution ones. I shoot the same shutter speeds in studio (with strobes) as I always have (usually 1/125-160 - that's on a tripod) and on location, I use 1/250 and up, depending on focal length, subject movement, hand-held, tripod, etc..

Always happy to have my opinions challenged...that's how you learn : )