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For those in love with the FULL FRAME look which system gets closest in 4K?


Andrew Reid

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7 hours ago, Jn- said:

Well, that seems a steal! great value, is it new?

I've included below the methods that can be used for calculating crop factor/focal length multiplier.  Although it's pertaining to the Canon 5D MK. IV maybe it can be of use to you to figure out whether the supplied values for the G7 are correct.

Crop factor (CF) for 5D mk. 4.

[...]

Crop Factor is the ratio of diagonals for the optical image circles. Width ratio and/or area ratios are meaningless as they don't relate to the actual optical imaging circles, especially when using the correct Crop Factor for matching cameras and lenses for specific shots and DOF via Equivalence math

Right now an A7S II or A7R II (much better AF) along with a Canon 5D III could work really well. Use the 5D III to shoot raw stills of the scenes. Then in post color match the stills to the A7x II footage. I've done this by eye and it's not that hard: with the 1DX II and C300 II to the A7S II:

Note that no one could tell which camera was which for sure until I gave the answers. It might also be possible to create a 3D LUT for A7x II to Canon, however shooting reference raw stills will probably work better.

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Yeah, but there's definitely a market for it.  More people have looked at dpreview A7RII studio charts than all the movies I've ever made.   Now, I'd like to say my movies have probably made more

The video crop factors of the current 4K cameras, and an easy way to calculate crop factors... Read the full article

I would wait and see what initial reviews say about rolling shutter, battery life, and overheating. All are big issues on the current Sony cams, and it remains to be seen if they've been improved at a

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On 27 August 2016 at 7:05 PM, Bill Sepaniak said:

I also large format fine art photography ... 24 X 36" or larger that I print (and sell) on canvas. A little harder to do with an A6300.

Obviously you get more pixels with the A7Rii, but would you argue that a speed boosted lens on ASP-C is noticeably lower quality at a given pixel count than the same lens on full frame? Just interested in your opinion, as I can probably only afford to get the A6300 with some sort of focal reducer anyway.

What is interesting for video is the flexiblity you now get with primes; my nikkor 50mm f1.2 lens can now function on the A6300 as (35mm equiv):

50mm f1.2 (boosted)
75mm f1.8 (unboosted)
100mm f2.4 (digital zoom)

... all at true 4K. Gone are the days when you needed six or seven primes to shoot video.

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20 hours ago, Jn- said:

Well, that seems a steal! great value, is it new?

Yes. I havent time to look into the maths but I know you get a bigger image with the G7 and better video quality, plus I got £345 out of the deal from selling the GH4 (less whatever the required spare battery costs). 

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1 hour ago, BasiliskFilm said:

Obviously you get more pixels with the A7Rii, but would you argue that a speed boosted lens on ASP-C is noticeably lower quality at a given pixel count than the same lens on full frame? Just interested in your opinion, as I can probably only afford to get the A6300 with some sort of focal reducer anyway.   ...

No. See this: http://www.newsshooter.com/2015/08/06/sony-a7rii-part-5-low-light-testing-against-the-a7s-fs7-and-gh4-and-impressive-results-using-the-metabones-speedbooster/

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Very nice article. I wish that if we were discussing  motion picture production we'd consider crop factors in terms of the 1.85 ratio cropped out of a vertical piece of 35mm film--ie., the "S35" crop that most people consider "full frame" when shooting movies. There are exceptions, of course, with VistaVision, and newer big sensors. Still, it seems more appropriate to me to look at, for instance, what lens you need to use on a GH4 versus what lens you'd use on an FS100 for the same shot. For many years I shot 16mm and then 2/3" chip broadcast cameras. A 25mm lens for me was reasonably close to "normal." When doing still photography with the old Nikon, a 50mm was "normal." And with the Hasselblad, the 80mm was "normal." When shooting with the FS100, I've found I use the 35mm old Nikkor as my "normal" lens, and use the same lens for the same situation on the GH4 with Speedbooster.

I don't recall anybody shooting video or film a few years ago ever comparing lens focal lengths to still camera lenses, until the DSLR revolution came along. It would be nice to revise our thinking and leave the "full frame" still camera out of the equation when talking about crop factors for movie production.

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2 hours ago, DBounce said:

 Seems most here are convinced that FF on the A7Rii is garbage. Yet I thought the difference in iq was marginal when compared to the aps-c mode. So much so that it was my preferred shooting mode 90% of the time. 

The studio charts on dpreview show how strong the aliasing/moire is using FF vs S35 on the A7RII. (They have also updated it with the XT-2):

https://***URL removed***/reviews/image-comparison/fullscreen?attr29_0=sony_a7sii&attr29_1=sony_a7rii&attr29_2=sony_a7rii&attr29_3=sony_a6300&attr72_0=4k&attr72_1=4k&attr72_2=4k-apsc&attr72_3=4k&normalization=full&widget=378&x=-0.003759398496240741&y=0.0110314396028683

https://***URL removed***/reviews/image-comparison/fullscreen?attr29_0=sony_a7sii&attr29_1=sony_a7rii&attr29_2=sony_a7rii&attr29_3=sony_a6300&attr72_0=4k&attr72_1=4k-apsc&attr72_2=4k&attr72_3=4k&normalization=full&widget=378&x=0.22088384225870783&y=-0.5714285714285713

 

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So, Andrew, how would you compare the image and color of the A7Sii with the 1dC?

The tilt screen and in camera 5 way stabilization are really tempting, but I have heard complaints the stabilization problematic. And I loathed battery life of the A7 I once owned. But if the image and stabilization are good the battery life would be bearable.

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39 minutes ago, DBounce said:

I guess the problem is I don't spend my time shooting studio charts.

Yeah, but there's definitely a market for it.  More people have looked at dpreview A7RII studio charts than all the movies I've ever made.  

Now, I'd like to say my movies have probably made more people cry than dpreview studio charts, but I suspect that's somehow wrong too.

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37 minutes ago, jacoblewis said:

I think your math might be a little off on the X-T2(?)

1.52x (APS-C) + 1.17x (additional crop in 4k) would = 1.69x crop factor, not 1.75x

 

The X-T2 sensor width is 23.6 mm and Full frame is 36 mm (1.525x crop factor). The additional crop factor is 1.17x for 4K (which is multiplied not added):

4K crop 36.0/23.6 *1.17 = 1.78x

The figure 1.75x is technically incorrect. The calculation people use is 1.5x1.17 = 1.75. This calculation has to be rounded to two significant figures (high school science) so would have to be expressed as ~1.8x. 

 

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On 27/8/2016 at 10:28 PM, Francesco Tasselli said:

Dear Andrew,

thank you very much for your post, that is very useful to clarify what the crop factor is, while in the web there is a big confusion.

However I’m a bit disappointed you didn’t mention NX1 in your article, whereas this superb camera is living a second life beyond the official “death” also thanks to the great passion of some members of your forum.

Best

Agreed. Nx1 is often 'forgotten' in such comparisons (I'm not talking of EOShd alone).

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On August 29, 2016 at 10:13 AM, DBounce said:

 Seems most here are convinced that FF on the A7Rii is garbage. Yet I thought the difference in iq was marginal when compared to the aps-c mode. So much so that it was my preferred shooting mode 90% of the time. 

Same here. The main advantage of FF is the small DoF, in which case aliasing artifacts are less and next to invisible. Also the A7rii FF mode has much less rolling shutter as well so that is another reason that is the preferred mode for handheld use. Then crop+clear zoom just gives you all the range that you need in one tiny package (in this case 35mm gives you 35-105):

camera2.jpg

 

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Yeah I find the A7R2 in FF mode to be pretty good in good light, and being able to get an extra 50% zoom whenever you need it by going to S35 is great.

Speaking of switching from FF to S35, I've been testing out the 24-70mm 2.8 GM with the A7R2 recently and it sure is awesome having a 24-105mm range at f/2.8 all in one lens.  And of course the image quality is great.  Almost makes up for the huge size and weight.

Here's a 4K screengrab at 24mm FF f/2.8.  Sorry for the exposure.. didn't have ND filters at this point.

24-70_00_edit.jpg

And at 70mm FF f/2.8:

24-70_02_edit.jpg

 

A few other thoughts on this lens for video, since it is full-frame and gives a pretty good full frame look IMO:

  • The size and weight make handheld shooting much more stable than my smaller/lighter e-mount lenses, especially when using the viewfinder for a third point of stability.
  • The physical AF/MF button is pretty handy if you like to use AF sometimes, but occasionally want to quickly switch to MF without giving up one of the other custom buttons
  • The programmable button on the side of the lens is also pretty useful. I think by default it's set to focus hold, which is good for using AF to lock focus on something, reframe on a different subject, release focus hold and get a smooth focus transition to the new subject.

 

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How about the 1.5x-crop a6300 with the 0.71x EF-to-E Metabones Ultra Speedbooster, giving 1.065x, basically full frame 4k with full-frame depth-of-field results on Canon glass? Plus the Speedbooster gives an extra stop of light and even increases effective lens resolution. But although the June firmware helped AF, but there are still AF issues with some lenses.

Looks like the a6300 (with its 6k-to-4k oversampling/full-sensor readout) delivers currently unbeatable resolution:

https://***URL removed***/reviews/image-comparison/fullscreen?attr29_0=sony_a7sii&attr29_1=canon_eos1dxii&attr29_2=sony_a7rii&attr29_3=sony_a6300&attr72_0=4k&attr72_1=c4k&attr72_2=4k&attr72_3=4k&normalization=full&widget=378&x=0.4307963787018565&y=-0.174296745725317

https://***URL removed***/reviews/image-comparison/fullscreen?attr29_0=sony_a7sii&attr29_1=canon_eos1dxii&attr29_2=sony_a7rii&attr29_3=sony_a6300&attr72_0=4k&attr72_1=c4k&attr72_2=4k&attr72_3=4k&normalization=full&widget=378&x=0.22088384225870783&y=-0.5714285714285713

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19 hours ago, lwestfall said:

I'm looking at the EF-to-E Speed Booster because I have Canon glass, and the A-mount lens line-up is not that inviting...

Maybe the 5-axis-stabilized non-overheating a6500 will materialize soon...

Sweet, it's official! So the answer for me to the question of high-quality full-frame 4k (that doesn't break the bank) is the a6500 with the EF Metabones Speed Booster.

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