Low light sidekick for PWW-X70

[Peter Lowe]

I have found the X70 to be an excellent camera in a small package though dogged by a fixed lens that cannot open as wide as I would like for shooting in low light. My plan is to try and trade my way to a PMW 200 but these things take time and it is much easier to buy used gear than trade or sell. So I am looking into buying a small Sony mirrorless or Canon camera that I can use with a 24mm Canon f1.4 L lens to shoot in very low light too dark for the X70 to manage without applying very high gain, as it seems like gain above about +9 on the x70 is noisier than I am comfortable with.

Of course the best solution for this would probably be the Sony a7s but it looks like it will cost a bit more than I want to spend at the moment. So what would the next best Sony e-mount (Canon? Panasonic?) body be?

I have found an A6000 for a good price. My question is do you reckon the A6000 with upgrade to XAVC-S with a good F1.4 lens will most likely deliver better image quality with less noise in very low light than the pxw-x70 or not? I am well aware the A6000 does not have off camera audio capability and other limitations but my big concern is image quality in low light. Maybe the PMW 200 being an older model would not do as well as the x70 in low light anyway despite its superior lens?

Any advice or suggestions on this would be most welcome as I do not have the opportunity to do tests and need to make a decision quite soon.

[David Barnett]

Sony VG900 w/ Sigma 35mm 1.4 is great in low light. The colors are a bit of a challenge to matchup, as the x70 seems a blueish-green hue whereas the VG900 a orange-ish red.

The Sigma's def the lens to look for if 35 does what you want. I use it for the wedding dance floor shots.

[Peter Lowe]

Thanks David, with so many different models in circulation it is good to hear which one is good for what and apart from all the hoohah about the A7s low light performance does not often get as much attention in reviews as other features do.

If you have an X70 as well as a VG900 in what circumstances do you prefer to shoot with the X70 - or is it just that you need two cameras to shoot at the same time for some of the work you do?

[Peter Lowe]

Another option I have is to team up an A7ii body that I use for stills but delivers crappy video - together with an atomos or some other external recorder - though if the a7ii's video "challenges" with moire, aliasing etc are caused by the sensor maybe hooking it up to an external 4K recorder will merely amplify the problem rather than delivering a cleaner file?

The a6000 seems to get much better reviews for video performance than the a7ii but it has a smaller sensor so may not do as well in low light as the a7ii?

[Paul Anderegg]

My X70 f4 1/30 shutter at 33db, matches the luminance level of my A7sII f4.0 1/30 shutter at 3200 iso. :-|

The A6500 is like a mini A7RII...I saw a comparo yesterday where they put the same lens on them and side by side all the way to maximum 25600 iso, there was no picture difference in crop mode.

Paul

[Nick Fotis]

Not too surprising, pixel density (or size, if you prefer) is similar between the α6500 and the α7R ii.

If you want a low light video camera, you should check for lower resolution, with big fat pixels like the α7S variants.

N.F.

[Jeff Pulera]

As Paul alluded to, remember that you can drop shutter to 1/30 to get extra light when you need it, really helps!

Thanks

Jeff

[Peter Lowe]

Yep big pixels make a big difference though I suspect a lot of other tricks are also involved otherwise you'd expect the old Canon 5d to perform same in low light as the A7s since both are 12mp full frame cameras.

What I would like to know is if the a6000 line benefits from lessons learned by Sony from the A7 line or just uses the same tricks - though the only way to tell I guess apart from industrial espionage is from side by side comparison of different cameras at same settings, as Paul seems to have done.

This encourages me to also have a go at a similar experiment though not as expert as Paul's to compare the performance in low light of my x70 and a7ii though I don't have access to an a6000 or an external recorder to see how their output would compare

[Peter Lowe]

Originally Posted by Paul Anderegg

My X70 f4 1/30 shutter at 33db, matches the luminance level of my A7sII f4.0 1/30 shutter at 3200 iso. :-|

The A6500 is like a mini A7RII...I saw a comparo yesterday where they put the same lens on them and side by side all the way to maximum 25600 iso, there was no picture difference in crop mode.

Paul

Hmmm... that's very interesting since if I remember right I also came across a (not so positive) review in another forum pointing to a family resemblance of the a6000 and the a7 - so maybe a lot has changed since then in both lines? I will try to find that old post again

[Nick Fotis]

Originally Posted by Peter Lowe

Yep big pixels make a big difference though I suspect a lot of other tricks are also involved otherwise you'd expect the old Canon 5d to perform same in low light as the A7s since both are 12mp full frame cameras.

A decade separates these cameras (the original Canon 5D doesn't even have video capability). The pixel size comparison should be done between similar technologies.
The α7S series is 8 megapixels, I think.

N.F.

[David Barnett]

Originally Posted by Peter Lowe

If you have an X70 as well as a VG900 in what circumstances do you prefer to shoot with the X70 - or is it just that you need two cameras to shoot at the same time for some of the work you do?

I mostly shoot weddings. I try not to interchange them within a setting, so it varies. I look at it like the X70 is my goto, run & gun camera, whereas the VG900 is the art house lens cam. If it's a long day, 10 hours, with 2 hours of bridal prep, I'll use the VG900, but if the entire day is condensed with very little prep & quick photo session I'll go with the X70. Typically I use the X70 for photo sessions for its ND filters for outdoor use, and some photogs can be difficult to work with in regards to time. It's always the main aisle cam for the ceremony, as well as 1st dance, toasts etc. The VG900 for reaction shots, and dance floor reception footage because I can usually get away without additional lighting. Makes for better footage imho and the guests seem more natural.

Other events like sports, business events, public speaking etc I'd go with the X70. Keep in mind it has XLR inputs whereas the VG900 needs an adaptor for it, which I never got (about $600 I think). Myb if it was promo type work I'd use the VG900.

[Peter Lowe]

Originally Posted by David Barnett

I look at it like the X70 is my goto, run & gun camera, whereas the VG900 is the art house lens cam.

This is a great summary of why it makes sense (if not cents) to run 2 different cameras at the same time for different purposes instead of trying to find one camera that is perfect for everything.

So far looking into the different DSLR options that could be used as a sidekick for the X70 my only clear conclusion is whatever I choose or however much I spend it is likely to be more complicated than the X70 not only in terms of ergonomics like ease of use but also in evaluating other specs such as how much of the sensor is cropped in different video shooting modes.

I was starting to think that rather than try to save money by paying much less for a used a6000 the best sidekick option may be the newer a6500, particularly if it is as good as the A7RII in low light - but when I look at the reviews of the A6500 video capabilities I find little to suggest it delivers video quality that is significantly better than the a6000 and in some cases perhaps worse, as this comment from the Dpreview review of the a6500 suggests: "....1080 video is surprisingly poor by current standards, even taking a step backward from the original a6000..."

Am I right to suspect that one pays a lot more for the A7RII mainly for its stills capability rather than its video performance, the most significant new features of the a6500 compared to earlier a6000 and a6300 apart from 4K are image stabilization, audio inputs and more MPs for stills, and no matter how you peel the onion the A7S that sells used for a similar price as the new a6500 is still king of the hill when it comes to low light video?

Meanwhile for those who are interested just found this useful tool also on dpreview that enables downloading and side by side comparison of video stills of a test chart for many different camera models: https://www.dpreview.com/reviews/sony-alpha-a6000/8 (hope not a problem to post this link here even though it is from a different website as it is relevant to the discussion)

[Peter Lowe]

Today I tried to compare potatoes with ice-cream by doing my own kitchen-sink-style experiment to cross check low light video performance of the Sony PXW-X70 and A7II, since these are the two cameras I have in hand, trying to figure out what I consider to be minimal acceptable noise levels in low light.

My quick and dirty methodology was to shoot short clips of the same scene in low light with both cameras at same f-stop, focal length and shutter speed and use histogram info. to match up exposure - yep quite rough but close enough for what I wanted to do.

The A7II set at 1/30 f4 at 8000-12000ASA had as far as I could see roughly the same exposure as the X70 1/30 f4 at gain+30. Not surprisingly the footage from both beasts at this level was too noisy to be usable.

It was only when I reduced the ASA of the A7II about two stops to 2000ASA by opening up the lens to f1.8 that the noise level started to look acceptable on the 22 inch monitor that I use for editing.

So what I have learned is if I want to shoot in lower light than 1/30 with the X70´s kit lens wide open at f2.4-f4 and +9 gain (my benchmark for max acceptable gain), then I need to do so with a different camera - and by using the A7II with my best lenses wide open at f1.8-f2.4 I can probably squeeze out roughly an extra f-stop of usable light (ie double) before I hit what looks to me like the A7II´s 2000ASA ceiling for maximum acceptable noise in low light ie the only really noticeable difference between the two in terms of what they can do in low light is mostly due to the extra f-stop of the f1.8 lens I have on the A7II.

What I don´t know is how much better any other camera would perform in this situation - though from what I have read I would hope the A7S would do much better and the A6000/6300/6500 would also handle noise in low light better than the A7II, as perhaps the old Sony EX1 with its f1.9 lens would also do.

[Nick Fotis]

In general, higher resolution sensors are worse for high sensitivity video applications. For 4K video, 8 megapixels are enough.

A modern 8 megapixel Super35 sensor like the Canon C300 can pump much more light per pixel than the similarly sized APS sensors of 24+ megapixels.

If you want higher sensitivity, do not go with full frame cameras like the Sony α7R at 40+ megapixels, but go for lower resolutions like the α7 ii or the α7S ii.

N.F.

[Peter Lowe]

Thanks Nick for sharing your thoughts on this. Do you reckon an a6000 would deliver better video than the A7II that is the choice I am looking at right now, as I already have an A7II and have found an a6000 for sale in my area. My guess is if we apply your argument about higher pixel density equals lower quality video in low light then the 24mp apsc a6000 would not be any better than the full frame a7II.