slashcam review

[Noa Put]

Slashcam has done a review on the camera:
Test : Sony NEX-EA50 NXCAM: Einleitung


I saw this video but I think it gives a wrong impression at 30db gain, if I would not know better I"d say that 30db was perfectly usable but I know it isn't, what do you guys think? I posted a comment on youtube about this but it appears Slashcam doesn't want any opinions as they ereased my comment immediately :)

Sony NEX-EA50 Div ISOs HD 1080p - YouTube

[Chris Quevedo]

So where would you say then is the highest gain you would feel comfortable shooting with?

[Noa Put]

Not sure about the gain equivalent but 1600 iso is as high as I go, 30db would equal 5000 iso.

[Chris Harding]

Hi Chris

Noa is very particular about his shots but for general work 24db is pretty clean and quite usuable too. In ISO that's about 2500 ISO ... In a nutshell the camera has a base ISO of 160 so at 0db gain the ISO is 160 and it doubles every 6db of gain that you add ..so 6db gain = ISO 320, 12db gain = ISO 640, 18db gain is ISO 1280, 24db gain is ISO 2560 and 30db gain is ISO 5120

Using Noa's limits you will always get a perfectly clean, noise free image but for me sometimes I need to go a wee bit higher.

Chris

[Joel Corral]

For me, 24db is a lot of gain & I find that unacceptable for my work. I guess its a matter of taste. I will go as far as ISO 1600 but really only feel comfortable at ISO 1250 or below. And still ISO 1250 is pretty noisy.
I don't find the camera being clean at high gains as everyone raves. As I have stated before, that's my only grip really.

JC

[Noa Put]

And still ISO 1250 is pretty noisy.

That's why I found the 5000 iso sample from Slashcam not representative for what it really is, on that video it looks pretty clean to so I don't understand why they don't provide some raw framegrabs to compare (or even a download link to the raw file) instead of showing a heavily compressed youtube film.

[Ron Evans]

Noa, have you tried seeing if there is any difference in performance when the camera is in full auto compared with full manual ? I just wonder if Sony have some different noise reduction in place for auto operation !!!! Because I have seen similar sorts of comments about the CX700 yet I am happy with mine which is always in auto mode looking at data code with it at 21db. By contrast my NX5U which is always in full manual is a disaster at 12db and then I always have to clean up with Neat filter.

Ron Evans

[Noa Put]

I just wonder if Sony have some different noise reduction in place for auto operation !!!!

There is no hocus pocus going on behind the scenes :) What you see is what you get. I have been planning to do a more thorough comparison to show the noise but I can already say my cx730 is cleaner at higher gains and comparable exposure.

[James Manford]

I use no more than 24db / 2500iso to my eyes that is a clean image and more than enough in most situations.

I try to keep it much lower using lighting though.

[Chris Quevedo]

is the noise cut down some by using a recorder thru the hdmi port?
and as far as noise reduction, how does everyone handle that? i'm sure theres a limit to denoising software, but how far can you push the camera and use some sort of denoiser yet still get acceptable shots in your opinion?
it seems most people around here use neat video for noise, right? just trying to get a grasp of the limits and boundaries

[Chris Harding]

Hi Chris

I have the best de-noiser that money can buy!!! It's called lighting!! At receptions I use an on cam light and lock the gain at 18db and basically expose with the light. During speeches I have 4 x 55W CFL lamps on a high stand that bounce back into an umbrella and do much the same and it works a treat!!

Far better to light the work correctly during shooting than try to remove noise in post..besides I'm impatient and noise reduction plugins take forever to render!!

Chris

[Noa Put]

On my system an older version of neatvideo is painfully slow, results are excellent though but only usable on some short clips due to the time it takes. I"ve seen now that the new version supports gpu acceleration so that might speed up things a lot but have no experience in that. I otoh never use light at a wedding unless I really have to, that's why I use fast lenses, which is one of the main reasons why I bought a big sensor, exchangable lens camera, if you stay with the slow stocklens then you have no other choice then use extra lights at dark venues.

[Chris Quevedo]

Originally Posted by Chris Harding

Hi Chris

Noa is very particular about his shots but for general work 24db is pretty clean and quite usuable too. In ISO that's about 2500 ISO ... In a nutshell the camera has a base ISO of 160 so at 0db gain the ISO is 160 and it doubles every 6db of gain that you add ..so 6db gain = ISO 320, 12db gain = ISO 640, 18db gain is ISO 1280, 24db gain is ISO 2560 and 30db gain is ISO 5120

Using Noa's limits you will always get a perfectly clean, noise free image but for me sometimes I need to go a wee bit higher.

Chris

its interesting that you say that because the Canon 7D's base ISO is supposed to be 160 as well if Philip Bloom is to be believed. but how does someone determine that sort of thing? is it just from trial and error that we arrive at that?

[Chris Harding]

Hi Chris

I would assume that the base iso is a spec from the manufacturer ..I have no idea if it's a technical spec based on the sensor size or if it's physically measured with a specific lens (or the supplied lens) At a wild guess I would think with something like a DSLR it would be the amount of light that the sensor can capture in a given situation in a lab (I could be horribily wrong (and more than likely am)) but I cannot see a camera base iso rating involve a lens as a lot more light passes thru an F1.4 iris than a F4 iris

Does anyone know how a camera's base iso rating is determined??

Chris