DV Info Net

DV Info Net (https://www.dvinfo.net/forum/)
-   Sony XDCAM PMW-F3 CineAlta (https://www.dvinfo.net/forum/sony-xdcam-pmw-f3-cinealta/)
-   -   F3 sensitivity against EX1 (https://www.dvinfo.net/forum/sony-xdcam-pmw-f3-cinealta/498550-f3-sensitivity-against-ex1.html)

Michael Power July 18th, 2011 07:40 AM

F3 sensitivity against EX1
Looking at a range of still lens for my F3 and wondering if its increased sensitivity over my EX1 is measurable in the number of stops? I've been shooting a whole bunch of talks in halls using existing lighting where my EX1 is set around F2. If I use the F3 with a lens with max aperture of F4.5 will I have enough light? Will I go far into gain? Thx

Chris Medico July 18th, 2011 09:11 AM

Re: F3 sensitivity against EX1
The F3 is a lot more sensitive than the EX1. You can run a lot more gain on the F3 and get a completely usable picture where I've found with my EX1 that +3 is the limit before there is too much noise. The F3 at +18 looks cleaner than the EX1 at +3. Also the noise you get on the F3 is not as objectionable as the noise on the EX1. I don't have actual numbers but its got to be in the area of 3 stops faster when you take into account the usable gain range of the F3 in comparison to the EX1.

I've been planning to make a demo reel to show clients the advantages of stepping up to the F3 on their shoots. Showing light sensitivity advantages of the F3 over the EX1 is one of the comparisons that will be included. It won't be a scientific test but real world examples.

Thierry Humeau July 19th, 2011 08:32 AM

Re: F3 sensitivity against EX1

The F3 is indeed more sensitive but using F4.5 lenses, you will end up defeating one of the main aspect of large sensor cameras which is to obtain a shallow depth of field and soften the background.



Dave Sperling July 19th, 2011 02:14 PM

Re: F3 sensitivity against EX1
A bunch of different variables involved...
Though I've found the F3 a little faster than the EX1, I think that's particularly true at 1080i.
With the settings I've been using to more or less match my F3 and EX1 when shooting on a recent project (1080p30 / Cine 3 gamma) I've found I get about the same exposure level from the EX1 wide open that I get on the F3 from a Nikon 80-200 / 2.8 wide open. Both set at 0db gain. Admittedly the Nikon probably loses some light internally (the 2.8 is an f/stop, not a t/spop) so I'm guessing the F3 is just over a stop faster than the EX1.
That doesn't get you to a 4.5 as a comparison stop, so I'm thinking you'll be aroud +6 or +9 db on the F3 for matching exposure level. However, the F3 still looks great at those increased db levels.
But I would still recommend getting a faster lens if you can...
NOTE: The findings above were completely unscientific, they just happened to be the exposures I picked in working to get matching shots on the two cameras with my picture profile settings in place.

Alister Chapman July 19th, 2011 02:25 PM

Re: F3 sensitivity against EX1
At 1080i the F3 is 800asa, the EX1 approx 360asa, so about one stop between them. But it's the noise that makes the difference, or in the F3's case the lack of it.

This means you can use +6db and gain another stop or even +12db gaining 2 stops and making the F3 3200asa yet still have a useable image. At +6db it's still cleaner than the EX1.

Michael Power July 19th, 2011 07:03 PM

Re: F3 sensitivity against EX1
Thanks for info. That's about what I was expecting and hoping for, one stop extra at 0db, then two stops more with negligible gain.

Thierry, I have some primes and a couple of shorter zooms which are all about 2.8 which are fine for stop-start shooting, but there are situations when stopping for a lens change is unfeasible and a short DOV is not the best approach. Pragmatically, I need a zoom lens that will emulate the EX1's lens for talks and fast doco shooting.

Any suggestions in the Nikon-mount stills domain?

Thierry Humeau July 19th, 2011 09:01 PM

Re: F3 sensitivity against EX1

In my quest for great Nikon mount zoom lenses for the F3, I came to realize that the best candidates as far as price/performance, are actually not from Nikon. Here are a few suggestions:

- Sigma 18-50 F2.8. It has been discountinued and replaced with the 17-50 F2.8. I like the older model because it does not have IS (Image Stabilization) which the MTF mount cannot utilize anyway and because of this, the lens is lighter, simpler and minimal focusing distance is better than the the new 17-50. Also, the focus ring has a bit better range, not great though.

- Sigma 50-150 F2.8. This is a fantastic range for interviews if you need to vary betweeen two frame sizes. That lens has also been discountinued by Sigma but can be found on eBay at around $650. It is pretty much the equivalent of a 70-200 on a full frame SLR. This is quite a unique offering from Sigma as there are no similar offering from other manufacturers with a fast F2.8 constant aperture. Rumors are that they Sigma is about to re-issue a version of this lens with IS.

- Tokina 11-16 F2.8, a great super wide zoom. I am not too crazy about the sliding focus ring to switch between AF and Manual but the built and optical quality are excellent.

The MTF Nikon adaptor is working fine with those lenses but it would be nice to see an adaptor with a larger and smoother aperture control and a way to power the internal IS feature now offered by many of those lenses from the F3 mount.

Any other lenses recommendations are welcomed.



Alister Chapman July 20th, 2011 01:53 AM

Re: F3 sensitivity against EX1
For a cheap and cheerful lens, I use the Nikon 18-135mm. It's f3.5 to f5.6, but doesn't really stop down until you go beyond 100mm. The zoom range is very useful and I used this lens a lot at the weekend shooting and airshow. It really is not the best of lenses, telescoping a lot, no calibrated focus scale and not fast. But for run and gun, not having to swap lenses is a boon. It's also surprisingly sharp even wide open and at f4 you still get nice DoF.

Best bit is it's so cheap you can afford to have one just for occasional use. I paid 150 used for mine. Of course once I get my 2/3" B4 adapter into production all these issues go away :-)

Ned Soltz July 20th, 2011 08:45 AM

Re: F3 sensitivity against EX1
While the thread has already gone somewhat OT, question about those Sigma lenses-- Are they internal focus/non-telescoping for mattebox purposes and are they parfocal?

These are of course the basis for the Red 17-50 (18-50) and 50-150 rehoused glass.

Ned Soltz

Thierry Humeau July 20th, 2011 10:05 AM

Re: F3 sensitivity against EX1

I am away from the office now but all these lenses are internal focus, I think the 17-50 (18-50) expands but neither the 50-150 nor the Tokina 11-16 do.


Alister Chapman July 20th, 2011 02:26 PM

Re: F3 sensitivity against EX1
The telescoping issue is why I keep coming back to my old Tokina AT-X Pro 28-70mm f2.6 Mk1 lenses. These do not telescope and are of all metal construction with manual focus scale and iris scale. Optically these are good lenses provided you close down by a half stop, so really the useable max aperture is f3.5, but they are constant aperture throughout the range and focus shift is minimal as you zoom.

I wish I could find a non telescoping 20-80mm (or thereabouts) f2.8 zoom that's sharp at f2.8 and constant aperture, manual iris ring, good fixed focus scale.

Warren Kawamoto July 20th, 2011 02:59 PM

Re: F3 sensitivity against EX1
Off topic, but does anyone know how visual noise levels compare between the F3 and FS100? I would assume the F3 is much better?

Alister Chapman July 21st, 2011 12:53 AM

Re: F3 sensitivity against EX1
To be honest there isn't much difference. Noise levels and visibility are similar.

Timur Civan July 22nd, 2011 02:28 AM

Re: F3 sensitivity against EX1
From what i understand, the FS is really only different image quality wise with regards to dynamic range, and even then, its a half stop difference.

I've heard the F3 handles the image slightly better overall. i chalk that up to a more expensive signal processor, or even just a somewhat better implementation.

The FS100 is alot of camera for the money. If you dont need, SDI, and all the gadgetry necessary for high end production, its good for 90% of all shoots. infact, i have a shoot tommorow wherei wish i had a FS in stead of the F3. I just need a smaller camera, but not a DSLR.

Alister Chapman July 22nd, 2011 03:26 AM

Re: F3 sensitivity against EX1
There is a full stop difference in dynamic range between the FS100 and F3. In addition the processing isn't as sophisticated and the FS100 has slightly lower horizontal resolution. Detail correction and aperture correction are not done so well on the FS100 and the cinematone gammas are not as nice as the F3's cinegammas. Overall the FS100 lacks the verisimilitude that the F3 has. The bigger annoyance is the course steps and limited adjustment range in the picture profile settings. While you can change most things often the range is just +/- 7 steps.

I don't want to sound too negative about the FS100 as it is a great little camera and not that far from an F3, but the F3's images, for me at least have a nicer look.

All times are GMT -6. The time now is 12:52 PM.

DV Info Net -- Real Names, Real People, Real Info!
1998-2020 The Digital Video Information Network