FX6 - ND on or off to open up all the way

A

Afterglow

Active member
Shooting interviews yesterday with 28-135mm lens on FX6 at 800 iso and wanted to open up all the way to F4 to de-focus background and use ND to get there but the minimum ND setting is a couple of stops and image was then way under.

Llighting was natural soft daylight through window with flat panel key light and a focused redhead backlight so there wasn't complete control over lighting. Also couldn't move camera or subject further apart because of limited space. Perhaps a slight increase in shutter speed (not ideal)? Or get a separate lighter ND?
 
Did you remove the ND out of the optical path so there was no ND in play? The CLEAR position in other words.

As you say there is a two-stop loss with electronic ND engaged at its lightest position. Disengaging the ND to CLEAR will obviously pick up those two stops lost to the ND's lightest setting. Using an external 1 stop, ND2 filter will get you halfway between the CLEAR and the two stop loss of the variable ND at its minimum setting. Most variable external NDs, Polar Pro and Freewell start at that minimum two-stop position (2-5) so no advantage in using them. Are you shooting 25 or 50p? If I'm shooting 50p on an interview and want to drop light without an ND I have at times gone to 100th of second and usually with no detriment to the image. I say usually because I tried it outdoors on an interview where it was a bit windy and the female presenter's long hair had a slightly unnatural movement to it as it blew around due to the higher shutter speed. No one noticed or said anything about it but I could definitely see the slight higher shutter strobe effect.

It's either that or a faster lens with ND I guess?

Chris Young
 
That f/4 Sony lens is an not a good choice for an interview. Its an industrial lens with no character and the f/4 max f-stop isn't going to provide nice shallow DoF bokeh. As has been said by others, the best solution is to use a better, faster lens that not only will allow more light control but also produce a more pleasing image overall. The Sony 85mm f/1.8 is a nice inexpensive lens for such purposes. An added advantage of using a Sony lens is that the face/eye detect is fantastic so you can just set it and forget about focusing if the subject moves around a little. So much easier today to shoot really shallow . . . if you want the look. If not, dial down the aperture. It gives yo options that slower lenses don't give you.

However, in this case, where you don't have a faster lens in your bag, you could have opened the lens nearly to full aperture, switched over to the high sensitivity mode and then dialed in enough variable ND to get the right exposure. The HIGH mode is slightly noisier than the LOW mode, but still better than most other cameras in the FX6's class and perfectly acceptable for most purposes. I try to stay in LOW as much as possible but don't give it a second thought when HIGH becomes necessary. I just hit an assign button to jump back and forth.

If you were not shooting LOG, then there are other alternatives available as well.
 
To echo Doug's comment, I will pretty regularly shoot in HI mode with ND activated both to allow me to shoot wide open and for the ability to fine tune exposure with the variable ND.
 
Thanks. Agree w all above.

Yes, shifting to high iso and dialing back stops with ND is one approach w trade-off being some extra noise - have done this before but wondered if there was another solution. (BTW def not shooting cinetone)

Yes, 28-135mm lens is industrial and doesn’t have much aesthetic appeal but a lot of the time its functionality and zoom range win out (understand that this series of interviews has no overlay so changing frame sizes between questions is the go). Perhaps time to consider another zoom for interviews w approx 40-100mm range. Suggestions welcome.

And yes, shutter speed shift up is a possibility though some of these speakers are very animated.

Otherwise, it becomes a feature request for Sony, a light first stage ND.
 
If you switch to high-ISO mode, and dial the camera down to 3200 EI, noise is really a non-issue, and the two stops of sensitivity compensates for the two stops of minimum ND - so you have the same exposure as 800 EI (without the ND in place), but now with the ability to dial in however much ND you do need.
 
Grug said:
If you switch to high-ISO mode, and dial the camera down to 3200 EI, noise is really a non-issue, and the two stops of sensitivity compensates for the two stops of minimum ND - so you have the same exposure as 800 EI (without the ND in place), but now with the ability to dial in however much ND you do need.
Click to expand...

That is just smoke and mirrors. When you switch to the HIGH mode the camera is going to record at 12,800 ISO no matter what you do. Changing the EI just changes the look of the MLUT (if you choose to use an MLUT), which in turn may affect how you judge exposure on the LCD or an external monitor, but changing the EI will have absolutely zero impact on what is recorded. If your goal is to overexpose a little, then just overexpose a little. You don't need to mess with the EI for that.

In the CINE EI mode the camera is either going to record at ISO 800 or ISO 12,800. That's it, there is no in-between.You probably know this already, but I think it needs to be said for the benefit of others less versed with the camera who might be led to believe that EI actually changes something about the recorded video. It doesn't.
 
Sometimes smoke and mirrors are OK though - I'm not sure how the FX6 works but on the FX9 I do exactly what Grug suggested , drop the EI a third t5 a full stop. Doug is right in that it doesn't really change the ISO but if you are using the LUT to judge you're exposure as many of us do than it solves the noise problem. by overexposing, If you don't use an MLUT for exposure or to look at your image than its irrelevant as Doug suggests,. As I recall Doug doesn't like to use LUTs.
I think there might be confusion between Doug and Grug's EI or ISO numbers. Sounds like Grug is talking FX9 where High is 4000 ISO not 12,500. I don't know about the FX6. The A7siii will go to 12,500 and in that case lowering the ISO doesn't work as its ISO not EI. In fact if you lower the ISO then you'll revert to the LOW mode and a very pushed noisy image. So you simply have to get used to looking at an overexposed image. Of course you can output the Slog to a 1+ LUT in a monitor.
Now if you're not using Slog then on an FX9 at least , it does make sense to go to a High mode then drop the ISO a bit as Grug suggested , but don't go more than a 1/3 of a stop or so because you are really overexposing .
Personally I carry an N3 filter with me for this purpose - that's the best solution. Of course I also never use the 28-135 for interviews. These days I've gone to Sigma 1.4 primes because with AF I can shoot wide open with no focus worries.
 
scotchtape said:
I just bought an SLR magic 1-stop fixed ND to deal with the same "issue".
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In fact, I lie... or misrepresented the Freewell 2 filter set. I use the 95mm twin set on both the Sony 18-110mm and the 28-135mm if using these lenses on an A7. The 2-5 filter actually starts its rotation well before the 2 stop mark. To check this out I just ran it on a camera with the camera set to auto iris and when the variable ND was rotated 2/3rds of the way from its end stop position towards the 2 stop position it effected a 1 stop change in the auto-iris in the viewfinder.

In defence of the 28-135mm despite its lack of character. For me, it has proven to be a much more versatile FF lens than Sony's own 24-105mm photo lens for video. Better manual focus, electronic "parfocalness", and an iris ring. Under critical observation, it seems to offer no better or worse IQ and character than Sony's much-lauded 24-105mm which I ditched in favour of the 28-135 for video work.

For working under demanding atmospheric situations I find the 18-110 and the 28-135 Sony zooms with the Freewell NDs very useful tools for the A7 mirrorless video shooter. Different from your FX6 as it has NDs. One case that really comes to mind is when I had a shoot in a timber mill where the air was full of fine floating sawdust from the band saws. This sawdust was moist with sticky sap! When this sawdust settled on anything it just stuck to it like s**t to a blanket. Like all over the camera body in my case. I definitely did not want this sawdust to find its way to the A7's sensor filter during a lens change. That's where the Freewell NDs proved their worth. It took a soft cloth with Eucalyptus oil to dissolve the stickiness to enable the removal of these little Klingons from the camera kit and the NDs used that day.

As Doug stated a decent value lens is that Sony FE 85 f/1.8 which will give you a much nicer interview look.

Chris Young

 
The biggest issue w the 28-135 lens is not just characterless look but it’s really not that sharp. (Have experimented with turning stabilization off when on tripod to improve sharps. Anyone else tested this?)

Matching other lenses at same focal length like Sony 16-35 GM 2.8, you don’t have to pixel peep too close to see why former doesn’t cost heaps. Anyway, that’s been discussed ad nauseum; fact is it’s still a v handy lens w great zoom range for fast shooting. Its AF also seems okay from the rare couple of times it’s been used.

As for ‘gain’ switches, they’re kind of decorative in slog although on this camera position 1 is set to match the installed LUT’s exposure to the non-LUT optimal white level and that’s working okay.

Thanks for tips about ND screw-on filters.
 
I am confused by this word "Character." Is there a similar lens that's an F4 that does have character or is it just that its f4? Is it because its not sharp (I agree about that - the 18-110 is sharper) or is there something more mysterious missing? Not enough aberrations ?
 
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I find zoom lenses more useful than primes because interior interviews space is small and options to put the camera, subject and lights, especially for 2 camera shoots is limited. 24-70 2.8 would be my choice but I think f4 on a FF is a pretty shallow dof.
 
I have always found the 70-200 f2.8 to be a perfect lens for interviews though I guess it depends how wide you typically want them. I rarely need to go to 50 or wider unless its a very small room and then a 50mm prime or a 24-70 works. 100mm is a little short for my taste. For 1 lens a 50-150 might be perfect . I usually carry a 70-200 and 24-70 f2.8 as a matter of course. For primes I'm carrying a 50, 85 and 105 all sigma f1.4 AF for that low low low DOF most clients seem to want. I'm loving the 105 if i have a big enough space.
 
alaskacameradude said:
I would recommend the Tamron 35-150 F2-2.8
native E-mount lens if you are looking for
something in that range….if you have the budget.
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I'm seriously considering one of those. F/2.0 to F/2.8 sounds interesting with that range. I got the new APSC 18-300mm for the FS7 for when I need reach, 16.6 x, and have been more than satisfied with it for the price and image quality.

Chris Young
 
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