Sigma Fp review and interview / Cinema DNG RAW

[BTM_Pix]

5 minutes ago, Andrew Reid said:

Sigma advertised the Fp with a lot of manual stuff, PL lenses, all sorts, so it's a bit strange they didn't see such an obvious thing in testing!

Its shocking to be honest, especially as it works in Cine mode.

As far as manual lenses go I'm predominantly going to be using M mounts on it with the Leica adapter for stills so I'm guessing I'll be OK with it until they fix it but still.

 

[BTM_Pix]

17 minutes ago, paulinventome said:

What i do notice though is in low exposures in stills mode the brightness flickers randomly. Does everyone see this? I have reported that as well

Its the same on the SD Quattro (even with native electronic lenses) once you get to -2.0 and below on the meter.

My suspicion is its also related to a conflict with the monitor brightness function where at that level of underexposure it would ordinarily increase the brightness so it is increasing it momentarily before its clamped back down by the "Preview Exposure in M Mode" being set to ON.

 

[Lars Steenhoff]

So there is this menu option :

color shading

its under lens optics compensation

Here you can set the aperture and focal length, but still the camera does not seem to take this information into consideration.

[Andrew Reid]

It does seem to be the Preview Exposure in M Mode where the bug is. On the card, and in playback mode, a still does match the video recording at same manual settings and ISO.

The preview in M mode function is too bright in live-view, giving misleading exposure as you set your settings.

I too tried the manual aperture and focal length input in the optics correction menu but no luck with a fix yet.

I am positively certain this is not going to be a long term bug and in a couple of weeks will be 100% fixed.

Very annoying in the here and now though.

Might be related to another bug... With manual lens and mystery aperture, Exposure bracketing doesn't work.

UPDATE: It does work, camera has to be in continuous shooting mode not single shot. Funnily enough the exposure in live-view now matches the +1 ev shot perfectly, so there's a work-around of sorts.

[buggz]

Question about stills flash.

ONLY 1/30 or less is available for flash speeds.

There isn't a mechanical shutter?

[Lars Steenhoff]

No mechanical shutter, thats correct.

[paulinventome]

Second attempt as i had uploaded the wrong images before.

So long short short,  i was testing resolution of 6k vs FF UHD to check the level of aliasing. The only chart i had was an old one i'd printed off myself many moons ago but should be enough to create issues (but i really need to find a better way...)

But i can clearly see 6K still vs scaled UHD but what i found interesting is if you switch to DC mode i am pretty sure you're just getting a 1:1 crop of the sensor in UHD - it looks similar to the 6K. Either way the DC UHD RAW mode is much clearer than the FF.

But i need to do some better tests but try it yourself and see what you think.

cheers
Paul

 

So top is full frame UHD and lower is DC UHD, see how much clearer the lines are

 

[Lars Steenhoff]

I think for lower iso the dc crop mode may give the best results based on your test.

The crop mode is also more noisy, so for higher iso the full frame mode will give cleaner results

[paulinventome]

6 minutes ago, Lars Steenhoff said:

I think for lower iso the dc crop mode may give the best results based on your test.

The crop mode is also more noisy, so for higher iso the full frame mode will give cleaner results

I've just found photoshop on my laptop so used that and yes, the UHD DC crop is a pixel for pixel crop from the centre of the sensor. You can A/B stills and cine and it's identical. So in this mode with no OLPF it would be interesting to see how much moire there is in motion.

I could guess that perhaps the DC HD mode would be pretty good too. The full frame HD mode not so much but there's a even scaling for HD.

cheers
Paul

[Lars Steenhoff]

 

 

[Lars Steenhoff]

 

[Lars Steenhoff]

 

 

[Lars Steenhoff]

 

[Lars Steenhoff]

 

 

[Chris Whitten]

Sigma are a weird company. Their lenses are so sorted, but they keep releasing cameras that aren't finished or have obvious flaws.

In the past I owned the DP2 and DP3 Merrills. Superb images, but only at ISO100-200 and no way to process the raw without their cluncky 'Pro Photo' software.

Based on a few forums such as this, I dove in again and bought an FP.

Haven't tried the video yet, I'm a BMPCC4K owner. Maybe I can use the FP on a gimbal? I'm certainly used to CinemaDNG and Resolve (former BMPCC owner).

In stills mode I'm using the FP with Leica M glass - I would love some Contax/Zeiss too.

At the moment I have the camera set to full manual with auto ISO, because you can't have exposure compensation without auto ISO (why?).

At -3, my raw images are still blown out in the highlights, although recoverable in Capture One. I guess I'm going to -7 next. Just seems bizarre in this age where there are so many fantastic cameras, to have to fiddle about to get a properly exposed raw image.

[Lars Steenhoff]

There is a bug with exposure in stills mode when using lenses that don't communicate with the camera.

I hope this will be fixed in the next firmware

And for sure you can use the camera on a gimbal

[Chris Whitten]

Great.

I haven't found a way to get rid of the focus square in the viewer yet. Very annoying.

 

[paulinventome]

Evin has done a big comparison 

(see http://www.reduser.net/forum/showthread.php?180359-Full-Frame-Cinema-Shootout-2020 if i'm allowed to post this?)

He included the fp for curiosity, old firmware though. The results are nice, bearing in mind you're competing with Alexa Mini LF et al. Shows that hand held the sigma is too light but IMHO it does pretty well bearing in mind it's a tiny fraction of the cost. I'm not 100% convinced post was done the best it can be, but there you go.

I was going to check out the dynamic range as i've just about sorted my chip chart out. It reckon it's 12 stops. The sensor output is pretty linear.

I know sigma are working on firmware update so i hope it's not too far away - they promise they *are* listening!

cheers
Paul

[Lars Steenhoff]

which number is the fp in that video?

[rawshooter]

From the outdoor scene it's almost impossible to judge (too much handheld, too much background blur, too much out-of-focus shooting, lack of fine textures/details).

 

From the studio scene:

• It can't be 1 (because the scaling/downsampling of small details/text is too clean compared to the Sigma's odd Bayer-to-Bayer downscaling);
• it's unlikely 2 (because details in this image look too artificially sharp, like it was shot with a conventional codec)
• It can't be 3 (for the same reasons as 1)
• It could be 4 - because the fine details are so blurry, just as with the 4K RAW from the 6K sensor of the fp.
• It can't be 5 (for the same reasons as 1 & 3)
• It can't be 6 (see above, although there's moiré in the fine details)
• It can't be 7 (see above)
• It can't be 8 (see above)
• It might be 9 because fine details are blurrier and showing moiré, but still too good IMHO

So either 4 or 9, more likely 4.

 

From the overexposed studio scene:

• 4 looks likely, since the Sigma fp really has no log profile and no highlight roll-off to speak of when the image clips.
• 9 looks too good for being that overexposed...

So I'd say it's 4. The weird flashing artifacts of the underexposed studio scene are an indicator of the fp as well, if this was shot with the old firmware.

 

- If it's 4 indeed, then it confirms what we already observed; that the Sigma fp has rather poor Raw video quality for a full frame camera and is significantly worse than the rest. If it's not 4, it would be a pleasant surprise.