Why are 4k cameras sharper than some best 1080p cameras like F3?

On the exposure topic, mirrorless made it so easy to shoot in Manual. Thanks to live EVFs and back displays you virtually get WYSIWYG.
 
zlfan said:
I just take an initial photo, check the histogram on lcd, and retake another after adjusting the exposure. Typically two shots are enough, at most three shots.
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For video? You're setting exposure by taking photos and looking at histograms?
What camera are you doing this with?
 
Doug Jensen said:
For video? You're setting exposure by taking photos and looking at histograms?
What camera are you doing this with?
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No, not for video. I mean I use some still cameras and mf lenses, and I expose by histogram. The cameras I use are like Fuji S3 pro, Mamiya 645 with Kodak Pro Back.
For video, I use zebra, and with s log or c log, I set to 75% ire, as you suggested before. Thanks.
 
Tim Peck said:
"the exposure does not change much during several hours of the day"
Sorry but you just contradicted yourself there.
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In my city this is the case, I did many event sessions using manual exposure, and get this conclusion by hands on experience. Under the direct sunlight, it is very difficult to expose the human face right, manual exposure is the best way to do this. I used to do in camera metering, but later found out that manual exposure is more consistent. For video, as there are tools like zebra, waveform, and realtime histogram, actually it is easier to do manual exposure. For raw video, it is a little bit more difficult, because of the ettr, luckily some cameras have usable auto ettr.
 
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AmbiSonde said:
I didn't think you were a food guru? Hot cakes!

If Sony does bring compressed RAW in their next series of cameras they will also come with all of Sony's magic autofocus developments which could make next-gen cameras real competition for RED.

I was initially extremely sceptical about autofocus, in my experience it had never worked in video and even the best would blip out of focus ruining shots. Well, the autofocus in the FX30 has completely changed my mind and I understand the new A6700 has further improved the system. The autofocus is now so reliable you're crazy not to take advantage of it, it feels like it's one step ahead of the user unlike the old systems which were two steps behind. I realise I'm late to the Sony autofocus party but it is one of the biggest changes I've ever noticed in camera developments in my career.

I expected the image out of the FX30 to be much better than the FS7 but biggest surprise has been the reliability of autofocus which was completely unreliable in the FS7 to being 99.9% reliable in the FX30, it's a culture shock for someone who never used autofocus in the entirety of their career. I was able to track one of my friends walking through a busy street towards the camera with people obscuring his face and the camera held focus all the way right up to the camera. I would never have attempted that shot with manual focus, I would probably have ended up cutting that shot in two with a cutaway just to cover my focussing mishaps. The game has changed while I've been away.

I wonder how long it'll be before Cooke makes their first autofocus cine lens for cine cameras with AI autofocus systems?
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Sony FX30 may have slight edge over Panny GH6 on video af tracking. But GH6 can export hdmi out 6k 60p braw and prores raw, and S16 cinema 4k raw 120 fps. This is much better than FX30. I think Sony should upgrade its firmware to export 6k raw. Also GH6 can record on SSD drives. At the same price range, it is no brainer for me to choose GH6.
 
In addition to the previous mentioned olpf and codecs, I just realize that in camera sharpening may play a role. For example, F3 S log 2 1080p SR444 looks softer than FS7 Slog2 XAVC 300 4k, even though F3 has a sensor of 12.9 mp, and FS7 has a sensor of 10 mp. Maybe there is certain in-camera sharpening even in slog 2. Just a guess. No real comparison test done.
 
zlfan said:
F3 S log 2 1080p SR444 looks softer than FS7 Slog2 XAVC 300 4k, even though F3 has a sensor of 12.9 mp, and FS7 has a sensor of 10 mp. Maybe there is certain in-camera sharpening even in slog 2. Just a guess. No real comparison test done.
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I don't know where you are getting your information from but it is incorrect.

First of all, the F3 and FS7 have the exact same sensor size: Super35. Where they differ is sensor resolution. The F3 is a HD camera and has a pixel count of 3.5M (total) and 3.4M (effective). The FS7 is a 4K camera with a pixel count of 11.6M (total) and 8.8M (effective).
 
Doug Jensen said:
I don't know where you are getting your information from but it is incorrect.

First of all, the F3 and FS7 have the exact same sensor size: Super35. Where they differ is sensor resolution. The F3 is a HD camera and has a pixel count of 3.5M (total) and 3.4M (effective). The FS7 is a 4K camera with a pixel count of 11.6M (total) and 8.8M (effective).
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Hello, Doug: Actually Alan Roberts at BBC did a test on F3 and concluded that the F3 sensor is about 12.9 mp. I don't know why Sony labels F3 as 3.5 mp.

"This fits reasonably well with the estimations in section 1.2.1, and means that the sensor has approximately 12.9 Megapixels, typical of a digital stills camera."

https://tech.ebu.ch/docs/other/WHP034-add68_rev_1_sony_pmw-f3.pdf
 
zlfan said:
Hello, Doug: Actually Alan Roberts at BBC did a test on F3 and concluded that the F3 sensor is about 12.9 mp. I don't know why Sony labels F3 as 3.5 mp.

"This fits reasonably well with the estimations in section 1.2.1, and means that the sensor has approximately 12.9 Megapixels, typical of a digital stills camera."

https://tech.ebu.ch/docs/other/WHP03...ony_pmw-f3.pdf
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Well, he's wrong and I'll bet you cannot find any other source that claims that number. But thanks for letting us know your source. Notice that his opinions are peppered with "must be" over and over again, so he he's just trying to peice together what he thinks is facts and jumping to a lot of conclusions. Somewhere he made a mistake in his math or assumptions about the camera. My numbers above are correct.

Even the F55 and F5 have a photosite count of only 11.6M (total) and 8.9M (effective). Do you seriously think that Sony gave the F3 (an HD only camera that came out years before the F55) a sensor that has 50% higher resolution than the 4K F55? That is ridiculous.

And why would Sony falsely claim the F3 is lower resolution than it actually is? It makes no sense.
 
Doug Jensen said:
Well, he's wrong and I'll bet you cannot find any other source that claims that number. But thanks for letting us know your source. Notice that his opinions are peppered with "must be" over and over again, so he he's just trying to peice together what he thinks is facts and jumping to a lot of conclusions. Somewhere he made a mistake in his math or assumptions about the camera. My numbers above are correct.

Even the F55 and F5 have a photosite count of only 11.6M (total) and 8.9M (effective). Do you seriously think that Sony gave the F3 (an HD only camera that came out years before the F55) a sensor that has 50% higher resolution than the 4K F55? That is ridiculous.

And why would Sony falsely claim the F3 is lower resolution than it actually is? It makes no sense.
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I actually don't have a clear reason why Sony claims F3 as 3.5 mp yet Alan Roberts claims F3 as 12.9 mp. I kind of trust Alan Roberts' tests, because his tests on various cameras basically are in accordance with my experience and other users' experience.

There is a possibility that F3 has some in house debayering pattern, somehow like F35. So Sony counts F3 as 3.5 mp after the debayering. Just my guess.
 
Unlike Alan Roberts, I actually owned and F3 for a number of years and still own a FS7. I can assure you that the F3 isn't higher resolution than the FS7. But with that said, I do think that with the right paint menu choices, the F3 has an overall more pleasing picture than almost any other camera, including the FS7. In fact, I think the F3 had the best picture of any Sony camera I've ever used. But it is only 8-bit, HD, 60p, etc. so does not meet modern specifications.
 
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