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Thank you for sharing TaxiDiver. Those are actually great videos, especially for an out of the box first time experience. I hope the diver in the pool (00:53) is OK though :)

 

Was steady shot on? What was your lens?

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The diver is ok hehehe. That was a Discover Scuba for Dawn Sindrome kids and I had a great day with them.

 

Steady allways on. Lens FE 16-35.

 

No lights(only on second video). AWB (Color Matrix A+3, M+4).

Edited by TaxiDiver14

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Thanks to you two for posting. I appreciate it and will digest your posts, and films, and respond. Since Taxidiver was kind enough to post his films, I thought I would throw together some of the recent 4K footage shot in the Gulf of California. I show two clips twice to illustrate a comparison of Raw footage and some post processing (not touting it, just showing you how footage shot without a picture profile can be edited for color correction in Premiere Pro).

 

Ammar: You comprehensive post is awesome. In particular I would like to get back to you on the picture profile issue.

 

 

Thanks,

 

GLP

Edited by GeoPaul7
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Beautiful video George. The blue is well, blue. What did you different this time than your first video test that had a magenta tone?

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TaxiDiver:

 

On the test movie I supplied both RAW and Corrected, one after the other, so that people could compare. I did that with 2 clips, so you will see 4 clips in the little movie -- two versions of each file.

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Beautiful video George. The blue is well, blue. What did you different this time than your first video test that had a magenta tone?

Thanks Ammar:

 

On the first video with the magenta cast, I was trying my best to do a custom white balance, at 60 or 70 feet, and now I know that you really can't do that with this camera. In addition, I think I did the balance and then ascended a little, so whatever I did, was done at 15 to 20 feet deeper than where I took the video. This is the only explanation for the magenta cast (supplied by a guy at Backscatter in Monterrey, California) that I have contemplated that makes any sense to me. That was the first time I had used that camera and I was a raw beginner (not much better now).

 

This dive trip to the Sea of Cortez did not occur in such strong currents as the Cozumel trip, and I was able to concentrate on the photography a bit more than when chasing the dive master and my girlfriend in a drift dive. In addition, I got bifocals for my dive mask prescription, and this has allowed me to see the controls on the camera much better -- and the monitor screen too. It makes a huge difference!! I have learned that you really do need to monitor what you are shooting. If the thing is going wrong, you can see it in the monitor -- for example with the exposure and with the white balance too.

 

Here, I was NOT using a picture profile. I was using a "Magic Filter" (like I did in Cozumel) but was using the camera's underwater auto white balance. It works sometimes and sometimes not, depending on the location of the sun, and the quality of the light. And as I mentioned to TaxiDiver, there are two versions of each file -- one RAW and one corrected -- so you can see the extent to which you can correct files that are not shot in a picture profile.

 

My take away is that when shooting wide angle in ambient light far underwater, you try your hardest to get decent colors into your RAW footage, even if not done with complete technical accuracy like one would do in a controlled environment in a studio. It seems like Canon and Sony have radically different approaches to color balance. I don't know what kind of program or algorithm Sony uses for its underwater auto white balance, but they are doing something interesting. It even seems to compose colors on the fly. But it is finicky and unpredictable.

 

Then, as long as the RAW footage is close enough to your version of reality, that you want to convey in your film, you do the color correction. The RAW footage only needs to be close enough to give you your results. But this must all be done in a spirit of abstraction, and an attitude that reality, and color, is somewhat subjective in any event. That appears to be the Sony approach. I have not yet tried the Canon cameras but from what I have read and heard, they take a much more quantitative approach, and are able to handle far greater color temperatures.

 

Ammar:

 

I would be extremely interested in your sLog 2 experiments. May I suggest that you do some experiments shooting the same scene with and without the picture profile? Then we can test whether there is any real benefit to shooting in a log profile The jury is still out for me. And there are disadvantages. I don't think you can take a custom white balance in the sLog 2 picture profile, so you need to take one (if you are doing it that way) and then switch profiles. And, you will need to switch to take photographs as well. These experiments regarding picture profiles are really on the cutting edge in my opinion, but everything seems to start with white balance. It is the sine qua non.

 

I don't know where I got that magenta cast but it was so strong I could not get it out even in post (not real experienced there I admit).

 

Many thanks for continuing to follow this thread.

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Ok I got it. On second clip when you correct you push up magenta too much on whites. You can see it on ths sun ball.

Yes I agree. I was not really trying to do a final version, just sort of roughing it out to show what you can do. Many strange things happen when you start fiddling with the colors and levels.

 

On a different note, I am very impressed by your Down's syndrome work. That is awesome and a great way to utilize your diving and photography skills. I love your editing and use of music as well!

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Thanks Ammar:

 

On the first video with the magenta cast, I was trying my best to do a custom white balance, at 60 or 70 feet, and now I know that you really can't do that with this camera. In addition, I think I did the balance and then ascended a little, so whatever I did, was done at 15 to 20 feet deeper than where I took the video. This is the only explanation for the magenta cast (supplied by a guy at Backscatter in Monterrey, California) that I have contemplated that makes any sense to me. That was the first time I had used that camera and I was a raw beginner (not much better now).

 

This dive trip to the Sea of Cortez did not occur in such strong currents as the Cozumel trip, and I was able to concentrate on the photography a bit more than when chasing the dive master and my girlfriend in a drift dive. In addition, I got bifocals for my dive mask prescription, and this has allowed me to see the controls on the camera much better -- and the monitor screen too. It makes a huge difference!! I have learned that you really do need to monitor what you are shooting. If the thing is going wrong, you can see it in the monitor -- for example with the exposure and with the white balance too.

 

Here, I was NOT using a picture profile. I was using a "Magic Filter" (like I did in Cozumel) but was using the camera's underwater auto white balance. It works sometimes and sometimes not, depending on the location of the sun, and the quality of the light. And as I mentioned to TaxiDiver, there are two versions of each file -- one RAW and one corrected -- so you can see the extent to which you can correct files that are not shot in a picture profile.

 

My take away is that when shooting wide angle in ambient light far underwater, you try your hardest to get decent colors into your RAW footage, even if not done with complete technical accuracy like one would do in a controlled environment in a studio. It seems like Canon and Sony have radically different approaches to color balance. I don't know what kind of program or algorithm Sony uses for its underwater auto white balance, but they are doing something interesting. It even seems to compose colors on the fly. But it is finicky and unpredictable.

 

Then, as long as the RAW footage is close enough to your version of reality, that you want to convey in your film, you do the color correction. The RAW footage only needs to be close enough to give you your results. But this must all be done in a spirit of abstraction, and an attitude that reality, and color, is somewhat subjective in any event. That appears to be the Sony approach. I have not yet tried the Canon cameras but from what I have read and heard, they take a much more quantitative approach, and are able to handle far greater color temperatures.

 

Ammar:

 

I would be extremely interested in your sLog 2 experiments. May I suggest that you do some experiments shooting the same scene with and without the picture profile? Then we can test whether there is any real benefit to shooting in a log profile The jury is still out for me. And there are disadvantages. I don't think you can take a custom white balance in the sLog 2 picture profile, so you need to take one (if you are doing it that way) and then switch profiles. And, you will need to switch to take photographs as well. These experiments regarding picture profiles are really on the cutting edge in my opinion, but everything seems to start with white balance. It is the sine qua non.

 

I don't know where I got that magenta cast but it was so strong I could not get it out even in post (not real experienced there I admit).

 

Many thanks for continuing to follow this thread.

And in addition, when shooting in sLog picture profile, it is much harder to monitor, because of the flatness of the monitor as it has yet to be "delogged" YOu must use that Gamma display assist and I wonder how accurate that is as far as monitoring the footage. That too will be an interesting experiment.

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Thank you George for the info. I find custom WB underwater a pain in the neck. Tried it once when I bought my Canon 5DM II rig back in 2008 and never again.

 

Yes sure, this is a great idea, will shoot as you suggested with both S-log2 and without.

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A little of morning WORK...

 

e1ff9664c604eae3788eefea0a141320.jpg

Very nice. What program is that? You look like you are working with a vectorscope.

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Thank you George for the info. I find custom WB underwater a pain in the neck. Tried it once when I bought my Canon 5DM II rig back in 2008 and never again.

 

Yes sure, this is a great idea, will shoot as you suggested with both S-log2 and without.

Ammar: I am going diving in the Caribbean in two weeks, and I will try that experiment as well. I hope to get really excellent results there with the ambient light, given the clarity. I will try some comparisons of the picture profiles. Any reason you are shooting in S-Log2 rather then S-Log3?

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George. Sony A7RII does not have S-Log3 like the A7SII. I would have gone with the S-Log3 profile without a doubt if my cam has it as it captures more dynamic range and much better for grading as the reviews suggest.

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Ammar, I think you have to be very careful about SLOG2/SLOG3 shooting underwater on the A7 cameras. Because SLOG is NOT raw. What slog is doing is trying to squeeze in a broader luminance/chrominance range in the same 8-bit 4:2:0 100mb/s video container, unlike RAW photos, where a JPEG is 8-bit 4:2:2 compressed image and the raw is 14-bit 4:4:4 (kinda, it's actually the luminance level for each sensor pixel, which you debayer to color information when you process the raw).

 

There's a couple of important implications to this. First, SLOG2 has a baked-in white balance, just like a JPEG, and unlike a RAW. So whether you shoot with no picture profile or SLOG, you still have to get the white balance right at the time of acquisition. You will have much less flexibility to correct it later than you would with a RAW photo file, or even with a JPEG file (since JPEG is 4:2:2, it records twice as much color information as the video, which is 4:2:0).

 

Second, because SLOG is trying to squeeze in a much larger color and luminance range into the same container, you end up using fewer bits to represent luminance/color variation. Which, in practice, means you have LESS room for fine color corrections in post with SLOG footage than with no picture profile footage. Plus, the colors are just off. Now, I'm not a great colorist by any means, but in my experiments shooting the same scene with no picture profile and SLOG underwater, the no picture profile image looks much better both right out of camera and after post-processing -- better saturation, better color accuracy, etc. Yes, you have to be careful to expose correctly for the main parts of the image and you will get some parts that are blown out, but the properly exposed parts will look good -- if you get the white balance right. With SLOG, none of it looks right, and adjusting it in post still doesn't produce an image as nice as the no picture profile image.

 

I'll try to post a few examples of footage I've shot recently with ambient light (shallow) in UAWB mode and with artificial light (a bit deeper) later this week. After using this camera on 100+ dives, including 50+ video-focused dives, I'd say it IS possible to get very nice footage from it. But you have to get it in camera as much as possible, relying on post-processing for minor adjustments (minor levels and contrast, primarily, rather than color shifts).

 

Since I got the Gates GT14 lights, I've also tried to do some shooting with lights in UAWB mode -- the results are interesting. Generally, setting custom white balance to the lights (5200K for me) is better if you're shooting a scene where the lights are the primary source of illumination (subject <0.3m away, depth 20m+). However, if shooting wide angle in shallower depths or where the subject extends beyond 0.5m away, you actually can get decent color shooting in UAWB mode with the lights on. Of course, just like if you were shooting with a red filter and lights, if your subject gets too close to the lights, the red is going to be emphasized a bit too much. So Sony's UAWB mode is not smart enough to dial the red boost down if there's a strong source of warm light in the scene. But for scenes where the lights provide a more limited fill, the overall balance is actually not bad.

 

When I get a chance (and get the right filters), I'm going to try to put some blue gels on the lights to cool them down and see what results I can get shooting with gelled lights and UAWB mode. I'm expecting this might actually produce the most pleasing images in the 10-20m range, or even below 20m. Above 5 meters, especially with clear water and a sunny day, the UAWB mode works really, really well with or without a filter.

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dreifish, truly appreciate the info. Most valuable.

 

Actually I thought that Slog was like shooting RAW and wasn't aware of the technicality you stated thankfully. So, there is no profile in the cam to shoot video in RAW like mode? Do you recommend shooting video in standard mode based on your experience?

 

As I said I'm totally new to the video profiles thing thus still exploring how to get the best out of it.

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If I may just add one more argument to that great summary from dreifish for not shooting SLOG underwater: Due to its curve SLOG is not really ideal for low light situations and you are much more likely to get blocking and noise.

 

This is due to the fact that in SLOG you got lots of dynamic range at the highlights, but this comes at the expense of not so much dynamic range in the lowlights / midrange. However, as protecting highlights is not the key issue for underwater filming I would use "normal" or Cinegamma Settings (PP5 or 6 on the A7SII if I recall correctly) instead.

 

If you want to dig deeper on the subject of Sony's picture profiles and gamma curves, there is some excellent write up by Alister Chapman on his blog http://www.xdcam-user.com.

 

bubffm

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As promised, here is some rough-cut footage shot on my A7RII as part of a series I'm doing on the different dive sites in Komodo National Park.

 

The first video is shot entirely using ambient light and underwater auto white balance mode, no picture profile. Depth of the site varies from 3-12 or so meters. Some of the deeper shots (e.g. the turtle, lion fish) are shot using a green water magic filter. The shallower shots such as the coral are shot with no filter. Minimal color correction done in Final Cut Pro X.

 

https://youtu.be/LoQCtNUDCcg

 

The second video is shot using two Gates GT14 lights, mostly in Custom White Balance (5200K). A couple of shots, like that of the anemonie and the sweet lips are in underwater auto white balance mode + the lights. No filters were used.

 

https://youtu.be/j3UgK5OOaV8

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bubfff.. thank you very much for your helpful input. The Cine profile looks promising. Will try that indeed.

 

dreifish.. thank you for the video. I was only able to see the first one as for the second one I keep getting "Private" message. The 1st video is beautiful. Colors are amazing. Slightly off perhaps in my opinion with the turtle and lionfish clip due to the magic filter for sure.

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As promised, here is some rough-cut footage shot on my A7RII as part of a series I'm doing on the different dive sites in Komodo National Park.

 

The first video is shot entirely using ambient light and underwater auto white balance mode, no picture profile. Depth of the site varies from 3-12 or so meters. Some of the deeper shots (e.g. the turtle, lion fish) are shot using a green water magic filter. The shallower shots such as the coral are shot with no filter. Minimal color correction done in Final Cut Pro X.

 

https://youtu.be/LoQCtNUDCcg

 

The second video is shot using two Gates GT14 lights, mostly in Custom White Balance (5200K). A couple of shots, like that of the anemonie and the sweet lips are in underwater auto white balance mode + the lights. No filters were used.

 

https://youtu.be/j3UgK5OOaV8

Thanks Dreifish. I agree the first video is amazing! That is underwater white balance and no filter? That sure opens up possibilities, as one could use lights on the same dive, without surfacing to take off the filter.

 

Question: How deep do you think you can go with the Underwater white balance able to do the job -- without a filter? How shallow can you be and still use the underwater auto white balance, rather than auto white balance? AGain, your video here is something to aspire to, and I love the drone shot too!

 

I can't see the second video either. Would love to see it!

 

Thanks for posting!

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By the way gents... did anyone of you used a fisheye lens on the A7S or A7R cam?

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By the way gents... did anyone of you used a fisheye lens on the A7S or A7R cam?

I used the Nauticam "Wet wide angle lens." and a 28 mm inside the housing. They don't describe it with an equivalent mm, but rather they say it gives a 120 degree view. I haven't tried to determine what mm equivalent that is.

 

I personally would be interested in comparing the quality of the Nauticam Wet wide angle with something that was exclusively Sony on the inside of the housing. I just accepted the advice of the Backscatter saleman.

As promised, here is some rough-cut footage shot on my A7RII as part of a series I'm doing on the different dive sites in Komodo National Park.

 

The first video is shot entirely using ambient light and underwater auto white balance mode, no picture profile. Depth of the site varies from 3-12 or so meters. Some of the deeper shots (e.g. the turtle, lion fish) are shot using a green water magic filter. The shallower shots such as the coral are shot with no filter. Minimal color correction done in Final Cut Pro X.

 

https://youtu.be/LoQCtNUDCcg

 

The second video is shot using two Gates GT14 lights, mostly in Custom White Balance (5200K). A couple of shots, like that of the anemonie and the sweet lips are in underwater auto white balance mode + the lights. No filters were used.

 

https://youtu.be/j3UgK5OOaV8

Hi Andrei: What lenses were you using, particularly on the first, as I can't see the second yet? thanks.

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Thanks for all that technicall info. As I said slog is not for UW shooting. Camera right out of the box is good.

 

Yes you will have issues with WB. But get it easy...

 

Using lights AWB playing a litle with color matrix.

 

No lights UAWB playing with color matrix depending on water colour and depth.

 

In my old NEX6 (do not has PP nor UAWB), that perform well.

 

What I have seen in sony sensors is that you allways need to add red in post. So I will play with PP adding some red saturation an reducing some green. But this will be latter.

 

Im finishing editing my last trip to Red Sea with the NEX6 and I will post the raw and corrected clip.

 

Thanks you all for helping, this in being very interesting post.

Edited by TaxiDiver14

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