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Interceptor121

What is the right focal length for video?

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Interceptor,
Did you ever shoot one of the PMW-EX1 or EX3  cams in a gates back in the day? Seems it wasn't that long ago that this was THE way to get the best quality underwater. Time moves on.

John most of the ‘evolutions’ are dictated by what else is available. Until a few years ago lights were limited to 60 degrees so working with narrow lenses was the norm for close shots
Then 90 degrees lights came around and now you have 120 or even 150 degrees lights. Video has traditionally been rectilinear with no distortion so when cameras like the GH5 have cone around the first choice has been 7-14 mm lenses to match the new lights except 7-14 performs really badly in the edges when you go finning. So now the solution to that is fisheye like lenses that are distorted but dont pull corners in the shape of wacp wwl-1 etc.
Optical performance remains largely unaffected by evolution in sensors generally a rectilinear lens too wide will have perspective distortion on any camera body.
I wrote this post to explain it


https://interceptor121.com/2019/10/13/using-rectilinear-wide-lenses-underwater/

So 18mm equivalent once in 16:9 has no corners issue for most if you wanted to use a rectilinear lens in water and still be wide this is as far it goes offering 90 degrees horizontally
If that is not enough (and for most cases it is enough) you can go WWL-1 way the field of view increase is not 30 degrees as diagonals dont matter but 14 degrees on the horizontal compared to a rectilinear 100 degrees diagonal lens so the effective field of view increase is 28% not 80% if you look at diagonal
If you think about it this means a frame 2.57 meters wide instead of 2 meters
In any case in my opinion a removable optic with zoom like the WWL-1 remains preferable when you have larger subjects because the range of focal length you cover is huge but am not that sold on WACP fixed ports for video
So when I need to shoot rectilinear because I don’t have large subjects and mostly have people in the shots I like to have a lens like the leica 12-60 that gives me plenty of flexibility otherwise wwl-1 is my choice. I tend not to use the 8-18mm in video as 18mm is too wide for close ups for my taste


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Nice information there - thanks !

So what do you think about the P6K with the WACP port? Which Canon lens would be your go to in that scenario?

I know you dont like RAW but I am at the 180 degree opposite opinion to yours on this. I think RAW is the best thing sliced bread.

I've mentioned it before but I will say it again.....given all the time and cost that goes into a dive (I mean, honestly..what is the cost per dive when you add up all the gear you own and how quickly it dies and needs replacing if you dive often enough and even worse, if you dont dive much since it then cost so much more per dive if you used it little, plus the cost of travel and air fill's etc to get down to the site you are videoing ?) a bit of time correcting and tweaking images to be the best they can seems trivial to me.

To put this into perspective, I am currently building a new editing PC. Its been 10+ years since I built my last PC so its time to upgrade (yay!! i'll be able to keep 100 plus Chrome Tabs open at a time !). I am trying to get an AMD 3950X 16 core into the case I have along with a 2080Ti video card. With or without video editing this is the rig I will build. It will carry me for another 10 years (I hope). So for editing that 6K BRAW I will be in good shape. I already have a 4U SuperMicro server with 36 x 6TB HDD's in it for storing footage plus looking into getting an 48 tape LTO tape library for writing footage out to tape for long term archiving (not much difference in cost between a 48 tape library and a standalone LTO 8 tape drive, so may as well get the library machine). To give you an idea on cost of LTO 7 tapes formatted to LTO 8 the cost per TB is around $6.00. Yes, that is $6.00 per Terabyte. Not so heavy. The Tape Library is 6K so its an investment for sure but if you plan to shoot enough footage it pays over time. So the sheer amount of data generated by the P6K is not that big a deal to me.

What is a big deal is getting out to the dive site, gearing up and diving safely to get the shots. Not to mention that over time doing many dives the cost is quite large to do those dives.

So to me the cost of the camera rig seems to be the smaller part of it all.

So with all that gibberish out of the way, what would you say is the ideal setup for the P6K? Which lens with which port. Being able to zoom through from 10mm to 25mm seems ideal with the WACP, but is there another way to do this that you deem better?

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@JohnDoe who said I do not like RAW? Unlike most people here in the video section I shoot stills maybe I am even a better photographer than I am a video guy listening to the feedback. I use RAW all the times with still images however my workflow for still images is not focused on white balance. In fact as a photographer you know that if you don't the colour right in the shot at least on a good part of your subject using a strobe or ambient light when you white balance it looks weird. In fact in most cases the reason why I white balance ambient light shots is because I did not white balance at time of shooting, then the white balance is right later corrections are minimal. What RAW gives you is the ability to exploit the dynamic range of the camera much more, underwater you tend to shoot underexposed according to the camera to avoid clipping highlights as camera metering fails in many situation due to blue water scattering light. So then you push up you darks and stretch the image to bring it back to the detail that seemed to be missing in the first place. After you get this right the next steps are local adjustments like graduated filters, brushes etc etc. Usually you spend much more time on local adjustments than you do on exposure. 

For video is a bit different as you are moving around in most cases and video tools do not offer the same ability to perform local adjustments. What you are left is exposure and white balance. For white balance what I said before holds if you use lights the adjustments are minor if you don't you need to adjust in camera. The other items is the ability to bring the dynamic range back into the picture that is probably the most important part however if you lock exposure this will only work well on a static scene. It is crucial for video to get the exposure right in camera and actually I am not a believer of fixed exposures. If you set a fixed exposure and you move around you have a risk of clipping the highlights or crushing the blacks here with a RAW editor you can recover to an extent. Otherwise you set a variable exposure for example set aperture and shutter and leave ISO float this will make sure you don't have huge variations reducing the need for the raw adjustment later.

It goes by itself that unless you have backlit scenes you can nail exposure and white balance in camera and in fact many of my still images have only local adjustments for things I could not fix in camera.

Regarding your question on the WACP it vignettes until 20mm so out of 18-55 you get 20-55 x 1.4 crop x 0.36 = 10-27 mm fisheye am not sure how useful is the range between 17-27 mm for you but the alternative is to forget the WACP entirely and go on Canon EF mount for APS-C

 

So instead of your WACP you could get

1. Sigma 17-70 mm (as this is cropped sensor I would not get the 8.5 acrylic dome and settle for the 180mm glass dome need to work out the extensions) this gives you 24-98 mm rectilinear which for most cases this is all you need

2. Tokina zoom fisheye 10-17 mm this gives you the same of WACP if you need more zoom you put a kenko teleconverter

With the WACP you still have to cover normal angles and macro so the cost of the set up above will be significantly less as the Tokina takes a compact acrylic port

I do not own this camera nor I plan to buy it however as I said before I would not be looking at the WACP personally if I had to

 

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On 11/20/2019 at 12:03 PM, Interceptor121 said:

For video is a bit different as you are moving around in most cases and video tools do not offer the same ability to perform local adjustments. What you are left is exposure and white balance. For white balance what I said before holds if you use lights the adjustments are minor if you don't you need to adjust in camera. The other items is the ability to bring the dynamic range back into the picture that is probably the most important part however if you lock exposure this will only work well on a static scene. It is crucial for video to get the exposure right in camera and actually I am not a believer of fixed exposures. If you set a fixed exposure and you move around you have a risk of clipping the highlights or crushing the blacks here with a RAW editor you can recover to an extent. Otherwise you set a variable exposure for example set aperture and shutter and leave ISO float this will make sure you don't have huge variations reducing the need for the raw adjustment later.

Sorry to disagree but I do :) Pretty much all tools available for photos are available for video you just need the right software and processing power. Is it more time consuming? Yes it is but you can do it.

As for the auto stuff it works much better if you just slow down a bit, plan what your shot is going to be and fix your exposure. If you are a bit out you fix it in post. Please note the word a bit. But if you plan it it will be a bit and not blown out which is usually the problem rather than be too dark. Otherwise get a go pro and shoot from the hip :) (not you Interceptor its a generic coment)

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1 minute ago, Lionfi2s said:

Sorry to disagree but I do :) Pretty much all tools available for photos are available for video you just need the right software and processing power. Is it more time consuming? Yes it is but you can do it.

As for the auto stuff it works much better if you just slow down a bit, plan what your shot is going to be and fix your exposure. If you are a bit out you fix it in post. Please note the word a bit. But if you plan it it will be a bit and not blown out which is usually the problem rather than be too dark. Otherwise get a go pro and shoot from the hip :) (not you Interceptor its a generic coment)

Pretty much does not mean same and moving around creates complexity.

But this is all academic as I have yet to see a single impressive clip shot with a camera with CinemaRaw or Blackmagic Raw underwater that has had all the adjustments done to it that looks amazing. I think there is a significant difference between a staged shot like a commercial film on land and shooting underwater

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11 minutes ago, Interceptor121 said:

Pretty much does not mean same and moving around creates complexity.

But this is all academic as I have yet to see a single impressive clip shot with a camera with CinemaRaw or Blackmagic Raw underwater that has had all the adjustments done to it that looks amazing. I think there is a significant difference between a staged shot like a commercial film on land and shooting underwater

What local adjustment you can do in a photo that you cant do in video? Agreed on the complexity.

BMPCC 4K is not the best choice IMO for UW video that is why not so many people use it at the moment and so not many clips available. Video RAW codecs to consumer market is relatively new very few cameras offer it and very few people know how to properly exploit it. As time goes by and more cameras start to offer it people will use it learn it and get the benefits.

I am not talking about staging the shot I am talking about thinking the shot which doesnt take that long. Its the same with photo, you see the subject think the settings you ll use adjust and make the shot. Why acting differently when doing video? 

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Thinking the shot is key of course.

Local adjustments I use regularly are:

Brush I can brush parts of the frame as I wish and then apply the whole set of exposure white balance sharpness etc to that area. I have not see this

Graduated filter: as above on a line with a gradient

Radial filter: I have seen this but is the least useful

Control points: click on a point and perform adjstments on similar pixels I have seen this but is not really useful

So I would say the key ones are the graduated filter and the brush those I can't find anywhere the others I can but they are not useful as the previous two

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2 hours ago, Interceptor121 said:

Thinking the shot is key of course.

Local adjustments I use regularly are:

Brush I can brush parts of the frame as I wish and then apply the whole set of exposure white balance sharpness etc to that area. I have not see this

Graduated filter: as above on a line with a gradient

Radial filter: I have seen this but is the least useful

Control points: click on a point and perform adjstments on similar pixels I have seen this but is not really useful

So I would say the key ones are the graduated filter and the brush those I can't find anywhere the others I can but they are not useful as the previous two

You really need to start learning and using resolve (btw the new cut page is almost the same like FCPX so the editing is the same).

Graduated filter: available in the colour page with one click

Brush: create freeform windows and do changes isolating anything outside them. You can track the windows if there is movement

Radial filter: Same as graduated filter

Control points: lots of tools to do qualifications and perform the same.

 

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What your brush example does is a mask and that is not useful a freehand brush is used to correct an area and stop the brush as you describe it is also available in FCPX and is useless. The other issue is that once you brushed your object it moves in the frame 

Same issue with graduated filter if you change the angle it moves

At the end you frame the shot correctly and expose you avoid most of those. When you shoot stills instead you push the camera as you have more selective controls see above

I would like so see something done in resolve that explains me the benefits above and then understand how long it takes to achieve them

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26 minutes ago, Interceptor121 said:

What your brush example does is a mask and that is not useful a freehand brush is used to correct an area and stop the brush as you describe it is also available in FCPX and is useless. The other issue is that once you brushed your object it moves in the frame 

Same issue with graduated filter if you change the angle it moves

At the end you frame the shot correctly and expose you avoid most of those. When you shoot stills instead you push the camera as you have more selective controls see above

I would like so see something done in resolve that explains me the benefits above and then understand how long it takes to achieve them

Re brush and graduated filter use tracking it will follow whatever you want to follow you can do it manually too but the its rotoscoping and we are talking vfx which you can do in fusion or after affects. You can also assign keyframes. The tools are there but it takes time to learn them I agree.

Agreed that your best strategy is to think the shot and expose it correctly.

 

Edited by Lionfi2s

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Why so you all think the P4K is not so good for underwater? 12 Bit RAW. Whats not to love? P6K even bettter - room to reframe and stabilize shots. Whats not great about that?

I understand if you have a GH5 and sunk a ton of $$$ into that rig that you may say there is no huge LEAP above what the GH5 can do so you will pass on the p4k. I get that. But why do you say its not that great underwater? Its surely no worse than the GH5.

If only you will bite the bullet Interceptor and get into a P6K rig..........

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15 minutes ago, John Doe II said:

Why so you all think the P4K is not so good for underwater? 12 Bit RAW. Whats not to love? P6K even bettter - room to reframe and stabilize shots. Whats not great about that?

I understand if you have a GH5 and sunk a ton of $$$ into that rig that you may say there is no huge LEAP above what the GH5 can do so you will pass on the p4k. I get that. But why do you say its not that great underwater? Its surely no worse than the GH5.

If only you will bite the bullet Interceptor and get into a P6K rig..........

John I take stills not just video and I think the video I shoot has margin for improvement to do with my skills. I don't feel like my clips need more technological power I just need to shoot better videos

In terms of suitability people that shoot on land (check out wolfcrow) say after using it that the BMPC4/6K are not suited for documentaries but for small commercial projects and studio work which is not the underwater environment I dive in so I think even if I had the money (and I do) I would not buy it. Right now am just starting to understand the capabilities of AVCI 400 mbps and they are significant I do not think I am missing anything for the little I do

When I compare my clips with others including pros is not the image quality that is lacking but my storytelling ability 

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...and THAT is the crux of it...the story telling. Have a compelling story to tell and no cares what you shot it on. 

Having said that, nice tools do help. If we can get a bit more dynamic range, more bit depth so that we can change from one colour into another with no banding etc. A lot of this has already been achieved. It's no longer the HUGE leap forward. Now its tiny steps forward.

While I get your point entirely, wouldnt be able to reframe with oodles of room to spare help you tell a better story? Wouldn't being able to zoom in on something much tighter then you originally shot it help with accentuating a part of the story you are trying convey? (in post I mean, because you have all that extra res the 6K gives you...especially if you are delivering a 1080p deliverable)

Sure you can do all this manually by just shooting it right......while underwater you manage all the other things that your life really do depend on down there. Your workload down there is high. Years of experience helps one manage all this, but surely it is nice to be able to zoom in without losing res to get closer to that shy animal or reframe a shot (in post) because you got it ever so slightly wrong (while 40 metres down) etc.The P6K allows all this. Its no panacea to the perfect clip by any means - just more useful and nice to have tools that help out along the way. 

At the end of the day its mostly about the skill of the shooter. But those tools can help polish things even tighter. And that is my point.

I just bought a new boat and outboard and that has dented the account balance somewhat. Next problem is, on my beach it is so rocky that I cant actually pull the boat up onto my beach. So now i have to build a jetty. It never ends. I just bought a D800 rig, so going to console myself with that for a while, but I have every intention of getting into the P6k in a Naughty cam. I just dont see the value in a Red costing 10x more. Underwater we have natures thick filter holding back the best of glass. Water. 800 times denser then air. What a damm filter we have to deal with! By time I get the jetty done and I can actually use my boat and get out to my dive spots maybe the P8K will be here....who knows? But I can say BlackMagic have surely opened pandora's box to allowing the average man to access higher bit depth RAW. 

Who knows what the GH6 wil be? Its a fast moving target for sure.

Edited by John Doe II

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I typically hang on to my cameras for too long. I have had the GH5 for 1 and half year and I think I will be looking at changing it in 2021

Plenty still to optimise out of what I have and no I don't need dynamic range or more colours than what I already have right now I just need to shoot better and more so rather spend money on trips

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ahhh well you see that is a major difference. Where I dive is outside my back door. The only money I spend to go diving is the air compressor and fuel for the outboard.

I am with you on hanging onto camera gear. Once I get whatever video shooter I get I also wont be upgrading to get 2% better quality out of the chip. There is a point where enough is enough.

But I do think the P6K underwater is the revelation we have been waiting for. S35 sensor. 12 Bit RAW. 6K. beyond that I cant see how it can be improved a whole lot more in the next 3-5 years. I think it will be all optical improvements from here on out. WACP is proof of that. I think more companies will get on this bandwagon. And there are supercomputers to crunch the numbers in simulations. I think thats the next big leap forward.

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oh and lights. Let's not forget lights. Advances in LEDs are incredible.

I want a bright light with a wide beam angle with a CRI of 99 and it should be able to run for 3 hours on a not yet invented battery tech. That battery should be small, recharge fast and have 3000 recharge cycles. Electric cars are pushing battery tech forward at a hard and fast pace. So much money to be made to whoever gets there first.

 

Edited by John Doe II

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John you don't need a wide beam angle I can cover the field of view of the WWL-1 with two 95 degrees lights actually you could cover it with 90

There is a lot of marketing hype out there for features people do not need. This distracts from learning how to actually use what you have and shoot properly

 

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I have found Weefine/kraken to be pretty decent. Build quality as well as quality of light is pretty decent in my eyes. Most likely are Keldans are better, but double the price better? I doubt it. At least for the low/mid range lights. No idea about the top end.

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We are digressing from the key topic here which was the right focal length for video

Now if for most you are ok with 24 mm in 35 equivalent which is 84 diagonal you don't need excessively wide lights

In terms of what lights you need this depends on your field of view so if you shoot a fisheye you will not be able to cover the whole field of view but you will need very wide lights

120 degrees like the keldan is a very wide beam I have found that at same lumens I prefer a narrower beam. 95 degrees covers perfectly my WWL-1 so I do not need wider.

In terms of chinese light they differ what is important is the LED array in terms of quality then you need to look at ergonomics.

My ideal light is a 95 degrees keldan but it does not exist I think gates does 95 degrees lights but they are very bulky

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1 hour ago, John Doe II said:

are the chinese lights any good or should we stick with Keldans/Gates etc ?

They are good enough (for most).

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Interceptor, agree we are digressing here but it is all interrelated. Best lens in the world is not much use without all the right parts to go with it.In fact its generally a waste to take a high end PL mount lens down below.

Lens, Dome and particularly new cutting edge water contact optics combo's are the thing that is going to change our underwater world, closely followed by lights.

Lens design is not changing to any significant degree going forward. What focal length behind which optic (dome/ WW-1 or WACP or Nikonos) is going to be where all the changes happen. In my humble opinion of course.

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John

I have been advocating water contact optics since years

I tested the nauticam wwl-1 prototype and gave them the feedback that brought very soon the float collar and bayonet system to the market

Water contact optics are not new both wet and dry however one needs to be factual of what is that you actually get

To say that a non rectilinear water optics has a magnification of 0.36x is misleading

I have all sort of tools but dry mounts like the WACP have never convinced me

 

 

Sent from my iPhone using Tapatalk

 

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