shooting with the underwater housing at DVinfo.net

Steven Kornreich · December 20th, 2002, 02:26 PM

I just started using my UW housing with my MX5000 and had a few question in regards to focus.
I went out the other day on the back of my jetski and had my mx5000 set up with auto focus on and I used manual exposure.
I noticed when I got home that the focus drifted in and out sometimes so I thought maybe I should try manual focus, but of course using the pana uw housing there is no way to adjust the manual focus. SO my question is, if I first decide on a zoom setting then don't touch that, is it better to use a slower shutter speed like 250 and a smaller iris setting like F11 or what is the best way to go?

Steven Khong · December 22nd, 2002, 08:58 PM

Actually I don't have experience with underwater housings. But I've got some experience trying to shoot through glass, plastic, wire fences / chicken wire etc.

When your MX500 goes out of focus, it could be because it was focusing on the drops of water on your casing. Try putting some Rain-X, that MIGHT help - but don't get it on your rubber seals, just in case it reacts!

Maybe it was trying to focus on the waves which was moving too much, and got confused. The autofocus (at least on my MX300) focused best & quickly on objects with sharp contrast & at most, moderately slow moving.

Also you can try using as high a shutter speed as possible - especially so if you jetski! This also makes the aperture as big as possible, so there is less depth of field. There is a "sweet spot" in regards to aperture - not the max, and not the min, where the lens performs best.

What I would do is to use Manual focus, then put the focus as far as possible i.e. infinity or even a little before infinity is possible if your aperture is not fully open. This makes sure that the cam doesn't focus on nearby objects i.e. the dust on your glass, plastic, fences etc. But this makes vidcamming nearby objects like your jetski instrumentation near impossible.

By focusing at infinity, your cam will make far away objects sharp & focused, while nearby objects i.e. drops of water, inperfections or streaks on the glass out of focus & almost inconsequential. You can see this on land if you try to vidcam past a wire fence.

Now, if you put your MX500 on as wide as possible, this helps because 1) you get to capture more / wider angle 2) less camera shake is apparent.

It's good to try these settings on land before you go out to sea.

Hope that helps, and all the best!
Steven Khong

Steven Kornreich · December 23rd, 2002, 01:33 AM

So basically first set the focus manual to near infinity, set aperature to lets say F8 that's like in the middle (sweet spot) then use what ever shutter speed to optain correct exposure and shoot?

Steven Khong · December 23rd, 2002, 03:03 AM

Yes! ... except for the aperture part...

1) Widest angle
2) Manual focus to near infinity or at infinity
3) High shutter speeds i.e. 1/750 onwards
4) Hopefully aperture not at F16 or even F11...

I'm not very familliar with the MX5000 though, so I can tell you what to do on MX300 & hope the MX5000 can do it.

On my MX300 in Manual mode, I have to set the shutter speed first, then only I can set the F stop. My MX300 CANNOT set the F stop first & then allow me to choose my speed. In SLR camera terms, the MX300 is Shutter priority & not Aperture priority. So in this case, I would set a high shutter speed i.e. 1/1000 & let the camera figure out the correct aperture.

But be careful that if you set the shutter speed too low, even if the cam sets to its max F16, there might still be too much light going in the cam. You'll eventually learn by trial & error, given time you will be good at getting the right shutter speed, through experience.

I also have a "trick" to see what the aperture the cam has chosen - by pressing the jog wheel again after setting the shutter speed, it shows you what aperture the camera has chosen, then I quickly press the jog wheel again to let it go back to shutter speed setting. Also, holding down the jog wheel for like 2 to 3 seconds turns off the manual adjustment of shutter speed & aperture, and you are back in Auto exposure. Don't know if your underwater casing allows you to do this though.

For intense sun, experiment with Neutral Density filters. The colors will come out deeper & the glare is lessened as well. They will also move your exposure down from F16 to something like F11, F8. ND8 would be a good start.

Now, about the sweet spot... it may not matter much in the end, unless you have very sharp eyes & a real perfectionist - You can tell the difference if you compare the videos shot at F16 with the same video, same scene shot at F8. There is a slight difference. Does it matter? Your audience isn't going to compare the two videos with you, right? You don't have to keep worrying about the aperture dropping out of the sweet spot so much. Just enjoy shooting the video!

Maybe the Sports mode can help - it would set the cam to very fast shutter speed & lower F stops - you are at the cam's mercy though... Do some test recordings, then playback the tape, look at the information that the cam shows what shutter speed & aperture was used.

Good luck!

December 27th, 2002, 09:49 PM

Can someone point me to where i could buy an underwater housing for the mx500?

Frank Granovski · December 28th, 2002, 12:53 AM

There are 2 members here who live in Japan, and are willing to buy cameras and gear for people who want them. So contact either Tim or Allan.

December 20th, 2002, 02:26 PM	#1
Steven Kornreich Regular Crew Join Date: Aug 2002 Location: Kamas, UT Posts: 25	shooting with the underwater housing I just started using my UW housing with my MX5000 and had a few question in regards to focus. I went out the other day on the back of my jetski and had my mx5000 set up with auto focus on and I used manual exposure. I noticed when I got home that the focus drifted in and out sometimes so I thought maybe I should try manual focus, but of course using the pana uw housing there is no way to adjust the manual focus. SO my question is, if I first decide on a zoom setting then don't touch that, is it better to use a slower shutter speed like 250 and a smaller iris setting like F11 or what is the best way to go?

December 22nd, 2002, 08:58 PM	#2
Steven Khong Regular Crew Join Date: Dec 2002 Location: Petaling Jaya, Selangor, Malaysia Posts: 112	Actually I don't have experience with underwater housings. But I've got some experience trying to shoot through glass, plastic, wire fences / chicken wire etc. When your MX500 goes out of focus, it could be because it was focusing on the drops of water on your casing. Try putting some Rain-X, that MIGHT help - but don't get it on your rubber seals, just in case it reacts! Maybe it was trying to focus on the waves which was moving too much, and got confused. The autofocus (at least on my MX300) focused best & quickly on objects with sharp contrast & at most, moderately slow moving. Also you can try using as high a shutter speed as possible - especially so if you jetski! This also makes the aperture as big as possible, so there is less depth of field. There is a "sweet spot" in regards to aperture - not the max, and not the min, where the lens performs best. What I would do is to use Manual focus, then put the focus as far as possible i.e. infinity or even a little before infinity is possible if your aperture is not fully open. This makes sure that the cam doesn't focus on nearby objects i.e. the dust on your glass, plastic, fences etc. But this makes vidcamming nearby objects like your jetski instrumentation near impossible. By focusing at infinity, your cam will make far away objects sharp & focused, while nearby objects i.e. drops of water, inperfections or streaks on the glass out of focus & almost inconsequential. You can see this on land if you try to vidcam past a wire fence. Now, if you put your MX500 on as wide as possible, this helps because 1) you get to capture more / wider angle 2) less camera shake is apparent. It's good to try these settings on land before you go out to sea. Hope that helps, and all the best! Steven Khong

December 23rd, 2002, 01:33 AM	#3
Steven Kornreich Regular Crew Join Date: Aug 2002 Location: Kamas, UT Posts: 25	So basically first set the focus manual to near infinity, set aperature to lets say F8 that's like in the middle (sweet spot) then use what ever shutter speed to optain correct exposure and shoot?

December 23rd, 2002, 03:03 AM	#4
Steven Khong Regular Crew Join Date: Dec 2002 Location: Petaling Jaya, Selangor, Malaysia Posts: 112	Yes! ... except for the aperture part... 1) Widest angle 2) Manual focus to near infinity or at infinity 3) High shutter speeds i.e. 1/750 onwards 4) Hopefully aperture not at F16 or even F11... I'm not very familliar with the MX5000 though, so I can tell you what to do on MX300 & hope the MX5000 can do it. On my MX300 in Manual mode, I have to set the shutter speed first, then only I can set the F stop. My MX300 CANNOT set the F stop first & then allow me to choose my speed. In SLR camera terms, the MX300 is Shutter priority & not Aperture priority. So in this case, I would set a high shutter speed i.e. 1/1000 & let the camera figure out the correct aperture. But be careful that if you set the shutter speed too low, even if the cam sets to its max F16, there might still be too much light going in the cam. You'll eventually learn by trial & error, given time you will be good at getting the right shutter speed, through experience. I also have a "trick" to see what the aperture the cam has chosen - by pressing the jog wheel again after setting the shutter speed, it shows you what aperture the camera has chosen, then I quickly press the jog wheel again to let it go back to shutter speed setting. Also, holding down the jog wheel for like 2 to 3 seconds turns off the manual adjustment of shutter speed & aperture, and you are back in Auto exposure. Don't know if your underwater casing allows you to do this though. For intense sun, experiment with Neutral Density filters. The colors will come out deeper & the glare is lessened as well. They will also move your exposure down from F16 to something like F11, F8. ND8 would be a good start. Now, about the sweet spot... it may not matter much in the end, unless you have very sharp eyes & a real perfectionist - You can tell the difference if you compare the videos shot at F16 with the same video, same scene shot at F8. There is a slight difference. Does it matter? Your audience isn't going to compare the two videos with you, right? You don't have to keep worrying about the aperture dropping out of the sweet spot so much. Just enjoy shooting the video! Maybe the Sports mode can help - it would set the cam to very fast shutter speed & lower F stops - you are at the cam's mercy though... Do some test recordings, then playback the tape, look at the information that the cam shows what shutter speed & aperture was used. Good luck!

December 27th, 2002, 09:49 PM	#5
El Pollo Loco Posts: n/a	Can someone point me to where i could buy an underwater housing for the mx500?

December 28th, 2002, 12:53 AM	#6
Frank Granovski Outer Circle Join Date: May 2002 Location: Hope, BC Posts: 7,524	There are 2 members here who live in Japan, and are willing to buy cameras and gear for people who want them. So contact either Tim or Allan.