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Q for DX-2G users--beating backscatter?

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I took my DX-2G + YS-01 strobe out for its first dive today. Conditions were poor, vis was about 15 ft.

 

Every shot had significant backscatter, except for the closest macro shots. It seems like I'll really need to black out the internal strobe to prevent this. But is the internal strobe important for the camera's TTL calculations? I am not sure how that works. The YS-01 doesn't preflash. (Or does it?)

 

It is also possible that I have my expectations set wrong. Even with an external strobe set far away from the camera, maybe it's just futile to try taking wide-angle shots in poor visibility.

 

I have been diving with a camera for a long time, but never with an external strobe until today. Operating the camera is not a problem, but I am not sure how to aim the strobe for best effect. This it not something the manual covers at all.

 

Thanks for any advice!

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In principle the backscatter is you lighting up the junk between your lens and your subject. By proper aiming your strobes and using only the outer edges of your beam to hit your subject you can significantly reduce lighting up the junk between. The trick is to aim your strobes outward where they need to be in reality, not where you think they are aimed because of your vision behind the flat glass of your mask. I would recommend to test your strobe aiming in a pool at night and see where your beam hits at various distances. After a while it becomes second nature :D .

 

Good luck and practice makes perfect,

 

Cheers,

 

Bo

 

I took my DX-2G + YS-01 strobe out for its first dive today. Conditions were poor, vis was about 15 ft.

 

Every shot had significant backscatter, except for the closest macro shots. It seems like I'll really need to black out the internal strobe to prevent this. But is the internal strobe important for the camera's TTL calculations? I am not sure how that works. The YS-01 doesn't preflash. (Or does it?)

 

It is also possible that I have my expectations set wrong. Even with an external strobe set far away from the camera, maybe it's just futile to try taking wide-angle shots in poor visibility.

 

I have been diving with a camera for a long time, but never with an external strobe until today. Operating the camera is not a problem, but I am not sure how to aim the strobe for best effect. This it not something the manual covers at all.

 

Thanks for any advice!

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I took my DX-2G + YS-01 strobe out for its first dive today. Conditions were poor, vis was about 15 ft.

 

Every shot had significant backscatter, except for the closest macro shots. It seems like I'll really need to black out the internal strobe to prevent this. But is the internal strobe important for the camera's TTL calculations? I am not sure how that works. The YS-01 doesn't preflash. (Or does it?)

 

It is also possible that I have my expectations set wrong. Even with an external strobe set far away from the camera, maybe it's just futile to try taking wide-angle shots in poor visibility.

 

I have been diving with a camera for a long time, but never with an external strobe until today. Operating the camera is not a problem, but I am not sure how to aim the strobe for best effect. This it not something the manual covers at all.

 

Thanks for any advice!

 

If the internal strobe is still putting light on the subject then that explains why you got no improvement with the external strobe. The internal strobe must be blocked or you really are not accomplishing anything.

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If you have the whitish plastic adaptor the same as the 1G then I would suggest you black it out to stop the internal strobe affecting the photo. I have the 1G and I painted the adaptor black - leaving the holes for the fibre optic cable clear to stop this.

 

Then as the others said - correct placement of your external strobe should reduce the backscatter.

 

Karl

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The 2g has a diffuser that rotates down into place, inside the housing. But the whole top of the camera lights up anyway. The backscatter from the internal strobe is no surprise really when you look at it. I wonder why they did not provide a means to black out the internal strobe?

 

Karl, do you shoot TTL or manual?

 

A couple of times I tried blocking the internal flash with my fingers, but I think it confused the TTL system. The external strobe went to full power on those occasions. I'll have to do some experimenting on dry land.

 

On another forum someone suggested using some exposed slide film as a filter for the internal flash, as it will pass only IR.

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The 2g has a diffuser that rotates down into place, inside the housing. But the whole top of the camera lights up anyway. The backscatter from the internal strobe is no surprise really when you look at it. I wonder why they did not provide a means to black out the internal strobe?

 

Karl, do you shoot TTL or manual?

 

A couple of times I tried blocking the internal flash with my fingers, but I think it confused the TTL system. The external strobe went to full power on those occasions. I'll have to do some experimenting on dry land.

 

On another forum someone suggested using some exposed slide film as a filter for the internal flash, as it will pass only IR.

 

Actually you want unexposed, but developed, slide film.

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If you have the whitish plastic adaptor the same as the 1G then I would suggest you black it out to stop the internal strobe affecting the photo. I have the 1G and I painted the adaptor black - leaving the holes for the fibre optic cable clear to stop this.

 

 

I did exactly the same. I blacked out the strobe adapter with a black sharpie. no scatter from the internal flash. I was shooting TTL but have recently switched to manual. I had no probs with TTL.

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Karl, do you shoot TTL or manual?

 

Unfortunately with the 1G I can only shoot in Av mode because the LCD screen goes too dark to able able to focus on your subject when in low ambient light :D - otherwise I would love to able able to shoot in manual. Plus I use twin YS27 strobes which are fully manual (no TTL setting).

 

Hoping to upgrade to the 2G in the near future.

 

Karl

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Unfortunately with the 1G I can only shoot in Av mode because the LCD screen goes too dark to able able to focus on your subject when in low ambient light :) - otherwise I would love to able able to shoot in manual. Plus I use twin YS27 strobes which are fully manual (no TTL setting).

 

Hoping to upgrade to the 2G in the near future.

 

Karl

 

 

Im using the 1G too. Speaking about upgrades, How do 1G and 2 G compare on noise and particularily high iso noise?

 

The dark screen sure is an issue, hower I'm often trying to shoot balanced light. Then I do see the image on the screen, but what you see is not what you get in my opinion, I think the screen is brighter than the actual result. (Anyone else agrees) So I need to realy only use the shistogram, which I tend to forget now and then.

 

 

My opinion is that even 200ISO is significanlt noisier than 100 (too noisy) and 400 unusable. Your opinions?

 

 

/O

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Im using the 1G too. Speaking about upgrades, How do 1G and 2 G compare on noise and particularily high iso noise?

 

The dark screen sure is an issue, hower I'm often trying to shoot balanced light. Then I do see the image on the screen, but what you see is not what you get in my opinion, I think the screen is brighter than the actual result. (Anyone else agrees) So I need to realy only use the shistogram, which I tend to forget now and then.

 

 

My opinion is that even 200ISO is significanlt noisier than 100 (too noisy) and 400 unusable. Your opinions?

 

 

/O

 

 

200 is as far as i would prefer to go. i have shot at 400 but only when i have aboslutely had to in low light conditions. Tho I am not pleased with the images. heavy de noising in lightroom 3 is needed after shotting at 400

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Following up with my results...

 

I realized that my strobe aim on my first outing was awful and probably caused the vast majority of the backscatter I saw. I still completely blocked the internal strobe with duct tape outside the housing for my next try, because it can't hurt and may help. On the second outing I didn't get any great pictures, but I did make progress and was able to take some photos with good lighting and no backscatter. The strobe technique will just take practice.

 

Also, and this may be old news, I realized that the DX-2g + YS-01 combo will work great with the camera is set in manual mode and the strobe is set on TTL. I thought I would have to use aperture priority, but the DX-2G's TTL system was perfectly happy with me setting the aperture and shutter manually. Most of the time I left the camera at f/8.1 and shutter 1/125. With a little bit of negative flash exposure comp, overall exposure was generally good.

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