New Article - Strobe Use w/ Digital Cameras

Hi Gang,

I've written a column about strobe use with the various consumer digital cameras. The article can be found here:

http://wetpixel.com/features/200211_strobeuse/

The beginning of the articles starts with 2 comparison photos - one taken with a 100w video lite and the other with dual strobes. You can see some interesting differences.

Hope you all find this useful.

Cheers

James

Hello James,

First, thanks for the great articles... very helpful.

I recently decided to take the plung and try u/w digital. I already own the Coolpix 995 and have decided to go with the Aquatica housing setup with the wide angle lens. I have used the Nikonos V for a few years with a single SB105 strobe. I know the Nikonos strobes and sync cords are compatible with the Aquatica housing. I have never quite got the hang of using the strobe in manual to achieve proper exposure and now being a newbie with the digital underwater I would like to keep it less complicated in the beginning. My question is to do with the TTL. I have read some forum discussions on TTL and the Ikelite and Aquatica housings. Some suggest that with the Aquatica you are not able to use TTL because the sensor is blocked. ??? Can you shed some insight on this please? Also, is the SB105 suitable with the Aquatica and for wide angle?

Thanks

Yes it is sadly true. You can NOT shoot TTL with the Aquatica because the "ttl" sensor is blocked. The sensor is not actually inside the lens, it's that little black hole on the popup flash.

The Ikelite housing provides TTL capability with your camera.

HTH

James

Well,,, guess I will have to learn to go manual. I have already ordered the Aquatica. Have you used this housing? I know that when using the w/a that TTL doesn't do it so would need to go manual, but what about when doing macro? I always used the TTL on the Nikonos.

oooops! guess I didn't do enough homework before ordering the Aquatica.

Well, you only have full, 1/4 and 1/16 power on the SB105 so you are going to have a bear of a time getting good macro exposures. If 1/16 power at your highest F-stop is still too much light (and it may well be) you will get to learn about diffusers and about moving your strobe back. I guess you'll just have to wait and see.

Another alternative would be to get a YS90DX

Have you received the housing yet?

Cheers

James

I've did some shooting with the 995/Aquatica combo. I used a SS200 set at 1/8, which was often too much power. You may want to shoot at 1/16 power or 1/4 with a diffuser.

I'm used to a housed film camera. You spend and hour or so getting everything ready, but when you jump in the water, it's f22 and TTL...fire away, with maybe an fstop change along the way. Same with a Nikonos when shooting macro.

I practiced with CP995 to try an minimize the number of exposure adjustment to get it right. It was never easy. I stuck with a shutter speed of 1/125 and adjusted my f-stop. This is kind of an ass backward approach, but with the smaller CCDs, depth of field never seemed a problem throughout most of the f-stop range. I chose this approach, because 1) it was easier to get fractional f-stop adjustments versus shutter speed and 2) the f-stop range changes with focal length anyway.

Alternately, if you set the shutter and aperture, you could use the EV control to adjust, which may give better results. I recall it taking a fraction of a second longer to ajust the EV than the f-stop.

I found this easier than adjusting strobe position or strobe power. Reaching up to your strobe all the time is a pain, but of course, I adjust strobe position on almost every shot nowadays.

Here are the only keepers from my limited use. The keeper rate was pretty low, but a couple were darn good, while most were just OK.

Digital Images

Thanks for all the good info...

James, I have already ordered the Aquatica and is being shipped as we speak. I am not too familiar with the YS90DX. Would I have more flexibility with this strobe compared to my SB105? I do use a diffuser mainly when shooting w/a with my Nikonos. But from what you said that even if used at 1/16 power at the highest fstop if shooting macro it could still be too much light? It was easy with Nikonos taking macro, set it at f22 and TTL, and as scorpio_fish said, "fire away". This may be a dumb question, but if the TTL does not work with the Aquatica since the sensor is blocked, then whats the point of the "TTL sync cord" connection? If I want to use TTL, will I need a TTL slave sensor even with the YS90DX?

Scorpio_fish, nice pixs by the way. I appreciate your tips and will put them to use on my upcoming trip. I feel pretty comfortable with shooting manual with my cp995, but just not sure how it will all work with my SB105... will be all trial and error I am sure.

Thanks a lot you all....

Hi Caroline,

The first thing that you need to understand is that there is shooting Manual Camera vs Automatic and there is shooting Manual Strobe vs TTL. For example, you can shoot Manual Camera and TTL with a strobe or Aperture Priority with the camera and Manual strobe...etc.

Now, you asked why you need a sync cord if you can't use the TTL on your strobe. That's pretty simple really - the camera will tell the flash to fire, through the sync cord - however it won't tell it WHEN TO STOP. That's why YOU have to set the power on the flash yourself.

You can use guide numbers to do this. If you are shooting a macro subject at one foot at f8 - then you want to set your strobe power to a guide number of 8. You shot a Nikonos, so hopefully you own the Jim Church book. Time to start reading up on guide numbers!

HTH

James

Hi James,

Thanks for the added info. I guess I did come across as being totally in the dark. One problem I have is I don't have as much opportunity these days to go diving and each time I go its like learning all over again almost. This will be my first attempt using the digital and housing. I just want to be sure I have the right strobe for my setup. I do have the Jim Church book and has been my bible in learning u/w photo. Good advice, I will study the guide number section I was getting the impression that the SB105 could be too much power if wanting to shoot macro. I am curious about the YS90DX. I see it has a built in diffuser so good for wide angle, but wonder if it would give me more flexibility otherwise, i.e. shooting macro at lower power.

By the way, this is a great website,,, very impressed with the wealth of experience I have found here

Thanks

Caroline

Caroline,

I have the A995 and YS-90DX. I am really a newbie to underwater photography, but most of my shooting has been at night. At night is just about the only chance I get to go diving nowadays, although I am off to the Southern Egyptian Red Sea next month…YIPPEEEE! But I digress.

What works for me for night photography is with the camera on manual I set the shutter speed to 1/125s (this is immaterial really) and I set the aperture at f7.5. With this setting, the f-stop does not change when you zoom the lens in and out, so you can be assured of a consistent setting all the time. I then control exposure from the strobe’s power setting, and for a shot, say at 10-12 inches distance to the subject, the medium setting on the strobe, with the diffuser on, is about right. I have obtained some perfect, predictable exposures this way.

Of course, the YS-90DX allows you to do this because of the 12 (I think) power settings it provides.

HTH

John

Woody and Caroline:

If I remember correctly, you need to go into the camera's menu and set it to constant F-stop when you zoom. Otherwise the Fstop will go up and down when you zoom.

That's the way my 990 works, so I'm assuming the 995 is the same way.

Cheers

James (bored at work) Wiseman

Thanks so much, John for your tip.

btw- I am very jealous of your trip to the Red Sea!! wow. That will be awesome... I hope to get there sometime next year. I am off to Cozumel for Thanksgiving this year,,, not nearly as exciting as the Red Sea... I have heard wonderful things about it.. will you be doing a 'live-a-board'?

I think your suggestions on the settings will be very helpful. I currently have a SB105 and I am starting to think it may be worth the investment to get the YS-90DX because of the setting flexibility. I don't want to find myself missing too many opportunities due to messing with the strobe settings and exposure settings. I am new to digital and my cp995 and am getting familiar with all the various settings.... so would be nice if I didn't have to worry about the strobe so much.

I welcome any words of advice on both strobe and cp995..... I am so glad I discoverd this website.....

here's to great diving.... in the Red Sea.

Caroline

James,

Good point!! I believe you are right about that... on the Fstop changing when zooming.

Thanks..

Here comes the rain in Florida......

Caroline

James, that is correct. I forgot to mention it. Of course, even with this setting, if the lens is say zoomed too far for a specific aperture, then the camera will still change the aperture.

Caroline, my Red Sea trip will be a liveaboard on the Coral Queen. 7 days unlimited diving!

http://www.coralqueen.com

Sorry, couldn't help it!

Caroline -

The YS 90 DX is great for digital (or any other non-TTL applications) because it allows you to choose between 12 strobe power levels. Perhaps someone will inform us both as to what the minimum power is equivalent to - is it really that much less than 1/16 on the SB 105? I don't think that with the strobe on minimum and your aperture stopped down you will over-expose macro shots. The YS90 would give you some added flexibility, but your system should function well as is. Further, you might look into the YS90auto - this strobe may not be available yet, but it promises to offer TTL functionality independently of the camera. It sounds like this solution might suit you best, and be worth waiting for.

Kasey

[What works for me for night photography is with the camera on manual I set the shutter speed to 1/125s (this is immaterial really) and I set the aperture at f7.5.]

When shooting macro, you should try to maximize your f-stop. Since you seem to have more than enough strobe power, you should be shooting at the camera's max f-stop (min aper) for all macro. This will give you max depth of field and color saturation.

Kasey

Kasey,

You are right of course, but with the Coolpix 995, f7.5 is in fact the smallest aperture that you can use when the lens is at its widest setting, so if you want to have a constant, smallest aperture throughout the complete zoom range this is the smallest you can go.

When in macro mode, with the lens set at the widest setting at the limit of the macro "sweet spot" (i.e. when the flower is yellow, for those who own a Coolpix), the minimum aperture is f9.4.

John

And since you get about 5 times the DOF of a film camera, that ~f9 is just fine. Heck, it's great in fact! Even at f9 w/ the coolpix I get more DOF than with my S2/60mm at f22!

Cheers

James

Hi Guys,

Have any of you tried shooting close-ups with the wide angle on the cp995?

After many comments on the YS90DX I have decided to go for it. It does sound like I'll have more flexibility with it. All I have known so far in u/w photo is the Nikonos V with SB105, used the 20mm and 28mm. This has been an education since I made the decision to try digital. All the tips have been great. I'll be going to Cozumel in a week and can't wait to see how I do. One thing with the YS90DX that I see is it has a built in diffuser. Will this be good with the w/a, especially since I'll be using one strobe for starters?

John, the live-a-board sounds great. I have done some live-a-boards and such a great opp for photo experience.

Happy diving.....

Caroline

Caroline,

The "built in" diffuser on the YS-90dx is the same as on the SB105. It's that "dimpled" clear thing over the flash tube.

The strobe does come with a removable opaque diffuser as well.

I'm sure you will be happy with your new strobe.

Depending on which wideangle lens you use with your coolpix, you should be able to focus very close.

Cheers

James