Woody's Diopter

I tried out my new Sigma 50mm macro lens with my digital Rebel, Ikelite housing, and dual DS-125's. After reading tons of great information on Wetpixel, I decided to try shooting in RAW mode and see if I could learn to deal with that. I also decided to put the diffusers on the strobes, since the big boys seem to do it. I also tried to use my new Woody's Diopter.

The 50mm worked out fine once I learned to be sure that I hadn't inadvertently switched over to "limited" rather than "full", and once I learned that changing the lens from the 18-55mm that the autofocus switch tended to get nudged over to manual focus.

I suppose there's no harm in using the diffusers with two strobes and the 18-55mm lens, but I can't think of a reason to leave them on for macro. I wondered if I wasn't giving up light that I might like to have by leaving them on for the macro. Since I was setting my f-stop so that the LCD barely showed what was in the shot (dark), then it sure seems like it would make sense to make as much light available as possible.

My thinking for using an f-stop in the18-22 range was that I could maximize the depth of field for the shot, and then get my light back via RawShooter essentials - the free download that I learned about here on Wetpixel the week before my trip. I found RawShooter to be very user-friendly and enjoyed learning to work with it.

I think I've read somewhere on Wetpixel that shooting macro at just short of *over-exposure* was the way to go when shooting RAW, but I don't understand why (if I even remember it correctly).

It wasn't until part way through my second night dive on the liveaboard that I figured out why my modeling lights on the DS-125's weren't doing very well as night dive lights. (Did I mention that I'm slow?) Once I figured out how to unscrew the diffusers from the strobes - wow! I had them tied on to the strobes with the same floss that I had used earlier in the day to repair my mask strap. Alas, the strap floss broke on that night dive. Amazing how masks stay on at depth without the strap.

I found the 50mm to be surprisingly handy for fish portraits. From what I'd read here, it seemed to be implied that it could only be used as such in a pinch. I didn't find that to be true, at all.

I intitially tried using the "noodle" float thing on the strobe arms in an effort to make the 2-strobe setup neutrally bouyant. I merely slit them and popped them over the arms, assuming that they would stay without taping them. They didn't, and I lost them on the first dive. I brought extras, but didn't bother putting them on because I didn't find the slight negative bouyancy to be a problem. Plus, Blackbeard's uses aluminum tanks, and I had to go back for extra weight on the first dive, too. The Nekton, on the liveaboard trip the previous month (see the travel section for a comparison report), uses steel tanks, and I hardly needed weights at all when using only one strobe or no strobe.

My only real disappointment on the trip (other than having it cut short by Katrina) was that I couldn't make my new Woody's Diopter work. I tried it on a bunch of dives, but could never get the Sigma 50mm to autofocus with the Wet Lens in place. Woody tells me that he's never had anyone have that problem. Any ideas out there? I'm going to have another chance to try this weekend for a couple of dives at Gray's Reef off Savannah. (I *did* have water between the WD and the housing port). I would also note that one of the web sites out there on the Woody's Diopter claims 90% magnification, but Woody says it's only 20%.

Oh, and even with only about two and a half days of diving, shooting in RAW mode caused my laptop to run out of storage space. I'm betting, though, that had I shot in RAW mode on my last trip that the queen angels wouldn't have had lavender lips when shooting without a strobe.

You guys continue to cost me money. I just ordered a Sigma 15mm FE. The chart says it will work with my 6" dome port.

Kevin

Savannah

Hi Kevin,

Firstly, the reason to use a diopter is so that you can get closer to your subject, thus getting more magnification. The 50mm lens already focuses so close that you can touch the subject with your port and still focus on it...:-)

When using a diopter, you may be focusing on a subject that is a foot away, but the little markings on the lens may say something like ten feet or mor. That's what the diopter does - and you realized that when you found that you have to have the limit switch on "full." You need your lens to be able to go to infinity to use the diopter.

Not sure why it wouldn't focus for you though. My guess is that you may have been trying to take photos outside of the range of your lens+diopter. You lose your actual infinity focus when using the diopter.

What I mean is that you won't be able to focus on subjects further than about 3' from your port when using the diopter - period.

Cheers

James

How far away from the subject were you when you used the diopter? You don't leave it on during the whole dive. You add it when you're close (i.e. 1 ft or less). It's not a magic lens. It acts like a contact lens for your lens. It brings focus in closer, thus sacrificing longer distances...but that's why it's removable. You may want to try it either in a pool or just by holding it in front of your lens and see what distance you need to be for it to focus.

It's not just shooting in Macro where one strives that the histogram is biased to the right (just short of overexposure) The nature of digital sensors put more of the information in the highlight rather than the shadow portion of the image. Read this link

http://www.luminous-landscape.com/tutorial...ose-right.shtml

The diopter will only give the extra 20%...but that could mean the difference in filling the frame with a pygmy seahorse or not.

S.

I tried out my new Sigma 50mm macro lens with my digital Rebel, Ikelite housing, and dual DS-125's.  After reading tons of great information on Wetpixel, I decided to try shooting in RAW mode and see if I could learn to deal with that.  I also decided to put the diffusers on the strobes, since the big boys seem to do it.    I also tried to use my new Woody's Diopter.

 

The 50mm worked out fine once I learned to be sure that I hadn't inadvertently switched over to "limited" rather than "full", and once I learned that changing the lens from the 18-55mm that the autofocus switch tended to get nudged over to manual focus. 

 

I suppose there's no harm in using the diffusers with two strobes and the 18-55mm lens, but I can't think of a reason to leave them on for macro.  I wondered if I wasn't giving up light that I might like to have by leaving them on for the macro.  Since I was setting my f-stop so that the LCD barely showed what was in the shot (dark), then it sure seems like it would make sense to make as much light available as possible. 

I'm not exactly sure what that last part means, but you can't use the LCD brightness to judge exposure. You must use the histogram. You want as small of a gap on the right of the histogram without touching the right.

At the aperatures you're trying to use removing the diffusers for will help a lot. + it makes the modeling lights work much better.

My thinking for using an f-stop in the18-22 range was that I could maximize the depth of field for the shot, and then get my light back via RawShooter essentials - the free download that I learned about here on Wetpixel the week before my trip.  I found RawShooter to be very user-friendly and enjoyed learning to work with it.

With the 6MP digital cameras any aperature over 16 the small size of the aperature reduces sharpness. Although you gain depth of field by increasing aperature, the parts that are in focus are less sharp. By F/22 is is very noticable.

Plus, if you are shooting F/18-22 @ ISO 100 you are almost certainly underexposing because your strobes arent strong enough.

I think I've read somewhere on Wetpixel that shooting macro at just short of *over-exposure* was the way to go when shooting RAW, but I don't understand why (if I even remember it correctly).

 

It wasn't until part way through my second night dive on the liveaboard that I figured out why my modeling lights on the DS-125's weren't doing very well as night dive lights.  (Did I mention that I'm slow?)  Once I figured out how to unscrew the diffusers from the strobes - wow!  I had them tied on to the strobes with the same floss that I had used earlier in the day to repair my mask strap.  Alas, the strap floss broke on that night dive.  Amazing how masks stay on at depth without the strap. 

 

I found the 50mm to be surprisingly handy for fish portraits.  From what I'd read here, it seemed to be implied that it could only be used as such in a pinch.  I didn't find that to be true, at all.

Yes you are right. 50mm is perfect for fish portraits. The longer macro lenses are too long for this but 50mm is great for this purpose.

I intitially tried using the "noodle" float thing on the strobe arms in an effort to make the 2-strobe setup neutrally bouyant.  I merely slit them and popped them over the arms, assuming that they would stay without taping them.  They didn't, and I lost them on the first dive.  I brought extras, but didn't bother putting them on because I didn't find the slight negative bouyancy to be a problem.  Plus, Blackbeard's uses aluminum tanks, and I had to go back for extra weight on the first dive, too.  The Nekton, on the liveaboard trip the previous month (see the travel section for a comparison report), uses steel tanks, and I hardly needed weights at all when using only one strobe or no strobe.

I hate steal tanks. They are way to heavy for me. With NO weights, no camera, and 2 layers of wetsuit, I still have to put air in my BC to be neutral. I am glad Aluminum tanks are still standard in most places I've been to..

My only real disappointment on the trip (other than having it cut short by Katrina) was that I couldn't make my new Woody's Diopter work.  I tried it on a bunch of dives, but could never get the Sigma 50mm to autofocus with the Wet Lens in place.  Woody tells me that he's never had anyone have that problem.  Any ideas out there?  I'm going to have another chance to try this weekend for a couple of dives at Gray's Reef off Savannah.  (I *did* have water between the WD and the housing port).  I would also note that one of the web sites out there on the Woody's Diopter claims 90% magnification, but Woody says it's only 20%.

What was the subject distance with the filter on. Remember that no lens will focus at infinity with a closup lens(such as woody's) on. You should only use it when you are closer than the lens's native minimum focus distance. Also using the modeling light helps.

Oh, and even with only about two and a half days of diving, shooting in RAW mode caused my laptop to run out of storage space.    I'm betting, though, that had I shot in RAW mode on my last trip that the queen angels wouldn't have had lavender lips when shooting without a strobe. 

 

You guys continue to cost me money.  I just ordered a Sigma 15mm FE.  The chart says it will work with my 6" dome port.

 

Kevin

Savannah

<{POST_SNAPBACK}>

Yep, the Sigma FE works in the same port as the 18-55.

Did I miss anything??

You guys are tremendous! Every one of my questions answered, and very clearly, at that. What a boon to my learning curve!

I definitely noticed the loss in sharpness in some of my shots using those f-stops. Thanks for the explanation.

BTW, the following is further correspondence with Woody:

> Hi Kevin,

> One suggestion. If you are too far away from your subject the

> camera lens will not be able to focus using the diopter over it

> because you have put "reading glasses" on your lens with the

> diopter. Just like you putting on reading glasses. The diopter

> is meant to be used as a macro closeup accessory not full time.

> You can read better it but you cannot see much across the

> street with it. The whole reason it is so useful is that you

> can remove it to shoot subjects farther away as opposed to a

> diopter screwed into the front of your lens that cannot be

> removed (and will not let your lens focus on a subject outside

> the "reading" distance either).

> That is the only reason I can think of that you were having

> focus problems using the diopter.

> Woody

Thanks, so much, Woody. That makes perfect sense. I was racking

my brain trying to remember if I had ever actually tried using it

while I was close to my subject. I may not have. I

think that I may have only tried to test it early in each dive,

right after turning on the camera and the strobes, and probably

just training it on another diver in the distance. I got real

good at holding it in a couple of fingers in my left hand while

also holding the grip on the housing. :-) Thanks, again.

Kevin

One last problem that I ran into shooting RAW. Occasionally, like during the shark feed, I got a "busy" signal while the camera was catching up that caused me to miss a number of shots. Very frustrating. And, I had turned the strobes off for that occasion so that *they* wouldn't slow me down.

Also, I've definitely seen the sharpness problem associated with using the wrong f-stops (histogram too far from the right). Is one manifestation of this the fact that using "sharpening" tools tends to really make the photos look icky? Adding "fill light" also seems to kind of foul them up. And, it may be that using some of the "contrast" tools tends to make "color speckles" in the background show up.

Any general rules about what the retouching software *can't* do with underexposed shots? TIA

Kevin

One last problem that I ran into shooting RAW. Occasionally, like during the shark feed, I got a "busy" signal while the camera was catching up that caused me to miss a number of shots.  Very frustrating.  And, I had turned the strobes off for that occasion so that *they* wouldn't slow me down. 

The Digital rebel has the worst buffer of any dSLR(4 raws), you picked the wrong camera if you wanted a camera for sports/Acton. But still, no reason to turn off your strobes when the action gets hot. DS-125 recycles in 1 sec from full power. If you arent useing your strobes on full power they can keep up with the rebel's lowly 2.5 fps. But even if the strobes do slow your frame rate down what would you rather have 20 monotone/cyan underexposed shots or 10 colourfull properly exposed shots?

Also, I've definitely seen the sharpness problem associated with using the wrong f-stops (histogram too far from the right).  Is one manifestation of this the fact that using "sharpening" tools tends to really make the photos look icky?  Adding "fill light" also seems to kind of foul them up.  And, it may be that using some of the "contrast" tools tends to make "color speckles" in the background show up. 

 

Any general rules about what the retouching software *can't* do with underexposed shots?  TIA

 

Kevin

<{POST_SNAPBACK}>

There is only 1 thing you cant do to an under exposed shot. Increase the exposure. As long as you dont push up the exposure more than 1/2-3/4 stop you wont run into problems.

If you do push the exposure up by more than that, thouse colour speckles, called "Noise", will become more obvious . Sharpening as you found brings out the apperance more than most things, but it is not the sharpening that introduced the noise it was when you increased the exposure artifically.

You can remove noise (at the cost of some detail) with software. I have found that neat image is the easiest to use of the good noise programs. You can download a free version from www.neatimage.com.

You can remove noise (at the cost of some detail) with software.  I have found that neat image is the easiest to use of the good noise programs.  You can download a free version from www.neatimage.com.

<{POST_SNAPBACK}>

What an incredible resource you guys are! Just a few minutes after reading your latest edifying post and I'm already able to post my first attempt at trying "Neat Image". Looks like they may be a bit on the small side, though. Thanks, again, for all your help.

Kevin