Irwin

I came with the "self healing" feature, the housings do not.

Thank you, sir, I'll take that as your blanket endorsement.

I agree, but my issue was with being too close to begin with. No, I haven't tried to do so. Even though it was slightly soft, my favorite shot so far was with the 17-40 and that was with the Ike 6" dome without a diopter. A few questions on your 16-35, +4, 6" combination. Did you always use that combination or was the +4 added based on results obtained without it? Would you expect the Ike 8" dome to provide me the same improvement with my 17-40 that you see with the +4 ? What else will a diopter affect? DOF, focal length/distance, etc. I've done some additional land tests and have learned from them just what you're saying. I've decided that AI Focus is the better choice for macro. One Shot would be the second choice. I don't see that AI Servo has any value for macro. As to keeping the subject in the AF point, for me the 10D viewfinder made that next to impossible. The 5D will improve what I see.

Yes, I was using the 100mm macro I almost certain I was too close. I mistakenly believed that the shutter would only fire when focus lock was present. Not so. This was with a 10D. The tiny viewfinder, multiplied by the housing optics, didn't allow me to see much of the image - definitely not enough to judge crisp focus vs. nearly focused. The 5D is going to improve what I can see through the viewfinder, including the focus lock light.

I've also used a 10D and I agree the 5D's AF seems better than the 10D. The sharpness is unquestionably better, due no doubt to the better sensor.

All, I didn't mean to imply that there was wrong with either the 5D or 10D. I don't doubt at all that it was my fault to begin with and I'm working toward correcting both my technique and having everything set appropriately to begin with is a prerequisite. Generally I don't have focus issues u/w but I have had out of focus close-in shots, with both the 100mm macro and the 17-40. I've done some additional land testing (with the 17-40) and found that both AI Servo and AI Focus will track the subject but, when getting closer than the lens' minimum distance, they will still take an out of focus shot. When starting out to close to begin with, AI Servo will take an out of focus shot but One Shot and AI Focus will not. Stu, can you elaborate on you choice of AI Servo rather than AI Focus ? -Irwin

As I recall, it might have been Ike himself, but I can't find the actual reference. Good to hear a couple of people haven't had any bad experiences. Anyone else ?

Problem is the 5D will confirm autofocus occasionally even when it's not actually in focus.

I have yet to use my 5D underwater but I expect to have the same autofocus problem that I had with the 10D, i.e.: autofocused shots were out of focus - specifically at close range with macro or WA lenses. Every mode appears to be able to take an out of focus shot though I not always able to get it to do so. I can always get AI Servo to take out of focus shots and the 5D knows it's not in focus: no beep or confirmation light. I'd like to hear from anyone that has determined the best autofocus mode to use or the situations in which to use which mode.

I believe Ikelite discourages using their housings in swimming pools due to possible reactions between the plastic and the chemicals. Does anyone have actual experiences with this ? -Irwin

I don't think I need to won't have to worry about which fisheye I want as Canon only has one, a 15mm. Prehaps someone else manufactures a ~10mm EF mount lens? Do I assume correctly that the 1.6x factor for the 10D affects the minimum focal length, not the angle of view which is listed as HxVxD 141°54' x 91°44' x 180°. But the angle might be affected by port and water ? I guess I'm wondering how much better the 15 FE would be over the 17-40 (assuming each has the appropriate, different port). Also I would think the 17-40 may be more versatile than the 15. I don't really know, I know my wreck pictures with a wide angle (INON on a Ike housed 4040) were much better than without it.

Ike does say the diopter isn't necessary so my order didn't include one. But, I suppose, the images will have to be different somehow. After you do your test, would you please post a with/without comparison shot of the same subject? I've never heard of "NL4" - what does that mean? How did you decide on +4 ? -Irwin

Thanks to all that provided a lot of in depth information. My dilemma goes unanswered (and completely ignored on uw-photo and a couple of honest "don't really know"'s on Digital Diver) though. The intended housing is an Ike DSLR. The first port will be an easy choice - for the 100mm macro. I'll also have a 17-40 mm L USM that Ike's web site says a diopter isn't required for it but I wonder if the image quality, dof, etc, would be enhanced with it. To round out the lens selection I expect to later get a fisheye but I'm undecided on which. Opinions ?

After deciding on a DSLR I waited to make the purchase until a housing became available for it. Price was the one, but not the only, motivating factor. The camera is now on its way but I'm thinking twice about the housing. I've realized that the port functions as a lens element so it's optical quality has to be considered. Is there much variation in the optical quality of ports from the name-brand suppliers? Am I too concerned about this? -Irwin

I think that for flash bracketing to work with ANY strobe, the camera has to be able to wait for the strobe to indicate it's ready as any strobe could have a weak charge and a slow recycle time. And, as my DS-125 preflashes, flashes, and recycles just about as fast as I can press and release the trigger, I think it's possible