Ryan is spot on with his comments, too. I didn't mean to imply the Sigma 14mm rectilinear lens is bad. In fact it's quite sharp! Flare is one of those things certain photographers whine about and others learn to not shoot into the sun at such sharp angles and thus have very few problems.
Maybe James will chime in about his "low tech" shade solution
Also, the new Ikelite 8" dome with the correct extension is something I didn't test in Australia on the Canon 5D as I donn't own a Cano 17-40L or 16-35mm. But based on 8" dome results with Canon's 10-22mm on a cropped sensor Canon camera (practically equal to the Canon 17-40L or 16-35mm on the Canon 5D full frame sensor) I'd bet the results would be acceptably sharp for most UW shooters.
YMMV !!!
dhaas
I recently shot with my 5D underwater in a modified Sea & Sea DX-30/60 with the 17-40L lens - I found that the corner sharpness was good on shots that were further back (6ft or so) but on close-focus wide-angle, the corner sharpness was a little soft (as it was with this lens on the 20D/D60). However, with a diopter (I've played with both +2 and +4) I've gotten good results - the best corner sharpness is with the +4 on close-focus shots. I'll post crops if I can pull them up. I plan to get in the pool this week with the Aquatica 5D housing, and will test sharpness then also. Hope this helps.
HooverMD in choosing the Sigma 14mm will have a really wide rectilinear lens, which as long as he doesn't include the sun at sharp angles (siince this lens flares Mucho' as posted on surface and UW forums) he might be happy with it UW. Shot at reasonable apertures (f5.6-11) it is very sharp for a non-manufacturer lens....But the Sigma 15mm Fisheye is still a better buy IMHO.
As to the flare I can attest to the issue above water for sure!
I encountered problems with the Canon 16-35 behind the Ike 6" dome(5503.55). There was a large amount of blurring (it seems to be caused by refraction) at the edges of the frame. On a 1.5 crop camera I doubt the blurring would be too noticeable. I suspect the 17-40 may suffer a similar fate.
Ike graciously offered to send me an 8" dome with a couple of stalks for testing. I'm planning on testing various combinations of ports, stalks and diopters. I’ll post the results when I’m done (I don’t have a 17-40 to test, but f someone in Wisconsin would like to find out how it works in the 8†feel free to let me know).
I encountered problems with the Canon 16-35 behind the Ike 6" dome(5503.55). There was a large amount of blurring (it seems to be caused by refraction) at the edges of the frame. On a 1.5 crop camera I doubt the blurring would be too noticeable. I suspect the 17-40 may suffer a similar fate.
Sounds like what you see when the lens needs a diopter. Next time try it with a +4 diopter and I bet you will get satisfactory results behind the 6" dome.
Do you recommend any particular brand or quality? I'm considering getting a set (+1,+2,+4) for testing.
An inexpensive set of 3 runs $70-$80. A single high quality coated diopter can run $200-$250.
No point putting a cheap diopter in front of an expensive lens. I would start off looking for B+W diopters.
Cheers
James
In low light the Canon 100mm has a hard time focusing. In these situations a manual focus port is very helpful.
I love the Canon 16-35 F2.8 on a Canon 5D and the Canon 100 Macro. The 24-70 F2.8 is really sharp as well, and will enable to have a really wide range without the super wide.
Ok, I've just purchased an almost new 17 - 40 mm f/4 lens. I will be purchasing my Ikelite case with 8" dome soon.
Thanks all for your input,
- Robert
In low light the Canon 100mm has a hard time focusing. In these situations a manual focus port is very helpful.
I have not the found the Canon 100mm to have any more problems focusing in low light than any other lens. Low light focusing issues are more related to the camera body than the lens.
I just got my 17-40mm lens for use with the 5D. It's very nice for the price, very similar to Nikon's 12-24DX f4 AFS (A $1,000 lens).
Cheers
James
I also have the 17-40L - it's a great lens. I'll post some pool shots tonight when I get done with testing it (I just got the right extension ring from Aquatica yesterday) to check corner sharpness.
Brian
I also have the 17-40L - it's a great lens. I'll post some pool shots tonight when I get done with testing it (I just got the right extension ring from Aquatica yesterday) to check corner sharpness.
How many millimeters long is the extension ring for the 17-40L?
Cheers
James
Just ordered my Ikelite equipment.
5D Housing
8" dome port
2 DS-125 Flash kits
Dual-sync cord.
Thanks all for your help!
- Robert
James -
Sorry about the delay - several exams this week in school, so I've been a little behind.
I have 2 extension rings stacked - the one for the 12-24 nikkor (#18456) and the one for the 100mm (I don't know part #). The total length of these 2 rings is 4.5cm, which looks slightly short to me (I've e-mailed Aquatica about it). My computer is fighting with me, so no crops to post, but the corners looked soft without a diopter - with a +4 they looked pretty good.
Thanks Brian, good, I'm all set then. I have those rings and I have a +1 and +4 diopter if I need one.
Cheers
James
No one has mentioned the 20mm prime lens from canon...I was considering this as my possible WA lens of choice instead of a zoom...have d70 now and the 12-24 nik and have never really been pleased with the results...but Dr. clearly seems to do very well with this lens...also does anyone else feel that the canon lenses focus faster than the nikons?
You will also want a macro lens. Either Canon 100mm or Sigma 150mm. Again both excelent lenses. Here the desision is what kind of subjets you are after. The 150 is better if you are interested in very small subjects (<2") The 100 is better if you are more interested in larger subjets (8-12") The range between either will work great. I am more into smaller subjects so I went with the 150.
I went with the 28/2.8 over of these better primes because I was over budget allready and had to cut something somwhere and this is my least used lens. I will probably end up getting the 24/1.4 before my next trip.
From what you say you use the Sigma 150m with an Ikelite but I don´t find it in the ikelite´s port list...What port do you use?
About the main topic, I´m thinking on getting a 5D with the sigma 15mm, canon 17-40, canon 100mm or sigma 150 (I didn´t know I could use it ) and I´d really like to be able to use the 24-70 but it (Ikelite) says is too wide (diameter talking...) 83.2mm by 80mm of the sigma 150mm. Has anyone tried the cheaper canon 24-85?.
What I haven´t been able to clear out is the right port/dome and diopter lens for the sigma 15mm and the 17-40...could someone be kind enough to put some light in my problems? since I have to order this material overseas is good to order the right things...
) and I´d really like to be able to use the 24-70 but it (Ikelite) says is too wide (diameter talking...) 83.2mm by 80mm of the sigma 150mm. Has anyone tried the cheaper canon 24-85?. 
since I have to order this material overseas is good to order the right things...
