I’m just about to purchase a Sigma 50mm f2.8 macro lens for my Canon 20D in an Ikelite housing, and I wanted to be sure I’m getting the proper flat port for it. Ikelite's Canon port chart says that the appropriate flat port for this lens is the 5505; that seems like it’s likely a typo, since the length of this lens is given as 2.6†on Sigma’s site, and the 5505 is for lenses under 4.5†long. It seems like the 5502 would be a better fit – Lenses less than 3.5†long. Am I missing something? Does the lens really extend nearly two inches when focused in? Does anyone have experience with this lens in an Ikelite port? (I've put in a question to Ikelite, of course, but I wanted to get this ordered as soon as possible, as I'm heading to Hawaii in a couple of weeks.)
And, of course, shout out if you've had bad experiences with this lens. I want a shorter macro lens for my rig (the Canon 100mm I have is fantastic, but definitely a specialty lens), and the Sigma seems to garner good reviews.
I can't say for sure how much it grows, but it does not need to grow 2 inches to not fit in the 5502 port. It only needs to grow 0.8" to not fit in the 5502 port. And I do not find it hard to believe that the lens would grow 1" when focused in to 1:1.
That said, it certainly would not be the first time there was an inaccuracy in Ikelite's port charts....Hopefully someone with the lens and both of those ports can chime in and give you a decisive answer.
But if you have not yet purchased the Sigma yet, you should consider the Canon 60mm. It costa $100 more, but it has much better auto focus, is more solidly built and does not grow when you focus and IMO is well worth the cost difference.
According to the Sigma Lens Chart the extended length of the 50 macro is 4"/101.5mm. I second the recommendation for the Canon 60 macro.
Thanks, Gudge, for the Sigma lens chart pointer. I hadn't found that. So the Sigma DOES extend an inch and a half when focused in. (It would probably fit in the 5502.41 - 4.1" - but only with no filters.) And thanks to both of you for the recommendations.
I'd thought of the Canon 60mm before, and don't mind the price difference; my main concerns with it were that it's EF-S (I'll eventually upgrade to a full-frame, though my U/W rig will likely remain EF-S for the time being, and I always have the 100mm) and that it's 10mm longer. My main problem with the 100mm is that if it's bigger than a softball, I have to be 10+ feet away to take a picture; I'm thoroughly dedicated to macro for the dive. Hmm, time to play with the difference between 50 and 60mm some more and see if it's really that big a deal...
