Earlier this year, I tried my Canon 100mm macro lens with a Kenko 2X TC, and because my 1D series camera can AF with that combo, I really liked it. I therefore special-ordered a manual focus ring for it from Seacam. While I was at it, I thought I'd order a manual focus ring for my Sigma 150mm and the 2X TC (which I knew would NOT auto-focus).

Well, I just had a chance to use both combos with the manual focus rings I got from Seacam on my recent Indonesia trip, and I have several things to report:

- Canon 100mm with Kenko 2X TC is a great combo, at least with my 1Ds Mk II camera. It can be auto-focused to get in the "neighborhood" of focus for a given subject (I have my camera's custom function set with AF programmed to the * button), and then use the MF ring to fine-tune focus. Many of the photos in my gallery from this Indonesia trip that show a 100mm lens in the EXIF info were actually taken with this combo (EXIF should show 200mm, but for some reason doesn't).

- Sigma 150mm with Kenko 2X TC was a bust. For some reason, it is impossible to turn the MF knob with this combo, so my focus (on the one and only dive I used it) was "fixed" for the entire dive. And because it was an effective focal length of 300mm, it was REALLY difficult to move the camera towards and then away from the subject until it was actually in focus. In fact, the only thing I really got clear photos of was a winged pipefish, and I could only get part of its head in focus at a time (see below). My best guess is that the Sigma lens with the TC is so heavy that the focus ring rubs on the side of the port, making it impossible to turn the ring. I therefore consider this particular focus ring virtually worthless, and likely won't use it ever again.

Cool, a macro panorama! Have you tried Photostitch on those two?

Mike

I think a lot of people don't realise how hard very long lenses are to aim underwater, until they hae tried them!

Alex

Alex is right. In the case of the 150mm, it is already hard enough to use, even without the TC. If there's even a little bit of surge, getting sharp focus where you want it is really hard...

Yes, I agree with you and Alex. I've used the 150mm by itself successfully, and with the 500D diopter (although I now think I prefer the Canon 100mm with 2X TC to the Sigma 150mm), but it definitely works best with no surge. I figured that under the right conditions (no surge, stationary subjects), such as at Lembeh, using the 150mm with 2X TC would be doable (focusable manually). I still think it would work...as long as the lens can be manually focused. As the close-up shots of the pipefish show, you can get some really cool detail on tiny subjects that way. The problem really was that, without use of the manual focus ring (as described in my original post), the only way to focus was to physically move closer or farther from the subject, and that was a REAL PITA, something I'm not willing to do again.

Bruce - I'd love to see what the problem might be, and share it with Harald for his input. No one wants you to have a focus gear you can't use, for whatever reason. In a best case scenario Seacam will make it work for you, or if it can't be resolved we'll take the gear back and refund your money. I realize you haven't asked for any resolution from us, and in fact I only know about the issue because I read it here. But, we are eager to make it right for you. We can't give you back your photo-ops from your last trip, but hopefully we can make it functional for your next trip. It was a special order gear never fabricated before, and it may well be as you suspect that gravity makes the long lens (and gear) sag against the interior of the macro port.

That's very gracious of you, Stephen. I knew when I ordered the gear that it was a custom "one off" part, and I assumed that I was taking full risk, which is why I didn't return it or expect you to do anything when it didn't work.

OTOH, if you/Harald can learn anything from it that helps others (or even me) in the future, that would be great, and I really appreciate your offer to "make it right," which I consider above and beyond what you are obligated to do. I'll forward the gear back to you, and await word on whether there's a solution or not!

Great service Stephen

What Steve said :-)

Long macro lenses like the 150mm+TC, 180mm, 70-180 (Nikkor) and 200mm (Nikkor) need some kind of support underneath them. Alternatively, if the focus gear/knob is on the front of the port, then you can sometimes use that to help support the lens tip.

I'll reckon that Bruce was using the focus driven from the housing, requiring a really long focus gear. When it gets that long, the gear can deform when you turn the focus knob on the housing.

James

Bruce - James makes a good point. Was it a long focus gear, or one designed to use with the Systemport? http://www.seacam.com/en/produkte/ports.htm Having a short gear driven by the focus knob on the Systemport might be the solution. I haven't seen your gear, so will be eager to have a look.

Mine is NOT the Systemport. The gear Harald made for me was simply a really long cylinder (like the regular focus gear for the 100mm and 150mm lenses, only LONGER). I can understand how the Systemport (with a much shorter focus ring) might work better...

More Sigma 150mm experience here. I used this lens + 500D as my sole macro lens for my last two dive trips. Now that I have a Seacam MkII housing, I have a really good * button control, so I used CFn 4-3 for all my macro focusing. I was surprised that the lens would AF in almost all situations and I hardly had to use the MF knob at all.

I just picked up a Tamron 1.4x TC and it seems to work very well with the Sigma 150mm. It brings the lens to F4 @ 210mm. The AF seems to still be working pretty well. At close focus, and with the diopter mounted, the field of view (FF) is 32mm across.

Cheers
James

For what I see, this combo it´s been getting more fans every day... but I wonder, what´s the benefit of this combo over the, let´s say Nikkor 105mm+6T (or even a 500D) besides the obvious working distance, I mean, magnification stays the same or really close with both.

So one combo would not give you the chance to get more tiny stuff, just more shy stuff than the other... Am I wrong?

Well hmm. When you eventually go back to using a full frame camera (:-) you will find that the 105 isn't a "super macro" lens anymore, it's just a normal macro and fish portrait lens. That's what happened to me, and when I switched to the 150mm.

The 150mm +500D on a FF camera behaves like a 105mm on a DX camera. The close focusing distance is still a good 6-8 inches or so from the port tip which is a realistic distance for macro photography underwater.

Cheers
James

I'd rather use a 150mm + 1.4x converter than a 100mm + 2x. The lens will be faster, will AF better, and the images will be somewhat better. It will not focus as close or achieve as much ultimate magnification but there are diopters for that.

If you value shooting the 100mm straight up, then I think it's hard to justify traveling with the 150mm. I consider the 150mm nothing more than a better 100mm + 1.4x converter permanently attached.

Having tried the 100 + 2x and a 200mm on a DX sensor, I agree with others here that it is really tough to use that 300mm effective focal length. It doesn't surprise me that the 150mm + 2x was hard to manage, but I think the 1.4x converter would be a different story. You'd have to get that manual focus solution working, though.

I didn't know Seacam was offering the Systemport for Canon.

I tried the 105mm with a 2x TC and stacked diopters. I finally just started laughing underwater. What was I thinking? Getting one good shot becomes a challenge. I've also got the 200mm, which I don't use much.

Hello,

I'm using a Nikon D70s + Nikkor 105 + Kenko TC2x + 12mm Kenko ring. I can and I use autofocus with this setup.

You have to be calm with the autofocus. When it works its great. This setup allows me to aproach some animal live such as the one on the photo attached.

f/5.6 at 1/350 dual Ys-110 on i-TTL: