16-35 versus 17-40 Canon zoom

I'm doing some pool testing testing with both 16-35 and 17-40 Canon zooms in preparation for a shoot next week. Both are nearly the same size and should accept the same zoom gears. The Seacam gear for the 16-35 fits the 17-40 no problem. Minimum focus is the same too. In researching other issues about the lenses I found:

http://www.luminous-landscape.com/reviews/...non-17-40.shtml

Among the comparison images is a shot of a streetlamp from the corner of the frame, zoomed wide on both lenses. Here the 17-40 is significantly better. As corner resolution is an area of concern for any wide angle zoom behind a dome port, starting with one that performs better topside is no doubt an advantage when choosing what to use underwater.

More later as I do some real world testing.

Steve

"Performs better" isn't exactly right. It's sharper in the corners when zoomed all the way out at f4, but it does vignette a bit more. According to the luminous landscapes review, the 16-35 is a full stop faster and is sharper, and "better" when zoomed in at the same f-stops.

I shoot ambient light indoors a lot, so the 16-35 is definitely a "better" overall lens for me.

Eric - My reference to "performs better" was only in the context of corner resolution. I did a pool test yesterday with the 17-40 with Seacam PVL 25, 30, 35, 40, 45, 50 and 55 in combination with wide port, fisheye port, and superdome. Today I'll look at the jpegs critically to see which port and extension combination is best.

Again, I am specifically looking for optimal performance in the corners at the wide end, as any/all of the combinations were sharp in the center and fine zoomed to 40mm end.

I agree with the LL conclusion that if I owned at 16-35 I would not buy a 17-40. The advantages of wider maximum aperture and other benefits you describe are significant. But, as I have neither, I'm quite eager to see what ports work best for the 17-40.

Steve

Howdy, Steve! What camera will you be using these lenses in?

Hi Jim - Happy Thanksgiving to you and Deborah.

Camera is EOS1Ds

Housing is Seacam

and the pool test results suggest that:

1. Don't use wide port at all unless maybe it works with a diopter. All tests performed without diopter. It did not vignette even at 17mm, but optical perfomance was poor.

2. The 9" Superdome is best for sure. The PVL35mm extension worked best at the 17mm end of the zoom range. The PVL40 was maybe a little better at the 40mm end of the range. But since I'd be using it mostly wide, the superdome + PVL35 is probably optimal.

3. The fisheye port was acceptable for times when you need a smaller port with open water critters like sharks or dolphins, or when you need a small port to poke though a window on a shark cage. The fisheye port worked best with the PVL35 at 17mm and the PVL 40 at the 40mm end of the range. But if I had to have the image sharp corner-to-corner, a superdome is the better option.

These are pretty subjective impressions and there were variables. Nothing was on a tripod for example. I was just trying to dial in the optical ballpark before leaving for the Bay Islands on Monday.

I'll probably play with the 16-35 in the pool before I go as well, but it is hard to replicate the "dimensional" resolution required of a port and lens combination without real world experimentation.

Steve

Thanks for the info! Let me know what you find with regard to the 16-35. I need to do some tests with the 20mm lens, as the recommended WP combination is a little soft. I am guessing switching to the superdome will make things better...

Thanks, Steve. It looks like you're mostly using digital these days. Good shooting in the Bay Islands!

It looks like you're mostly using digital these days. 

Yes, and no. I had a shoot for an ad agency last week and their final project was going to be heavily manipulated in Photoshop. So, I figured they'd want to start with digital capture. And they did, but in the end felt they could get better results with scanned film, so I was glad I gave them both.

So long as clients still want film I'm happy to shoot it. I still love holding that wet roll of E-6 up to the light to see if the shot is there. But, inevitably. the commerce of photography will be almost exclusively digital by this time next year. At least in my studio.

Steve

Thanks again, Steve. We're dragging Ken Nemeth to Fiji tonight, and I've been trying to proselytize him to digital. He's still holding out with his F100. You've had a huge influence on him, so I think he'll be going digital pretty soon.

It's interesting to read some real-world feedback with the 17-40L underwater.

To my mind, it's going to be a very popular choice for underwater photography with Canon DLSRs.

I use mine on a 10D with the 1.6 FOV crop, so my situation is slightly different with regards to vignetting and optical performance in the corners.

Topside, optical performance is excellent. I'd only buy the 16-35L if I needed f/2.8 for available light. (would be nice, but the cost difference makes this an expensive luxury).

The initial buzz on the 17-40L lens was that it was soft. You don't here that opinion much any more.

I did post a couple of brief lens test comparisons with the 20mm and 24mm primes on photo.net when this lens was first released. My opinion was that optical performance was as good as the primes, which suprised me. I haven't compared it to the 16-35L, but based on the comparison's I've seen (including the LL one), I think the differences in optical performance are subtle.

After a week of use with the 17-40 I'm pretty well pleased. It is sharp for sure, but the vignetting is an issue, especially wide open. When you shoot at 45 degrees to a primary subject, with the reef being closer in the foreground, the corners will be soft. This happens topside as well as underwater so it appears to be a lens issue rather than a port issue. However, when everything is along a single plane, it will be sharp in the corners.

I notice Photoshop CS has an action to correct vignetting common with some popular zoom lenses. I'll give that a try as I dig into the new files recently captured.

I meant to travel with both 16-35 and 17-40 to do some side-by-side testing, but forgot to pack the 16-35, so that test will have to await another opportunity. I do think it is a good value in a useful zoom range.

Steve

Stephen Frink asked me to post a few of his shots taken w/ the Canon 1Ds and the 17-40L lens:

I'll let Stephen fill in the details about the shots.

Cheers

James

Thanks James.

Bottom line is the 17-40L seems plenty sharp, and worked fine with both superdome and pvl35, and fisheyeport and pvl35. By the end of the week I was using the fisheye port a bit more just because it handles easier, but I'd still give the nod to the superdome for better corner resolution. The dolphin shots are with superdome, while sharks and diver are with fisheye port, but same port extension in each shot. Probably around F-8 on average.

Steve

Those are awesome images. It makes me want to get a 1Ds and seacam to put my 17-40L onto/into. That's not an expensive setup, right?

My 17-40L used through the flat port of my crappy EWA-Marine plastic bag hasn't produced results like that yet, strangely enough. I'm about to spend a solid week at Ningaloo Reef shooting with that lens, so i'll be interested to see how it goes.

Seeing those pictures (fish/diver shot on bottom especially) reminds me how nice it would be to be shooting with a full frame DSLR. The 1st dolphin shot is also brilliant, IMHO.

Here's some more tests done on the 16-35 versus 17-40 that might be of interest.

http://www.stephenfrink.com/seacam/canoncorners.shtml

Steve

Thanks for the informative comparison, Steve!

I'm wondering if you have tried fixing camera position and setting both lenses to have the same field of view (zooming the 16-35 in to 17mm, and shooting the 17-40 wide open?). Also, it would be great to get some comparisons at a variety of focal lengths.

I'm wondering if you have tried fixing camera position and setting both lenses to have the same field of view (zooming the 16-35 in to 17mm, and shooting the 17-40 wide open?).  Also, it would be great to get some comparisons at a variety of focal lengths.

Sorry Eric ... this was more subjective test than empirical science. But yes, it would have been good to check the 16-35 at 17mm in a direct comparison. The lenses were loaned to me by Canon and have now been returned, so unfortunately I can't take the tests any further.

How'd your shoot go in Indonesia? Stellar no doubt.

Steve