Bobbit Worm

Hi Folks,

I finally finished processing most of my photos from the Philippines trip I made w/ the other WP mods Matt S, Drew W., and Herb K.

Here's a photo of a bobbit worm taken in Anilao:

This photo was taken w/ the Tamron 70-200mm at 200mm

Cheers

James

Nice shot, James! What a friggin creepy critter that is!

Glad you're finally going to start sharing some of those 70-200 shots with us! I've been waiting with baited breath (or is that just bait breath?)!

This photo looks very sharp at the focal point, albeit with limited depth of field (or rather, with foreground sand in focus rather than the back of the beastie). That is NOT meant as criticism, but rather just trying to dig into the effectiveness of the 70-200...what was your aperture?

One of the things I was wondering is whether the 70-200 at 200 would give more depth of field than some of the long fixed focal length macro lenses (e.g., Sigma 150, Canon 100 with TC or wet diopter, etc.). Based on your results from this trip, do you have an opinion on that yet?

Hi Bruce,

Thanks. I am really liking the Tamron. It's like taking a 50 and a 100mm on the same dive.

The photo was taken at F16 @ 1/160th at 200mm at the MFD for the lens+500D which is about 14" from the lens tip.

The DOF of a photo ONLY depends on a few things - the F-stop, the subject distance, and the focal length. Since the f-stop is also related to the focal length of the lens, it really only comes down to the f-stop and subject distance.

So it doesn't really matter what lens you use - the DOF just depends on the distance really. So if you need more DOF just back up, turn your strobes up, and then crop out some of that massive 22 megapixel file :-)

Cheers

James

...So if you need more DOF just back up, turn your strobes up, and then crop out some of that massive 22 megapixel file :-)

I just attended Marty Snyderman's seminar at Scuba Show in Long Beach, and one of his main points is that you should always GET CLOSER to reduce the amount of water between you and the subject!

Now I'm REALLY confused!

Bruce, that is true.

But also remember that the closer you get - with a fixed focal length lens - the less DOF you get.

Cheers

James

Post deleted because I realized it was irrelevant.

What James is saying is that macro DOF is determined only by f-stop and magnification. Reducing magnification increases DOF so backing away from the subject does just as James says. If you don't want to back away (or can't) then you'll need a shorter focal length and that's where the zoom comes in handy.

Using a zoom macro allows you to choose your subject distance while maintaining your perspective. That flexibility is very handy as many times conditions dictate what your subject distance is.

Congratulations, James, it's hideous!

That little mysis shrimp doesn't stand a chance ;-)

What impresses me is that I think that the lens has rendered the background very nicely blurred. One of the most challenging things of shooting on sand it avoiding a distracting background. With some lenses, even when out of focus the background blur is not smooth and is very distracting. On this one it provides a nice smooth background to complement the subject.

Just for info, James. How much is this one cropped? I suspect that is not the natural aspect ratio of your camera!

Alex

Good catch Alex! :-) If it complements the subject, I regularly crop to 8x10 or 4x3 aspect ratios. I cropped this one to 8x10 and pulled it up from the bottom a bit to minimize the OOF area. I'd say it's about a 75% crop.

Yes, the bokeh is much better than the Sigma 150mm. The sigma makes weird background artifacts when shooting on sand and pebbles.

Cheers

James