Question for Dalantech or any of the other Macro Masters

[Bonish Photo]

I've been fooling around alot with my tubes and have a few questions for anyone who knows more than I do ( Basically Everyone )

I'm not sure if it's the combination of the tubes or the fact that I'm putting them on bigger zooms - 70-200L f/2.8 is what I normally use.

Here is the question. Dalantech, in your shots you have the entire subject in focus with the background blurred to add DOF. On my shots I've been trying to get, I have such a limited DOF, I can get the head of the insect in focus, but the focus drops off so fast, that even a few centimeters behind the eyes or nose is blurred and out of focus.

How do I fix this problem? Most of the images are lighted properly, and exposed correctly except for the DOF. I guess if I was trying to just focus on a very small section, I'd be accomplishing that, but I want to get more in focus, but still be able to be in the macro mode.

I've been reading through your website, but I only have the set of Kenko tubes and have tried to swap them in different orders to experiment? Does this make a difference? I also heard that some photographers will put a 2x extender on the lens to acheive a differnt focus point? Could you explain this any better or link me to a spot on your site that might explain it more in depth.

Thanks for any answers you might be able to offer. For those looking to experiment with Macro, make sure to Bookmark Dalantech's site!

[Southern Wolf]

I will see if I can help a bit.... I have no where near his expertise... but I can prob point you in the right direction.

as for the DOF... you need to stop down your lens. What is you fstop... if its around f/4 or whatever... you need to go up to around the highest your lens will go to.... mine is around f/32

This will increase your DOF dramatically.

as for the order to attach tubes and tele converters.

Attach the tubes directly to your lens... this allows you to focus closer... then put the tele between the tubes and body. This allows you to magnify the image that you were able to focus closer on due to the tubes.

Hope that makes since.

[bob_r]

as for the order to attach tubes and tele converters.

Attach the tubes directly to your lens... this allows you to focus closer... then put the tele between the tubes and body. This allows you to magnify the image that you were able to focus closer on due to the tubes.

Hope that makes since.

Pat,

Attaching the teleconverter between the body and the tubes also allows using teleconverters with lenses that aren't supposed to work with them. Some lenses can not work with TC's because the optics collide when trying to mate them. With the tubes attach to the lens, there are no optics for the TC to collide with so they'll work (just don't expect to focus to infinity).

For extending the DOF, I suggest you read Dalantech's tutorial about using a flash and shutter priority. This allows your camera to select the corresponding aperture setting and it will normally be wide enough to give pretty good DOF, especially if you set your ISO up a little.

Bob R

[Dalantech]

I'm not sure if it's the combination of the tubes or the fact that I'm putting them on bigger zooms - 70-200L f/2.8 is what I normally use.

Here is the question. Dalantech, in your shots you have the entire subject in focus with the background blurred to add DOF. On my shots I've been trying to get, I have such a limited DOF, I can get the head of the insect in focus, but the focus drops off so fast, that even a few centimeters behind the eyes or nose is blurred and out of focus.

How do I fix this problem? Most of the images are lighted properly, and exposed correctly except for the DOF. I guess if I was trying to just focus on a very small section, I'd be accomplishing that, but I want to get more in focus, but still be able to be in the macro mode.

DOF is completely aperture and magnification dependant. If you're not getting enough depth for the lighting conditions then you'll have to increase the ISO to get a larger Fstop or use a flash and manual mode with the Fstop at 11 (that's the Fstop I use most often).

I've been reading through your website, but I only have the set of Kenko tubes and have tried to swap them in different orders to experiment? Does this make a difference?

No -it's just an air gap. The more you add the more distance you place between the lens and the sensor and the light that the lens projects onto the sensor spreads out -and that's why the magnification increases. The total combined distance of the tubes makes a difference, but not the order that you put them in.

I also heard that some photographers will put a 2x extender on the lens to acheive a differnt focus point? Could you explain this any better or link me to a spot on your site that might explain it more in depth.

It depends on the lens. If you have a lens that's designed to use a teleconverter, like your 70-200 F2.8 L, then you can add a 1.4x teleconverter between the lens and the camera and it will give you a 98-280mm F4 (you lose one stop) or you can add a 2x teleconverter and you'll have a 140-400mm F5.6 (you lose two stops). You'll also get an increase in magnification, but I'm not sure how much. Adding an extension tube along with the TC will increase the magnification even more.

The problem with using a zoom telephoto for macro is that it's not possible to design one that's sharp at minimum focus and infinity -lens designers have to choose where to put the best performance, and since it's a zoom telephoto they figure that you'll be shooting distant subjects with it. So you may be doing everything right and sill get soft images because you're using the lens at a distance that it wasn't designed for. One way around that limitation is to use a 500D Closeup filter. Your working distance will drop to 18", but the lens will be sharp like its focused at infinity.

The best answer I can give you is to ge a dedicated macro lens. All of them are excellent -so pick a focal length and a brand. My recommendation for someone just starting out is any macro lens in the 100mm to 150mm range (a 150mm if you find yourself chasing skittish critters in the heat of the day).

For those looking to experiment with Macro, make sure to Bookmark Dalantech's site!

Thanks for the props

[Bonish Photo]

Thanks for all the great answers everyone!

Looks like I'm back out to experiment.

Sorry I havent been posting anything lately. Between work, family and trying new things with the tubes, I'm getting frustrated with my images and havent felt any of them were worthy to be seen

[Southern Wolf]

They are always worthy... even if it is just for learning purposes.

By seeing the images...we may be able to direct you in a simple change that will make all the difference in the world.

[gdietzman]

Pat,

Here is one other idea for you.

One of the techniques I use is to find some angle that puts the background a bit further away from the subject and then crank down the f-stop for greater DOF. For instance, if I find a bug on a stalk of grass I may move the camera's position to move the background further away--moving the background even a foot or two makes a big difference. Then you can crank up the f-stop to get greater DOF to get the entire bug in focus and still retain those nice soft backgrounds that help isolate the subject. Of course, that requires a certain set of conditions that aren't always available.