kenko tubes not working?

I just got a set of kenko tubes today, finally..after they being on back order for almost 2 months.

The thing is they aren't working for me.

I attached the tubes to the camera then added the master lens I tried with my sigma 17-70 and canon nift fifty and everything is blurry...I can't focus in either auto or manual.

I took off the tubes, seperated the 12 mm and attached that alone, it was a bit better, but no where near I can get a decent shot..

Any idea what I'm doign wrong...I'm followign the instructions.

Turn off the AF, and get REALLY close to your subject. Use your zoom ring to focus, not the focus ring.

I love you!

The closeness is related to focal length of the lens setting and the length of the extension tube. With some of the really short focal lengths that are on APS-C cameras, sometimes it is impossible to get close enough...even with the object touching the lens surface is not close enough! Try setting the lens to 35mm or longer and try it with the 12mm tube. You can experiment with more tube length after that.

you just have to rock back and forth sometimes with macro. that's the challenge.

Broncobear, I would appreciate it enormously if you would post some pictures to show what you're getting with Kenko tubes and the 50mm lens, especially at maximum magnification

He might not have any ready for you, but here's a quick one I just did.

pretty much similar to my test shots...i deleted them but if you need any more from me..let me know!

braduardo wrote in post #2258653
He might not have any ready for you, but here's a quick one I just did.

Definately not a great shot, but maybe it will give you an idea of the magnification.

Thanks so much, Brad!

How many/which tubes are you using in this photo?

Broncobear wrote in post #2258964
pretty much similar to my test shots...i deleted them but if you need any more from me..let me know!

I'm definitely interested in seeing whatever you feel like sharing, particularly shots with the 50mm. I'll also be interested in hearing how you like the tubes as you get used to using them.

Patrick S wrote in post #2259178
Thanks so much, Brad!

How many/which tubes are you using in this photo?

That was the full stack (68mm) with the 50mm f1.8 which should be about 1.36 to 1 magnification.

I have more shots scattered around. Try checking my gallery under Macro. Some of the shots are with a regular macro lens, but most are just my 70-200 f4 L or my 50mm f1.8 with tubes.

braduardo wrote in post #2259254
That was the full stack (68mm) with the 50mm f1.8 which should be about 1.36 to 1 magnification.

I have more shots scattered around. Try checking my gallery under Macro. Some of the shots are with a regular macro lens, but most are just my 70-200 f4 L or my 50mm f1.8 with tubes.

I'll do that, Brad. Thanks again!

If you stack all three tubes with a wider angle lens you will not be able to focus because the plane of focus will be closer to the camera than the front lens element.

Depth of field is extremely limited for macro shots, so depending on the subject you are trying to shoot, much may appear to be out of focus because it is beyond the depth of field capablilties of the lens. Check your depth of field preview to see what you will get when the lens is stopped down.

The focus range of a lens is very limited when extension tubes are used. The easiest way to focus is to move the camera back and forth until you get reasonable focus and then only use the focus ring for fine adjustments. A zoom lens is easier to use because you can focus by turning the zoom ring. (Changing the focal length changes to focus distance with extension tubes attached.)

It is much more difficult to hand hold macro shots because the smallest camera movement makes big changes to the image. I try to use a tripod, remote release and mirror-lock-up whenever possible.

You need to get close up and personal with the tubes attached.

Patrick S wrote in post #2258597
Broncobear, I would appreciate it enormously if you would post some pictures to show what you're getting with Kenko tubes and the 50mm lens, especially at maximum magnification

I use this combo all the time, it works fantastic. Here is one of the first shots I ever got with it.