[Jon L]

I just received the ProOptic Macro extension tubes (13, 21, 31mm) which is supposed have electrical communication with the body. Trying it out today, I found only the 13mm tube useful for my 35mm lens, and even then I'm VERY close to the object.

21mm tube on my 85mm lens (1.6x crop body) worked OK, but I pretty much realized auto-focus really wasn't going to be used and that any amount of wind makes it impossible to get a real sharp shots. 

Depth of Field is tricky, and I could use some advice on what F/stop to use and in what mode (used aperture priority mostly), etc.  Also, with the extension tube attached, the 85mm lens really was useless as a general-purpose lens, as I couldn't get it to auto-focus on anything far, really.  Is *this* normal?  Some samples.







 

 

[Photon46]

All your discoveries and conundrums are what I'd expect given my experiences with close up photography with various formats. While I've done far more close up work with view cameras than small format, the limitations of lenses and extensions apply across formats. When you're working with a lens extended beyond it's normal working range, it's tricky to find the optimum working range for close up work. Depth of field is very shallow and the longer the lens, the shallower the depth of field. Working with aperture priority is the correct mode. A rock solid camera support is a necessity as well. Working in the field using macro mode is also tough, wind is a real problem. Studio light allows control in much greater degrees. As you noted, you're not going to focus on anything other than close up objects in a narrow depth of field with an extension tube mounted, this is normal. All in all, I've found extension tubes to be useful for an introduction to close up macro work. Most who develop an interest in macro work end up purchasing dedicated macro lenses. If nothing else, it saves the hassles of opening up your body with every lens change and exposing your sensor to dust. Small apertures greatly exacerbate the appearance of dust spots on your sensor as you'll find.

[Jon L]

All in all, I've found extension tubes to be useful for an introduction to close up macro work. Most who develop an interest in macro work end up purchasing dedicated macro lenses.

What would be the advantage of a dedicated macro lens over extension tubes?  Is it mainly more DOF?  I don't plan on doing whole lot of macro work, and I've heard people say they prefer the image quality of their expensive Canon L lens + extension tube over "reasonably-priced" macro lenses, which is why I went that route. 

[thunderbrick]

Macro lenses are the descendants of "process" lenses of the pre-digital printing trade, where edge-to-edge sharpness is paramount.  A 50mm 3.5 macros is typically better corrected for close distances than, say, a 50mm 1.4, which is optimized for distance and low light.  I've seen some 50mm 1.4 lenses that had TERRIBLE edge-to-edge sharpness or even bent parallel lines close up, and while reducing the aperture setting  will help improve it, it's still not great.

DOF is determined by focal length, distance from subject, and aperture setting, so a 50mm macro and 50mm non-macro lens at 5 inches away at f11 will have the same DOF.    The macro will have a better edge-to-edge sharpness on flat items than the non-macro.

In many cases, throwing buckets full of money at a lens may reduce the historical differences between macro and non-macro lenses. I LOVE using big telephotos (300 and up) on extension tubes.  Really cool perspective, and it's a helluva lot better way to photograph the entrance to a hornet's nest.   

[Photon46]

Unfortunately, physics dictate that depth of field stays the same at a given aperture/focal length whether one uses lenses or extension tubes. So the macro lens gives you no advantage over extension tubes in that regard. I have read in various places that macro lenses have a flatter field of view compared to extension tubes. You would be quite right that a high quality normal lens with an extension tube will yield better images than a mediocre macro. The main disadvantage to the use of extension tubes in my mind is the inconvenience of switching lenses and the introduction of dust into the body when switching lenses. My photography work for print has to be absolutely free of dust spots and I do not like changing lenses unless I have to. Every time I open up the camera to change lenses, dust is getting in, especially outside the studio environment. I get REAL tired of spending $60 on wet swap sensor cleaning kits and the hour and a half it takes to clean the sensor on my Canon EOS 1Ds II. Plus, there's always some risk you could damage the sensor and trash the camera. Sure, you can "dust bust" with Photoshop's healing brush, but eventually you find that you're spending too much time retouching and you have clean the sensor.

[Photon46]

Thunderbrick is right about the macro being a descendant of flat field process lenses. I actually still use a huge copy camera at times at work on occasion. It took me a good while to learn to use it, very difficult to find the exact magnification ratio and size image you want at first. When you're using a camera that holds a 26"x 38" piece of film (or larger on a copy board set up behind the camera back) and your extension rail is ten feet long, there's a lot of potential adjustments to make as you switch between 240mm, 500mm, and 760mm lenses. It's a pain to use, but sometimes a big piece of film will give you things you just can't get with even the best digital imaging and scanning available.

[Jon L]

I've seen some 50mm 1.4 lenses that had TERRIBLE edge-to-edge sharpness or even bent parallel lines close up

Hmm.  Interesting, you are talking about 50 F1.4 without extension tube but used at its closest focusing distance? 

I just shot some Macros with Canon 50 F1.4 on 31mm extension tube.  This one's at F/16 1/32 sec hand-held.



Some others with 85L on 31mm extension tube. 





I must say my arms are much less tired after working with 50 F1.4 compared to the humongous 85L, but I can shoot macro from farther away with 85mm.  I've been reading up on this whole macro business, and I must refrain from getting crazy things like Canon MP-E 65mm f/2.8 1-5x Macro lens or uber-expensive L macro lens.  The whole point of getting extension tubes was to add some macro capability to my already-overspent lens arsenal for only $75. 

However, if there are some less-expensive good manual focus macro lens that will mount on canon body (via adapter) that will give me aperture control, I may look into that on FleaBay.  Any suggestions?

[Jon L]

Canon 35mm F/1.4L with 13mm extension tube.  A few inches of space to work with between lens and subject.

[thunderbrick]

Hmm.  Interesting, you are talking about 50 F1.4 without extension tube but used at its closest focusing distance? 

It was a Minolta Rokkor on tubes.  An older lens to be sure, but it was gawd-awful at close ups.  Is there a Canon adapter to take FD lenses to EOS mount?  They had a pretty good 55mm (50?) 3.5 macro lens years back.  I bought one on a Canon FLb camera on fleecebay for $16, just for the halibut.

If you could find a nice flat-field enlarging lens of 4" or more with a focusing mount and Leica or Schneider threads, it should be easy to adapt.  Enlarging lenses I would kill for 20 years ago are going dirt cheap now.   

If you shoot Nikon you can use any Nikon-mount bellows set made in the last 50 years.  Some of them even offer view-camera-like focus control.  Maybe the PB-5 or PB-6?  I forget which one I have in the basement.  Clumsy, but you could put literally thousands of inexpensive lenses on it.

[Jon L]

I had the 35L on when I found some bees.  With 11mm extension tube, this meant I was only 2 inches away from the bee in order to focus!



 

[Jon L]

85mm lens with 31mm extension tube, hand-held without flash at dusk.  I'm finding out I love the effect of dusk lighting and extension tubes on textures.  The petals look like cloth in photo, but they didn't look like that to the naked eye at the time.

[Jon L]

A couple more with extension tubes, this time with Canon 24-70L lens.  While I always wish I had a tripod at the time, all hand-held shots, and I do wonder how people manage to carry around tripods for macro shots 


IMG_9847 by drjlo1, on Flickr



IMG_9849 by drjlo1, on Flickr