Macro Photography with Canon 550D EOS - Correct Size of Tubes?

Minch · Feb 18, 2013

Hi there,

I would like some advice on the best way to get into macro photography. I have a couple of questions, perhaps someone could be kind enough to help me out.

Basically, I have a Canon EOS 550 camera and a while ago I bought the Sigma 105mm DG Macro lens. I wanted to take some cool insect pictures but I had so much trouble with the DOF that I got tired of taking pics of insects' noses in sharp focus with the rest of them in a blurry mist behind them. I kind of gave up after a while. But I am going to Thailand in a few weeks and it could be a great opportunity to get some pics of nice insects and start to re-use my equipment, so I going to try and solve my issue and educate myself in the technical aspects of the mighty macro.

From research, I figured the DOF issue was due to poor lighting and the aperture, so I will get hold of a proper flash instead of the standard one and I think this will solve the issue. My second question is that I think my lens is 1:1 and - in order to take the kinds of pictures where you can see the nose hairs bristling on a fly - I think I need to get hold of an extension tube. Either this or crop down, but nonetheless - I want to get up close.

I know this decreases available light, so that's why I will get a better flash, but which tubes should I get? I have heard that Kenko is a good make and have researched around a few forums for the buzz, but I can't find anywhere the correct size of tube that I would need to fit between my Canon camera and the Sigma lens? They can't all be the same, surely?

Can someone recommend me a good extension tube to search for, or even better a decent one on amazon with a link so I can order the right one? All the shops here ( Switzerland ) so so massively overpriced that I think it's a better deal for me to order something online than use a local shop.

Thanks for your help, would be great to get some advice on my little macro problem

Matthew

cgipson1 · Feb 18, 2013

I don't shoot Canon... but I believe these are the right tubes Amazon.com: Kenko DG Auto Extension Tube Set for the Canon EOS AF Mount.: Camera & Photo. The Kenkos are basically the best tubes you can buy.. the cheaper knock offs are often not reliable, and the really cheap ones lack the electrical contacts and mechanical coupling.

For Macro, your DOF is minimal... as you found out. I usually shoot between F16 and F22.... and yes, I use flash. I highly recommend a diffuser for the flash also... other wise you get really ugly glare. Try this one, I have had good luck with it: Amazon.com: Fotodiox 6"x8" Softbox for Nikon, Canon, Vivita, Sunpack, Nissin,Sigma, Sony, Pentax, Olympus, Panasonica Lumix Flash: Electronics

I also recommend the Raynox DCR-250... it actually does an excellent job of almost doubling magnification. Amazon.com: Raynox DCR-250 Super Macro Snap-On Lens: Electronics

You are welcome to check out the Macro set on my Flickr to see some of the results you can get with these combos. Ask further questions if needed...

jaomul · Feb 18, 2013

Kenko tubes come in a set of 3. each are different lengths and allow closer or farhter focussing depending on which you use. You can also combine lengths by adding tubes together

Overread · Feb 18, 2013

A few thoughts to add to what has been said.

Extension tubes work by reducing the minimum focusing distance of the lens and thus increasing the magnification. They also strip a lenses longer distance focusing limiting you to a few feet down to maybe only a few inches in front of the lens (it varies from lens to lens and with the amount of extension you add).

The rough maths for extension tubes is:

(length of extension tubes in mm - divided by - focal length of the lens) + magnification of the lens = magnification :1

for example your 105mm macro lens with its focusing set to the closest distance (ie magnification at 1) and 50mm of extension tubes would give you:

(50/105)+1 = 1.48:1

As you can see, for a given length of extension tube, you get more magnification gain with them on shorter focal length lenses. There is, of course, a limit as to how much extension tube length you can add; on the one side the more you add the more difficult the setup becomes to hold and use; on the other the minimum and maximum focusing points can, with enough length added for the focal length of the lens, move inside the lens itself (ergo it becomes impossible to focus the lens).

2) Close up lens attachments/macro filters/diopters/ these are all the same thing (The first name is their correct name, others are those used in advertising or common chat) and work similar to extension tubes save that the magnification gain for a specific attachment increases with longer focal length lenses.
There are also two general grades of these, cheap kinds which are typically a poor quality single element lens; and a higher quality coated multi element setup. The former work but will do so poorly and earn this line of accessories a bad name in general (many people buy the cheap ones because they are cheap). The latter are often very high grade and can deliver fantastic results, they might be adding glass to the setup but often as not (esp if you're shooting with smaller apertures such as f8 or smaller) you can't see the optical difference very easily if at all on most shots.
The power of these elements is shown by their diopter number, the higher the number the greater the degree of magnification gain you can get.

In general I would say that at 100mm you are at the half way point between where you want extension tubes or close up lens attachments. My personal preference is close up lens attachments as they are quick and easy to add to and remove from a setup and they don't add much bulk to the assembly. Raynox make a very good range of these, their DCR 150 and DCR 250 are very popular starting options (I would suggest the 250 as it is the stronger); whilst they also have their MSN 202 and MSN 505 which are much higher powered yet again. They also have some other options and a few discontinued lines on the market - all of which are high grade optics. Canon also produces their own in the 500D and the stronger 250D - again good quality optics well worth considering.

For the future you might also want to consider the Canon MPE 65mm macro lens - the only lens on the market that goes from 1:1 through to 5:1 magnification with no additional items added. It, however can't focus any further than its 1:1 distance so it is restricted to macro work only. It is expensive, but it is an option to consider for the future if you really like shooting high magnification macro photography - note that the MPE is not "the best" there are other options that get you to high magnifications which can deliver superior optical quality; there are cheaper and expensive alternative options to this lens - each with their own ups and downs.

Austin Greene · Feb 19, 2013

I have paired the following tubes and flash with my 50mm f/1.8 and have gotten some pretty great results.

Tubes: Amazon.com: Fotodiox Canon EOS Macro Extension Tube Set Kit for Extreme Close-up: Camera & Photo
Flash: Amazon.com: Yongnuo YN-565EX ETTL Speedlite Flash for Canon: Camera & Photo

IMO, there is no practical reason to pump out the extra money for electronic extension tubes, unless you are wanting to focus stack easily. Just use the well known "DOF Preview" trick to set your aperture to where your lens is sharpest, and then go from there.

Toga

P.S: If you want to see some of the shots I've taken with this setup, check out my website in the sig.

TCampbell · Feb 19, 2013

There is no "glass" in an extension tube. So optically, it doesn't matter. The tubes have electrical contacts to pass-through the communication between body and lens.

They do decrease the amount of light (so the focal ratio is no longer accurate, but if using the internal camera meter rather than an incident meter the camera meters after the light makes it into the body so it should self-correct.)

Not _all_ lenses can be used with extension tubes. Canon's mark "II" version of the lenses were designed to also accommodate EF-S lenses (the original tubes didn't support EF-S lenses). I believe Kenko also updated their tubes to work with EF-S lenses. But since an extension tube alters the back-focus distance on the lens, some lenses can't have their back-focus distances altered too much and still work. For example... Canon's EF 14mm f/2.8 wide-angle lens reportedly cannot be used with an extension tube (I'm not sure why someone would actually *want* to use an ultra-wide angle lens on an extension tube... but o.k.)

I've read some reviews which claim the fit & finish is better on the Canon and that some Kenko tubes have a little "play" in them if a heavy lens is mounted to it. With that said, the Kenko tubes still seem to be much more common (probably because of the price tag.)

Overread · Feb 19, 2013

I've known some to say that Kenko tubes are identical to Canon ones in almost all respects. I think that Kenko does produce a lower quality (no contacts) version of their tubes which might have confused some of the market when commenting on them.

When it comes to the "no glass" part of the argument that is both true and not true. Yes it is true that there is no glass to affect the light in an extension tube, but on the flipside you're shifting the lens from its designed ideal focusing point. This does result in a very minor degradation of image quality, the kind you are unlikely to ever see in actual processed photos on display unless you were to push to extremes (ie adding a vast amount of extension and shooting wide open - indeed shooting closed down as many do with macro often hides many optical weaknesses).

togalive - the aperture stopping down trick works, but only for Canon (Nikon and other brands have to use either different options or don't have the choice to). However its a pain to use. First its slower to setup, then you also lack the ability to change your settings on the fly as you shoot, you have to stop and dismantle everything. In addition it increases the light loss so focusing is that much harder as the viewfinder image becomes much darker (esp when you're closing down to f8-f16). One might be able to counter this by using live-view of course, though that introduces its own problems*

* Camera holding with liveview is not as stable since you're holding the camera away from your body to view the screen - unless you can rest the camera on something stable and firm or use a tripod.

Austin Greene · Feb 20, 2013

Overread said:
togalive - the aperture stopping down trick works, but only for Canon (Nikon and other brands have to use either different options or don't have the choice to). However its a pain to use. First its slower to setup, then you also lack the ability to change your settings on the fly as you shoot, you have to stop and dismantle everything. In addition it increases the light loss so focusing is that much harder as the viewfinder image becomes much darker (esp when you're closing down to f8-f16). One might be able to counter this by using live-view of course, though that introduces its own problems*

Just going to on to say things from my own personal experience, which has been quite a bit over the past months with this setup. You are correct in saying that it takes more time to set up and change, but functionally that argument is a bit null. Your DOF differences are so minimal with 49mm of tubes on a 50mm that changing from even f/1.8 to f/8 only buys you a couple millimeters. I'm a pixel peeper in every sense of the word, and yet I have never shot outside of f/8 (with this setup), because f/8 is where the 50mm is sharpest. Plus, changing to a larger or smaller aperture would only buy me 1-2mm at most, hardly something to be too concerned about.

Second, I have never shot any of my macro shots through Live View, simply because I haven't had to. Even when doing night-time macro shooting, I can still see enough of my subjects to determine when I have a sharp focus on their relatively tiny eyes. If anything, live view shooting for me is more difficult.

I'm not saying a 50mm + tubes is a replacement for a quality macro lens. That said, I have been fortunate enough in my experience with it to get photos equal to or beyond many of those I've seen with a variety of legitimate macro lenses, and I know I'm not alone.

Bottom line, IMO, is that tubes (even the non-electronic version) are as viable an option as any setup, if you are willing to learn how to use them, just like you would with any other setup.

TCampbell · Feb 21, 2013

Overread said:
When it comes to the "no glass" part of the argument that is both true and not true. Yes it is true that there is no glass to affect the light in an extension tube, but on the flipside you're shifting the lens from its designed ideal focusing point. This does result in a very minor degradation of image quality, the kind you are unlikely to ever see in actual processed photos on display unless you were to push to extremes (ie adding a vast amount of extension and shooting wide open - indeed shooting closed down as many do with macro often hides many optical weaknesses).

That's why they caution that not just "any" lens can be used with an extension tube. A lens technically is optimized for a specific back-focus distance. When you use an extension tube, you're changing that distance to something which the lens was not optimized to use. You can still focus until you get the best image, but under scrutiny it's usually not as good as if the lens were at it's proper distance.

This is why a "true" dedicated macro lens will always give you the best performance (but also costs the most.)

scorpion_tyr · Feb 22, 2013

You can save a bunch of money by getting manual focus extension tubes. I have autofocus, but I find most of the time when I pair them up with my 100mm f/2.8L Macro I'm so close that I'm manually focusing anyways. If your main problem is getting just part of the insect in focus then your problem isn't needing extension tubes, you're shooting with too large of an aperture. When I'm doing macro work I'm usually shooting at f/16-32. And for that, yes I usually do need an external flash, and it needs to be off camera.