MP-E 65mm vs EF 180mm Macro Lenses

Nope, it only goes from 1x to 5x. So you'll have to get the 180 and use some tubes or something to get more than 1x when you need it.

1x is indeed the largest field of view (smallest magnification) with the MP-E 65. Working distances with this lens are very short. I'm not sure that a 180 is the best choice for studio work for magnifications of 0.25-1x though - you will probably find the working distances a little long at the lower magnifications. The upside of this is that you don't have to spend as much on lenses to get the coverage you need. The downside of the MP-E 65 is that you may need a rather more expensive lighting set-up - the MR 24 EX macro flash is not a cheap item.

What about the 100mm macro? It's cheaper than the 180 and by all accounts an incredible lens. Like its L cousin it can focus from infinity to 1x, and I've never heard any complaints about it.

You should very seriously consider the 100 mm f2.8 macro lens. It is not too expensive and gets from infinity to 1:1 easily with decent working distance. Secondly, you can use it with a 1.4x extender and extension tubes to go to at least 2:1 with not too much trouble. Then, if you want, you can use another technique, stacking lenses, to get to greater reproduction ratios still, but I do not think you will need to. Check Mark Plonsky's explanations here on photo.net. He explains how to use stacked lenses to get incredible macro results.

I think you can get off much more cheaply than the MP65 or the 180 macro and still get dynamite results!

Jeremy, where are Mark Plonsky's explanations?

I hate to say this, but I think you need BOTH the MP-E 65 and a 'regular' macro lens -- as others have said, the 100/2.8 is probably your best bet. I have extensive experience with the latter and have borrowed the MP-E 65 with Canon ringflash a few times.

The '65 has a minimum magnification of 1:1. You'll need something else to get out to 1:3. However, no other Canon macro lens will get you close to a full-frame image of a 3 mm insect. You can jury-rig the 100 (or the 180, or the 50) with extension tube and teleconverters to get to higher magnifications but it's a clumsy process, compared to the effortless way the '65 goes out to 5X.

However, the downside of the '65 is that working distances are extremely small, so it's almost essential to get the Canon ringlite (MR14), which is expensive and makes odd 'broken doughnut' reflections on shiny surfaces (see example images below) or the even more expensive MT24 twin light unit. What either of these might do in terms of generating reflections off of a glass photo tank, I shudder to think.

Here's a couple of pictures of a jumping spider made with the MP-65 and ringflash. The animal was about 1 cm long and the front of the flash was probably about 25 mm from the spider's face:

The first image is at about 1.3:1 and the other is at about 3:1. As you can see the lens is very sharp but (as is inevitable at these magnifications) there's not much DOF (I think I was shooting at about f16 -- if you stop down much more than that, diffraction will start to kill resolution).

Thanks for all the advice. :) I'm beginning to worry that Mark may be right--maybe I do need both. One possibility I've been looking into is getting one of the regular macros like the 180 or 100 and using bellows to take me up to 5:1 when necessary. (Actually, about 7:1 would probably be ideal for my smallest critters... so what I really want out of my full system is a range from 7:1 up to 1:3.)

Does anyone have experience using bellows with these Canon lenses, and recommendations regarding that idea? What's the formula for the magnification I can get with bellows?

If I remember correctly, the magnification with bellows or extension tubes is roughly equal to:

extension/focal length

Thus, to get to 1:1 with a 100 mm lens, you need 100 mm of extension (this doesn't account for whatever optical tricks occur with an internally focused lens). So to get to 7:1 with a 100 mm lens, you'd need about 700 mm of extension -- more than two feet of bellows or tubes (don't even think about what you'd need with a 180 mm lens!). Not a very practical idea. That's why many dedicated bellows-usage macro lenses have very short focal lengths.

Also, the 100 or 180 mm macros are optically designed for magnifications around 1:1, and may not work very well at much higher reproduction ratios. I'd guess you could manage up to maybe 2:1 or 2.5:1 with a 100 or 180 mm lens with combinations of extension tubes and teleconverters, but beyond that would be very awkward and possibly (probably) not very good optically. That much magnification will change the effective f stop as well, by roughly the same factor as the magnification. At very high magnifications, diffraction will rear its ugly head even if you use the lens wide open, let alone stopped down. Let's see... if you did manage to get to 7:1 with a 100 mm f2.8 lens, the effective aperture with the lens wide open would be roughly about f18 or so.

I think at least one other responder mentioned using stacked lenses (typically a short focal length lens mounted reversed in front of a longer focal length lens). I've never tried that but have heard that it works (although the same diffraction issues and optical problems would crop up, especially at higher magnifications).

Unless your insects are very, very shy, skip the excellent but very expen$ive 180 and get the 100 mm for your low- magnification images. Or check out the excellent macros from Sigma, Tamron, etc.

I only have the 100/2.8 and with 68mm of extension tubes I can get just past 1:2. On my 300D I can get 11mm to fill the width of the frame. HTH.