Pros and cons of upgrading from 40D to 7D or 5D for macro photography

What are the pros and cons of upgrading from 40D to 7D (again crop sensor) or 5D (Mark I or II, anyway - fullframe) especially for macro photography? I personally think that the 7D is the better choice (mainly cause of the crop factor and therefore the DOF), but many macrophotographers use FF cameras, what's the main reason?

For the 7D:

1) Increased usable ISO range, I think its one or two stops advantage over the 40D

2) Vastly improved AF control - if combined with a canon macro lens with USM focusing motors the 7D when set to ai-servo kicks in a new type of AF which counters the back and forth sway motion when handholding; making AF a more usable option in many cases.
Note I'm unsure if this feature works with 3rd party or not (I've no canon brand macro lens with af motor to test against the 3rd party lenses I own)

3) More MP resulting in more cropping capacity if needed

In general the jump for macro in the 40D to 7D is going to be noise and the AF; otherwise many of the advances of the 7D, many being totally in its AF performance over the 40D are not going to come to the fore in pure macro work (though of course if you're hunting dragons with a longer lens then the AF does come to the fore very fast).


The 5D your main advantage is going to be the wider angle of view that you get; useful for some larger insects. Note that this creates the illusion that the 5D isn't as magnified as the 7D (or any other crop sensor) if you compare shots at the same print size side by side; though the 5D has more than enough cropping capacity to solve the difference if so desired.
In addition the 5D can render a thinner depth of field if so desired (yes some people do use them wide open and not just stopped down).

Thank you. The main reason I would upgrade (but not soon) would be the MP. If I'm using the same system as now, I would be able to crop more, without getting too small resolution. Cause if I go for more magnification on the current system, it will result in shallower DOF.

The ISO - currently I'm using 100 or 200 if needed, so I guess this isn't a big advantage.

The AF - I don't use it at all, when shooting macro and scapes, and for other needs - I'm satisfied with the AF of the 40D.

If you are cropping a lot now you might well find that the 7D is the better since the 5D will give you that wider angle of view and thus force you to crop doubly as much on the original shot.

Myself I must say that whilst shooting further out and cropping does work, I far prefer to shoot close and get the shot to fill as much of the frame a possible; gives far more detail to the areas you record

Yes, it does, but it also makes the DOF shallower. Anyway, the next thing I'll by will be another Kenko extension ring (I already have the 20 and 36 mm). When I'm shooting jumping spiders I need to crop a lot, so I'll go for the ring (another 20 or 36 mm), because I can't get a 7D soon

You've already stated your requirements, which BTW, all macro shooters face...you want a wide DOF which means more distance to target, more MP on target for cropping ability because you're further away.
Focus stacking works great for static subjects but, for moving spiders, it's a real PITA. My DsIII doesn't do bad, but when the 40 MP DsIV come out, I'm upgrading.

I wouldn't spend the money upgrading from a 40d to a 7d just for macro, if you want the faster FPS then sure, my 7d does not do noise well at all compared to my 500d.

60D is worth considering too as the swivel LCD is very useful for low level tripod work.