Macro 50 or 100 with 1.6 factor?

[bmccall]

Hi,
I'm moving to the Canon digital world from Minolta (due to their lack of support for DSLRs). I had the Minolta 100 Macro and enjoyed that focal length. My question is which macro do you feel is best with the 1.6 factor of the 10D? The 50 lens would be just under 100 at 80, and the 100 would be the equivalant of 160. I kind of feel that 160 may be a bit too much for general macro. Am I wrong here?
Thanks,
Brad

[picaman]

Check out the specs for each of them here:
http://www.usa.canon.com/eflenses/

My choice would be the 100 f2.8. Offers greater magnification and longer working distance...good if you want to add lighting to subject plus it has USM as well as an optional tripod mount ring

[oldlincoln]

Hi Brad,
The 100mm is a fine lens and gives a nice working distance. The main difference from your old lens will be be perspective (more foreshortened). I don't think that USM makes much difference here. With the really long macro helixes on these lenses, your focusing choices are slow and really slow. I don't find autofocus very useful for macro anyway, so it doesn't bug me much. The 50mm is less expensive, but it only goes 1:2. If you need 1:1 out of the 50, the life size converter is needed. Then, the price and size are a wash with the 100, but you lose infinity focusing.
If you are really flush, the Telephoto MP-E 65mm f/2.8 1-5x Manual Focus is a pretty exciting prospect with its "holy cow!" magnification range, plus at 1.6 crop, its perspective will be pretty close to your old 100mm Minolta.
Regards

[Roger_Cavanagh]

Brad,

Don't be confused into thinking that the infamous 1.6 factor will affect the optical performance of a lens: it does not. The sensor in the 10D, like the D30 and D60 before, is smaller than standard 35mm film, therefore, you get a reduced field of view not greater magnification.

Some people like to think that because they can fill the frame with a smaller subject they are getting a free lunch with 60% greater focal length. Personally, I think this is complete tosh, but some argue that it is an advantage of cameras like the 10D.

Notwithstanding that, macro performance is measured in terms of magnfication with respect to life size. This is not affected one jot by the smaller sensor. Of course, the largest object you can fit in the frame at 1x will be smaller with the 10D than with a 35mm SLR.

Regards,

[bmccall]

Thanks for all the replies - I hadn't thought about the 1:2 of the 50. 1:1 was one of the reasons I went with the Minolta 100 in the first place, so that makes the Canon 100 more what I am looking for.
I have been a bit confused with the 1.6 factor - I've seen it related to a crop factor and a magnification one.
So, if I understand correctly, the 1.6 factor doesn't make objects appear 1.6 times closer (magnified), the crop factor gives you the field of view as if they were.
So a 100mm lens is not a true 160mm lens optically.
thx,
Brad

[Roger_Cavanagh]

bmccall wrote:
I have been a bit confused with the 1.6 factor - I've seen it related to a crop factor and a magnification one.
So, if I understand correctly, the 1.6 factor doesn't make objects appear 1.6 times closer (magnified), the crop factor gives you the field of view as if they were.
So a 100mm lens is not a true 160mm lens optically.
thx,
Brad

Brad,

That's correct.


Regards,

[bmccall]

Thanks for the facts!!
Brad