Canon Life-Size Converter EF

My local dealer has just loaned me a used Canon Life-Size Converter EF to try out as I have a 50 macro Canon Lens (they are thin on the ground in the UK and this is the first I've actually seen used!). However, although I've not actually shot anything with it as yet, my first impression is that it is actually a close-focus optimised converter - it looks as though it probably increases focal length AND it will also fit the 100mm macro and the 60 EFS (with 12 mm of extension in between) - in all cases AF becomes a bit dodgy on my 1DS but it certainly allows for much smaller images to fill the frame (up to about 2x life size I'd estimate).

Has anyone experimented with this converter, and on any lenses other than the 50? Any comments or advice?

Hi Paul,

You are correct, it's not just a teleconverter. It also changes the maximum focal distance when used w/ the 50mm lens.

I haven't tried it w/ any other lenses - will be interested to hear how it works w/ the 100mm

Cheers

James

Hi James

Interesting. I've trawled the net and the general concensus I've come up with is that it is a 1.4x teleconverter - and it seems to be optimised for macro use. I've just shot a few images to try it (very roughly I'm afraid) and my first impressions are as follow:

With the 50 macro it certainly delivers good1:4 to 1:1 images (quarter to life size).

With the 100mm (usm) it delivers good something to 2:1 (not sure of the max focus but minimum is twice life size on sensor - and I am using a full-frame camera) images.

With the 60mm EFS and 12mm of extension it delivers adequate images, but my first impressions are that they aren't up to the 100mm results.

It most certainly works with all lenses and achieves AF with 50 and 100 at maximum manification (I purposely used it indoors, on a tripod with poor available light to focus with) but struggles with the 60.

Looks like this could be a useful little item - I'll continue testing.

Interesting! If it does deliver 2:1 on the 100mm then it's better than a 1.4x. Any sense of change in focal length? Try focusing to 1:1 with the 100mm with and without the convert and note the distances between lens and subject.

Hi Herb

I will do more testing but I' have just checked and the closest focus subject size available on the 100 usm macro with the life size converter (LSC) is ~20~22mm across the full frame (a 1DS so ~36mm frame) which gives an actual magnification of a little less than twice life size. However putting this LSC on changes the physical size of the entire lens system by a fair bit so whilst I do have to back off the camera to achieve 1:1 I don't think that this actually says much other than the focal length certainly has changed and increased substantially. I can measure it but my optical knowledge, whilst not brilliant, suggests that this will not give any really meaningful info; it will merely confirm an increased effective focal length.

I need to do some really careful checking, but my gut reaction is that the image quality was still pretty high at maximum magnification with the 100 and LSC. I figure that this could be a useful little set-up both above and below - I'll test above for now as the salty stuff looks too much like mud here at the moment!

That still gives a magnification of ~1.7x. Very good.

Actual focal length at macro focus is complicated. In practice, it's really the working distance, front of the lens to subject, that's of most interest.

While you're testing, please check the minimum magnification also i.e. what's the biggest subject that will focus.

Thanks for checking this out.

I second that - thanks Paul. I too am interested to hear what the working distance is with the 100 + LSC (front of lens to subject) at maximum magnification.

Cheers

James

James/Herb

Working distance for the 100 + LSE at minimum focus is about 150mm/6" from the front of the lens.

I have tried the Lifesize converter with the 50mm Compact macro on a film camera for underwater macro work.

The combo produces extremely sharp images - colours and contrast are very good. I noticed no visible degradation in image quality when comparing result taken with and without converter.

However focussing does get very dodgy - the lens is constantly hunting for focus.

This is not generally noticed above water (I found), but becomes a problem underwater.

And, you lose the infinity focus with the LS converter, but you knew that :-)

More info: the LSE adds just under 35mm to the length of lenses its attached to so it will require an extender of 35mm added to any port.

James/Herb

 

Working distance for the 100 + LSE at minimum focus is about 150mm/6" from the front of the lens.

That's the same working distance for the 100mm lens by itself. So at least at that range it behaves like a 1.7x teleconverter. Thanks Paul.