Canon 40d Help please

Messages
44
Name
kevin
Edit My Images
Yes
Hi, can anyone explain what i'm looking for when i want a lens for the above 40d? i ask because although i bought a "EF" 75-300mm lens it works up until you take the photo then comes back with error messge on screen.

As i am new to this i have no idea what to look for apart from "Canon Ef" dslr compatible now i have a lens which i must sell

please can anyone explain :thumbs:
 
If that is a Canon "EF" 74-300mm, then it should work with the 40D.

As far as I know, some older 3rd party lenses from Sigma, Tamron etc with a EF mount may not work with a modern digital camera but I believe older Canon lenses should.
 
Is it happening with this lens only? try cleaning the contacts. A little acohol such as ethanol or a eraser on a pencil is supposed to be a good method too. It might just be dirty contacts causing the problem.
 
All Canon EF and EF-S compatible lenses should work.

What is the error message you are receiving?
Does it appear when you switch to a different lens?
Do you know wnyone else with a Canon camera that could try it?

It could be as simple as dirt on the electrical contacts between the lens and the body. Without knowing what the exact error message is, it's going to be impossible to provide much useful information.
 
As already said, some older 3rd party lenses will not work properly with newer DSLRs. Sigma provide a chipping service to update the firmware but I've no idea of cost.

Any Canon EF or EF-S lens should work properly irrespective of age.
 
Its a Sigma tried cleaning contacts but the camera works fine with other lenses ! i can take a photo the lens does focus but after pushing the shutter releace it comes up error on the screen, i cannot do anything with camera then unless i switch off then back on and the same thing happens, i have tried other canon lenses but they work fine

thanks at least im getting some information which helps
 
Sigma did provide a "rechipping" service but not sure if they will still carry this out for your lens.
You will note that most ebay sellers of older sigma lenses will say whether or not the lens is compatible with modern digital cameras....if they do not, ask the question.
Best option is to sell the lens (making it clear that it does not work with digital) and get one that does.
 
Last edited:
Still might be worth contacting a Sigma agent and seeing if it can be rechipped at a reasonable cost.
 
Kevin hi,
The Canon interface is a closely guarded secret and how the body talks to the lens is not information that is shared with 3rd party lens manufacturers, for this reason they sometimes dont work with a Canon body e.g. if Sigma bring out a lens today it will in all probability work with every Canon body (that takes ef/ef-s lenses) to date but may not work with a body brought out say next year, perhaps a 5Dmk3 for instance. This is known as reverse engineering, for that reason you need to be very careful when buying 3rd party lens, Sigma in particular have a reputation for not working sometimes.
Personally I would not buy a Sigma lens second hand, nor probably new as I couldnt (and nor could they) guarantee it will work with what I now have or what I might buy in the future, however some people are happy to buy Sigma and take the risk. Your choice, I tend to buy Canon either new or second hand as I am confident they will work.
Additionally some recent Canon lenses "talk" to the Canon flashguns, not sure if Sigma etc do this either. Micro adjustment is available on some Canon bodies (50D onwards), I havent checked if 3rd party lenses do this either, or to be fair if older 2nd hand Canon ones do.

Matt
 
but after pushing the shutter releace it comes up error on the screen,

What is the error number you are getting?

It's likely that this is due to the lens not being chipped for later digital models. If you contact Sigma with the lens serial number they should be able to confirm if this is the case and whether or not they can rechip it for you (and at what cost).

I suspect it will be cheaper to get a new or second-hand Sigma 70-300 APO.
 
Back
Top