Canon 600D after taking shots the viewfinder is sometimes dark....

[jpod]

Hi

I use a Canon 600D for clinical macro photography - dental. Just recently when I take a picture the optical viewfinder is then darker and it is hard to see to take the next pic.

I turn on and off - I take the lens off - I am not sure what makes it resolve but then it works again for a bit and I can see clearly through the viewfinder - it is bright again.

No idea what I am talking about but does the following mean that my lens is faulty - it is a Sigma 105mm macro lens. Used with a Canon ring flash.

I wonder if the lens aperture blades are sticking? Can it be repaired? It is a very old lens but in good condition (20 years old?).

Thanks in advance pod

 

[jpod]

Hey thanks fellas that is really helpful indeed. It is darker but otherwise a normal view. I can't recall of all the viewfinder info is visible - I will make a note next time.

When I took the lens of the aperture was stopped down.

Looked up CLA - clean lubricate and adjust. I have no complaint with the Sigma lens it has been used for ~2 decades.

I don't have access to another lens - a great idea and I will make enquiry's.

Thanks for the link that is very kind.

Cheers pod