Camera lenses

[Tracey]

I currently own an Olympus E410 DSLR, and have two lenses, the standard 17-45mm and a 45-150mm (both Olympus)

I've heard that I can use the old SLR lenses on a DSLR if you buy an adapter ring.

What are the advantages/disadvantages of using an older lens?

Many thanks
Tracey

[4call]

Old lenses tend to be cheap for quality of the piece of glass that you're getting but there's a reason for that... you'll have to inspect it very closely for wear & tear. Also it's unlikely to be able to use the autofocus features of your new camera (which, unlike old cameras, don't tend to have the nice split screen focusing aids in the viewfinder)... & you'll have to set the f-stop manually as well... the results can be remarkable but it certainly makes you work for the end product... which is no bad thing in some photography but a pain in high pressure instantaneous situations.

... just my 2p 

[Tracey]

Thanks for you reply.
I presumed I would need to manually focus, but I never thought about the split-screen, I guess I need to think deeply about this.

One other thing that crossed my mind about the old lenses is the focal length (is that the right word for it, its been YEARS since I did photography in a big way) So say I wanted a longer zoom than the 40-150 I have now, what would I need to look for in the older lenses?

Many thanks
Tracey

[4call]

Right...  for a start the image sensor on your camera is much smaller than the 35mm size that people think about when talking about lens length... it's actually 18mm wide on the Olympus, so... close to 2x multiplying factor... so what you see through a 150mm lens it would take close on a 300mm lens to replicate on a 35mm...  well, that's half the story 'cos actually it's a crop factor & your sensor is only seeing the centre 18mm of a much larger 35mm image (assuming you're using a lens that was made for full frame 35mm). What this does mean is, on a full frame lens, you'll be seeing the best bit of the image (lenses tend to go off the further from the centre you look)... which is a good thing 

There is a wiki article about it here...

http://en.wikipedia.org/wiki/Four_Thirds_System

... & a nice graphical explanation here 

[Tracey]

Thanks again for your reply, lots of reading to do there.

No doubt I'll be back for more information/asking more questions when I have confused myself