Cheap telephoto lenses

[owenter]

I was impressed with the response I got on here for another question so decided to push my luck and ask another, this one really comes from a friend. No, really!

There are quite a few cheap telephoto lenses for sale on Ebay. It seems you can get a 500mm lens for about 90 quid + postage. You also get to choose from a conventional long type and the mirror lens I remember from the 70/80's.

So my "Friend's" question: Are these any good? I guess they work as claimed but what about image quality etc.. Is it worth a punt for 100 quid?

[chris-p]

It's a matter of opinion. Personally, I don't think they're worth it.

The catadioptric (mirror or reflex) lenses might be worth a punt for the very long ones if you're prepared to put the effort in (and I love the effects they give) but the standard "long" ones are going to be pretty nasty.

I've seen horror stories about people buying them and they've knackered the camera body. But ultimately, for £100 for a 1000mm lens (which will be a 500mm with a 2x teleconverter) you're not going to be getting very good materials. The glass will be poor quality, the AF (if they do AF) is going to be rubbish, the build quality will be terrible etc.

I suppose it depends if you can afford to loose £100 if they're rubbish. If you can then perhaps it's worth a go. Personally, I don't have £100 (poor student you see) so they're not worth it to me...

[KeithT]

I think glass is the real asset and investment in photography. If you buy good glass from the outset it will not only serve you well for a lifetime, but will probably be with you for life too, unless you change camera manufacturers. Camera bodies change every year as more and more gimmics are added to entice the enthusiast away from their money. You can put good lenses on new and old bodies if the mount fits and still get great images. Sadly, the other way around isn't true.

[cosmicma]

you don't mention what camera you want the lens for
the only mirror lens that comes to mind thats any good was made by minolta and will go on the sony alpha bodies
how much you can pick one up for i have no idea

the cheap ones you see on ebay are exactly that i think it's the same lens with whatever mount to suite the make of body you have and are poor at best

[JeffCohen]

don't even think about it ,i just sold all my cheapie lenses and invested in canon L glass ,the difference is startling .its been said many times before ,the camera is only as good as the lens

[flake]

There were some quite nice mirror lenses around way back when they were popular. The advantages were that they were compact and lightweight for their focal length, and uncomplicated too. The drawbacks were the slow maximum aperture (usually f/8) which cannot be adjusted, no autofocus, and a rather strange donut effect, which some like, and others don't.

When buying one remember that there are different ways of construction so make sure you do some research as to how good they are before buying. Canon & Nikon both offered reflex lenses so I don't think it's reasonable to suggest that only Minolta/Sony are 'any good'. There were also offerings by Sigma Tamron & Tokina, I found these sites which you might find useful:

http://www.mirrorlenses.co.uk/ml_lenses.php
http://www.photozone.de/mirror-lenses

If it comes to a choice between a long lens and nothing then almost anything is better than nothing, but remember that lenses such as the Sigma 50 - 500mm can be bought second user for not much more money than some of the better mirrors, so be very choosy and do all the homework before you part with your money.

I do have a question for Jeff though, although I have quite a few L lenses there is no way I can justify the cost of the longer ones, which I don't use very often anyway. I've had the 400mm f/2.8 on the camera, but it costs £6300 the 500mm f/4 £5K the 600mm f/4 £7K. You can't seriously be suggesting that someone considering buying a lens for £250 - £300 should instead be considering one of these?

[chris-p]

Originally Posted by JeffCohen

don't even think about it ,i just sold all my cheapie lenses and invested in canon L glass ,the difference is startling .its been said many times before ,the camera is only as good as the lens

I think thats a step (or two) further up from the 1000mm for £75 kit the OP is talking about!