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welshboy
29th of October 2010 (Fri), 04:36
Hi' can anyone help me out. What is the difference between a Zoom and a telephoto lens,Thanks for your help.Mark

h14nha
29th of October 2010 (Fri), 04:44
Do you mean a zoom and a telephoto zoom ? If so, its sort of generally considered 300-400mm and above are the telephoto lens.

JeffreyG
29th of October 2010 (Fri), 04:46
A zoom lens is a lens that can change focal lenghts.

A telephoto lens is a lens with a focal length longer than the normal for the camera format.

There are zoom telephoto lenses, but also zoom wide angle lenses.

FlyingPhotog
29th of October 2010 (Fri), 04:46
Hi' can anyone help me out. What is the difference between a Zoom and a telephoto lens,Thanks for your help.Mark

A "Zoom" lens is able to change its focal length within a given range. 17-40mm, 24-70mm, 70-200mm, etc.

"Telephoto" lenses are generally focal lengths longer than the accepted standard focal length of 50mm. They can be zooms or "prime" lenses which are fixed-focal lengths.
85mm, 135mm, 200mm, 300mm, etc.

Hope this helps...

rusty.jg
29th of October 2010 (Fri), 04:49
A "zoom" lens is typically any lens where you can adjust the focal length - e.g. 10-22mm, 17-40mm, 70-200mm, etc. This is opposed to a "prime" where there is only one focal length - e.g. 60mm, 100mm, etc

A telephoto is a lens where the focal length is fairly high - it can be either a "zoom" type or a prime. I'm not 100% sure on the exact numbers but the following about right:
< 35 - wide angle
35-100 - mid-range
>100 telephoto

Of course there are many overlaps and you can have a lens that can cover one or maybe more areas - e.g. the 24-105 covers wide through to short telephoto.

EDIT:WOW, didnt realise there would be so many replies in the time I was writing this.

welshboy
29th of October 2010 (Fri), 05:35
Thanks alot' for your help and time for your reply to help me out.Mark

muusers
29th of October 2010 (Fri), 05:44
This makes me think of several zoo visits. Whilst taking my 50D and a 300 F4 IS,

"Whoow, you must see the moon with that... howmuch zoom is that?"

- non

"What do you mean 'non'?"

- It cant zoom...

"Oh ok..."


:D

rusty.jg
29th of October 2010 (Fri), 05:52
This makes me think of several zoo visits. Whilst taking my 50D and a 300 F4 IS,

"Whoow, you must see the moon with that... howmuch zoom is that?"

- non

"What do you mean 'non'?"

- It cant zoom...

"Oh ok..."


:D

Indeed. Just makes you realise how much marketing cr*p manufacturers put out that has very little meaning - e.g. "10x zoom" doesnt really communicate any useful information. Along with the megapixel war.... </rant>

SkipD
29th of October 2010 (Fri), 08:19
A telephoto is a lens where the focal length is fairly high - it can be either a "zoom" type or a prime. I'm not 100% sure on the exact numbers but the following about right:
< 35 - wide angle
35-100 - mid-range
>100 telephotoThe definitions applied to focal lengths really depend on the camera format (size of the film frame or digital sensor) that the lens is attached to. What's mentioned in the quote above is approximately proper for a camera using the 35mm film format (24mm by 36mm). For that format, 50mm is the accepted "normal" focal length.

Canon's marketing is misleading now that they sell several format cameras that can use the same EOS family lenses. All of their definitions for "wide angle", etc., are based on the 35mm film format. In fact, though, a 35mm lens used on an APS-C format camera such as a 50D are longer than the "normal" focal length for that format (which is roughly 30mm). Canon still markets the EF 35mm lenses as "wide-angle" with no reference to the format.


Canon also has some VERY misleading information in their lens marketing information. Here are two quotes right off their web site:
From the "Wide-angle" EOS lens group: By expanding the apparent distance between the foreground and background, they provide a unique perspective.
From the "Telephoto" EOS lens group: The longer focal lengths effectively compress the distance between the subject and camera to capture the details and the feeling of a far-off scene.Both of these statements are giving the reader the false impression that focal length affects perspective. This is totally wrong. If you don't understand the truth, please read our "sticky" tutorial titled Perspective Control in Images - Focal Length or Distance? (http://photography-on-the.net/forum/showthread.php?t=672913). The "sticky" thread can be found at the top of the General Photography Talk forum.

Wilt
29th of October 2010 (Fri), 12:19
Everybody uses the term improperly to mean "Longer than a 'normal' lens", but 'telephoto' is actual an optical design in which the distance from the 'rear node' of the lens to the focal plane is SHORTER than its actual FL. For example, a lens with 500mm FL should normally be a physicially long lens to provide 19" from rear node to focal plane; with large format cameras these are often referred to as 'long focus lenses'. But a 'telephoto' design has a much shorter distance to focal plane, so that less distance needs to be provided to the focal plane and the lens can be physically shorter.

Similarly, 'wide angle' lenses are typically 'retrofocus' design with a longer-than-normal distance from focal plane, so that there is no interference between the back of the lens and the reflex mirror in the dSLR which has to flip and down for exposure.

Zooms can be 'retrofocus' or 'telephoto', or even be able to shift their designs from one to the other as they are zoomed from 'wide angle' to 'tele' focal lengths