tele converters..a newbie Q

[Duinchlfc]

Hi guys..i just read about tele converters and found that its a much cheaper way to extend my zoom distance than get a fully dedicated zoom 400mm;600mm etc.So i would like to know if putting on tele converter would affect the F stops which i can use? And how much would one cost for a 30D? There's no indication of one available on the Canon accessories thread.Cheers for your help!

[FilterFunk]

a 1.4x convertor will make you lose 1 stop of light eg. F2.8 lens will become F4
a 2x convertor will make you lose 2 stops of light eg. F2.8 lens will become F5.6

fyi, unless your camera is a 1series, your camera will NOT af under F8 or under..

if you want original Canon TCs.. here are a small (but might not be accurate indication of the price)

Quote: EF 1.4X II Extender : (Yen52,000/US$285) RS$790 - CP $650 / TCW $570 / OP $495 EF 2X II Extender : (Yen52,000/US$290) RS$760 - CP $490 / TCW $560

3rd party TCs are much cheaper, optically similar except they do not have weather sealing and they are black in colour..

Quote: Kenko teleplus Pro300 1.4X - ($204 AP) ($245 TCW) ($240 MS) Kenko telelplus Pro300 2X - ($210 AP), ($205 Lords)

check out the 2 links below..
http://www.the-digital-picture.com/R...er-Review.aspx
http://www.the-digital-picture.com/R...er-Review.aspx

[moos blues]

Hi,

Are you talking about converters like the Canon EF 1.4x II and Canon EF 2.0x II

These converters mount behind the lens. these are not cheap and will affect the pic but are optimized for better pic quality, not all lenses can fit the converter. people advise using the 1.4x one.

yes they will affect the brightness of the image, the 1.4x reduces brightness by 1 f-stop , the 2x i think 2 stops ah. not sure.

i.e to say if u use a cheap zoom 300mm f5.6 u'll get F8 where ur camera will have issues auto focusing.


Screw-on type generally converters have very bad optics esp when u blow up the pics.

anyway problems like,
1. Not enough resolution, they dont resolve the image well enough.
2. They have CA, chromatic abbreviation i.e purple fringing on borders or light and dark.


how are the used are by screwing them infront of the lens. These converters come in different thread sizes and are more often used in pro-sumer cams.

If you really have to, i recomend glass converters and oly has (B) series for the Pro range. Olympus Tele Converter TCON-14B, it has a wide converter brother WCON-08B

[Duinchlfc]

but will there be any degrading of image quality?

[calebk]

Originally Posted by moos blues ... 2. They have CA, chromatic abbreviation i.e purple fringing on borders or light and dark. ...

It's Chromatic Aberration, not abbreviation. An aberration is a departure from a norm or standard. An abbreviation is a short form of a word.

Originally Posted by Duinchlfc but will there be any degrading of image quality?

Yes, moos blues has mentioned the TC affecting image. Please read through his/her writing slowly.

[Duinchlfc]

Okay thanks guys!

[adamadam]

Originally Posted by moos blues 2. They have CA, chromatic abbreviation i.e purple fringing on borders or light and dark.

I wanted to get CA status, but it meant that I needed to do extra units and that would extend my degree even longer, so I didn't.
Any Chartered Accountants here?

[miniUltraman]

Originally Posted by adamadam I wanted to get CA status, but it meant that I needed to do extra units and that would extend my degree even longer, so I didn't. Any Chartered Accountants here?

Get lost you... pple talking about Chromatic Aberration, you talk about Chartered Accountants *BISH*