Tele converters

HOOVER29

Member
Joined
26 Mar 2009
Messages
387
I’ve noticed that these are fairly cheap compared to lenses.
What are the pros & cons of using a tele converter as they sound so easy to use, just simply screwed to the end of your lens.
Should I buy one or start saving for a bigger lens?

Carl
 
Sponsor Post - registered members do not see these adverts; click here to register, or click here to log in
R

RailUK Forums

70014IronDuke

Established Member
Joined
13 Jun 2015
Messages
2,781
This is from the days of yore, when even 400 ASA colour film was a novelty - but I bought a 2x converter and used to use it with a 135mm f 2.8 Soligor (and, I think a 180 mm f 3.5), but only for a short time. The results were crap. Cheap, but nasty, I'd say.
 

eastwestdivide

Established Member
Joined
17 Aug 2009
Messages
1,875
This is from the days of yore, when even 400 ASA colour film was a novelty - but I bought a 2x converter and used to use it with a 135mm f 2.8 Soligor (and, I think a 180 mm f 3.5), but only for a short time. The results were crap. Cheap, but nasty, I'd say.
Almost identical experience in the early 1980s, with a 2x converter and a 135mm Tamron lens. The effective f-stop was 2x worse, and the quality towards the edges was iffy to say the least.
This attached between the lens and the camera body.
I dare say that a more expensive converter would give better results, but then you're getting towards the territory of a new lens anyway. Plus once you get beyond about 300-400mm focal length, hand-holding becomes tricky to say the least.
With the quality of lenses and sensors now, you might as well use max zoom and then crop the part of the photo that you want.
 

HOOVER29

Member
Joined
26 Mar 2009
Messages
387
So save the pennies for a bigger lens.
I’ve been doing research on the internet on them.
Apparently they alter the amount of light into the camera.
Coming from a bridge camera there is so much to learn. Hopefully not financially.
 

70014IronDuke

Established Member
Joined
13 Jun 2015
Messages
2,781
So save the pennies for a bigger lens.
I’ve been doing research on the internet on them.
Apparently they alter the amount of light into the camera.
Coming from a bridge camera there is so much to learn. Hopefully not financially.
They don't "alter the amount of light coming into the camera" - it's just plain physics. You have a prime lens of a certain f stop, and once you put a 2 x on, you have the same amount of light actually going into the lens, but are 'zooming in' on what there is, so you have to open up two stops. (To get the same amount of light from the subject matter, you would have to add two stops to the prime lens - that's why long lenses with wide apertures are awfully big in diameter, heavy, and expensive.)

But actually, as Taunton - OOPS, sorry EAstWestDivide - raised the matter - I found using a converter was actually WORSE than 2 stops "loss" - more like three stops, as it must have absorbed some of the light.

OF course, it's also true what he says - once you go above a focal length of even 200mm, it's almost impossible to hold the camera steady enough by hand alone - you really need to use a minimum of 1/250 second. Best to use a bean bag, monopod or tripod.
 

Nighthawke

Member
Joined
7 Nov 2015
Messages
57
Any additional glass is likely to degrade your photos. Unless you are using say a Canon converter with L-glass then I personally wouldn't bother.
 

Top