2x lens converter

[mike11165]

Do lens converters sacrifice the quality of the lens/shots? seems like a cheap way to enhance your lens, but is it effective or just beginner trash equipment?

 

[table1349]

Do lens converters sacrifice the quality of the lens/shots?

Yes, they will always affect the quality of your shots.

seems like a cheap way to enhance your lens, but is it effective or just beginner trash equipment?

Depending on the converter and the lens that you use it on it can either be trash or very effective. A $50.00 converter is not going to be well engineered or made of high quality materials. If however you are willing to spend some serious money for a top line Canon, Nikon, Sigma, Kenko or other lens makers for a converter that is suitable for your equipment you can get some pleasing results. If you use it on the type of lenses that converters are designed for and If you are using it on good (write in expensive most of the times) glass you can get very acceptable results.

Converters are a compromise. With a 1.4X converter you loose one f-stop. With a 2X converter you loose 2 f-stops. Converters are really not designed to work on short focal length lenses. The basic minimum is a lens that is no shorter than 100mm. They tend to work better on primes than zooms. Zooms in general are softer than primes; be it a tad in a high quality zoom or quite a bit in your general consumer grade zoom.

A converter is going to magnify any flaws from that lens. If the lens is already soft the shots will be softer with a converter. I have Canons 1.4 converter and do use it on occasion when I need the reach. On my 70-200 f2.8 I can get acceptable shots (by my standards) at the 200 end. On my 400 f2.8 however I love it. The 400 f2.8 is an incredibly sharp lens and the IQ degradation is very acceptable with the 1.4 on it.

Personally I prefer the 1.4X to the 2X converter. The extra reach of the 2X also means an increase in IQ degradation.

 

[Overread]

Firstly check the manufacturers website to make sure your lenses can take the teleconverter - the canon line only work for selected (most) L lenses in the range - sigma and tamron lines do work well though with many lenses.
But yes you are right - they are adding glass to a lens setup and so do lower the overall quality of shot and also increase the amount of light you need to get a good shot (and also lower your maximum aperture - 1.4 times is by one stop and 2 times is by two stops).
However you are right that they are a good and cheap way to add focal length to a lens - however unless you are using top range lenses you won't gain enough range to counter the loss in quality. Most 1.4 times on a top range lens add focal length with minimal losses of light and quality - its a very worth while and popular teleconverter to use - the 2 times is more of a gamble - more range, but more restructions and limitations.
Further primes are far better at this than zooms (especially with the 2 times teleconverter

 

[mike11165]

i consider myself enlighted by you two, thanks for taking the time to teach a noob.

 

[Battou]

i consider myself enlighted by you two, thanks for taking the time to teach a noob.

Look in just for fun, Overread posted a topic about exparimenting with two teleconverters on a mid range zoom to extend it to 800mm.

If I had a good 200mm tele I would offer up a 200/2xconvert vs 400mm tele, but sadly I do not have the 200mm at this time.

*EDIT*
http://thephotoforum.com/forum/showthread.php?t=131121

 

[Garbz]

As said you lose quality but I generally find it to not be as bad as actually upsampling the image. (and before someone shouts genuine fractals, note that my teleconverter cost as much as that piece of software)

2x teleconverters are generally pushing it for any lens you mount it on but certainly 1.4x (I use) and 1.7x are widely used for giving a bit of extra reach to existing good lenses.

Also note that this is not one of the times to be brand proud. A quick google search will show that Kenko regardless of their poor other products make a fantastic teleconverter, and definitely a much higher bang for buck and far better supported product (Doesn't lose AF on any lens) then even Nikon's own. (no comment on Canon)

I suggest take the camera into a shop which sells them and have a play at the counter, let me know if you want example shots for a 1.4x and I'll go take some tomorrow.

 

[Bifurcator]

...and before someone shouts genuine fractals...

Hehehe was that to me? But no need for the prevention I totally agree. Genuine Fractal is nice but I would MUCH rather work with a TC given the option of the two!

 

[usayit]

Yes... Image quality is compromised but I wouldn't consider them "trash".

cropping versus 2x converter? I'd take the 2x converter.

not getting the shot versus 2x converter? I'd take the 2x converter and enjoy shooting

300mm AND 600mm versus 2x converter AND 300mm on a long long hike? I'd take a 2x converter (unless you have a human mule to carry the 600mm it for you).

 

[table1349]

Trust me, I have seen this lens:
Phoenix Zoom Telephoto 100-300mm f/5.6-6.7 Autofocus Lens for Canon EOS $109.99

With this TC:
PHOENIX 2X TELE CONVERTER AF CANON EOS $69.00


The shots are not worth taking.

It isn't that way with every TC or lens, but it important for the OP to understand that the TC will magnify the faults of the lens as well as the faults of the TC.

 

[table1349]

As said you lose quality but I generally find it to not be as bad as actually upsampling the image. (and before someone shouts genuine fractals, note that my teleconverter cost as much as that piece of software)

2x teleconverters are generally pushing it for any lens you mount it on but certainly 1.4x (I use) and 1.7x are widely used for giving a bit of extra reach to existing good lenses.

Also note that this is not one of the times to be brand proud. A quick google search will show that Kenko regardless of their poor other products make a fantastic teleconverter, and definitely a much higher bang for buck and far better supported product (Doesn't lose AF on any lens) then even Nikon's own. (no comment on Canon)

I suggest take the camera into a shop which sells them and have a play at the counter, let me know if you want example shots for a 1.4x and I'll go take some tomorrow.

:thumbup: Got to agree with Garbz. I had the Kenko DG 300 1.4X converter. I thought it was as good as the Canon at half the price.

 

[icassell]

I have the Sigma 1.4X and the Sigma 2X to use with my SIgma EX glass. They degrade IQ somewhat and the 2X more than the 1.4X, but both often give very good results. I've stacked them on my Sigma EX 100-300 f4 zoom -- not great, but don't know how else I could ever afford an 820mm lens! I bought my TC's on ebay at very good low prices.

 

[Joves]

I used to use them in the film days but, only if absolutely needed. I think I will look at that Kenko though. I dont mid a 1.4/1.7 but, never really liked the 2x. Id rather have glass that reaches out than use a converter. I know my next long range is going to be the Sigma 300-800. And I wont mind carrying it in my pack either.

 

[Overread]

true - one would always prefer the longer glass to the teleconverter - but when a TC is only a little over £100 whilst good longer lenses can be £2000-£5000 (think 600mm) its a good bargin whilst you wait I feel

 

[LWW]

As said you lose quality but I generally find it to not be as bad as actually upsampling the image. (and before someone shouts genuine fractals, note that my teleconverter cost as much as that piece of software)

I agree.

GF however:

- Doesn't add weight that I have to carry.
- Never has to be taken on and off during a shoot.
- Doesn't cost me any f stops.
- Doesn't act as a further light lever ampluifying small movements when handheld.
- Doesn't take up room in the camera bag.
- Does still leave me with the sharper original if I don't like the results.

LWW

 

[Garbz]

That's obvious but for more than 20 times the cost of a 300mm f/4 vs slapping a $100 teleconverter on my existing 200mm f/2.8 it is something I am very very much to sacrifice. And that is exactly the key here. It's just another option. Weigh up the costs and benefits.

The major benefit is that you won't die a horrible death in pursuit of the elusive mm like another member of the forum will shortly. http://www.thephotoforum.com/forum/showthread.php?t=134288