1.4x or 2x teleconverter?

[swimcraze]

hi, am at a loss which range of teleconverter i should buy.
from what i read, 1.4x will retain the quality in the photos.
but 2x seems like a good buy since it helps me to get a max reach.

sigh.....am thinking of getting kenko pro series.

will be using the TC on 90mm 2.8 and 180mm 2.8 lens.

please advise.

thanks.

 

[clive]

if u get the 2x...then using it on the 90mm defeats the purpose of having the 180mm lens :bsmilie: ie if u buy the 2x then it will solely be meant for the 180mm

if u get 1.4x...then u end up with "obscure" focal lengths like 126mm/f4, 252mm/f4 :think: for this i rather get a "pure" 135mm/f2 or 300mm/f4 lens...

actually having 90mm and 180mm is good enuff already for most applications...this is akin to owning a 70-200/2.8 and using mainly using it between 2 extreme ends...

so...

i suggest u go for 2x ;-)

 

[mr_jason]

2x on a 180mm lens would mean 360mm. Factoring in the crop factor assuming you're using a DSLR would be 576mm. Which means you will need around 1/600s if you're handholding, which is rather insane. Also remember the loss of 2 stops of light, which means it would be virtually an impossible combination to handhold. What kind of subjects are you shooting that you need such a working distance?

For butterlies which are one of the hardest subjects to shoot, I would agree that the working distance is needed, but if you were to tripod mount the 2x + 180mm combination, your shutter would be very slow due to the 2 stops of light loss. Butterflies are very fast and do not stay still for long. Even when still, they still move a bit. Therefore anything slower than 1/80s I feel would result in motion blur on the insect's part.

For most other sorts of insects which are less skittish or territorial like dragonflies you can go nearer and mount your tripod or handhold, and thus do not really need the 2x + 180mm combo.

The 1.4x combination with 180mm would be a better combination by far.

 

[rayfoo]

2x on a 180mm lens would mean 360mm. Factoring in the crop factor assuming you're using a DSLR would be 576mm. Which means you will need around 1/600s if you're handholding, which is rather insane. Also remember the loss of 2 stops of light, which means it would be virtually an impossible combination to handhold. What kind of subjects are you shooting that you need such a working distance?

erm...u meant 1/60s right? :bigeyes:

 

[justarius]

erm...u meant 1/60s right? :bigeyes:

He's correct, its 1/600s going by the rule of thumb of 1/focal length. Effective focal length in this case if swimcraze is using a DSLR is 576mm as mr_jason has calculated.

 

[swimcraze]

well, i am not a DSLR user....and not thinking of plunging into one for now.
currently using manual cameras for my set up.

1.4x x 180mm = 252mm (not much of a difference?)
was told by someone via pm that 1.4x converters are used more for the 300mm range where it makes more sense 1.4x x 300mm = 420mm

2x x 180mm = 360mm (sounds good to me.....you think?)

thanks for all your help and contributions.

looks like 2x is what i should get....

unless someone thinks otherwise?????

do share.

thanks.

 

[shutterbug]

How much does you kenko 2x TC cost? Have you considered getting another lens instead?

 

[justarius]

How much does you kenko 2x TC cost? Have you considered getting another lens instead?

hehe, since swimecraze is gonna use it on his 180mm, getting another lens to get an equivalent reach would be venturing into the realmes of the big mama telephotos. Costwise, the TC wins everytime.

 

[mpenza]

kenko pro 300 1.4x or 2x costs ~$300.

There's also a kenko pro 3x but I think it's not highly rated.

 

[willyfoo]

Yes... 2x gets u the reach.. but it results in a softness that makes my pictures unusable... therefore I don't even use my 2x.

I would wait for the 1.7x and wait for the reviews on how it compares in terms of quality.

 

[Ah Pao]

He's correct, its 1/600s going by the rule of thumb of 1/focal length. Effective focal length in this case if swimcraze is using a DSLR is 576mm as mr_jason has calculated.

Actually don't need to factor in the focal length multipler in a DSLR since it's just a crop factor rather than a real multiplication of the focal length.

So, 2x 180mm = 360mm, going by the 1/(focal length) rule to effectively stop camera shake will need 1/350 sec or faster--which is still quite fast.

 

[Zerstorer]

Just remember that the crop factor means that the "cropped" image renders a full image on the CCD rather than on just part of it. In that sense, any smearing caused by movement will be magnified by a certain amount as well, hence the 1/focal length guide is still valid.