Telconvertors

[satay16]

Hi. After doing some research on teleconvertors, I am now even more confused. Kenko has MC4 MC7 300pro. and there are others which are generic and dedicated with some dedicated ones which can actually be generic . so what exactly are their differences? i am looking for a 2X and able to fit on all lenses(esp my sigma 70-200). btw, iam using minolta mount. thanks!

 

[pai]

here, knock urself out ;p : http://dyxum.com/lenses/TC/index.asp

warn u first, 2x teleconverters are going to make your images a fair bit softer. you can try borrowing one from the km forum ppl and see for yourself.

 

[satay16]

yah...that was that exact site which made me slightly confused. is a kenko pro300 considered as generic or dedicated? it seems to be compatible with quite some lenses stated in the webbie.

 

[pai]

pro300 better than mc7 better than mc4, but you're right, it's hard to tell which lenses will or won't work with the pro300. from what it says on the site, it's not a generic TC, and is meant for the better minolta/tokina/tamron lenses.

i guess the mc7 is the best generic tc that is guaranteed to work with your sigma. if you do somehow find someone selling off a pro300 in minolta mount, suggest you don't buy unless you try.

otherwise you'll have to wait for someone who's got the pro300 and a similar sigma lens to answer your question.

 

[dr34mc4st3r]

70-200 f2.8 + 2x TC = 140-400 f5.6

might as well buy a prime 400mm f5.6 lens

 

[tankm]

To be sure the TC can work with all your lens, the TC center element must not stick out at all. If the TC center sticks out, it may hit against the rear lens element of your lens during mounting which will cause damage to the TC and lens.

So far, the only dedicated TC that I'm aware of are those from Minolta and Sigma, cause their TC center element stick out alot and can only be used on lens where the rear lens element are sitting far back into the lens body.

For your SIGMA 70-200 f2.8, I have used a dedicated SIGMA 1.4x APO TC on it and it match up nicely and produce very good result. You will have no problem using the Kenko Pro 300 TC with this lens. The Kenko Pro 300 TC does stick out slightly compare to those truly generic type, hence it may not be compatible with some lens. On the website it does list a long list of lens that are compatible with the Kenko Pro 300 TC.

As for quality, usually 7 elements type are better than 4 elements type. For the same TC quality, a 1.4x TC produce better result than a 2x TC on the same lens.

Use 2xTC only when you really have no choice. 1.4xTC so far, produce very good result. 1.7xTC is a good compromise to get a slightly better reach than a 1.4xTC but doesn't degrade image quality as much as the 2xTC, but it's very rare to find one for the Sony/Minolta mount.

Last time I asked around for the Kenko Pro 300 for Minolta/Sony mount in Singapore, cannot find at all. It's best to wait until the SONY A-100 becomes more popular and then most probably the shops will bring in stock for it. If you want to buy it today, only option is B&S or direct order from US or Europe.

All the best in your TC search.

yah...that was that exact site which made me slightly confused. is a kenko pro300 considered as generic or dedicated? it seems to be compatible with quite some lenses stated in the webbie.