Hi all,

I am thinking of extending the reach of my SAL18250 as I find it's reach too short for
shooting wild life like at Sungei Buroh Wetland. To get a super zoom at this stage of my experience is not due yet.

Reading from the net, there is a choice of 1.4x or 2x TC. While they are compatible with super zoom teles, I wonder whether TC would be appropriate for a general purpose zoom like the SAL18250 lens.

Also there is the choice of Sigma or Sony brands.....& maybe others too.

Comments are welcome.

If I remember correctly, there isn't any telecon that works with 18250. Sorry dude. But the 70400 lens is a good choice if you need an extended range :)

Usually teleconvertors are used with lens of f4 aperture and larger. Reason being when a teleconvertor is used, there is light loss. A 1.4x TC will reduce 1 stop of light while a 2x TC reduce 2 stops. If a general lens like the 18-250 is used with a 1.4x TC, the largest aperture at the 250mm end will from f6.3 become f9. At f9, your viewfinder would be too dark and auto-focusing may fail.

Great stuff, Keith!

I've learned something new from you today... ^_^

Tks all,

I appreciate the advice & feedback.

But can manual focus help?

If not, I will have to live with the short reach until I struck 4D &
go for a super zoom:( :rolleyes:

I just realized someone is selling his kit SAL70300 lens.

Is this lens compatible with a TC 1.4x or 2x?

if i remember correctly sony telecons only compatible with 135mm f/2.8 STF, 300mm f/2.8 G, 70-200mm f/2.8 G and 70-400mm f/4-5.6 G

If using manual focus, the problem you will encounter is very hard to get accurate focus because the view finder is dark (akin to seeing at night with dim lights)

The 70-300mm has a largest aperture of f5.6 at the 300mm end. With a 1.4x convertor, intake of light from f5.6 becomes f8, unless using in bright daylight otherwise hard to use.