teleconverter??

[yokechye]

i still have quite a vague understanding of teleconverters for km/sony lens.

is there something like some lens cant fit onto the teleconverter or you need to be at f/X in order to use the AF??

I read something on ebay like Auto Focus on Lens with wide aperture of 2.8 and higher.
Manual Focus on lens with smaller f stops.

so it means if my lens is f/5.6 it it cant AF?

[thinkvision]

trust me, 300/2.8 more reliable...

[yokechye]

i was thinking like extending my 500 range to like 700 or more... but of course it will lose quality and need MF isnt it?
then sigma 800 is comfirm out of my range. another option is to get a telescope

[Del_CtrlnoAlt]

Originally Posted by yokechye i was thinking like extending my 500 range to like 700 or more... but of course it will lose quality and need MF isnt it? then sigma 800 is comfirm out of my range. another option is to get a telescope

50-500 with 1.4 still can AF...

[thinkvision]

found one sharp used canon 800/5.6L, modify its FD to M42...no regret!@

[yokechye]

Originally Posted by Del_CtrlnoAlt 50-500 with 1.4 still can AF...

very tempting leh... but i not enough cash now

[Darcy.Zhou]

Originally Posted by Del_CtrlnoAlt 50-500 with 1.4 still can AF...

haha

looks like 50-500/f1.4 constant...

[yokechye]

Originally Posted by Darcy.Zhou haha looks like 50-500/f1.4 constant...

if 50-500 f/1.4 for 1.2k i go chiong for it liao

[Drudkh]

You need to know how is the structure of the TC and the rear element of the lens you'll be using. An example: Minolta 80-200 f/2.8 and Minolta TC.

[yokechye]

Originally Posted by Drudkh You need to know how is the structure of the TC and the rear element of the lens you'll be using. An example: Minolta 80-200 f/2.8 and Minolta TC.

so the rear lens element comes out too much that it cant fit onto the TC?

[Drudkh]

Yes, they collide onto each other. To solve the problem is to buy 3rd party TC like Teleplus or Kenko which has an allowance catered for such lenses. If I'm not wrong, Sigma TCs are the same as Minolta's.

[yokechye]

so Auto Focus on Lens with wide aperture of 2.8 and higher.
Manual Focus on lens with smaller f stops.

so does that means that if my lens is at f/5.6 it is MF?

[Galdor]

Originally Posted by yokechye so Auto Focus on Lens with wide aperture of 2.8 and higher. Manual Focus on lens with smaller f stops. so does that means that if my lens is at f/5.6 it is MF?

No leh, I use my TelePlus with my Sigma 400mm f5.6 and it can AF leh.

[yokechye]

Originally Posted by Galdor No leh, I use my TelePlus with my Sigma 400mm f5.6 and it can AF leh.

teleplus 1.4? if 3x then how?

sigma 170-500 f5-6.3 can still AF?

[Galdor]

Originally Posted by yokechye teleplus 1.4? if 3x then how? sigma 170-500 f5-6.3 can still AF?

Not sure leh. Don't have either of these.

[yokechye]

Originally Posted by Galdor Not sure leh. Don't have either of these.

3x super tele sia... can shoot FF moon

[Galdor]

Originally Posted by yokechye 3x super tele sia... can shoot FF moon

But dun know how's the quality leh. Can get the range but may not be sharp.

[yokechye]

Originally Posted by Galdor But dun know how's the quality leh. Can get the range but may not be sharp.

ya lo.. thats what i worry

[Galdor]

Originally Posted by yokechye ya lo.. thats what i worry

Dun think it's advisable to get a 3X T/C. Get a 2X one instead.

[clkoh]

Originally Posted by yokechye teleplus 1.4? if 3x then how? sigma 170-500 f5-6.3 can still AF?

Woah you need 1500mm? Shoot neighbour?

1.4X TC adds 1 stop, 2X adds 2 stops, and 3X 3 stops. F6.3 add 3 stops, it will be so dark you have difficulty to even to manual focus! Need very bright light. Cannot shoot moon, but maybe the sun?

Have tried Kenko Pro 300 1.4 with Tamron 200-500. At 500mm, can AF, but sometimes keeps hunting when lighting is no good. When it happens just switch to manual lor. If not wrong Tankm have 2x, maybe he can answer.

By the way, Sony 50mm/1.4 cannot fit into this Kenko 1.4 TC.

If for birding, another cheaper option is to look at Digiscoping.