Pentax SMCP-DA* 300mm f/4 ED

koper · 07-22-2008, 12:00 AM

i would like to know which teleconvecter i can use for this lensess???
1.kenko 1.5 * tc dose not work whis this lensess
2.bower tc can be used with manual focus

i have pentax kd10 pentaxk d20 camera

???????

jgredline · 07-22-2008, 12:28 AM

Here you go. You will find all u need here.

TAMRON TC converter pics

koper · 07-22-2008, 03:04 AM

the photos which you refere was made with Tamron 1.4 TC and Sigma 70-300APO
not with Pentax SMCP-DA* 300mm f/4 ED
i have sigma 70-300 lensess and they work good with kenko 1.5 * tc
the lensess did not work with Pentax SMCP-DA* 300mm f/4 ED
do you have experience with this lenses????

Ishpuini · 07-22-2008, 05:40 AM

Trouble is SDM. None of the TCs on the market currently enable SDM to continue working, even if they have powerzoom contacts.

Possibly an AF TC without powerzoom would have the SDM lens revert to using the in-body AF, but I haven't been able to test this. I once tried a DA*300/4 on my Sigma EX2x to check if it mounted, but there wasn't enough light in the store to check whether AF worked. It did mount, so MF would have been possible.

I think the only option allowing AF would be the old F1.7x AF converter made by Pentax, because that has its own internal AF system, blocking out all or almost all electronic communication from the lens.

Wim

koper · 07-22-2008, 06:06 AM

thank you for your advice

Pål Jensen · 07-22-2008, 06:24 AM

Originally Posted by koper

i would like to know which teleconvecter i can use for this lensess???
1.kenko 1.5 * tc dose not work whis this lensess
2.bower tc can be used with manual focus

i have pentax kd10 pentaxk d20 camera

???????

There is a Pentax dedicated teleconverter in the works. It will probably be released by the end of the year....

koper · 07-22-2008, 07:23 AM

thank you for information

jgredline · 07-22-2008, 09:15 AM

Originally Posted by koper

the photos which you refere was made with Tamron 1.4 TC and Sigma 70-300APO
not with Pentax SMCP-DA* 300mm f/4 ED
i have sigma 70-300 lensess and they work good with kenko 1.5 * tc
the lensess did not work with Pentax SMCP-DA* 300mm f/4 ED
do you have experience with this lenses????

I hope your not refering to the first page, because buried someplace in the 20's there are examples of mine and others using the DA*300 f/4.0 with Tamron MC-4 TC working well with the SDM lenses...No such luck . atleast for me with the Kenko 1.5tc..