# Tamron 31A (200-500 5.6) vs Pentax 150-450 4.5-5.6

Started 4 months ago | Questions
 Forum
Re: Tamron 31A (200-500 5.6) vs Pentax 150-450 4.5-5.6

gkreth wrote:

xmeda wrote:

gkreth wrote:

xmeda wrote:

Get Sigma 100-300/4 and be happy With K3 you have same reach as 150-450 on FF

Well, yes, a 300mm on a K3 has the reach of a 450mm on FF, but 450mm on a K3 has the reach of a 675mm!
Just looking for more reach, without dropping \$1500....
Greg

You can always slap 1.5x TC or 2xTC on it and get 150-450/6.3 or 200-600/8

Wait, is that correct?

• A 1.5X TC decreases the aperture by one full stop; so a f/5.6 would be f/8, not f/6.3.
• A 2X TC decreases the aperture by two stops; ; so a f/5.6 would be f11, not f/8.

Am I missing something?
Greg

missing Sigma 100-300/4

-- hide signature --

http://pentax.xf.cz/ - Personal page about my favourite system.

xmeda's gear list:xmeda's gear list
Casio QV-R40 Casio Exilim EX-Z110 Olympus XZ-1 Pentax X-5 Olympus XZ-2 iHS +43 more
Complain
Re: Tamron 31A (200-500 5.6) vs Pentax 150-450 4.5-5.6

xmeda wrote:

gkreth wrote:

xmeda wrote:

gkreth wrote:

xmeda wrote:

Get Sigma 100-300/4 and be happy With K3 you have same reach as 150-450 on FF

Well, yes, a 300mm on a K3 has the reach of a 450mm on FF, but 450mm on a K3 has the reach of a 675mm!
Just looking for more reach, without dropping \$1500....
Greg

You can always slap 1.5x TC or 2xTC on it and get 150-450/6.3 or 200-600/8

Wait, is that correct?

• A 1.5X TC decreases the aperture by one full stop; so a f/5.6 would be f/8, not f/6.3.
• A 2X TC decreases the aperture by two stops; ; so a f/5.6 would be f11, not f/8.

Am I missing something?
Greg

missing Sigma 100-300/4

Ah, I see, now. Well, that brings up an interesting point....
I already have the 60-240 f/4, as well as the Tamron 1.4x TC and Tamron 2x TC.
I suppose I could try playing with those combinations, to see what I get. Of course, with the 1.4x, I'm only getting to 336mm, so I'd really have to use the 2x.
For quite some time, I searched eBay for a Sigma 100-300 f/4; I think I stopped looking when I got the 60-240.

Complain
Re: Tamron 31A (200-500 5.6) vs Pentax 150-450 4.5-5.6

gkreth wrote:

xmeda wrote:

gkreth wrote:

xmeda wrote:

gkreth wrote:

xmeda wrote:

Get Sigma 100-300/4 and be happy With K3 you have same reach as 150-450 on FF

Well, yes, a 300mm on a K3 has the reach of a 450mm on FF, but 450mm on a K3 has the reach of a 675mm!
Just looking for more reach, without dropping \$1500....
Greg

You can always slap 1.5x TC or 2xTC on it and get 150-450/6.3 or 200-600/8

Wait, is that correct?

• A 1.5X TC decreases the aperture by one full stop; so a f/5.6 would be f/8, not f/6.3.
• A 2X TC decreases the aperture by two stops; ; so a f/5.6 would be f11, not f/8.

Am I missing something?
Greg

missing Sigma 100-300/4

Ah, I see, now. Well, that brings up an interesting point....
I already have the 60-240 f/4, as well as the Tamron 1.4x TC and Tamron 2x TC.
I suppose I could try playing with those combinations, to see what I get. Of course, with the 1.4x, I'm only getting to 336mm, so I'd really have to use the 2x.
For quite some time, I searched eBay for a Sigma 100-300 f/4; I think I stopped looking when I got the 60-240.

Sig100-300/4 is all-metal FF fast focusing hi-end single tube lens and if you manage to find good EX DG sample, you will never regret. If only Ricoh created similar tool with latest glass technology... it is large and heavy, but still not like Sigma 120-300/2.8 and I do not understand why Sigma stopped that lens. Maybe due to problematic OS implementation in such design for other systems, but now they can re-use it again for ILC cameras with IBIS. With F4 it is the sweet spot between providing lens fast enough while still keeping it in usable size, weight and price. And with constant F4 it is better for video than variables.

I have Pentax F1.7xAF TC and Kenko SHQ 1.5x and 2x.
1.7x AFTC is doing AF through TC adaptor, image quality is acceptable, SR needs focal length input manually.
1.5x Kenko jut transfers everything through, but sometimes it is better to switch SR off and just use fast shutter speed 1/500s+ as otherwise camera still thinks that 300mm is mounted on, image output is comparable to DA55-300 output at 300mm if we talk about resolution.
2x Kenko again transfers everything, SR off and fast shutter is needed, Ideally around 1/1000s, some drop of image output, especially contrast is there, AF is slower and not that reliable, but you still have AF 600mm F8. Good on tripod, not that good hand-held, but usable. Original Sigma TC might do better job there.

I wonder why it is not allowed to set focal lenght manually and override what lens provides through contacts. That will simplify TC usage so much...

-- hide signature --

http://pentax.xf.cz/ - Personal page about my favourite system.

xmeda's gear list:xmeda's gear list
Casio QV-R40 Casio Exilim EX-Z110 Olympus XZ-1 Pentax X-5 Olympus XZ-2 iHS +43 more
Complain
Re: Tamron 31A (200-500 5.6) vs Pentax 150-450 4.5-5.6

xmeda wrote:

gkreth wrote:

Ah, I see, now. Well, that brings up an interesting point....
I already have the 60-240 f/4, as well as the Tamron 1.4x TC and Tamron 2x TC.
I suppose I could try playing with those combinations, to see what I get. Of course, with the 1.4x, I'm only getting to 336mm, so I'd really have to use the 2x.
For quite some time, I searched eBay for a Sigma 100-300 f/4; I think I stopped looking when I got the 60-240.

Sig100-300/4 is all-metal FF fast focusing hi-end single tube lens and if you manage to find good EX DG sample, you will never regret. If only Ricoh created similar tool with latest glass technology... it is large and heavy, but still not like Sigma 120-300/2.8 and I do not understand why Sigma stopped that lens. Maybe due to problematic OS implementation in such design for other systems, but now they can re-use it again for ILC cameras with IBIS. With F4 it is the sweet spot between providing lens fast enough while still keeping it in usable size, weight and price. And with constant F4 it is better for video than variables.

I have Pentax F1.7xAF TC and Kenko SHQ 1.5x and 2x.
1.7x AFTC is doing AF through TC adaptor, image quality is acceptable, SR needs focal length input manually.
1.5x Kenko jut transfers everything through, but sometimes it is better to switch SR off and just use fast shutter speed 1/500s+ as otherwise camera still thinks that 300mm is mounted on, image output is comparable to DA55-300 output at 300mm if we talk about resolution.
2x Kenko again transfers everything, SR off and fast shutter is needed, Ideally around 1/1000s, some drop of image output, especially contrast is there, AF is slower and not that reliable, but you still have AF 600mm F8. Good on tripod, not that good hand-held, but usable. Original Sigma TC might do better job there.

I wonder why it is not allowed to set focal length manually and override what lens provides through contacts. That will simplify TC usage so much...

Yeah, I think that's why I stopped using TCs; I rely a lot on SR.

Right now on vacations I take a Panasonic FZ1000; it seems like a nice compromise between size/weight, no lens-swapping, IQ, and range (24mm-400mm).
But sometimes I miss the larger sensor, and wonder if it's worth hauling around a 500mm. I guess I should walk around some of the local parks with my current 50-500, and see after an hour if I really want to take a 50-500 on vacation... LOL!

Greg

Complain
Re: Tamron 31A (200-500 5.6) vs Pentax 150-450 4.5-5.6

gkreth wrote:

I guess I should walk around some of the local parks with my current 50-500, and see after an hour if I really want to take a 50-500 on vacation... LOL!

LOL! ... I doubt you will want to ... I love my 50-500mm DG OS HSM... but it's not my standard holiday or walking around lens! It is specifically only my wildlife lens, and then only for shooting wildlife from a vehicle in daylight.

In Zambia I also do night game drives (which are permitted in Zambian national parks), and for that a 70-200 f/2.8 is the best tool for the job. In Zambia I also do walking safaris (photography on foot with a guide and armed ranger), I always use my DA 18-270 for that or sometimes a Sigma 18-300. Walking safaris are more about the small things that you don't notice from a vehicle, but you can and do walk into big game as well. While most African wildlife is comfortable letting vehicles approach fairly close, most are not as comfortable with humans on foot. So, birds and prey species tend to keep their distance, and prudent walkers keep their distance from dangerous game. Thus, light superzooms like the DA 18-270 SDM are great lenses for this.

Greg

PentUp's gear list:PentUp's gear list
Panasonic Lumix DMC-FZ300 Pentax K-x Pentax K-5 II Pentax K-50 Pentax K-3 Mark III +11 more
Complain
Re: Tamron 31A (200-500 5.6) vs Pentax 150-450 4.5-5.6

gkreth wrote:

Yeah, I think that's why I stopped using TCs; I rely a lot on SR.

Right now on vacations I take a Panasonic FZ1000; it seems like a nice compromise between size/weight, no lens-swapping, IQ, and range (24mm-400mm).
But sometimes I miss the larger sensor, and wonder if it's worth hauling around a 500mm. I guess I should walk around some of the local parks with my current 50-500, and see after an hour if I really want to take a 50-500 on vacation... LOL!

Greg

Thats perfect situation for some OMD EM10II and Oly 75-300 Small, but long.

...or:

MF, but..

-- hide signature --

http://pentax.xf.cz/ - Personal page about my favourite system.

xmeda's gear list:xmeda's gear list
Casio QV-R40 Casio Exilim EX-Z110 Olympus XZ-1 Pentax X-5 Olympus XZ-2 iHS +43 more
Complain
 Forum