[imtheguy]

I quit 2x teleconverters years ago since the loss of IQ was always worse than just cropping. However the Sigma 1.4x on their 500mm prime exceeded my expectations. Now I wonder if the 2x TC has a chance to do the same. Has anybody here in PF tried that combo and wish to recommend it? any pictures posted?

Thanks in advance.

[oeriies]

I quit 2x teleconverters years ago since the loss of IQ was always worse than just cropping. However the Sigma 1.4x on their 500mm prime exceeded my expectations. Now I wonder if the 2x TC has a chance to do the same. Has anybody here in PF tried that combo and wish to recommend it? any pictures posted?

Thanks in advance.

Hi Lee,

I've got the 2x Sigma TC. It will autofocus pretty well on the Sigma 500 f/4.5. I've not systematically tested cropping vs. the TC. My impression is that conditions have to be really prime to make it worthwhile to use the 2x, by which I mean a lot of light, a stable tripod, and a subject that isn't moving. I'll take the Sigma 1.4x or Tamron 1.4x with me when I'm out for a walk with my Sigma 500 but not the Sigma 2x. In that sense it is a specialized and infrequently used piece of my kit. I'll be interested in any other feedback you get.

Russ

[imtheguy]

Hi Lee,

I've got the 2x Sigma TC. It will autofocus pretty well on the Sigma 500 f/4.5. I've not systematically tested cropping vs. the TC. My impression is that conditions have to be really prime to make it worthwhile to use the 2x, by which I mean a lot of light, a stable tripod, and a subject that isn't moving. I'll take the Sigma 1.4x or Tamron 1.4x with me when I'm out for a walk with my Sigma 500 but not the Sigma 2x. In that sense it is a specialized and infrequently used piece of my kit. I'll be interested in any other feedback you get.

Russ

Thanks for the feedback. Sounds like I will have to give it a try for those bright days shooting from the deck. Still, I will be surprised if the 2x pic looks even as good as a cropped 1.4x shot. But only one way to be sure. If the 500 will still AF that is a real bonus.

If I am a good PF member I will post some comparisons.

[Lowell Goudge]

Just a simple question he but which version of the 500/4.5 and TCs, the screw drive or HSM version

[imtheguy]

Just a simple question he but which version of the 500/4.5 and TCs, the screw drive or HSM version

I would love to have quiet HSM version but did not think they were available in Pentax mount. Yep, got the screw-drive.

[Lowell Goudge]

I would love to have quiet HSM version but did not think they were available in Pentax mount. Yep, got the screw-drive.

I was wondering because I see the sigma site now seems to offer an HSM TC for Pentax. They show only the 500/4.5hsm and show AF with then1.4 x and only MF with the 2x due to total lens plus TC speed

[stormtech]

Is this something new - the Sigma 500 4.5 with HSM?

Here is a snip from the B&H page for the lens:

Product Highlights

• Super Telephoto Prime Lens
• Aperture Range: f/4.5-32
• Hyper-Sonic Motor
• Inner Focusing System
• Extra Low Dispersion Elements
• Fits Full-Frame and APS-C Sensors
• For Pentax K Mount

From what I've read, this lens was only screw drive for Pentax. If the HSM is true, it's a big step up!

[derekkite]

I think it's a mistake, has been like that for a while. It looks like they copy and paste.

[stormtech]

I think it's a mistake, has been like that for a while. It looks like they copy and paste.

OK. Man, I would be pretty upset if I ordered this lens and it wasn't HSM when it arrived........

[ElJamoquio]

It's a mistake, it's always been screw-drive for Pentax.

[Just1MoreDave]

Thanks for the feedback. Sounds like I will have to give it a try for those bright days shooting from the deck.

I hope your deck is built better than mine! (mine is not quite stable enough for 1000mm)

[cmohr]

I use the 2xTc on my 300/2.8 ad yet IQ is not quite that of the 1.4xTC, but I'm sure someone good with PP would make up for a lot. And, I only use the 2x on bright condition, say good sunny day photographing Surfing, other than that I stick with the 1.4xTC its a ripper.

[oeriies]

I quit 2x teleconverters years ago since the loss of IQ was always worse than just cropping. However the Sigma 1.4x on their 500mm prime exceeded my expectations. Now I wonder if the 2x TC has a chance to do the same. Has anybody here in PF tried that combo and wish to recommend it? any pictures posted?

Thanks in advance.

I conducted a quick test today. I shot the test chart in the first photo below from about 32', which was the distance at which the chart filled the frame of my K-5 with Sigma 500mm F4.5 and Sigma 2x TC attached. I was outdoors in good late afternoon light. I shot several frames at f5.6, ISO between 100-200 as reported by the K-5 (actually it was 2 stops slower than f5.6 because the Sigma TC simply passes through the info from the lens to which it is attached -- the K-5 doesn't know about the TC). The camera was locked down on a good quality tripod and gimbal. I used autofocus. I fired the shutter remotely 6 sec after mirror lock-up. Then I removed the TC and did the same thing again with the same f -stop and ISO, letting shutter speed go up to keep roughly the same exposure values. Then I cropped both sets of photos to display the same field of view on the most telling part of the test chart. Two samples are reproduced below.

Every sample generated the same conclusion: The images taken with the Sigma 2x TC (e.g., the first example) are sharper than from the images w/o the TC (the second example) when the latter images are cropped to the same field of view as those obtained with the TC. I think the difference is clear from the attached jpegs. It is crystal clear with the raw files. This surprised me and will affect my behavior going forward -- like I may actually use the 2x TC.

Russ

[imtheguy]

I hope your deck is built better than mine! (mine is not quite stable enough for 1000mm)

I think mine would work with 10,000mm. Its slab concrete that does not sway in the breeze.

[imtheguy]

Every sample generated the same conclusion: The images taken with the Sigma 2x TC (e.g., the first example) are sharper than from the images w/o the TC (the second example) when the latter images are cropped to the same field of view as those obtained with the TC. I think the difference is clear from the attached jpegs. It is crystal clear with the raw files. This surprised me and will affect my behavior going forward -- like I may actually use the 2x TC.

Russ

I don't know if I am more impressed that the 2x TC is sharper or that the lens could accurately focus with it. Both are surprises to me and it will cost me $249 at B&H as soon as I submit this. Many thanks for the test!