[mkymic]

Anyone using this combination .
Would like to here your thoughts about it
before I pull the trigger on lens
mkymic

[pearsaab]

@weevil has it

[normhead]

I'm pretty sure Gary Chalker (Ducatigaz) used it at one time.

[mkymic]

Thank you Gentlemen
I had noticed both those names earlier.
and I guess I was fishing for them with my post .
I believe Mr. Chalker did the comparison between
the Sigma 500 and the Pentax 560.

[C_Jones]

I have the Sigma 150-500 DG OS for Pentax. It does very well. I bought it before the Pentax 150-450 was available (manufactured). I use an aps-c lens on it (K-5 IIs) and the images I get from it are really nice. I have a K-1 II, but I use my Pentax 70-200 on it. I am not sure if you are planning on doing some birding or wildlife shooting with a K-1 and 150-500 combination, but I as I said use the aps-c lens (K-5 IIs) to have the original image reach (750). If you use it with the K-1 you will have crop options due to a high megapixel count on it, but I prefer using the aps-c body with the lens to begin with and still getting reasonable crops from original images if I need them.

So it is really up to you, whether you would prefer shooting super telephoto with a full frame body (K-1) or an aps-c body. The 150-500 lens is capable of excellent images, but if the 150-450 (Pentax) had been available to me at the time I purchased the 150-500 I most likely would have purchased the 150-450. I have never used the 500 lens itself, but with me having the versatility of the zoom range on the 150-500 is a very valuable asset for shooting at different distances and being able to compose a shot.

[C_Jones]

This is an example of a crop of a shot I took with my Sigma 150-500 DG OS for Pentax this May. It was on my K-5 IIs. The bird is a Tern.

[cmohr]

Yes, I have one, and really like it on the K-1, very easy to handhold as it's not that big or heavy, you can easily move and swing it around when a bird appears out of the blue. It is easy to use for extended periods. Fits in a backpack and it again, light enough to trek to locations with.
I find the AF quick and it locks on well, I use it for for catching BiF pics, and the odd shot at the moon.
I like the fact that it has a built in filter rotation collar, so as when you put in the CPL you can rotate it. (With the FA* Teles, you have to find a FA*CPL drawer, and they are rarer than hens teeth). The DA560 has a small wheel on the drawer to rotate the CPL.
It's not WR or anything, but to be honest, thats not an issue to me. I do however use a neoprene sleeve right at the mount area, covers the mounting to the camera, goes over the top of the filter drawer, just to keep any dust out.

I like it. I like it a lot. but..

I find, myself using the DFA150-450 more though, due to it's faster focus, weather resistance and the zoom is really much more usable when chasing birds and other wildlife, out and about.

[Bob 256]

I have the Sigma 55-500mm (older non-stabilized version) which I use with my K-1. It works great although I've noticed a bit of vignetting at 500mm at times. Interface-wise, no problems at all.

[termy]

K-1 and Siggy 500/4.5 is a great combo.

Lightweight (relatively speaking, naturally), relatively compact for a 500 prime, doesnt impede your movement much.

Image quality of the Siggy 500 is never in doubt.
(How i wish Sigma still support pentax mount, as the latest evolved variation is the 500/4 Sport)

One possible negative for some is the lack of AF Limiter.
Some prefer to have that, while some dont care about it at all.

[PePe]

I use the big Sigmas (300/2,8 and 500/4,5) mainly for wildlife photography. I find the K-1 II easier to handle with these big lenses than crop bodies. For the same reason I allways have a grip in my APS-C bodies. With the 500 I often have a monopod.

[Watcha]

I have the Sigma 150-500mm F/5-6.3 APO DG OS HSM Lens. To be honest , played with it once in the back garden. Such a big beast, can't be bothered to lug it around.

[angerdan]

I believe Mr. Chalker did the comparison between the Sigma 500 and the Pentax 560.

Here's a comparision:
Pentax 560mm F5.6 vs Sigma 500mm F4.5 Review - Conclusion | PentaxForums.com Reviews

[JimJohnson]

Another instance of not quite the lens you asked about.

At 500mm there is some vignetting on the K-1, but typically not objectionable. It certainly told me I need to clean the sensor - LOL.

The image is of a bald eagle easily 1/3 of a mile away. I think the color and contrast is great, but could be a teeny bit sharper. I used AF and think MF is a better option at this kind of distance. (kind of hard to micro-adjust the focus on a lens this long!) . That might have made a difference. A tripod was used with SR turned off. It is dang hard to hand hold the lens for a subject like this.
ISO 800, 1/750 @ f/16.

[angerdan]

K-1 with Sigma APO DG 170-500mm F5-6.3
Another instance of not quite the lens you asked about.

Thanks, but only the 500mm f4.5 is of interest to me (high resolution/sharpness & fast aperture).

Also the Sigma 170-500mm has a full extended length of 315mm / 12.4", so isn't much shorter than the 500mm 4.5 with its 349mm.
https://assets.calumetphoto.de/2/b/d/d/2bdddb411a184000e7feda5f15669673893d124e_23H1637D4_2.jpg

[PentxOrni]

Hi angerdan, several years ago I owned the combi and used it with diverse TCs, too. The pure use of the 500/4,5 resulted in very sharp and high IQ. Even the speed of the AF was sufficient for me at that time. For extra reach I 1st tried the Sigma 1.4 TC - really bad performance (much less IQ and slow AF acquisition). Then I tried the Kenko 1,5 TC SHQ AF (almost MF but sharp and better IQ). The last option I tried was the Pentax 1,7 TC (prefocussing needed, almost always unsharp shots). The operation together with the TCs was possible when I used my spotting scope as tripod as the weight was unbearable for more than 10 mins. ;-) I have to admit that my main "focus" is on bird photography (BIF and perched ones). The 500/4,5 was sold to a good friend who also was convinced of the high IQ in solo-operation but gave up on it little later, too, as he was also less focused on stationary photography. Now my advice: Try to get a used Pentax 150-400 that has less weight in total, it's more versatile in use and accepts the 1,4 TC, if needed. The IQ of my 1,4 TC at that time was not good, and I only realized it when the gear was sold and I saw perfect shots with that combi more and more... - It's still not a light-weight combo but the IQ sells, especially with the K1. Krgds, Frank