[GeoffMMedia]

I have a dilemma. I am renting the K-1 for a trip to Grand Tetons NP next month. I know I'm also renting the new FA15-30mm to cover the wide stuff and I've got my trusty DA Limited 40mm which is my usual go to lens plus assorted other mid range lenses. But I'm trying to figure out what to rent for a long telephoto. Ideally, I would get the FA 150-450mm but the only place I can find that has that doesn't have the K-1 or the 15-30mm. So, it looks like my options are the Pentax 300mm f/4.0 ED IF DA, the Sigma 150-500mm f/5-6.3 DG OS HSM APO, the Sigma 50-500mm F/4.5-6.3 APO DG OS, and the Sigma 50-500mm f/4.5-6.3 EX DG AF.

I've used the Sigma 150-500 on my K-5 to shoot the Gary Air Show but was underwhelmed by it. It did the job but didn't wow me. I've heard the "Bigmas" are pretty soft on the tight end and I saw the same with the 150-500. I know the 300mm prime would be sharper but I would most likely have to crop to APS-C and I would love the extra range of the Sigmas.

So, the questions are...
1. Is there a big enough IQ difference between the Pentax 300mm and the Sigmas that I should just get the prime and live with the wider cropped image?
2. Has anyone compared the IQ between the EX and the APO OS 50-500 Sigmas? Based on cost alone, I would go with the EX. The camera has sensor SR so I don't need the OS as much and most of what I would be using it for would be things like moose and bears across a meadow. Not birds at close range. So, the faster quieter HSM autofocus doesn't matter so much to me. If I need to focus fast enough for it to make a difference I would have much bigger problems.
3. Has anyone compared the IQ between the 150-500mm and the 50-500mm Sigmas? I have read a few comparisons in a few places but they all have varying opinions on which is sharper overall and where in their range they perform better.
4. Has anyone tried any of these with the K-1? Will the 300mm cover the full frame or will it need to be cropped? Does the pixel shift resolution help with the softness and contrast of the Sigmas?

Thank You

-Geoff

[robthebloke]

I can't talk about the others, but the DA*300 covers the full frame of the K-1 with no problems. https://flic.kr/p/FMP2nM

It's been possibly my most used lens since getting the k-1. I'll admit I need to crop fairly often (mainly due to the size of the tiny birds that inhabit my garden), but it's a great lens on the k-1.

[GeoffMMedia]

Thanks robthebloke

That photo is pretty impressive. I guess the million dollar question is, which looks better, a worse lens at 500mm or a better lens at 300mm but cropped to the same frame?

[traderdrew]

I guess you can't rent the Sigma 500mm F/4.5? I would go for the Pentax 150-450mm partly because there isn't much difference between 450 and 500mm. I've been impressed with that lens in direct sunlight. Images under direct sunlight look as good as they can get to me. I only own the Sigma 500 prime.

I'm curious if the K-1 can improve the image quality of the 150-450 mm under cloudy conditions, simply because larger sensors are more efficient in lower light.

And its not that can get a lot of feather details with the Sigma 500mm F/4.5 wifhout direct sunlight. Sometimes I can

---

Last edited by traderdrew; 05-18-2016 at 10:30 AM.

[wtlwdwgn]

+1 on the D FA 150-450 and add the DA 1.4x TC. And yes, the K-1 handles cloudy, high ISO days very well. Sigma 150-500 + 1.5x TC, ISO 25600.

[robthebloke]

Guys, the OP has ruled out the 150-450 (due to unavailability for hire)

[GeoffMMedia]

I wish I could go for the 150-450mm. If that was available I would just get that without a second thought. But all of the new Pentax stuff is scarce on the rental market. I'm already going to two different places for the body and the 15-30mm lens. Neither of them have the 150-450 and I don't really want to go to a third. Sadly no where has the Sigma 500mm prime either. I agree that would also be a good option.

Thanks for all of the replies

[robthebloke]

I'm curious if the K-1 can improve the image quality of the 150-450 mm under cloudy conditions, simply because larger sensors are more efficient in lower light.

I've attached a 100% crop of a photo taken at ISO 2000, f4.5, 1/200. It has been a really dark and gloomy day today! This is straight out of the K-1 with the DA*300, with no noise reduction, or sharpening applied. On the K-1 it is much easier to get a good looking shot in crappy light compared to my old K-3 (Due mainly to the amount of noise that creeps in, but also the improvements to shake reduction and AF!).

---------- Post added 05-18-16 at 07:31 PM ----------

+1 on the D FA 150-450 and add the DA 1.4x TC.

I was under the impression that the DA 1.4x TC adds in a lot of vignetting because it isn't FF?

[GeoffMMedia]

I've attached a 100% crop of a photo taken at ISO 2000, f4.5, 1/200. It has been a really dark and gloomy day today! This is straight out of the K-1 with the DA*300, with no noise reduction, or sharpening applied. On the K-1 it is much easier to get a good looking shot in crappy light compared to my old K-3 (Due mainly to the amount of noise that creeps in, but also the improvements to shake reduction and AF!).

---------- Post added 05-18-16 at 07:31 PM ----------



I was under the impression that the DA 1.4x TC adds in a lot of vignetting because it isn't FF?

Thanks again Rob

That is really helpful to see a 100% crop with that lens body combination.

[cardinal43]

Hope you find what you want and hope you enjoy shooting the Tetons. Was there in August 2013, and my son and I are heading to Glacier this August - I shoot K20D and he shoots K30. Haven't yet decided what we might rent. Good luck.

[GeoffMMedia]

Stumbled across this this morning and it's pretty much made the decision for me. Sigma Announces Lens Compatibility Issues with K-1 - Third-Party Announcements | PentaxForums.com
It doesn't specifically mention the EX version of the Sigma 50-500 that I was looking at, but I'm pretty sure that's the same form factor as the current version it does mention. It may work or it may not but if there's any compatibility issues with those Sigma product lines I don't want to find out on this trip. Better to go with something that is a little less than ideal but I know the issues going in.

Pentax DA* 300mm f/4 Prime it is.

[SpecialK]

I would get the FA 150-450mm but the only place I can find that has that doesn't have the K-1 or the 15-30mm.

Rent from different place?

... the Sigma 150-500mm f/5-6.3 DG OS HSM APO, the Sigma 50-500mm F/4.5-6.3 APO DG OS, and the Sigma 50-500mm f/4.5-6.3 EX DG AF.

I read in another thread yesterday that the 50-500 and other have an issue fitting on the K-1.

https://www.pentaxforums.com/forums/10-pentax-slr-lens-discussion/320977-sigm...ml#post3641460

[wtlwdwgn]

FYI: LensRentals has the 150-450 in their inventory now.

[GeoffMMedia]

FYI: LensRentals has the 150-450 in their inventory now.

Yeah I was looking at that. But they don't have the FA 15-30mm at all and they don't have the K-1 available until a few days after I would need it. I've already had to get the body from one place and the FA 15-30 lens from another so I'm really trying to avoid getting three items from three vendors.