[dakotapix]

After using a Pentax long telephoto for many years, it feels like it might be time to look at possibly upgrading equipment. The use would be primarily for birding and general wildlife photography. Size and price would be minor factors in the choice, with sharpness being the main criterion. Bokeh would be a tiebreaker, but secondary to sharpness.

For better or worse, I'd like to stay with Pentax, and am interested in opinions of the following, particularly how one might compare to another:

- A* 600mm f/5.6
- FA* 600mm f4
- DA 560mm f/5.6
- D FA 150-450mm (yes, one of these things is not like the others)

I've found bits and pieces through the forum dealing with comparisons, but nothing dedicated to the subject as laid out here. If such a thread exists, I'd love to be pointed to it.

All opinions (and evidence) are certainly welcome, but I'd be especially interested in hearing from folks that have personal experience with two or more of these lenses. Thanks!

[VoiceOfReason]

The DFA 150-450 is sharp even wide open and even with the 1.4tc. That being said I'd love to have the FA* 600 f/4 as a supplemental lens.

[dakotapix]

The DFA 150-450 is sharp even wide open and even with the 1.4tc. That being said I'd love to have the FA* 600 f/4 as a supplemental lens.

My thought was that if the 150-450 was sharp enough, I could crop to the same magnification. Not as effective on a K-5/K-1, but maybe a possibility with the K-3.

From your signature, I can assume you're referring to the Pentax HD 1.4 AW teleconverter?

[Venom3300]

The 150-450 is the most convenient choice. The 600/4 is going to give the best results.

[dakotapix]

The 150-450 is the most convenient choice. The 600/4 is going to give the best results.

I have to admit that the FA* 600 has been one of the top two lenses on my wish list for a very long time. But now that the remote possibility of a purchase is coming closer to being almost a distant possibility, I begin to wonder if it might make sense to go with newer technology.

I've been very impressed with some of the images on the forum from the 560, and while there's some very nice FA* 600 images on the PPG, I'm not sure they have the same pop.

[VoiceOfReason]

My thought was that if the 150-450 was sharp enough, I could crop to the same magnification. Not as effective on a K-5/K-1, but maybe a possibility with the K-3.

From your signature, I can assume you're referring to the Pentax HD 1.4 AW teleconverter?

Yes, and it is absolutely wonderful with the 150-450 even at 450mm on the K3, not so much on the K1 because you have to crop due to severe vignetting. With careful cropping you can still end up with a larger image than simply letting the camera crop though.

[snostorm]

Hi dakotapix,

For me, a decision between the four lenses listed is pretty much a no brainer, but that's me. Although the A* 600/5.6 and DA* 560 are realistically usable from a portability standpoint for me, the MFD of @ 15 feet makes them unusable for what I like to shoot. The FA* 600/4 is obviously an exemplary lens, as is the FA* 250-600/5.6, but the 13+ lb weight would not be manageable for me, and the 600's 13 foot MFD would be an additional deal breaker. I like to shoot handheld and usually from 8-15 feet optimally. . .

The DFA 150-450, though a bit short, is light (4.4 lbs) enough to handhold effectively and focuses down to @ 6 feet. It's sharp even wide open and fast focusing. It's not my favorite, which remains and FA* 300/4.5 + F 1.7x AFA, which gives me 2+ lb 510mm f7.7 with built in focus limiter and very quick AF lock (albeit with some AF limitations), but the DFA 150-450 gives me a quality WR alternative if conditions dictate.

Scott

[dakotapix]

Yes, and it is absolutely wonderful with the 150-450 even at 450mm on the K3, not so much on the K1 because you have to crop due to severe vignetting. With careful cropping you can still end up with a larger image than simply letting the camera crop though.

Good to know. Thanks!

---------- Post added 09-02-16 at 04:41 PM ----------

Hi dakotapix,

For me, a decision between the four lenses listed is pretty much a no brainer…

You make a good point about the minimum focus distance--it's something I bump into from time to time as well. That being said, it's not make/break for me.

I concur that the FA*300 is stellar, but have not had as much luck using it with the 1.7 TC as you have. I have wondered if I have a decent copy of the TC.

[pacerr]

One of the characteristics of extension tubes is to shorten the minimum focusing distance. Reading this thread it just occurred to me that in the past I've used 10-25mm of extension to reduce MFD when needed. Of course you loose AE/AF data contacts unless you gut a PKA TC tube and those I've seen are all at least 24mm or longer.

For example, in one case I intentionally added 9 mm of extension while converting a Tamron OM 300/5.6 lens to PK mount. That reduced the MFD by approximately 30-percent and the max distance to about 70 ft -- perfect for the backyard-bird-shooter use I had in mind.

Some where 'round here I've got a gutted PKA 2X TC I could try with a DA*300 if anyone's curious.

[mikeSF]

i have the DFA150-450 and i would not say it is sharp wide open. It improves (at the long end) with some stopping down. I find it a versatile solution and I am happy, but given the choice of the FA*600 or A*600, I would take them instead without question, lol.
Good luck deciding.

[biz-engineer]

Yes, and it is absolutely wonderful with the 150-450 even at 450mm on the K3, not so much on the K1 because you have to crop due to severe vignetting

Really. I do not get any noticeable vignetting with DFA150-450 on K1 at any focal length.

i have the DFA150-450 and i would not say it is sharp wide open. It improves (at the long end) with some stopping down.

I'd say the same.

[dakotapix]

Really. I do not get any noticeable vignetting with DFA150-450 on K1 at any focal length.

I think VoiceOfReason is referring to the TC.

---------- Post added 09-02-16 at 07:19 PM ----------

One of the characteristics of extension tubes is to shorten the minimum focusing distance. Reading this thread it just occurred to me that in the past I've used 10-25mm of extension to reduce MFD when needed. Of course you loose AE/AF data contacts unless you gut a PKA TC tube and those I've seen are all at least 24mm or longer.

Good point. Something definitely to keep in mind.

---------- Post added 09-02-16 at 07:23 PM ----------

i have the DFA150-450 and i would not say it is sharp wide open. It improves (at the long end) with some stopping down. I find it a versatile solution and I am happy, but given the choice of the FA*600 or A*600, I would take them instead without question, lol.
Good luck deciding.

Good to know. The thought of having to stop down is not a disqualifier. Thanks for the well wishes!

---------- Post added 09-02-16 at 07:24 PM ----------

I'd say the same.

Thanks. The additional experience is appreciated.

[UncleVanya]

Really. I do not get any noticeable vignetting with DFA150-450 on K1 at any focal length.

I think he was talking about the use of that lens with the HD DA 1.4X attached. Granted I also think 450mm was really 630mm (1.4*450).

[VoiceOfReason]

Yep, I was talking about with the 1.4tc. Without it there is no vignetting on the K1.

[cleaverx]

I would go for FA *600mm/f4...no match in sharpness for prime lens. DA 560mm f/5.6 is fully compatible with K-1 in "Full Frame Mode",,there should special full-frame lens correction profile in K-1 for this lens.