[zzeitg]

FA* 250-600 or DA 560? Which one would you buy and why? Pros and cons?

[rawr]

The DFA 150-450.

[boriscleto]

The 560 is AW, DC AF, has modern coatings, and is more than 2 kilograms lighter...

At this point I don't think the 150-450 is worth the price over the very nice 150-500 I already own...

[bertwert]

Which one would you buy and why?

Neither, I couldn't afford them.
If someone was giving me one I'd choose the 560 (or maybe FA* 600/4).

[jatrax]

Would love to see a comparison between dfa 150-450 plus 1.4 tc and the 250-600

[Scorpio71GR]

That is a tough one and I think it come down to more about shooting style. The FA*250-600 is simply to heavy to shoot handheld. You will need a heavy duty tripod and mount. The flexibility of being a zoom plus the minimum focus distance of 10 feet (3meters) is definitely a plus. If you are willing to wait to find a nice used one which may take awhile. For me this is a lens that is just out of my price range however I sure would love to get to use one once. Internal focus and internal zoom on such a focal range is really something. The 560 can be purchased new with a warranty. DC motor plus weather sealing is a plus for sure. From what I have seen of the HD coating it really does cut down on flare. The 560 is almost half of the 250-600 in weight so I would be able to take it more places. If I had a place we're I could set up all day in one spot I, and could afford it, I would go for the 250-600. I however do not have that option, so I need something more portable like the 560.

If I were to get a 500mm prime I would most likely get the Sigma 500 f4.5. It is full frame ready, f4.5, and about the same weight as the 560. I know it is not WR but that has never stopped me in the last 30 years. However my next upgrade will most likely be the 150-450. It is more in my price range and not so heavy to burden me when hiking.

[VoiceOfReason]

I'd love to get the FA* 250-600, but it is definitely out of my price range. I own the 150-450 and the 1.4 tc. It gives me 630mm at f/8.

[Lowell Goudge]

I think the question depends on what you already have.

For me, I would take the 560/5.6 BUT that is because I shoot multiple bodies, and already have a sigma APO70-200/2.8 EX (non DG non macro) which is exceedingly sharp even when used with the sigma 1.4x and 2x TCs. So, I have the range below 560mm covered. I don't see the extra 40mm that big a difference, especially on APSC

If you didn't have a reliable high quality option to 300+ mm I might think about the FA zoom, but I still like the 2 body option when dealing with one lens that is in all likelyhood tripod bound

[northcoastgreg]

I'd go with the DFA 560 for the lighter weight and more modern optics/coatings.

[zzeitg]

Would love to see a comparison between dfa 150-450 plus 1.4 tc and the 250-600

Me too!

Internal focus and internal zoom on such a focal range is really something.

I think so. That's a very nice lens design.

I own the 150-450 and the 1.4 tc. It gives me 630mm at f/8.

How does AF work in this case? (I guess the 1.4x TC is recommended only for lenses up to f4, while in this case it's f5.6.)

I think the question depends on what you already have.

Well, not so much when it comes to long focal length. I currently use DA*300 (in combo with 1.4x TC most of the time) and also Sigma 150-500.
(I also have DA*200 and FA* 80-200, but these are too short for birding anyway.)
Couple of times I tried to combine 1.4x TC with this Sigma, but AF is hunting most of the time unless the light conditions are really excellent.




Speaking about both lenses (FA*250-600 and DA560) - can they both be used with 1.4x TC?

[VoiceOfReason]

How does AF work in this case? (I guess the 1.4x TC is recommended only for lenses up to f4, while in this case it's f5.6.)

It works perfectly in my experience.

[Lowell Goudge]

How does AF work in this case? (I guess the 1.4x TC is recommended only for lenses up to f4, while in this case it's f5



Speaking about both lenses (FA*250-600 and DA560) - can they both be used with 1.4x TC?

This issue comes up from time to time , specifically native minimum lens speed and use of teleconverters.

I find Pentax is very conservative when they state maximum aperture requirements.

In 1991, I bought the SMC F 1.7x AF converter. All the data sheets stated maximum aperture F2.8 or faster for AF to work. Even back then, my PZ1 could focus in all reasonable light conditions (night but not pitch black) on my K300/4.

Today many people use this on F4.5 lenses with newer DSLRs

It used to be for functioning AF we needed native aperture considering the losses in the TC attached ofnF6.9, today I believe that is at least F8 if not better.

[zzeitg]

Anther aspect I'm thinking about is AF system. FA 250-600 is screw drive, DA560 is SDM only. Are there some SDM troubles to be expected?

[Scorpio71GR]

The 560 uses the newer DC motor. I have never heard of a failure with the DC motor. This is the same motor used in thec18-135, 16-85, and the 150-450. It is extremely fast and reliable in my opinion.

[angerdan]

Anther aspect I'm thinking about is AF system. FA 250-600 is screw drive, DA560 is SDM only. Are there some SDM troubles to be expected?

DA 560mm is DC - not SDM.

Advantages of the DA 560mm:

• available new (means replacements parts still available)
• much! cheaper
• less weight
• easier af limiter
• WR
• QS

Advantages of the FA* 250-600mm:

• Variable focal length
• less vignetting
• PZ