[arsenal_emyrates]

let's not think in terms of money but in terms of IQ and AF .
so sigma 150-500 or pentax da 60-250 + teleconverter ?

[RonHendriks1966]

Just a reminder since I did a little review on the 60-250.

https://www.pentaxforums.com/forums/pentax-slr-lens-discussion/143968-da%2A60...ml#post1510577

I'm not a big fan for TC, but if you have a good one (not the cheapo once) only f1.4 would be applied in my mind. So you will limit yourself to 84-350mm/f5.6 wich is a little short for birds.

[Digitalis]

I'm not a big fan for TC

Me niether, if you want a to buy a quality DA* lens and reduce it to mediocrity with a TC then by all means get the sigma 150-500mm - it will give you the same experience.

[arsenal_emyrates]

i was just asking in case of the need of a longer reach ..why are you saying that a TC will bring the DA lens to mediocrity ? from what i have read TC are used all the time ... are they not quality TC on the market that don't bring a DA lens to mediocrity ?

[Digitalis]

why are you saying that a TC will bring the DA lens to mediocrity ? from what i have read TC are used all the time

Teleconverters both 1.4X and 2X TC's are only appropriate for fast prime lenses,e.g 400mm f/2.8 lenses. Using them on zoom lenses only makes a zoom lens perform substantially worse, primes can handle TC's because of the fact that image quality from a prime lens even at their widest aperture tends to be at an extremely high level.

[dgaies]

i was just asking in case of the need of a longer reach ..why are you saying that a TC will bring the DA lens to mediocrity ? from what i have read TC are used all the time ... are they not quality TC on the market that don't bring a DA lens to mediocrity ?

I don't beleieve TC's are used very often with the DA*60-250. For one thing, there isn't a TC that will retain a fully usable level of AF with the DA*60-250. The Tamron 1.4x Pz-AF works ok in terms of AF, but it's far from perfect. The 1.7x AF-A works fairly well, but it's not fully automatic and you have to pre-focus and then engage the AF. Bottom line, there really aren't any good AF options for the DA* lenses in terms of TCs.

[dgaies]

Teleconverters both 1.4X and 2X TC's are only appropriate for fast prime lenses,e.g 400mm f/2.8 lenses. Using them on zoom lenses only makes a zoom lens perform substantially worse, primes can handle TC's because of the fact that image quality from a prime lens even at their widest aperture tends to be at an extremely high level.

I tend to agree here as well. The only lens I own that I would be tempted to use a TC with is my DA*300/4. I've tried it with both the Tamron 1.4x and Pentax 1.7x AF-A and felt the results were pretty decent.

[nater]

Teleconverters both 1.4X and 2X TC's are only appropriate for fast prime lenses,e.g 400mm f/2.8 lenses. Using them on zoom lenses only makes a zoom lens perform substantially worse, primes can handle TC's because of the fact that image quality from a prime lens even at their widest aperture tends to be at an extremely high level.

While generally good advice, I'd like to add that the Tamron 70-200mm f/2.8 + Kenko 1.5x teleconverter works well together. I've been very happy with the results.

[dgaies]

While generally good advice, I'd like to add that the Tamron 70-200mm f/2.8 + Kenko 1.5x teleconverter works well together. I've been very happy with the results.

That's true. I was thinking only about the DA* zooms I had tried with TCs, but the Tamron 70-200/2.8 (I used to own) actually held up fairly well when I tried it with a TC (out of curiosity). I also found the AF to be fairly decent when paired with the Tamron 1.4x (which is basically the same as the Kenko 1.5x in terms of it's IQ and effect on AF).

[Digitalis]

I'd like to add that the Tamron 70-200mm f/2.8 + Kenko 1.5x teleconverter works well together. I've been very happy with the results

though you would get even better image quality from a sigma 100-300mm f/4 APO EX DG

[dgaies]

though you would get even better image quality from a sigma 100-300mm f/4 APO EX DG

Without a doubt, the 100-300/4 will exceed the Tamron 70-200/2.8+1.4x in terms of IQ.

Then again, the Tamron will have a far easier time shooting between 70-100mm and at f/2.8

[Digitalis]

Tamron will have a far easier time shooting between 70-100mm and at f/2.8

that's what I use the FA77 f/1.8 limited and 100mm f/2.8 Macro lenses for - and both of those lenses run rings around the tamron when it comes to Image quality at f/2.8

[dgaies]

that's what I use the FA77 f/1.8 limited and 100mm f/2.8 Macro lenses for - and both of those lenses run rings around the tamron when it comes to Image quality at f/2.8

No argument here. I have the 77 and 100WR (and the FA*85 in between) and they all beat the Tamron 70-200/2.8 in terms of IQ at f/2.8.

However, if a person was trying choosing between the 70-200/2.8+1.4x and a 100-300/4 and didn't own a nice prime in the 70-100mm range, then the ability to shoot between 70-100mm @ f/2.8 might be relevant.

[nater]

However, if a person was trying choosing between the 70-200/2.8+1.4x and a 100-300/4 and didn't own a nice prime in the 70-100mm range, then the ability to shoot between 70-100mm @ f/2.8 might be relevant.

Bingo, you've described me.

I agree that a kind of ideal would be a selection of primes, a 70-200mm f/2.8 and a 100-300mm f/4, but I don't shoot enough at the long end to justify the expense, and also the potential complexity of carrying two bigger telephoto zoom lenses.

The 70-200mm works well for people pictures in a way that the 100-300mm just wouldn't, so it ends up being a more versatile lens for me I think. Also, the Sigma 100-300mm f/4 was out of stock (now out of production?) when I bought my Tamron 70-200mm f/2.8, and the Tamron was a good bit cheaper as well. In fact, I was able to buy a used Tokina 80-400mm f/4.5-5.6 and the Kenko 1.5x teleconverter for the difference in cost.

[Mike.P®]

I got hold of a Kenko 1.5x teleconverter the other day just to see how it performed with my DA* 200mm and DA* 60-250mm.

Here is a quick test shot with the 60-250mm and TC hand held @ 250mm (375mm) .. I didn't think it was actually that bad.