[SirBismuth]

Hi All,

I am looking to replace my Pentax FA SMC 4.5-5.6 100-300, as I am not happy with it's performance at the 300 end (too soft for my liking, although I have got one or two nice shots with the 2x tele and MF (and some darn good stabilization)).

The two lenses I am looking at are as follows:

1. Sigma 70-300mm f/4-5.6 APO DG Macro

2. Pentax SMC DA 55-300mm F4-5.8 ED

I have read the reviews on PF, and the Sigma seems to be a bit soft at the long end, but not so much the Pentax lens as long as it's wide open (suites me).

If there is a better lens similar to these, I can consider it, even if I have to save a bit (will have to in any case if I go for the Pentax). I still have my eye on a Tamron 70-200 2.8, but want something a bit longer as well.

B

[Ash]

The 55-300 is both excellent in IQ as well as affordable. Its compact size makes it very portable too.

[Kerrowdown]

If you want better IQ at the long end, have you considered a prime 300mm?

I'm not sure that the two lenses your looking at, will offer you all that much better than the one you have. They both have an even longer zoom range to deal with over your current 100-300. Zooms by the nature of their design generally have to comprise somewhere within their range.

[GibbyTheMole]

The Pentax 55-300 should be quite a bit better at the long end than the one you have now. I can tell you my copy is very sharp from about 80-300mm. It's one of the relatively few zooms that's sharp all the way out to the maximum focal length.

[Louicio]

The silver FA 100-300 4.7-5.8 is vastly better than the version you have. Consider giving it a try if you are on a tight budget.

[Sandy Hancock]

I would also suggest the DA55-300. I sold mine, but despite having better lenses to cover the range, I still miss it on some levels.

As Ash said – it's compact. light, fairly cheap and has good resolution all the way to 300. Sure, it's not super fast but you can't have everything.

[VisualDarkness]

I've seen some wonderful shots with the 55-300, it even holds up when it comes to sharpness when mounted on a Q. If you are after real quality on the long end something like a good prime or a longer tele like a Sigma 150-500 as avoiding the extreme ends of a zoom most often improves sharpness.

[boriscleto]

I have said a number of times that they can have my DA L 55-300 when they pry it from my cold dead hands...or Pentax releases a WR version.

[bobpur]

I have tried multitudes of something to 300mm zooms and none have been exceptional at 300, sorry even the Pentax Da is not as good as my
old Adaptall 300.
What I did find is a very good zoom like your 70-200 2.8 with a quality 1.4X works as well or better than the lower cost to 300mm zooms.
Will get you a constant 100-300mm f4 and the fast 70-200 2.8 when you want it and takes up little space.

[KevinR]

There is no one answer to this one because it comes down to your priorities and pocket. Some thoughts and local (new) prices from cameraworld site below.

The DA 55-300 (R4.4k) is much better (imho) than Sigma 70-300 DG APO (R2.5), but is not massively better. There is also the Tamron 70-300 DI which is quite sharp, but I would avoid this for SA as it blooms Purple Fringe in bright sun conditions. To really jump up in IQ you might need to look at a DA*300 prime (R15k) or one of the Sigma/Tamron 70-200 f/2.8 (R12-16k). The silver 100-300 f/4.7-5.8 is reportedly better (as noted by @Louicio), but that might not be a big enough step. I don't think it is better than the DA55-300.

You also refer to using the 100-300 with a 2x converter. That implies you might be after a bit more range...? In that end you get stuck between the Sigma Bigma zooms (R12-17k) and some really expensive Sigma/Pentax primes (R50-70k).

Have a look at olx for an FA300 and 1.4x TC in kzn which might also be an option to the DA300.

[tibbitts]

The 55-300 has very inconsistent performance. I've only tried one with very good performance across the field at 300mm - and it really is very, very good. Amazingly good for the price. That copy at 55mm on the left side... not so amazing. Other copies I've tried are very, very good across the field at 55mm - but not across the field at 300mm. It could take you dozens of tries to find a really good copy, so just buy where you can return easily.

Paul

[SirBismuth]

I am actually looking for something longer than 300, but that has to wait for now. After mulling it over, am not going to get the 55-500 (?) APO (non-DG) from Sigma, rather wait a bit and get the DG version.

I don't have the 70-200 2.8 YET, currently on my LBA wishlist. By the time I do get it, or something similar, will look at a decent 1.4x TC as well, possibly.

From what I've read here, and on the Net, it would appear if I want the better IQ, I would need to go the prime route. When I was photographing in a nature reserve this weekend, really couldn't get away with less than 300 for most shots, a few times really need something longer (300-500 or so), otherwise birds are just too small. On the plus side, that does force me to be a bit more creative when composing the shot.

My 100-300 doesn't have bad IQ generally, but going over +/-250, it is not so nice, and I was using it over 250 for most of my shots.

All things considered, I think I will have to look at primes in the 300+ range. Unfortunately, that won't happen overnight, so will have to start saving.

I can't even rent these longer lenses in South Africa, unless I had a Canikon.... bleh!

B

[bullitt_60]

I've owned both and the DA 55-300 is better than the Sigma at every focal length and any aperture. When stopped down, it compares well to the Tamron 70-200. It is also lighter and more compact. Also, the front element on the Sigma rotates during focusing.