[channeler]

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Looking for a better quality telephoto zoom. I have a Sigma 70-300 APO Macro DL at the moment which is ok but not outstanding. I've looked at the Sigma 135-400 and the 175-500 but think I'm going to plumb for either the 100-300 or a Bigma. As I want to use it mainly for wildlife if I get the 100-300 I will probably also have to use it with a x1.4 converter some of the time to give me the extra reach. This will probably reduce quality a little though I have seen some outstanding photos using the 100-300 with converter and I'm trying to work out if this lens or the Bigma will deliver better pictures overall. (It's all a bit academic at the moment as Sigma Pentax Fit lenses are in very short supply here in England. Hopefully as we get into the New Year stocks will improve.)

Any views?

Paul

PS: Another factor that I may need to consider is the Bigma's weight. Taking things on planes in hand luggage has become more of an issue in the UK due to item/weight restrictions as a result of increased security. (We always have to carry a laptop with us, which used to be allowed as a separate item but no longer).

[Chako]

Well the 100-300 is 52.2 oz (1.5Kg), and the 50-500 is 64.9 oz (1.8Kg). That is not that great of a difference in weight.

In my neck of the woods, the Bigma is around 100 cheaper.

I am not including the cropping factor in this example. If you use a 2x teleconverter on the 100-300 f/4, you can get a 200-600mm f/8 lens (you lose two stops of light). If you use a 1.4x teleconverter, you can get a 140-420mm f/5.6 lens (you only lose one stop of light).

The Bigma can get you to 500mm with no need for a teleconverter at f/6.3. Plus you can get a slow but equally handy 50mm f/4 at the low end.

I have the Bigma and like it quite a lot (Canon Mount). I can see going the other way if the lens was an f/2.8, but then it would be more expensive, and a great deal heavier then these other two lenses.

Basically its up to you to decide which lens you plan on using more often. If you are planning on using 400-500mm more, then I would suggest getting the Bigma. This way, you don't have to fiddle with an extra teleconverter. But that is just my opinion. On the other hand, you can get an f/5.6 420mm. It all depends on what your planning to use this for. Either or. Sorry I couldn't be more help to you.

[m8o]

I was very close to getting the 100-300mm f/4 but settled on the next step up for speed and performance I'd have with TCs. The way I always look at this question, is will you need the speed? Will you shoot in dim lightng conditions, or drizzly weather, at 100 - 300mm, and use it wide open? The Bigma isn't f/4 for long; and it is much slower at 300mm. If you need lower light shooting the 100-300/4 gives you better usability in dimmer lighting conditions; near similar reach and f-stop specs as the Bigma at the longer end with say the Pentax 1.7x TC. I would put money on the 100-300mm f/4 performing about the same as the Bigma resolution and contrast wise with the 1.4x TC ; performs better with no TC, all/both at the expense of reach. If you aren't one for swapping TCs based on conditions, the Bigma can't be beat for convenience and the results it gives even with the compromises it must have given the 10x zoom range.

[Peter Zack]

Paul, at the time I couldn't afford M80's solution (300mm f2.8) so ater debating these same 2 lenses, I opted for the Bigma. Absolutely no regrets. A few reasons:
A) 1 lens to deal with with a broader range.
B) no TC to carry and fiddle with in the field to get longer reach
C) TC won't degrade image quality ( and even the best ones do to some degree).
D) (1.4 Sigma) TC + 100-300mm is considerably more money for very litte benifit.

So if you find that 300mm is not enough from your current lens. Then I'd recommend the Bigma is the better lens for the subject you want to shoot.

Note there's a Bigma in the Marketplace right now at a very good price.

[Peter Zack]

BTW consider a monopod for either. you will not regret it.

[GaryML]

Looking for a better quality telephoto zoom. I have a Sigma 70-300 APO Macro DL at the moment which is ok but not outstanding. I've looked at the Sigma 135-400 and the 175-500 but think I'm going to plumb for either the 100-300 or a Bigma. As I want to use it mainly for wildlife if I get the 100-300 I will probably also have to use it with a x1.4 converter some of the time to give me the extra reach. This will probably reduce quality a little though I have seen some outstanding photos using the 100-300 with converter and I'm trying to work out if this lens or the Bigma will deliver better pictures overall. (It's all a bit academic at the moment as Sigma Pentax Fit lenses are in very short supply here in England. Hopefully as we get into the New Year stocks will improve.)

Any views?

I had the Sigma 100-400 f4 EX DG lens with the matching 1.4X EX DG teleconverter. The lens is a great performer and gives sharp, contrasty images even wide open. Stop down a stop or two and it is fantastic. I selected it over the Bigma for the wider aperture at 300mm. For sports/action use I wanted to blur the background as much as possible, get a fast shutter speed, and a brighter viewfinder. The lens met my expectations optically, but the AF speed was a bit too slow for my needs. The AF speed is worse with the converter. The HSM version (not available for Pentax) would have been perfect. For wildlife use, I think the AF speed will be fine.

I haven't used the Bigma so I can't offer a direct comparison. I went with the 100-300 f4 for the reasons mentioned above, plus the internal zooming and focusing results in better handling (for me at least).

And I agree with the suggestion to get a monopod or tripod. Holding that heavy lens gets tiring after a while. The tripod foot is pretty good, but it does interfere with the zoom ring a bit.

[RussellW]

I have had the Bigma for sometime, and have mostly used it for motorsport with great results. I can't remember the reason at the time for buying it but it has been a winner for me.

[channeler]

Thanks for everyone's input on this. It is very helpful and has given me food for thought. Still a bit undecided between the two. I do seem to find myself shooting quite a bit in wooded areas where the constant f4 of the 100-300 may be a help. The images I've seen produced by the 100-300 seem to have a little more colour/contrast/punch to them than the Bigma, but once you add a TC perhaps the image quality between the two lenses is going to be comparable. Going to just have to take the plunge at some point. The other factor is availability. Sigma said stocks of Bigmas with Pentax mounts would be shipping into England just after Christmas but couldn't give a date for more 100-300s.

I already have a tripod but a monopod would probably be a good investment as people have said. Are there any monopods people would particularly recommend?

Paul

[m8o]

The one I have:
Bogen / Manfrotto | 685B NeoTec Monopod Deluxe | 685B | B&H

- can be raised and lowered with one hand via a handgrip lever
- has a rubber foot or spike (just watch you don't loose the rubber foot in the woods; B&H clips them onto the monopod bottom shaft in their showroom)
- handles loadw of weight and never slips
- can double as a walking stick (take off the rubber foot 1st)

[Peter Zack]

I have this one. Mine comes with a slightly different head and a shoulder bag. Big and sturdy. I've never had an issue with the foot (similar to M80's design). I just screw the foot up to expose the spike when outdoors.

DYNATRAN PROFESSIONAL MONOPOD AT-1016 - eBay (item 360011809035 end time Feb-06-08 06:19:10 PST)

[christinelandon]

Paul, I've used a Slik Pro Pod 381CF for the past three years and love it. Currently, it's got a Slik SBH-120 small ballhead topped by a Kirk 1.75 inch Arca-Swiss-style quick release clamp to fit the camera plates on my K10D and Spotmatic. The combo is light, stiff, quick to adjust, and offers lots of height when I need it on steep or rough terrain. Doesn't double as a hiking staff, though. On the other hand, now that Pentax is owned by Hoya, it's "all in the family" except for the Kirk plates!

[channeler]

Thanks for that Christine. Will look at the monopods when I decide on the lens. Still agonising a bit between the Bigma and the Sigma 100-300. One guy I came across sold the Bigma to replace it with the 100-300 and reckons he gets better IQ even with a x1.4 TC. Will have to take the plunge soon.

Paul

[christinelandon]

Paul, I can sympathize with your most enjoyable LBA agonies...I'm mulling over the choice between Sigma's 100-300mm and their 135-400mm at present. Waiting to see how much Pentax plans to ask for the forthcoming DA* tele primes, too! Oh, my smoldering bank balance!

[Peter Zack]

Paul, You may want to check out the following thread Home near the end, Javier has just gotten the Sigma 100-300mm. It would appear to match the Pentax DA*300mm and works well with the 1.4xTC. I just sold my Bigma for an FA*300mm and with the Tamron 1.4 (420mm) and Pentax AF1.7TC (510mm) it works very well with great IQ and focus speed.

So forget what I said some time ago, I think the best combo would be either of these 2 lenses with the Tamron TC. The 100-300 sells for less than the Bigma (at new prices) and the 1.4 is about $130-150 used.

Well the 100-300 is 52.2 oz (1.5Kg), and the 50-500 is 64.9 oz (1.8Kg). That is not that great of a difference in weight.

Althought this is true, it can be also misleading. The bigma extend when zoomed big time and the weight of the front element is high, making it more difficult to handheld. Due to the heaviness of the front elements the zoom tends to creep a lot when the lens is not horizontal, which makes the things less ergonomic even if you are using a tripod/monopod. Besides that, I found the lens fantastic.