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Joe Davis
01-20-2007, 07:23 PM
Can somebody help a newbie out? I am looking for another lens for my K10D. I shoot a lot of indoor sports and am trying to use less flash. I was told I need to get a good low light lens. Possibly a f2.8. Is that what I need. I was looking at this one from Sigma:

http://www.bhphotovideo.com/bnh/controller/home?O=Search&A=details&Q=&sku=384940&is=USA&addedTroughType=search

Thanks

jcon
01-21-2007, 09:30 AM
The version for Nikon is pretty popular and is a good low light sports lens. I dont know how the Pentax version performs but I would guess it would work good. You could go to PBase.com and check out photos taken with that exact set-up.

Polytrope
01-22-2007, 09:57 PM
Can somebody help a newbie out? I am looking for another lens for my K10D. I shoot a lot of indoor sports and am trying to use less flash. I was told I need to get a good low light lens. Possibly a f2.8. Is that what I need. I was looking at this one from Sigma:

http://www.bhphotovideo.com/bnh/controller/home?O=Search&A=details&Q=&sku=384940&is=USA&addedTroughType=search

Thanks

Joe,

I have recently answered just this question for myself by acquiring the Sigma 28-70 F2.8 DG EX lens. The constant max f/2.8 aperture gives results that are a big improvement over what I got from my otherwise very satisfactory Tamron 18-200 3.5-6.something zoom. Here is a link to one of the photos I took last weekend (http://picasaweb.google.com/wmb.porter/20070120Basketball/photo#5022718696872862706) with this new lens. (The whole gallery is shot with that lens. The white balance problems are not the lens's fault, by the way, but mine.)

If you need more telephoto than I did, then the lens you linked to might be just the ticket.

Will

Joe Davis
01-23-2007, 10:14 AM
Thanks for the replies.

So, it is my understanding that the lens will remain at f2.8 no matter if it is 70mm or zoomed in to 200mm?

I have a Sigma 50mm f2.8 macro lens that takes great shots. So I was wondering about the telephoto and the ability to shoot at f2.8 when shooting at 200mm.

Thanks again.

jcon
01-23-2007, 12:03 PM
Yep, thats correct, a constant 2.8 means you can shoot with an aperture of 2.8 throughtout the entire zoom range.

SpecialK
01-24-2007, 09:55 PM
Don't forget a tripod, or at least a monopod for that big one..

rfortson
01-30-2007, 09:15 PM
If you don't mind manual focus, you can get 135mm f/2.5 or f/2.8 primes all day for ~$50 on ebay. In the middle of your 70-200 range, but waaaaaaaay less expensive.

Just a thought....

Russ

CptOfGondor
02-05-2007, 07:22 AM
rfortson's right. Lenses like the SMC Pentax M 135mm f3.5 are cheap (under $100) and very sharp. You can also look into a 200mm prime as well.

That is the genius of the K Mount. It retains a long range of backwards compatibility you don't really see in other lens mount offerings. Sigma lenses don't really design their lenses with Pentax in mind. Sigma really only focuses on Canon and Nikon mount offerings. The Kmount rank a low fifth on their priorities. (SA Mount being 3rd and 4/3rd 4th).

If you like sports, remember that the difference between a 2.8 and a 3.5 is relatively minimal. If you need flash at f3.5, you'll most likely need flash for 2.8. Since you already have a flash head, try a diffuser cap? or bounce screen and get up as close to the edge of the field as possible.

Polytrope
02-05-2007, 02:48 PM
Don't forget a tripod, or at least a monopod for that big one..

This is no doubt good advice, but I don't follow it, and for reasons that also seem valid. One of the main reasons to get the big aperture is so that you can shoot with a faster shutter, and if the shutter is fast enough - say, over 1/250s - using a K100D or K10D, you may be able to get away without the tripod or monopod. I have tried both tripod and monopod at my daughter's basketball games. Just too much trouble. Same problem I have using a tripod/monopod when shooting small birds - the subject moves around a lot, and I find it nearly impossible to move the camera around on the tripod or monopod and keep the subject in view. For basketball games, I've been given the advice to focus on the area under the basket and then wait for the players to get in there. So far I have not found that an effective strategy. I miss too many interesting shots elsewhere on the court.

Will

Polytrope
02-05-2007, 02:55 PM
rfortson's right. Lenses like the SMC Pentax M 135mm f3.5 are cheap (under $100) and very sharp.

Yes, but also remember that auto-focus is really useful when things are moving fast.



If you like sports, remember that the difference between a 2.8 and a 3.5 is relatively minimal.

Well, the difference between f/2.8 and f/3.5 is not very big, all things being equal. But if the lens doesn't have a fixed aperture, and you use the zoom at all, you may be looking at a much more significant difference than this. My Sigma 28-70 f/2.8 replaces the Tamron 18-200 f/3.5-6.3 that I started with. I was able to get f/3.5 only at the very wide end of the zoom. Somewhere around focal length = 40mm the aperture jumped another notch. At 70mm, the difference between the two lenses was quite significant.

I would like to buy the Pentax 50mm auto-focus f/1.4 but it's apparently out of stock everywhere. I have a Pentax M (manual focus) 50mm f/1.4, and it handles the light inside the gymns pretty well. But I really miss the auto-focus. When I used it, I got a couple very satisfying shots - and a lot of shots that were a little out of focus, enough so to be unusable. The shots I take with the Sigma 28-70 f/2.8 tend to be a bit dark and need some post-processing, which is regrettable; but most of them are in focus.



If you need flash at f3.5, you'll most likely need flash for 2.8.

I'm able to do all right with my fixed f/2.8 and no flash - and in any case, flash is prohibited so it's not an option.

Will

Joe Davis
02-06-2007, 12:11 PM
Thanks again for the replies guys. You give me a lot to think about.

And as far as the monopod, I agree when it comes to basketball games. There is just too much action coming at you too fast to use it. I do use a monopod with my 170-500 lens when shooting football, baseball and softball. Although I probably don't need it because I use at least 1/500 shutter speed but it is nice to have the lens on a monopd so you can sort of relax in between pitches if need be.

Thanks again.

BTW, does anybody have a link to a page that breaks down all the lens mount types? K, KA, etc.

CptOfGondor
02-06-2007, 06:36 PM
http://kmp.bdimitrov.de/technology/summary/index.html

jcon
02-06-2007, 07:28 PM
Joe, I think youre on the right track in what you are looking for. You have gotten some good advice in this thread, however, you need ATLEAST 2.8 for indoor sports 3.5 just wont cut it, bottom line.

I think you will find that Sigma you linked to in your initial post will suit your needs just fine.

Fixed focal length lenses can be great for low light, but for some events, they are too limiting in range.

Again, make sure you get ATLEAST 2.8 glass, if you can get faster, wonderful!

Good luck to you.