300mm+ Lens for K20D

[Cage]

Hi fellow Pentaxians

I've decided to bite the bullet and look for an auto focus lens for birding
.
In my declining years my hands are just not steady enough to manual focus and get good results.

I have thought about a KatzEye or similar to see if that helps, but I think that the reality is that I need auto focus.

I have narrowed down my choice to 3 lens.

A Pentax * Series 300 f/1:4 ish
Sigma 100-300 f/1:4
Sigma 150-500

The first two get very high ratings in the various forums I've checked. The Sigma 150-500 rates a little lower but has the extra reach.

I'd appreciate any feedback from Pentax users who have any of the above.

Cheers

Kevin

[JM Tran]

no such thing as a 300mm f1.4 or 100-300 f1.4, imagine the front element would be probably 1 meter wide

I would go the Sigma 100-300 F4, which is the one u are talking about, it has excellent reputation for birding or aircrafts or sports and very affordable. The constant F4 aperture is better for lighting and focusing than the 150-500, and the zoom lens will be more flexible than the Pentax prime, and good luck on finding a * model as they are very rare, or you have to order one in at a high premium cost.

[Cage]

no such thing as a 300mm f1.4 or 100-300 f1.4, imagine the front element would be probably 1 meter wide

I would go the Sigma 100-300 F4, which is the one u are talking about, it has excellent reputation for birding or aircrafts or sports and very affordable. The constant F4 aperture is better for lighting and focusing than the 150-500, and the zoom lens will be more flexible than the Pentax prime, and good luck on finding a * model as they are very rare, or you have to order one in at a high premium cost.

If you read my post again it says "f/1:4 and not f/1.4, but thanks for the input.

Kevin

[Kym]

I use the 50-500 and it works a treat. The only down side is the weight, but any decent wildlife lens has that issue.

For birding, you need at least 400mm - at least that's what the experts say.

There are a few using the Sigma 150-500 on canon bodies - it just came out on Pentax.

The new version Sigma 50-500 is OS - which is a good thing at 500mm.

Google for reviews.

[JM Tran]

If you read my post again it says "f/1:4 and not f/1.4, but thanks for the input.

Kevin

I hope you know the difference between those 2 Kevin. FYI in the future you should write f4 instead of f1:4 as the latter denotes a maximum magnification at close range. For example, I wouldnt call a Sigma 17-70 1:2.3, or a Tamron 90mm f1:1 - but it should be Sigma 17-70 f2.8-4.5 or Tamron 90mm f2.8. Sorry if I seem pedantic, there are many new members on here and it could mislead them.

[Cage]

I hope you know the difference between those 2 Kevin. FYI in the future you should write f4 instead of f1:4 as the latter denotes a maximum magnification at close range. For example, I wouldnt call a Sigma 17-70 1:2.3, or a Tamron 90mm f1:1 - but it should be Sigma 17-70 f2.8-4.5 or Tamron 90mm f2.8. Sorry if I seem pedantic, there are many new members on here and it could mislead them.

Apologies, I stand corrected, I'll edit my original post to avoid confusion.

Thanks

Kevin

[Cage]

Hi fellow Pentaxians

I've decided to bite the bullet and look for an auto focus lens for birding
.
In my declining years my hands are just not steady enough to manual focus and get good results.

I have thought about a KatzEye or similar to see if that helps, but I think that the reality is that I need auto focus.

I have narrowed down my choice to 3 lens.

Pentax * Series 300 f4 ish (As opposed to the out of my reach f2.8)
Sigma 100-300 f4
Sigma 150-500

The first two get very high ratings in the various forums I've checked. The Sigma 150-500 rates a little lower but has the extra reach.

I'd appreciate any feedback from Pentax users who have any of the above.

Cheers

Kevin

Unfortunately I couldn't edit the original post, so I've edited it here. Hope I haven't caused any confusion.

Cheers

Kevin

[Cage]

Thanks for the reply Kim.

I did look at the Sigma 50-500 but it generally rated a bit lower than the 150-500, but those reviews were probably for the non OS model.

When using this lens on your K20D, do you, or can you, turn off the OS. I always shoot with a tripod or monopod and I'm assuming that the OS is like the built in Shake Reduction where you don't use it unless shooting hand held. I forgot to turn it off once when using my monopod and the results were ghastly.

Cheers

Kevin

[Wizofoz]

Hi Kev,

I have the Bigma 150 -500. I use it to shoot my son playing football. (Aussie Rules) It works a treat. I imagine it would be terrific for birding too.

I shoot hand held on the K-7 and turn off the in body stabilisation, figuring that Sigma know how to make in lens stabilisation for their own lenses.

Here is a link to some of the shots. http://www.flickr.com/photos/owizofo...7624243905151/

Cheers

Wayne

[tim71]

G'day Kev,

there a couple of threads you might find useful

http://www.ausphotography.net.au/for...ht=sigma+bigma

also if you search camera/lenses/gear talk forum using sigma bigma you will find some more fairly redcent threads

I agree with Kym that you want a bit more reach than 300mm. Will be good when Pentax bring out a 400mm lens again.

cheers,

Tim

[tim71]

G'day Kev,

sorry here is the second thread

http://www.ausphotography.net.au/for...ht=sigma+bigma

I also think the Sigma 150-500 is now OS HSM in the Pentax mount.

cheers,
Tim

[arthurking83]

Actually!

the 1:4 aperture denomination is an acceptable way to express it, but the only thing you've got wrong TBB, is that you dont' express it as f/1:4. It's expressed as:

focal length(in mm or cm, as you please) and then simply 1:4 which denotes a focal length to aperture ration of one over four.
it's an old way in which to express it and no longer usd by the mainstream manufacturers. i think a few oddball manufacturers still do it.. (maybe Voightlander, or CZ, or Leica or whoever.. and I have seen it on a modern lens somewhere??)

So, if you had a 50mm f/1.2 lens, and alternative method of expressing that lens and it's max aperture value, is 50mm 1:1.2. .... but not 50mm f/1:1.2

Other acceptable ways to express that same lens type is as...

1:1.2 f=50mm, or 1:1.2 f=5cm ... etc

sorry to be pedantic, but I knew what you were referring too!

[Cage]

Thanks Tim & Arthur

I knew what I meant (I think) although as I'm in my declining years, sometimes I'm not too sure.

Tomorrow, I'm going to instigate the formation of the Australian Procrastination Society, if I remember.

Anyway, I seem to have a penchant for birding, so I'd like something in the 300mm + field, auto focus, to satisfy my LBA. I have a 'K' series 300mm f4 (hope I did that right Arthur), the Pentax 'F' 70-210 and
'M' 80-200 and the almost legendary Tamron SP 70-210 f3.5, all very capable lens, but by the time I settle my shaky left hand (40 years of tennis) and focus, the bird has migrated.

Other than the Pentax 300* series, one other lens seems to keep popping up in the forums as a really sharp performer, and that's the Sigma 100-300 f4. Now I know that 300mm is not really long enough for birding, but I was wondering if a quality 300mm, with a quality 1.4 or 1.7 TC, would be the equal of the 150-500 or the 50-500 siggy.

I've always been a Canon man, but jeez, I really think I can 'get it right' with Pentax. Hope so anyway.

Cheers

Kevin

[arthurking83]

I think it's all pretty much the same at these levels of optics.

I'd say go with the Siggy 100-300/4 and a 1.4x TC. I think Andrew(I@M) has this combo and is happy with it.

This way you get a relatively fast 300mm for when you want that, and then a standard-ish 420mm f/5.6 when you need reach.
I think that either way you'll be shooting in the f/6.1-f/10 range with some birds anyhow, simply for the DOF and contrast(sharpness).

The benefit of having the Sigma 150-500 is the OS to make it easier to handhold for when the tripod/monopod becomes an annoyance.

Unless you really want the extra width of the 50-500 over something like a 150-500, I'd stick to lower zoom ratio lenses

[Cage]

I think it's all pretty much the same at these levels of optics.

I'd say go with the Siggy 100-300/4 and a 1.4x TC. I think Andrew(I@M) has this combo and is happy with it.

This way you get a relatively fast 300mm for when you want that, and then a standard-ish 420mm f/5.6 when you need reach.
I think that either way you'll be shooting in the f/6.1-f/10 range with some birds anyhow, simply for the DOF and contrast(sharpness).

The benefit of having the Sigma 150-500 is the OS to make it easier to handhold for when the tripod/monopod becomes an annoyance.

Unless you really want the extra width of the 50-500 over something like a 150-500, I'd stick to lower zoom ratio lenses

Thanks Arthur.

I agree with you on the lower ratio lens as I'm really looking for the long end.

With the OS on the 150-500 I was wondering how that would go on a tripod or monopod.

I took some shots with my camera anti-shake turned on when using a monopod and the results were unbelievably blurry. My personal anti-shake mechanism is shot, so I'm wondering how good the OS is.

I guess the best way to find out is to try it at a camera store.

Cheers

Kevin

[arthurking83]

Doh!

I forgot you got a Pentax.. with stabilisation on board!

no brainer then.. Sigma 100-300/4 and a 1.4x TC then

in noticed you said Canon at one point somewhere and it seemed to get stuck in my head.

When on tripod, any stabilisation is best turned off. From both what I've seen with my two VR lenses and from what the general consensus is.
It may or may not make a difference in some images(also something I've noted with the 18-105VR lens) but you're best off being safe than sorry.. unless you're doing tests(or like me, forget that your 18-105VR even has VR )

[Kym]

Sigma are making OS lenses for Pentax - which allows you to get the benefit of stabilisation in the viewfinder, albeit at the cost of more power use (less battery life).
They have released both the 150-500 and 50-500 in an OS version.

[doombaj01]

I have both the Sigma 100-300 f4 and the DA*300 f4 and have used both for birds. I use both with Kenko 1.5x TCs. My experience is that I really don't use 100-299mm for birds - very useful for aircraft and sport, but not so valuable for birds. Hence, I have found that the fixed focal length of the DA*300 f4 is not a limitation for birds and it is a fair bit lighter and smaller so easier to hump around. With the TC, and on my K5 or K20D, the DA*300 still tends to hunt in autofocus a bit except in really strong light, but turning off the focus motor and using 'catch in focus' achieves really good results even in low light. They are both really sharp and useful lenses.