[mhertel]

I am looking for an AF lens thats at least 400mm long. I recently acquired a Sigma APO 400mm, but it's a manual lens and it just takes me too long to get everything right.. (I'll probably be selling that here again in the not too distrant future) I guess not having perfect vision any more doesn't help either
I want to spend around the $1000 mark for a decent long range zoom lens. So far I have the Sigma "Bigma" 50-500mm in mind, but I wonder if there is anything else out there that would be worthwhile looking at.
Main uses would be for wildlife and astro photography.

Again, it has to be AF, no manual focus lenses

EDIT: For Astro pics, I mean like pictures of the moon etc, not heavy duty astro stuff

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Last edited by mhertel; 09-22-2008 at 09:59 PM.

[David07]

Here are some other options:

- Sigma 100-300mm f/4 + Teleconverter 1.4X

- Tamron adaptall 300mm f/2.8 LD IF 60B + Pentax AF TC 1.7X (the lens itself is manual focus but has automatic aperture with adaptall to PKA adapter, but becomes AF (AF only in the central point of the picture) if used with the Pentax TC 1.7X).

- Sigma 400mm f/5.6 APO Tele Macro: this one is AF

Not available yet in Pentax mount:

Sigma 150-500mm f/5.6-6.3 and Sigma 120-400mm f/4.5-5.6
These two lenses will have HSM


When the announced Pentax TC 1.4X SDM will be availabe, it can be used with the Pentax DA* 300mm f/4.

These are the options I have in mind.

[palmor]

In addition to Dave's list, the Tokina AT-X 400 f/5.6 SD and Sigma 70-200EX with 2xTC




John

[sveinmb]

You do say you're looking for a zoom, but I think you really should consider a prime if you're looking for something beyond 300mm. There are very few zoomlenses in that range that don't have some sort of compromise on either sharpness or loss of light. The Bigma does have f6.3 in the tele end and that might not be too easy to autofocus unless it's bright daylight. Perhaps some owners of that particular lens can enlighten us on just that, but from my experience, even f5.6 can be a bit slow when autofocusing birds/wildlife.

I have the Tokina AT-X 400/5.6 that palmor mentioned, and I think it's a very good performer and quite cheap as second hand buy. A lot cheaper than your 1000 dollar budget. The build quality is excellent (all metal) and very compact for a 400mm. On the downside however a bit noisy when focusing and has a rather loud metallic noise when the focus ring bangs onto either end of its range.

You can see a sample from my AT-X in my flickr photostream: Eurasian Oystercatcher on Flickr - Photo Sharing! I do have more images, but they haven't yet found their way to flickr.

The Sigma EX 70-210 is also a great performer, but I'm not too sure if you'll be happy with the results using a 2x teleconverter. The lens is a tiny bit softer at the long end, and this will be more pronounced using a 2x converter. Using the 1.4x it's quite good, I think there is at least one sample of that in my photostream as well, but 300mm range is not what you were asking for

If you can manage a 300/2.8 prime like the Tamron SP with the 1,7x af adapter within you budget that might be one hell of a combination. Both should be able to give you excellent results and the 300 itself can be used in situations where another tele would just give up because of low light.

If you still want a (new) zoom, the Sigma 100-300/4 has a great reputation, and with the EX 1,4x converter it will probably still be a great performer. Sigma also has newer lenses on its way with sdm/hsm, but who knows how long it will be until we see them. There was also a Tokina AT-X 80-400mm zoom. I don't know much about it other than it's every compact and known to be quite sharp. It's not the easiest one to get hold of.

You can even start saving for a Pentax FA* 250-600/5.6


As a sidenote. I don't know much about astrophotography, but the best shot of the moon I've made this far comes from a very cheap Sigma 600mm/f8 mirror..

[mhertel]

Choices, choices

Yes, I'm not too fond of using anything with a 2x TC.. I'm not even looking at anything that smaller than 300mm for that reason alone. I do have the Tamron 1.4 TC, but you need great glass to start with.
If the DA* 300mm where just a bit faster..
Zoom is not a requirement, but could be handy. The FL of the Bigma is very appealing

[Lowell Goudge]

I have 2 combos which I have posted results previously, but also a comment.

Sigma APO 70-200 F2.8 EX (origonal version) and sigma APO 1.4X and 2X TCs

https://www.pentaxforums.com/forums/187646-post19.html

Pentax SMC 300mm F4 and 1.7x AFTC

https://www.pentaxforums.com/forums/106132-post4.html

For wild life, especially birds, autofocus is not always better. Autofocus cannot see through twigs in front of birds the way humans do. manual focus is sometimes nmuch more precise.

[mhertel]

For wild life, especially birds, autofocus is not always better. Autofocus cannot see through twigs in front of birds the way humans do. manual focus is sometimes nmuch more precise.

True, but I rather AF and then adjust.. If I still had 20/20 vision then MF would not be too much of a problem

[Lowell Goudge]

True, but I rather AF and then adjust.. If I still had 20/20 vision then MF would not be too much of a problem

I have 20/50 vision, and wear corrective lenses when I use the camera, I do this because when my glasses are off, I can't see the things at a distance that I am focusing on.

[mhertel]

I have 20/50 vision, and wear corrective lenses when I use the camera, I do this because when my glasses are off, I can't see the things at a distance that I am focusing on.

I tried using my Camera with glasses on, I can't do it Well, I havent tried too hard

[John Kovarik]

I am myopic also. I can attest to the quality (including IQ) of the Sigma 100-300 EX DG and the Sigma 1.4 DG TC. At the long end it compares favorably with my DA* 300 but allows dor those frequent situations where 300 (or 420) mm is just too long for the right composition.

[Miserere]

I have the AF Sigma 400mm f/5.6 (non-APO) and am surprised at how well it performs. Good wide open, very good one stop down and beyond. The only issue is avoiding purple fringing, although PP can take care of that if it appears. Works well with the Tamy 1.4x TC, retaining both IQ and auto-focus.

But hey, if you've got a budget of $1k, you might as well buy something new.

[Ben_Edict]

I am looking for an AF lens thats at least 400mm long. I recently acquired a Sigma APO 400mm, but it's a manual lens and it just takes me too long to get everything right.. (I'll probably be selling that here again in the not too distrant future) I guess not having perfect vision any more doesn't help either
I want to spend around the $1000 mark for a decent long range zoom lens. So far I have the Sigma "Bigma" 50-500mm in mind, but I wonder if there is anything else out there that would be worthwhile looking at.
Main uses would be for wildlife and astro photography.

Again, it has to be AF, no manual focus lenses

EDIT: For Astro pics, I mean like pictures of the moon etc, not heavy duty astro stuff

O.k. I chime in. Received my Bigma just two days ago, but couldn't test it thouroughly, due to the current Photokina, which I attend from early morning til late... One thing I notices right away: AF is not too fast on my K20. One could also say it is a bit on the slower side and hunts sometimes, iof the target has no strong contrast edges.

I was astonished, after all I read so far, that the lens is by far not as big and heavy as I expected it to be. But I use my Sigma 70-200/2.8 all the time and sometimes even the Tamron 300/2.8 with 1.4x-TC handheld, so I am used to heavy lenses.

IU cannot say anything about image quality yet...

What I can say for sure is, that this would be the last of my lenses I would use for astrophotography! No way. Too slow! And the zoom and focus mechnisma will probably creep and you get unsharp pictures. I have read in another comment (soryy, I really cannot remember whether it was even in this forum), that the "zoom creep" of the Bigma is more of a "zoom bang". Though mine doesn't bang loudly, the lens tube simply slips down immediatly, if you let the camera hang from its strap...

Apart from that, I wouldn't use a zoom lens for astro imaging at all, just too many lenses inside and the mechnicas needs to be more loose, than in a prime lens...

If you want to use your lens really for both purposes, I would surely go for a Pentax DA 300/4 and a 1.4x tc, though which tc to choose is another matter...

Ben

[mhertel]

Thanks for the "review" of the bigma and your impressions.. Really don't like the zoom creep aspect of it.. Oh well, on to search for another lens.. seems the DA*300 doesnt want to go away

[Blue]

Sigma 150-500mm f/5.6-6.3 and Sigma 120-400mm f/4.5-5.6
These two lenses will have HSM

There is also this one: Sigma 135-400mm f4.5-5.6 APO AF

[Snapshot12]

When Sigma 70-200 F2.8 HSM fitted with Sigma 1.4x or 2x Teleconverter on Pentax, due to the contacts on the Tele, the lens loses HSM function,as a result it CAN NOT Auto Focus, Only MF.

Thats why sigma has just released the new teleconverters for SONY mount just to retain the HSM, but no news for PENTAX mounts yet as usual....and dont worry about Canon or Nikon mounts,they have been looked after from the start.

Though I do believe when the newly-announced Pentax Tele is fitted on any sigma HSM lens, it should be working fine. We will wait and see.