[therion]

I´m very interested in this lens. I have Sigma 10-20/4-5.6 EX and I would like to change it because it has only 6 aperture blades. I also don´t like Pentax 12-24 because of 8 aperture blades. New Sigma has 7 - so sun, when photographed at f16 should have nice 14 strokes.

Please, do anybody have this lens? Could do for me some sunshot with f16 or f22?

thanx

[brecklundin]

nobody has it (the F3.5 version) yet...it's not due until October. Many have the 4-5.6 version is it's fine. There is more to the difference than the speed. The F3.5 version uses, as I recall, an 82mm filter which means about US$140 minmum for a decent CPL. I seriously do not think the number of blades is going to matter for much of what ya use this sort of lens for...not much bokeh with them as a rule.

I had my 10-20 in a Canon mount. You would not hate it...there are threads here with lots of details, comments & observations comparing the Sigma and the Pentax. I would choose the 10-20 f4-5.6 again as I was happy with my previous copy. I never would have needed an f/3.5 version which is only slightly faster than the typical 10-12mm I used it set to inside. And remember the current version is about US$430 vs. around US$600 for with the f3.5 of Pentax versions...

In this class I don't think there is a wrong lens option...all of them are excellent.

[therion]

I have Sigma 10-20/4-5.6 and I´m mostly using 82 filters because my Pentax 67 lens 45/4 has 82mm thread and also my Takumar 300/4 has. So I must use 77mm-82mm adapter to use my filters on sigma.

7 aperture blades makes sense for me, greater than You would think!
6 and 8 aperture blades makes poor 6 or 8 strokes on sun. 7 blades
makes nice 14 strokes!


I think new sigma for Pentax is already available at adorama:

202109 Sigma 10mm - 20mm f/3.5 EX DC HSM Autofocus Zoom Lens for Pentax Digital SLR Cameras

[tcom]

How does the IQ of the new 10-20/3.5 compare to the older 10-20/4-5.6.

I do have the 10-20/4-5.6 and I am wondering if the 10-20/3.5 would perform better IQ wise.

[therion]

With K7 I have tried to take movies. Sigma 10-20 has very nice possibilities. Under not very good light conditions there is very big
difference between f4 on 10mm and f5.6 on 20mm. f5.6 is too dark, movie gets more noise. F3.5 constant would be great improvement for me.

[kenyee]

I think new sigma for Pentax is already available at adorama:
202109 Sigma 10mm - 20mm f/3.5 EX DC HSM Autofocus Zoom Lens for Pentax Digital SLR Cameras

Buy it...it's a great lens. Post pictures when you get it

AFAIK, it's not out yet. The samples I've seen from Canon/Nikon users don't lead me to believe it's much better than the current version for landscape use where you usually run at f/11-13...

[brecklundin]

I have Sigma 10-20/4-5.6 and I´m mostly using 82 filters because my Pentax 67 lens 45/4 has 82mm thread and also my Takumar 300/4 has. So I must use 77mm-82mm adapter to use my filters on sigma.

7 aperture blades makes sense for me, greater than You would think!
6 and 8 aperture blades makes poor 6 or 8 strokes on sun. 7 blades
makes nice 14 strokes!


I think new sigma for Pentax is already available at adorama:

202109 Sigma 10mm - 20mm f/3.5 EX DC HSM Autofocus Zoom Lens for Pentax Digital SLR Cameras

Interesting...I would contact Adorama because nobody else has the Pentax mount and nobody was expecting any of them until Oct. I see that Amazon shows none of the mounts in stock but B&H has, as I recall, the Nikon mount.

I love dealing with Adorama but they can occasionally have error's in their online catalog.

Given your location, I would want to know more about a new lens before dropping US$600-US$700 on a lens. Of course I am sure that is WHY ya asked in the first place...geeze, some days I scare myself!! Then again, I don't often listen to that little voice in my head telling me to go slow...hehehehe....I jumped feet first into Pentax dumping Canon, not a mistake but for all I knew then, it could have easily been one.

I can say I never used my 10-20 under F7 in a year of using it. But if you are thinking indoor or even lower light video then I would think you know what the choices are already. Maybe I just do not embrace video on a DSLR is all I suppose. While I can see it for brief occasions, I do not see myself ever using it...They make high quality HD video cams as small as a the K7 already, I would think that would be a much better option. Not knowing a lot, OK, nuttin' , about video cams, are the options in the HD range just a lot more expensive than the lens? I mean you are giving up a lot of control using a K7 for video (or any of the DSLR's with the trendy video feature). I am more of a one device for a particular job...still on vacation or as a contextual back-up info sort of thing I am really intrigued by video, so really do not thing I am an old curmudgeon-like sorta guy...I really just do not 'get-it' yet...once I get my K7 I have a sense I might kinda like it!!

I would say I have actually held off on the 10-20 because of the f/3.5 version pending. I miss the 10-20 too because I used it a fair amount. More than I thought after looking at my old shots. But indoors I never used it w/o flash so never even came close to needing a faster lens.

If they do actually have them in stock, I cannot wait to see sample shots!! And even some video too..

BTW, if they are in stock, in any mount, it has to be very recent as I did not find shots anywhere...then again, some days my attention wanders...hehehe...

[Class A]

The F3.5 version uses, as I recall, an 82mm filter which means about US$140 minmum for a decent CPL.

However, you don't typically use a CPL on such a wide angle lens because of the unavoidable uneven polarising effect.

[brecklundin]

However, you don't typically use a CPL on such a wide angle lens because of the unavoidable uneven polarising effect.

Can you explain that for me? I used this CPL (B+W 77mm Kaesemann MRC SLIM Circular Polarizer Filter | MaxSaver.Net (hvStar)?) all the time on mine. So something new for me to learn...

[Zav]

Can you explain that for me? I used this CPL (B+W 77mm Kaesemann MRC SLIM Circular Polarizer Filter | MaxSaver.Net (hvStar)?) all the time on mine. So something new for me to learn...

Find more here: Polarizers
@OP: why are 14 strokes so important to you? No offense, I'm just curious.

[brecklundin]

Find more here: Polarizers
@OP: why are 14 strokes so important to you? No offense, I'm just curious.

Thanks Zav...interestingly enough that is the page that helped me decide on the B+W CPL for my 10-20mm last year. I admit that I didn't really pay attention to the explainations at the time. To me the author's comment of saying "nonsense" to those who point to the issue of the fact due to the sun constantly moving the sky can look uneven....key word there would seem to be 'can'. And like the author if you get the shot you want using a CPL on a UWA lens, then that is what matters most.

Still it is nice to be more aware of the effect. Still if is a must have tool to carry around in your kit no matter the lens it's for...thanks for the link...love the LL site a lot.

[therion]

Zav: I´m often photographing sun and six and eight strokes seem´s very poor. I´m little bit disapointed with eight blades of Pentax 67 45/4.
Six blades of Sigma 10-20/4-5.6 is even worse.

[therion]

Look here:

https://www.pentaxforums.com/forums/pentax-slr-lens-discussion/60355-new-da-1...ed-11-img.html

Pentax 15/4 Limited has beautiful 14 strokes because of 7 blades!
I expect sigma 10-20/3.5 will have similar. I believe 10-20/3.5 will be very good against the sun, as my 10-20/4-5.6 is.

[Zav]

Ok, so it's just a matter of taste. I thought it may be something "deeper".

[therion]

When You look at 60x80cm print, it is very very deep!