All Forum Comments
Comment by jeallen01 posted on Sigma 120-400 apo dg hsm os at 06/04/2022 - 17:55
[quote:3496ace15f="jeallen01"]
Actually, having bought and then sold (it's now in Russia!) a 150-500 DG OS HSM because of the relatively slow AF compared with the 100-300 F4 (mainly because of the former's much longer focus travel), my biggest concern is the AF speed.
NB: that was/would be when using it with a K-3/K-3 II which have much stronger focus motors than the earlier Pentax DSLRs. [quote]
... Bump to ask if anyone can comment on the length of the focus travel (i.e. how far do you or the motor have to turn the focusing mechanishm in the barrel to focus the lens from/to closest focus to/from infinity) ?
Actually, having bought and then sold (it's now in Russia!) a 150-500 DG OS HSM because of the relatively slow AF compared with the 100-300 F4 (mainly because of the former's much longer focus travel), my biggest concern is the AF speed.
NB: that was/would be when using it with a K-3/K-3 II which have much stronger focus motors than the earlier Pentax DSLRs. [quote]
... Bump to ask if anyone can comment on the length of the focus travel (i.e. how far do you or the motor have to turn the focusing mechanishm in the barrel to focus the lens from/to closest focus to/from infinity) ?
Comment by jeallen01 posted on Sigma 120-400 apo dg hsm os at 06/04/2022 - 16:19
Pwynnej wrote:
Depending on which camera model you have getting reliable AF at f8 would be a huge ask... even with f8-compatible Nikons (D500, D850, D5/6) AF performance is limited at f8, possible at f11 but only just.
Actually, having bought and then sold (it's now in Russia!) a 150-500 DG OS HSM because of the relatively slow AF compared with the 100-300 F4 (mainly because of the former's much longer focus travel), my biggest concern is the AF speed. Depending on which camera model you have getting reliable AF at f8 would be a huge ask... even with f8-compatible Nikons (D500, D850, D5/6) AF performance is limited at f8, possible at f11 but only just.
NB: that was/would be when using it with a K-3/K-3 II which have much stronger focus motors than the earlier Pentax DSLRs.
By comparison, using any TC with with the 120-400 is a much lesser one!
PS: As well as the slow focusing, that 150-500 didn't seem very sharp or contrasty, even when it had achieved good focus lock, and so that was the other reason I sold it.
Comment by jeallen01 posted on Sigma 120-400 apo dg hsm os at 05/04/2022 - 09:45
reso wrote:
Home on Friday if you can wait it'll post photos with the 1.5 for you to look at
No problem!Home on Friday if you can wait it'll post photos with the 1.5 for you to look at
Comment by jeallen01 posted on Sigma 120-400 apo dg hsm os at 04/04/2022 - 22:46
reso wrote:
Will post photos later this week as I am away from home and yes used it with a 1.5 pz and result were OK used it with a 2.o and would not lock on kept hunting
Hope that helps
Thanks and my experience with the Sigma 100-300 F4 and Sigma 2.0 TC was similar at times.Will post photos later this week as I am away from home and yes used it with a 1.5 pz and result were OK used it with a 2.o and would not lock on kept hunting
Hope that helps
Will be interested to see some shots!
Comment by jeallen01 posted on Sigma 120-400 apo dg hsm os at 04/04/2022 - 22:37
Photos please
PS: have you used it with the Kenko PZ T/C?
PS: have you used it with the Kenko PZ T/C?
Comment by jeallen01 posted on Sigma 120-400 apo dg hsm os at 04/04/2022 - 22:17
I only hope that the buyer realised that if it should break, then there aren't any spares still available from Sigma!
Comment by jeallen01 posted on Sigma 100-300mm F4 Apo EX DG £179.00 at 04/04/2022 - 19:43
Mike-P wrote:
Probably fell off and got lost - that's what they (including the one on my earlier version of the lens) generally doJonathan-Mac wrote:
stub wrote:
Good. Sigma 17-70mm on the Wex used site at present. I dont know how much they bring. But to me this seems very good value at £151..!
https://www.wexphotovideo.com/sigma-17-70mm-f2-8-4-dc-macro-hsm-lens-pentax-fit-...
That's a good deal. It's the newest version too.Good. Sigma 17-70mm on the Wex used site at present. I dont know how much they bring. But to me this seems very good value at £151..!
https://www.wexphotovideo.com/sigma-17-70mm-f2-8-4-dc-macro-hsm-lens-pentax-fit-...
Quote:
Supplied with: Original box, front cap, rear cap and manual.
No mention of the hood.Supplied with: Original box, front cap, rear cap and manual.
OTOH, I don't think I'd swop my lens for anything else South of £200 because I really like it
Comment by jeallen01 posted on APS-C standard zoom lenses at 01/04/2022 - 13:27
Ref the locking pin, if only one could cut the same sort of thread as found in most older shutter release buttons then an old-style locking release cable could be fitted to make timed long exposures easier - alternatively, remove the actual button and superglue it to the shutter panel and screw the cable release directly into that????
Comment by jeallen01 posted on A macro lens that is not a macro lens - Radionar 50mm at 10/12/2021 - 13:13
Afternoon.
I've just had to do a complete reinstall of Firefox and then re-establish my logins to many sites, including this one - and I had a problem in actually even finding this one!
I'm using the Duckduckgo search engine and, whereas it found others like the US forum and even several probably dead pentax-centric forums, it totally refused to find this site at all in multiple searches!
I then had to resort to using a link in an old email from Rick H to lead me back to the site!
Something for the guys looking after the site (maybe Rick?) to look into as it seems like this site is not on the radar of at least one of the major search engines.
I've just had to do a complete reinstall of Firefox and then re-establish my logins to many sites, including this one - and I had a problem in actually even finding this one!
I'm using the Duckduckgo search engine and, whereas it found others like the US forum and even several probably dead pentax-centric forums, it totally refused to find this site at all in multiple searches!
I then had to resort to using a link in an old email from Rick H to lead me back to the site!
Something for the guys looking after the site (maybe Rick?) to look into as it seems like this site is not on the radar of at least one of the major search engines.
Comment by jeallen01 posted on A problem for new people looking for this site at 29/11/2021 - 18:32
I am pretty sure that from the K-3 (or maybe it was the K-3II) Pentax bodies stopped working with Sigma HSM lenses correctly when using a teleconverter with SDM contacts. From what I remember it was when Ricoh bought out the Pentax 1.4x, they released a firmware that supposedly fixed an "issue" with SDM but in the process it stopped the Pentax converter working with Sigma HSM lenses. I always thought it was to stop us using the new 1.4x with Sigma HSM and In the process it also stopped the Kenko and Teleplus converters that had the SDM contacts from working with Sigma lenses as well.
Really annoyed me at the time as my Sigma 70-200mm OS HSM started mis focusing straight after the firmware update as did a couple of other HSM lenses I had.
Could have been just my experience though.
My 3 pennath on the above : Before I sold the 150-500 HSM in early 2018, I found I could use my Kenko 1.4x pz tc with that lens on the K-3 II and it would still autofocus but VERY slowly (the lens had been checked out by Sigma Imaging in 2015 because I thought it focused very "slowly" - but apparently that was normal for that lens!:roll.
Therefore, if there was that sort of f/w update then I presume it happened after about mid-2018 as I always updated the camera f/w as soon as possible after it was released.