[repaap]

I do believe that many will be in to a big surprise. Not just because of that eye AF, but subject tracking in general. And speed. Especially when one is using these new lenses KAF 3&4. I’m waiting quite much too an hoping my economical situation to improve quick(not just because of this camera lol).

---------- Post added 04-08-21 at 22:11 ----------

And on top of that, I do believe that quite many will cough that premium early adopter price up. Literally we have nothing like this before.

[mattt]

I wish Rene Fisher would bring some discussion to this thread. She's been doing bird photography in Canada (Ontario) and I think if there was anyone to speak to the use case I'm interested in it would be her.

[Rondec]

A theoretical topic??

What ever happened to "glass is forever"??

Even I am still using a screw-drive Sigma 10-20mm {because I didn't see any reason to purchase the newer version of a lens I don't use very often}
and a FA 28-105mm {because I needed a standard lens where I could control aperture from the lens as my K-30 started to experience "Dark Image Syndrome"}.

I have stated my desire for Pentax to release a 'consumer level' KAF4 standard lens in case I get a K-90 and it too has solenoid issues,
but I don't really expect them to do so, so I will keep the FA lens even if I do purchase a K-90 and retire the K-30 'for good'
{it no longer is backup for the KP and I no longer expect to ever need it}.

I just the screw driven system has more "slop" in it. If you aren't using AF-C there is a double check that happens that adjusts if the focus isn't perfect with the initial focus attempt, but with AF-C that doesn't happen.

This wouldn't particularly be an issue with wide angle lenses and lenses with smaller apertures because the increased depth of field will cover any little errors. The issue would be mostly with longer lenses with wide apertures.

I guess I would just say that my guess is that if you need to use telephotos with AF-C it might be worth getting a DFA or DA lens with DC or PLM. My guess is SDM probably wouldn't keep up terribly well either.

[One3rdEV]

Rene's sponsored ambassador feedback at Ricoh Imagining's Pentax K-3 Mark III 'Impressions' site is schedule to become available April 16. Based on observation of the trend so far- it is likely that we will not hear or see anything from her anywhere regarding the new product until after that date.

[reh321]

I just the screw driven system has more "slop" in it. If you aren't using AF-C there is a double check that happens that adjusts if the focus isn't perfect with the initial focus attempt, but with AF-C that doesn't happen.

This wouldn't particularly be an issue with wide angle lenses and lenses with smaller apertures because the increased depth of field will cover any little errors. The issue would be mostly with longer lenses with wide apertures.

I guess I would just say that my guess is that if you need to use telephotos with AF-C it might be worth getting a DFA or DA lens with DC or PLM. My guess is SDM probably wouldn't keep up terribly well either.

This does not disagree with my first two sentences.

A theoretical topic??

What ever happened to "glass is forever"??

I may not have to change my plans, but - from comments made here - some members here will have to consider lens usage if they are considering the K-3iii.

[MMVIII]

A theoretical topic??

What ever happened to "glass is forever"??

Even I am still using a screw-drive Sigma 10-20mm {because I didn't see any reason to purchase the newer version of a lens I don't use very often}
and a FA 28-105mm {because I needed a standard lens where I could control aperture from the lens as my K-30 started to experience "Dark Image Syndrome"}.

I have stated my desire for Pentax to release a 'consumer level' KAF4 standard lens in case I get a K-90 and it too has solenoid issues,
but I don't really expect them to do so, so I will keep the FA lens even if I do purchase a K-90 and retire the K-30 'for good'
{it no longer is backup for the KP and I no longer expect to ever need it}.

In how far is a hypothetical new k-90 with a hypothetical aperture system with a hypothetical failure that could be overcome by a hypothetical user -that does not want to let it hypothetically repair or use the existing 16-50 plm - anything more than a theoretical topic? In best case 🤣

[reh321]

In how far is a hypothetical new k-90 with a hypothetical aperture system with a hypothetical failure that could be overcome by a hypothetical user -that does not want to let it hypothetically repair or use the existing 16-50 plm - anything more than a theoretical topic? In best case ��

The current discussion is about the very real K-3iii and members who should consider their use of very real older telephoto lenses before they spend a lot of money - as explained twelve minutes before you responded.
Nothing else is appropriate here.
I will not engage in further discussions about theoretical situations.

---

Last edited by reh321; 04-08-2021 at 01:55 PM.

[Smolk]

My only concern is at the very wide end. I don't have the DA 15mm Ltd and read that its edges are mushy, and I'm not using wide too often to justify the DA* 11-18mm, while the DA 12-24mm is too prone to CA as far as I can see. I may still consider the 15mm, but wish for some improvement.
Well, I'll probably wait for a little while.

[rogerstg]

I do believe that many will be in to a big surprise. Not just because of that eye AF, but subject tracking in general.

I would agree, but I hope they are in for a good and not unpleasant surprise. I hope it plays well with DA* lenses as well as Sigma DC HSM lenses, especially the bigmas. I guess time will tell, so for now I'll have to wait and see.

[repaap]

I would agree, but I hope they are in for a good and not unpleasant surprise. I hope it plays well with DA* lenses as well as Sigma DC HSM lenses, especially the bigmas. I guess time will tell, so for now I'll have to wait and see.

I suppose that you’ll get the best performance with PLM lenses. In terms of AF speed. Less hunting and better performance will be there for other lenses too for sure. I have only one HSM lens and it is 85/1.4 EX. I’m not having high hopes, since it is old already. But I’ll try it for sure, perhaps that new RGBiR sensor will work miracles and with subject tracking it will be good with that lens too.

[tduell]

I have only one HSM lens and it is 85/1.4 EX. I’m not having high hopes, since it is old already. But I’ll try it for sure, perhaps that new RGBiR sensor will work miracles and with subject tracking it will be good with that lens too.

I have three Sigma HSM lenses, one being the 85 f/1.4 EX, all of which I use on the K-1 and K-3 II, and I find the AF to be very fast for all these lenses.

Cheers,
Terry

[repaap]

I have three Sigma HSM lenses, one being the 85 f/1.4 EX, all of which I use on the K-1 and K-3 II, and I find the AF to be very fast for all these lenses.

Cheers,
Terry

Af is fast, but in some circumstances it tend to hunt. It hunts fast thou. It is not just my copy, it is quite known thing. But. With this AF it could be the thing making that (those) lenses more reliable and then also faster. My friend has 150-500 which he don’t use. I might buy it off his hands.

[jpzk]

If KAF2 (for SDM), I don't know because I don't have one. no tested yet. i think it may be good, just not 100% performance of K-3 Mark3.

For me, SDM = DA*300/4 ... I sure hope this will not deter me from getting the K3III.

[Tesla]

For me, SDM = DA*300/4 ... I sure hope this will not deter me from getting the K3III.

I think KAF2 and newer with a in lens motor such as SDM, DC or PLM are all good for AF-C. I'm sure some motor technologies work better than others, but I think they all preform well. I believe the only difference between KAF2 and KAF3 is that KAF3 drops screw drive support.

Here is a good article I found on the K-mount:
The Evolution of the Pentax K-mount - Articles and Tips | PentaxForums.com

[jpzk]

I think KAF2 and newer with a in lens motor such as SDM, DC or PLM are all good for AF-C. I'm sure some motor technologies work better than others, but I think they all preform well. I believe the only difference between KAF2 and KAF3 is that KAF3 drops screw drive support.

Here is a good article I found on the K-mount:
The Evolution of the Pentax K-mount - Articles and Tips | PentaxForums.com

Thanks for the info!