[MarK-1]

Hello,

I'm new here, and this is my first post. I really like this forum.

I've just started using a K-1 with a DA* 300mm F4. I've set the in-camera lens AF Fine Adjustment (Wrench Menu item 25) and further AFC/spot but I find myself using the manual focus more than the autofocus, especially on moving subjects.

Reasons:
- I find the autofocus is very good on static subjects, but is searching a lot when subjects are moving.
- I sometimes find the level of accuracy of the autofocus not accurate enough, in relation to the level of detail that can be achieved with this camera. In spot mode, I sometimes think the spot is too big(?).....

I've included two samples of a hand held manual shots.

For K-1 / DA300mm users: What is your experience with this combo? Did you manage to find a setting that improves the autofocus, both in accuracy and (tracking) speed?

Thanks!

Attached Images

View Picture EXIF

File Date

 

View Picture EXIF

File Date

 

[cali92rs]

I do not like AF accuracy, especially tracking with the DA300mm + K-1. I am not sure what it is, but that lens seems to be better behaved with the K-3II (at least that is my experience).
As a contrast, I just acquired a DFA 150-450mm, and holy cow it is like night and day. The DFA was much better regarding AF. It must have to do with the old SDM.

[Tas]

For K-1 / DA300mm users: What is your experience with this combo? Did you manage to find a setting that improves the autofocus, both in accuracy and (tracking) speed?

Hi MarK-1, welcome to the forums.

The K-1/DA*300 is a very good combo actually.

Having said this it's been a while since I've had mine on the K-1, but on that occasion it was my first opportunity to do some action shots with the combo. And whilst I do have to acknowledge it is slower than the D-FA* 70-200 and D-FA 150-450, the images from the DA*300 are worth the effort.





I have several images using the K-1/DA*300 combo on my Flickr stream that show the combo can AF and capture nicely detailed images. The DA*300 is streets ahead of the 150-450 if you need to shoot wide open. I've never had an issue shooting the DA*300 at it's widest aperture so if you need to be longer than 200 and the light is not good the DA*300 is likely to be more flexible due to it's performance at F4. The newer D-FA is nice and sharp too, but I've taken to stopping down to f7.1-f8 to avoid the softness wide open. As mentioned already, it's probably the SDM that is slowing the DA*300 during AF but you have the ability to manually focus whilst in AF to assist if it's starts racking back and forth or is slow catching up to your subject.

To aid the AF I recommend you set up the camera to use back button focus. This is quicker to focus with and allows you to concentrate on tracking without having to balance the shutter half press as the K-1 has a very light shutter. Try both shutter release options. With AF-S it might be best to set it to focus priority. With AF-C I use back button focus and release priority. I will get some extra images that are out of focus but more chance of getting images in focus.

For action I'm obviously using AF-C and have primarily been using centre weighted metering and zone select (9 AF points). I usually leave it on zone select when I go back to AF-S as well. I've not yet tried all the focus setting options, but have found with moving subjects that the central spot is harder to track with, which maybe just me but I've had a better keeper rate using the zone select option. Other's should be along to provide feedback on their expereince too I hope.

The next point to consider is whether you intend to shoot in RAW and gain access to the full resolution of the camera or use the crop mode or jpegs to gain access to faster camera function and better buffer response. One of the problems with the K-1 for action photography is the large files writing to the card. As I'm using full resolution and RAW I'm accepting a compromise that the camera will be slower but those images I do get will be larger. This can be a real pain but that has meant I changed the way I capture action shots. I've tried using continuous medium and low, but motorcycle racing is too fast for this approach so I tend to leave it on continuous high and accept that I need to pause regularly for the camera to write to the card. You have three options for continuous shooting so try them and see if they suit your work.

I now need to admit my bias for this lens. I've always liked the DA*300 and consider it one of the best Pentax lenses available. Yes SDM can be a pain and it would be nice to see an updated DC version, but it's a great lens now IMHO.There might be better lenses suiting your needs, but I'd suggest that you give this lens a go with different technique before looking at something else.

Anyhoo, hopefully the above will assist.

Tas

[AussieTrev]

I think the combo works well.

https://www.pentaxforums.com/forums/12-post-your-photos/323352-nature-who-sai...hard-shot.html

An example that I shot.

[Sigmund]

What's your ratio of hits to misses Aussietrev?

[Grognard]

Having only tens of days of experience with this wonderful lens, but I'd like to share the following:
PDAF: Quick and steady in bright outdoors environment, sluggish in low light
CDAF: Sluggish in general, inclined to hunt without human intervention (which means it very much needs your manual aiding). I personally don't ever think of using CDAF in action shooting with any lens featuring an original Pentax SDM
MF: Feels almost like a manual focus lens
Sharpness: Once you are shooting steadily this lens is surprisingly pleasing. The combination with K-1, which features a 5-axis shake reduction, enables you to shoot by hand as slow as 1/30.
Bokeh: Fantastic. The objectives are popping out of the screen.

As a verdict, this is a wonderful combination. And why I'm saying that is because of K-1's improved AF and 5-axis SR, and because of DA* 300's modest weight and amazing IQ. These two Pentax creatures, when mounted together, pushes you go out into the wild life.

[ChatMechant]

I haven't been able to do a full workout with this combo yet wrt AF tracking but in other ways it performs very well and is sharp as ever.
here's a full shot and a (snip tool) 1:1 crop straight outta lightroom, no sharpening, etc.

---

Last edited by ChatMechant; 06-28-2017 at 12:58 PM.

[MarK-1]

All: thank you for you comment and great pictures.
@Grognard, I agree that the possibility of this combo is a challenge that I'm willing to pick up very much.
@Tas, on my next trip I will take up the tip of using the back button focus, together with the 9 zone AF and AFC. Shooting jpeg's or raw's is indeed depending on the situation. I agree that this is a great lens. I uploaded the file assuming you could zoom all the way in, but as that's not possible, I've included the 1:1 crop of the dragonfly. You can see it actually forgot to shave that morning!

[MarK-1]

I agree there is a difference in AF performance between the dedicated new DFA lenses and the other/pre K-1 era lenses.
I just bought the 28-105, which is a brilliant lens for it's price and AF is so much better, even in focussing on object that have hardly any contrast.

[AussieTrev]

What's your ratio of hits to misses Aussietrev?

Sorry about the late reply, missed your post. I don't do a lot of bird shooting, this was a lucky day, sun right, bird right, me right. This day was not a couple shots for success.