K-50 auto focus, question please?


Gedski

Link Posted 20/05/2014 - 19:22
It is some little time since last I visited. The reason being that I have had, in the ensuing time a Canon 650D.

Now I have been given the chance to change /upgrade my camera, I have the auto focus problem back. I have mentioned here previously that I have always had an affection for Pentax cameras. When I last got the chance to go for a DSLR, I was torn between the Pentax and the Canon.

Despite much searching and asking of questions I could not get a definitive answer to this one question. How much slower is the auto focus on, now, a K-50 and a Canon 70D?

My current research reveals that at least one review of the K-50 says that it's auto focus is very fast and on a par with the equivalent 'Canikon' cameras. While most say that it still lags behind.

I enjoy doing birds in flight shots, however, I am by no means what you would call a photographer but I manage to get some decent shots. Would I notice the difference in the two cameras auto focus or would only a professional photographer notice?

This will be my final camera change so I would like to get some accurate and definitive responses, please.

Gravelrash

Link Posted 20/05/2014 - 20:11
You may find answers a little thin on the ground. I could be very wrong but I don't seem to notice many forumites using the K-50!

I shall be interested in seeing how many responses you get
Steve

Sometimes I'm serious and sometimes not, but I consider sarcasm an artform. Which is it today?

SteveEveritt

Link Posted 20/05/2014 - 20:13
You shouldn't have any issues, unless the bird is flying straight at you at 90mph. But even a Canon would struggle with that!
My Flickr link

"Life is what happens to you while you're busy making other plans" (John Lennon)

sbrads

Link Posted 21/05/2014 - 18:43
AF speed is very lens dependent on both cameras. Canon has more choice in fast AF long lenses, but that doesn't mean you can't do as well with the K-50 but you'll have to do your lens research before buying.

walt

Link Posted 21/05/2014 - 19:32
I can't help you with the exact models you state, but I do have the K30 and an old canon 30D plus I do a lot of BIF's. I use an internal focus lens on the K30, a pentax FA*300 F4.5 and a HSM lens on the 30D, a sigma 100-300 F4.
Judging focus speed I'd say no difference that I can notice. However BIF's are not just about that, it's about the camera picking the right way to focus for a start, the Canon is better at that. It's about predictive af, the Canon is better at that. And it's about not loosing af when locked on. Perhaps a draw on that, perhaps Canon is better if you move away from just using center af point. I don't know if this helps....?
Walt
My newer photos google photos
My older Flickr photos Flickr
Even older ones Picasa

SteveLedger

Link Posted 21/05/2014 - 20:40
I recently bought a K-50
AF is very fast with my two main lenses, a Sigma 30mm f1.4 and the Tamron 17-50mm f2.8
It's also very quick in low light.
I have never come across anyone with a 7D so I can't comment on a comparison, but one thing I have noticed is that manual focus seems to be the same speed with all DSLRs!

Smeggypants

Link Posted 21/05/2014 - 21:05
sbrads wrote:
AF speed is very lens dependent on both cameras. Canon has more choice in fast AF long lenses, but that doesn't mean you can't do as well with the K-50 but you'll have to do your lens research before buying.

Indeed. AF is glacial on my DA* 50-135, yet I've got an old Vivitar 19-35 Zoom and the AF is brutally fast and clunks on it's target within a split second
[i]Bodies: 1x K-5IIs, 2x K-5, Sony TX-5, Nokia 808
Lenses: Pentax DA 10-17mm ED(IF) Fish Eye, Pentax DA 14mm f/2.8, Sigma 17-70mm f/2.8, Pentax-A 28mm f/2.8, Sigma 30mm F1.4 EX DC, Pentax-A 50mm f/1.2, Pentax-A 50mm f/1.4, Pentax-FA 50mm f/1.4, Pentax-A 50mm f/1.7, Pentax DA* 50-135mm f/2.8, Sigma 135-400mm APO DG, and more ..
Flash: AF-540FGZ, Vivitar 283

richandfleur

Link Posted 21/05/2014 - 21:49
There is an AF-C continuous auto focus mode also, which works quite well in some situations, but you'd have to ask a serious bird photographer how they achieve their in flight shots with Pentax equipment.

AF-C is often quoted around the time a Pentax locks up though, but there may be nothing in that...

Gedski

Link Posted 24/05/2014 - 10:21
Thanks for all your assistance gentlemen, especially to Walt. I have had a look at your shots on flickr. I'm impressed. I now need to decide which way I am going to jump.

Gravelrash

Link Posted 24/05/2014 - 14:02
Gedski wrote:
Thanks for all your assistance gentlemen, especially to Walt. I have had a look at your shots on flickr. I'm impressed. I now need to decide which way I am going to jump.

Due to your compliment of Walt's images I looked through his linked images. The clear answer is it doesn't matter which system you go for. His cameras are all over the place but he gets awesome images from all of them.

I hate talented people
Steve

Sometimes I'm serious and sometimes not, but I consider sarcasm an artform. Which is it today?

Gedski

Link Posted 27/05/2014 - 19:26
After much deliberation I have reduced my new camera choices down to just two. They are, the Canon 700D and the Pentax K5 II, not the 's' model.

I know what I shall get with the Canon 700D, so it will need no further discussion. I am unsure what the K5 II will give me. I do not have any concerns about all types of 'still' shots. My concerns are only about my birds in flight shots. I do all mine handheld only [ the camera, that is , not the birds].

I have sought out the K5-II because of the SAFOX focusing system thinking that this will enable me to do decent birds in flight shots. I would like to hear from any of you who have the K5-II and 'do' birds in flight shots. I should also add that I need to make my final choice by this Friday.

My lenses are to be one of the proprietary 70-300mm and either a Pentax 18-50mm or 50mm f1.8 lens. Please can you help me in my dilemma?

johnriley

Link Posted 27/05/2014 - 19:32
Ideally you would visit a dealer and try the cameras you are interested in, to see which ones handle best in your hands. The larger Jessops should make this possible, certainly you'd be OK at the Manchester store.
Best regards, John

Mike-P

Link Posted 27/05/2014 - 20:03
I have the K-5II and a 7D ... the af on the 700D is not quite on a par with the 7D but it is still pretty good. I have to say I love my Pentax gear and will pick it up 99/100 times over the Canon but when it comes to birds in flight (and therefore camera tracking ability) the Canon is certainly better. Also Canon lenses are mostly built for fast autofocus whereas Pentax still need to catch up in this area.

As much as it pains me to say, if it's fast af with decent tracking ability you are set on then go with Canon (although I would look hard at the 70D over the 700) but if it's excellent image quality with decent ergonomics, weather sealing and that warm fuzzy feeling every time you look at your photos then go with Pentax.
. My Flickr

walt

Link Posted 27/05/2014 - 22:15
Gedski and Steve (Gravelrash) thanks very much for those comments on my flickr stuff, much appreciated.
About the Canon 700D and the K5II have you seen the fnac.com report on the af of these? If not have a look at their pdf here link unfortunately it is in french but google translate does a reasonable job if you don't read french. Also the figures are reasonably self explanatory.
It's very difficult to say how this will translate into real life af with birds in flight and more consumer oriented lenses. I know my Pentax 55-300 is considerably slower to af than my canon 55-250 IS and that has an impact on tracking. Also I borrowed a friends canon 70-300 IS and that is also faster to af than my pentax 55-300. Any chance you could borrow or rent the kit to try out first? I tried to evaluate the af of the K5 and DA300 in a shop and high street and I just couldn't draw a conclusion on how it would perform for birds in flight.
Walt
My newer photos google photos
My older Flickr photos Flickr
Even older ones Picasa

richandfleur

Link Posted 27/05/2014 - 23:25
walt wrote:
I know my Pentax 55-300 is considerably slower to af than my canon 55-250 IS and that has an impact on tracking. Also I borrowed a friends canon 70-300 IS and that is also faster to af than my pentax 55-300.

It's been raised before but there are pros and cons to any automatic system. The general thoughts on this are along the lines of:

(From an industrial control point of view) Canon reaches the setpoint faster, but can have overshoot. So can be quick but not necessarily accurate. (eg Blue Line below)

Pentax doesn't overshoot but takes longer to get to the focus point. Prioritises accuracy over speed. (eg Red Line below)




Your aperture value probably comes into play here also, as to how wide your in focus depth of field is, and therefore how precise the focus point actually needs to be.

That's fine from an initial locking on point of view, but Pentax has never be particularly well known for then being able to predict and move with the focus object. There is an AF-C mode, but how fast this works and how applicable it is to your requirements I can't say.
Last Edited by richandfleur on 27/05/2014 - 23:27
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