[bossa]

The thread linked here would probably have been a better target for my upload:
https://www.pentaxforums.com/forums/general-technical-troubleshooting/191214-...us-rant-9.html

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Last edited by bossa; 08-21-2012 at 06:46 AM.

[aleonx3]

Here are several examples of the 'crappy' AF of the Pentax K-5. Each shot was separately focused in quick succession using S mode. I only took 4 shots before the bird flew away. Damn shame the focus is such crap.

Pentax K-5 & FA*300 F4.5

As I learned over the years, if you are not in a position (or angle) to get a good shot at it, it is not worth sweating over it. Instead, I rather wait for another opportunities. Does not matter if you have the best tool or not.

[westmill]

The K5s focus system is simply garbage. Knowing about the huge focus sensors helps a lot. As does turning off the SR. Its certainly not good for fast lenses shooting wide open. It would help an awful lot if Pentax were to simply explain such things. Most people that own a K5 have no Idea of these two major facts. For any one that does not know.... the center focus point for example extends out to the very edges of the spot meter markings ( ). If you use those for your focusing instead of seeing the focus square, the keeper rate will rise considerably. The SR can take a second to settle and does not like taking pics in quick succession. I had all the same problems thoughts and feelings over the K5. Now I can make it work. When I use the D300 I focus on an eye. With the k5, it will focus almost as fast... but.... I focus on the face... not the eye. The focus points are big enough to miss altogether and focus on the background if it sees more contrast etc. If you need pin sharp focus with shallow DOF then go manual ! It works well within its limitations.

[bossa]

The K5s focus system is simply garbage. Knowing about the huge focus sensors helps a lot. As does turning off the SR. Its certainly not good for fast lenses shooting wide open. It would help an awful lot if Pentax were to simply explain such things. Most people that own a K5 have no Idea of these two major facts. For any one that does not know.... the center focus point for example extends out to the very edges of the spot meter markings ( ). If you use those for your focusing instead of seeing the focus square, the keeper rate will rise considerably. The SR can take a second to settle and does not like taking pics in quick succession. I had all the same problems thoughts and feelings over the K5. Now I can make it work. When I use the D300 I focus on an eye. With the k5, it will focus almost as fast... but.... I focus on the face... not the eye. The focus points are big enough to miss altogether and focus on the background if it sees more contrast etc. If you need pin sharp focus with shallow DOF then go manual ! It works well within its limitations.

I have a D800E and I find that even with that you still need to be aware of how it is operating to decide what you want to be in focus - you still have to override the AF to get fine control.This is, as you say, especially true when fast glass is being used. But a major advantage of FF is the larger, and brighter, VF which does actually allow you to 'see' what is IN and what is OUT of focus.

[westmill]

I have a D800E and I find that even with that you still need to be aware of how it is operating to decide what you want to be in focus - you still have to override the AF to get fine control.This is, as you say, especially true when fast glass is being used. But a major advantage of FF is the larger, and brighter, VF which does actually allow you to 'see' what is IN and what is OUT of focus.

True indeed ! Another common problem is popular lenses that suffer from excessive field curvature. This has nothing to do with the camera but can make it really difficult to focus. The tamron 17-50 is a great example. Its a top class super sharp lens. BUT... it does suffer from severe field curvature at the 17mm only setting. Knowing your equipment is half of the battle.

[StephenHampshire]

True indeed ! Another common problem is popular lenses that suffer from excessive field curvature. This has nothing to do with the camera but can make it really difficult to focus. The tamron 17-50 is a great example. Its a top class super sharp lens. BUT... it does suffer from severe field curvature at the 17mm only setting. Knowing your equipment is half of the battle.

My Sigma 30mm F1.4 is a pain to focus on the K5! This lens is renowned for high field curvature, although it has some very good points too. I do however find the SR mechanism on the K5 less prone to "wobbly focus" than the K20. With the later, I would often get one shot in the middle of a series of 5 or 6 shots suddenly OOF!
The K5 also seems to struggle in low, mixed light, i.e tungsten, low daylight etc. Seems better indoors in just tungsten/flourescent

[westmill]

My Sigma 30mm F1.4 is a pain to focus on the K5! This lens is renowned for high field curvature, although it has some very good points too. I do however find the SR mechanism on the K5 less prone to "wobbly focus" than the K20. With the later, I would often get one shot in the middle of a series of 5 or 6 shots suddenly OOF!
The K5 also seems to struggle in low, mixed light, i.e tungsten, low daylight etc. Seems better indoors in just tungsten/flourescent

To be honest Stephen, there is no way would I ever buy a lens faster than F2.8 for the k5. The SR i simply now never use at all. I had loads of oomph pics and could not understand why. Most made no sense. One was when i took two shots of a woman on the beach. One vertical and one horizontal pic. The first was fine, the second was totally unusable. The exact same lighting same distance same focus area. Turned the SR off... all is now fine. I now use the K5 in the studio, where its superb. I use 185watt daylight balanced bulbs which allows it to focus ok and I use large powerful studio flash with a wireless trigger for the actual picture taking process. I also use it for landscape work when Im not shooting glamour. I have shot a few weddings with it too and have mixed feelings on its performance here, but that is another story lol

[jani80]

One year ago I still used my Canon 1d mark3 and 5d mark2 cameras. All lenses that I had where good (except one). 16-35 2.8 II, 24-70 2.8, 70-200 2.8 is usm II, 50 1.4, 100 2.0, 15 fish eye 2.8, sigma 120-300 2.8. With the 1d mark 3 I always struggled with images out of focus. It was fast but just produced shitty images. The 5 d mark 2 was very slow again. If I used it for sports the amount of unfocused was huge but really good for stills. The Sigma lens was just shit so I am not going to talk about it. Think how much I payed for that stuff and still had alot of issues. Expensive equipment is not automatically giving you better results.

Now I have my Pentax K-5 and can't complain too much. It is a bit slow for sports but I still get what I want. For stills just no problem at all. So you really should get your body checked. And I absolutely love the Pentax interface and size. Borrowed my friends 5 d mark 2 with the 70-200 last week and I just wanted to throw it away.

All brands have some good and band points. Learn to use it and you get good images. I am really keen to hear what will be announced at Photokina. My 645d is SLOW but I still love it and get really sharp images because I have a different style using it.

[Crosshair]

officially done. I made the switch to the D7k.

after having some time for using and getting used to the camera I will post here my comparison, which I think will be a contribution to all k5 vs d7000 comparisons out there.

thank you everyone, for your input up till now.

[Frogfish]

To be honest Stephen, there is no way would I ever buy a lens faster than F2.8 for the k5.

My favourite lenses on the K5 are ALL faster than 2.8

Zeiss 85/1.4, Sigma 30/1.4, 77 Ltd, 43 Ltd, Cosina 55/1.2 (and I sold the K50/1.2).

[westmill]

My favourite lenses on the K5 are ALL faster than 2.8

Zeiss 85/1.4, Sigma 30/1.4, 77 Ltd, 43 Ltd, Cosina 55/1.2 (and I sold the K50/1.2).

Sorry I never said you cant, just that I would not Lots of people love fast glass on there K5s. My guess is they are shooting mostly in manual focus if they are shooting wider than F2.8 though.

[bossa]

My Sigma 30mm F1.4 is a pain to focus on the K5! This lens is renowned for high field curvature, although it has some very good points too. I do however find the SR mechanism on the K5 less prone to "wobbly focus" than the K20. With the later, I would often get one shot in the middle of a series of 5 or 6 shots suddenly OOF!
The K5 also seems to struggle in low, mixed light, i.e tungsten, low daylight etc. Seems better indoors in just tungsten/flourescent

The Sigma 30 is very sharp in the center but really soft along the edges. I'm not sure how large the sweet spot is but it seems to me that trying to focus any lens with the outer AF points where that lens is soft will hardly work anyway. Nikon people are saying that they are having issues with the outer AF points on the D800 with wide angle lenses (24mm), although I am at a loss to explain why a WA would work differently than a 'standard' or tele lens in this regard. The possibility of the lens being softer out toward the edges (thus confusing the AF system) seems a real consideration to me.

Faster lenses are going to work better in low light for AF and MF too. If the image going to the sensors is brighter due to the faster lenses it seems probable that AF will work better in low light with a faster lens attached doesn't it? Obviously an F/1.4 lens in low light is going to have a brighter image to work with than an F/4 lens (or even F/2.8) so before blaming the camera it might be an idea to think about which lenses are doing this the most.

I have never had any dramas with my K-5 in low light and it doesn't seem to be any worse than my D800E in that regard.

PS: The K-5 AF system is not meant to be used with lenses slower than F4 when a Teleconverter is a attached so it's easy to imagine a F4 zoom not really working well in dim light by itself.

[Michaelina2]

officially done. I made the switch to the D7k.

after having some time for using and getting used to the camera I will post here my comparison, which I think will be a contribution to all k5 vs d7000 comparisons out there.

thank you everyone, for your input up till now.

You've wasted enough of your time around here, don't you think? Are you NOT aware that the K-5 and D7k are obsolete? They are old news. What makes you feel your commentary will NOT be like (say) a comparison of a K110D to a D90? Trust me... No one cares...

Like most around here, I've already moved on...

Why not just spend your time learning how to use your (new to you, but) old toy, instead.

And enjoy...

[Andi Lo]

You've wasted enough of your time around here, don't you think? Are you NOT aware that the K-5 and D7k are obsolete? They are old news. What makes you feel your commentary will NOT be like (say) a comparison of a K110D to a D90? Trust me... No one cares...

Like most around here, I've already moved on...

Why not just spend your time learning how to use your (new to you, but) old toy, instead.

And enjoy...

Not true. I've been contemplating this change myself due to AF, with the same initial issue that the OP posted. (plus sync speed issue for me). I have K20, K-x, and K10 and they all exhibit this same issue. My goal is to get a D700 but I wonder if I should make a baby step to D7k first to accumulate lenses before jumping to FF.

I'll be looking forward to the OP's impressions as I'm in a similar boat.

And who cares if the toy is old, as long as the client is happy The camera is just a tool. Heck my favourite camera is still the K100d

[bossa]

I've got a D800E (and a few nice lenses for my Nikon) and there's no way I'd sell off my Pentax K-5 to replace it with a D7000. Another D800 maybe but definitely not a D7000. People dumping full Pentax systems so close to Photokina are just crazy.