[slow2focus]

Yes, the green button is used for stop-down metering for the Pentax M lenses while your mode dial is set for M for manual mode.

For M42 lenses, you can either use the M mode or switch to Av mode without the the need of green button. For M42 lens, I usually use the Av mode and skip the stop down metering with green button.

You have to use the customize setting to allow aperture to be set on aperture ring.

Thanks,
Hin

My experience with M42 lenses are different than everyone I read here. With everything properly set up, in Av mode, the meter will consistently change and the F number will display ---. I get wild exposures (I can't compensate for) from shot to shot. They are always underexposed but not by the same amount meaning, same subject/framing I get say -2 stops. Same light different subject or framing, I get say -1 stop or -1.5 stops. I can not just do a general comp for the lens currently on. So, I can't shoot Av mode at all with M42 on my k-x. I end up shooting M with either comp button or green button (they do the same thing) to set exposure. The buttons will get me in the ball park still almost always under exposed, but, much closer according to histogram.

I only M lens I have has a small fungus so I am afraid to attach to the k-x for fear of spreading. I don't have experience with M lenses.


thanks

Just on my second day with my K-X, can't wait to get out and about, but one from my desk, just a low light desk lamp -DA40 f4.5 1/15 iso12800 no PP, just resized

[hinman]

My experience with M42 lenses are different than everyone I read here. With everything properly set up, in Av mode, the meter will consistently change and the F number will display ---. I get wild exposures (I can't compensate for) from shot to shot. They are always underexposed but not by the same amount meaning, same subject/framing I get say -2 stops. Same light different subject or framing, I get say -1 stop or -1.5 stops. I can not just do a general comp for the lens currently on. So, I can't shoot Av mode at all with M42 on my k-x. I end up shooting M with either comp button or green button (they do the same thing) to set exposure. The buttons will get me in the ball park still almost always under exposed, but, much closer according to histogram.

I only M lens I have has a small fungus so I am afraid to attach to the k-x for fear of spreading. I don't have experience with M lenses.

thanks

Perhaps, you should have a separate thread on Lens forum to diagnose your problem. Make sure of the obvious such as

• The customized setting in menu where you allow aperture to be changed on aperture ring. You need to change from the default "prohibited" to "allow" setting. I am sure you've done that
  
• It is normal to get F-- in exif for aperture in both M lenses and that of M42 lenses. This is one of the known drawbacks to m42 lenses besides flash support.
  
• Check if your m42 lens has A/M for auto or manual diaphragm setting. Make sure it is on the M setting as Auto diaphragm will require a body support to depress the M42 pin to do the stop-down metering in closing down the iris opening of the lens. Our digital bodies can only support M setting of manual diaphragm as it does not have the means to depress the diaphragm pin on the back. You can reference an article blog post on M42 adapter with inner ring for auto-only m42 lenses for reference.
  
• Related to above, check to ensure if your M42 is auto-diaphragm lens and without the A/M switch on lens barrel. And those lens has a spring loaded pin that only stop down if the pin is depressed; otherwise, the lens iris is fully wide open whatever aperture you turn. You can check on holding the lens only and change aperture and observe the iris. If you have either M setting or you depress the pin on back, you will see iris opening changes with the aperture setting

The metering on M42 lens is not consistent for different bodies. I have not used any M42 lens on my K-x but I will guess it is similar to K20D. If it is anywhere close to K-7, that will be the best as few others have mentioned more accurate metering on K-7. On K100D or K10D, there are non-linear variations of Ev compensation, only some cool souls in Pentaxian community could document. In K20D, I found reasonable consistent metering for most cases in Av mode. For some M42 lens in my possessions, there is always light falling off towards wide open aperture and I usually dial in +0.3 to +0.7 for Ev compensation to the light fall out. With better M42 lens, the light fall off is not as severe and hence less tweaking. All in all, I found M42 lens to be quite consistent in K20D. I can't say the same for K-x as I have not used K-x exclusively on M42 lenses.

Your mileage may vary and I highly encourage you to open a thread on M42 metering with the exact make and model with the lens, best with lens' product picture on rear and test picture with rough exif if you remember them. It is also important to find out if your lens has A/M switch or if it is auto-only M42 lens.

Hin

[hinman]

Just on my second day with my K-X, can't wait to get out and about, but one from my desk, just a low light desk lamp -DA40 f4.5 1/15 iso12800 no PP, just resized

Nice showing of the highest iso picture for K-x. It is a rewarding experience with K-x. I have mentioned a couple of times that the DA 40mm limited is probably the best combo with the K-x due to form factor, small size and big on IQ combination with K-x high iso performance. The f/2.8 in the DA 40mm shines with K-x in iso 3200 with pretty clean shot, easy to work on with iso 6400 and somewhat usable image on 12800 if you don't pixel peep for perfection. It is unfortunate that DA 40mm limited is priced higher than it used to. I bought my copy used for $249 in BHphoto in the used department.

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Last edited by hinman; 01-22-2010 at 12:08 PM.

[hinman]

Shot with Pentax K-x white and Tamron 70-300mm f/4.0-5.6. The purple fringe is most apparent in #2 and it is unfortunate from the Tamron zoom which performs quite well otherwise.

shot through a windows and hence the blur compared to previous two
With a tap on the cheek, the white beluga whale comes up to kiss the close encounter program with participants



shot with Sigma 17-70mm f/2.8-4.5 in dark aquarium on basement floor looking into the beluga whale.

[yt]http://www.youtube.com/watch?v=Hn2LnV2ubzs[/yt]

Pentax K-x White in Seaworld Part 1

[hinman]

In a dinner with low light, I changed from auto-WB to the preset tungsten WB and I can see more from the pictures. I did some NR in iPhoto for shots over at 6400 and above.

auto WB
1/25 sec, f/3.5, 23mm, iso 12800, 0 Ev
way warmer than the actual scene and hence
I switched to preset tungsten WB after the 1st shot




preset tungsten wb
1/100 sec, f/4.5, 70mm, iso 12800, -0.3 Ev




preset tungsten wb
1/50 sec, f/3.5, 34mm, iso 12800, -0.3 Ev




auto wb
default NR, no pp
1/60 sec, 26mm, f/4.0, iso 5000, 0 Ev




preset tungsten wb
default NR, no pp
1/40 sec, f/2.8, 17mm, iso 5000, -0.7 Ev



High ISO habit with Pentax K-x

The K-x changes how I shoot in low light. I usually don't shoot anything above iso 1600 with my K20D. I rarely found the need as well as courage for iso 3200+ as I mostly rely on fast primes with Cosina 55mm f/1.2 or my FA 50mm f/1.4 and try to avoid the grain and noise in high iso pictures.

With the K-x, it is a great combo with regular zoom and fast (but not necessary the fastest) primes in f/2.8 and the iso 3200 give me a pretty clean image with my Sigma 17-70mm f/2.8-4.5 traveling zoom. The K-x definitely changes how I shoot indoor. By no means, the pictures are great samples as you can see the grain and noise and some loss of detail. The preset tungsten balance works better for me in the dinner shooting, color are very close to what I saw in the dinner dim light setting.

Hin

[rparmar]

Just on my second day with my K-X, can't wait to get out and about, but one from my desk, just a low light desk lamp -DA40 f4.5 1/15 iso12800 no PP, just resized

Nice headphones. I have the AKG K271 which I believe are the best value in their price range.

[hinman]

I just downloaded the 1.01 firmware. I want to follow up with more user report on my K-x white.

I can't find any mirror slap-up issues with consistent soft images out of my copy of K-x.

Summary of my settings:

• everything default in JPG
• use extended iso range from 100 to 12800, adjust iso range subject to scene
• default NR in medium
• bright image mode
• customized Ev to 1/3 instead of 1/2
• customized ISO to go with Ev increments
• center focal point in AF-A
• sharpness adjusted from +1 to +2 and toggle between Fine sharpness and the default, still experimenting

Few observations to share:

• K-x has more tendency in over-exposure than my K20D
• occasional hiccup in locking up once a video clip is displayed. This may have to do with my SD card. When that happens, I need to take out battery in order to turn off the camera
• unreliable AWB in indoor tungsten and fluorescent lighting, preset tungsten WB helps a bit but AWB seems way warmer than the actual scene
• I can't see the Viewfinder clearly in cloudy outdoor and dark indoor scenes. This may be due to my use of bi-focal glass
• image a bit soft in default setting, hence I turn up the default +1 sharpness to +2 sharpness and I am trying between Fine Sharpness vs the default sharpness
• Love the DA 40mm on my K-x, AF is fast and responsive even in dim lighting
• In general, I prefer my K20D body over K-x when I am shooting manual focus lenses
• The LCD resolution can't tell a blur picture from a sharp picture.

1/125 sec, f/3.2, 40mm, iso 100, 0 Ev

Hin's User Settings with K-x

Thanks,
Hin

[einstrigger]

More of a cosmetic question than performance one, but how's the white body holding up? I initially purchased the K-X white bodied version, but exchanged it for a black version in fear of having dirt and smudging collect on the nice "white" exterior. Have you had to clean it often?

[efg]

Thanks for posting your experiences and the examples. It's very helpful to a new user like me.

[hinman]

More of a cosmetic question than performance one, but how's the white body holding up? I initially purchased the K-X white bodied version, but exchanged it for a black version in fear of having dirt and smudging collect on the nice "white" exterior. Have you had to clean it often?

I have used my white K-x for over 2 months now, smudge was my initial concern but it is an non-issue for me with real usage. I find the body material in white k-x is quite tolerant to smudges. I have a cleaning practice not proven yet to be safe, I did use baby cleaning wipes in a traveling trip to clean my camera after a day of use. Other than the trip, I don't find the need to clean my white k-x. It is as good as new.

The white body, though beautiful in my opinion, does have the impression of cheaper plastic when compared to the black body.

Thanks for posting your experiences and the examples. It's very helpful to a new user like me.

Thank you.

[orlovszki]

Hy Hin
After reading your review, I have sold my old K-m and got yesterday a white K-x.
The bodies are, indeed, the same, except the meaning of some keys and two holes for speaker and mic.phone. Although I was afraid of the white color, it looks great. Anyway, my wife will happily use it after K-8 will be mine.
The difference between K-m and K-x is inside, and is really big. I must say that I had to read again the booklet to discover those lots of extra gadgets.
In a couple of days I can share my experiences of K-x, compared with K-m (after 6000 pics made with it).

[orlovszki]

By the way. Since my first camera was a Russian Vilia - from 1980, I had to learn how to set and compose each shot. I must say that ten years ago i could put 37 photos out of a film of 36 because I had to think twice before pushing the button.
Nowadays i shot hundreds of pics in one afternoon and can easily delete the main part of my shots. Do you remember the feeling of making pics with old film cameras, and waiting to fill up a roll, take it to the shop and waiting for it again to be processed. Perhaps after long weeks you have realized if the moment was captures well or not.
Nowadays we have HiTech gadgets and we complain about features that 5 years ago were unknown. My first camera has manually operated, we had to step the distance between us and the subject, we had to watch inside the film box to get the right speed / aperture ratio. Therefore a good picture had a real value at that time.
Before saying I am oldfashioned I also appreciate all the functions that came with K-x even if I will never use most of them in my entire life (just like the mobile phones which came with lots of senseless applications.
So, I believe the red dot is helpful but not necessary.

[hinman]

<skip>
So, I believe the red dot is helpful but not necessary.

I am glad that you don't have an issue with the red dot. Though it is not necessary, I still miss it and I will prefer to have it than not having it especially in dim lighting. I wear bi-focal glass, I find red in center much more easy to see than the green on bottom for referencing in focus as a focusing aid. Again, this is subjective.

In general, I prefer to use my K-x with AF lens and my MF lens with 'A' setting. The best to use with K-x are the DA limited and DA lens series with quick shift focus feature. And I found the green button behavior a bit odd in using with manual type of lens. With a M lens, the stop-down metering goes with extra mirror flipping and I can't find the reason why the mirror has to flip in metering for M lens.

Thanks,
Hin

[Canada_Rockies]

I am glad that you don't have an issue with the red dot. Though it is not necessary, I still miss it and I will prefer to have it than not having it especially in dim lighting. I wear bi-focal glass, I find red in center much more easy to see than the green on bottom for referencing in focus as a focusing aid. Again, this is subjective.

In general, I prefer to use my K-x with AF lens and my MF lens with 'A' setting. The best to use with K-x are the DA limited and DA lens series with quick shift focus feature. And I found the green button behavior a bit odd in using with manual type of lens. With a M lens, the stop-down metering goes with extra mirror flipping and I can't find the reason why the mirror has to flip in metering for M lens.

Thanks,
Hin

The sound you hear is not the mirror flipping but rather the aperture stopping down. It gets dark in the viewfinder while stopped down, and makes noise. Using the green button you get a quick stop down, darkening the viewfinder, followed by an immediate opening of the aperture. If you watch carefully you will see that the subject is always visible. Try it at f/5.6 and you will see that it just darkens briefly.