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Forum: Pentax K-5 & K-5 II
03-03-2016, 02:59 PM
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Just a quick tip for situations where you expose your gear to great temperature differences: Bring sealed plastic bags!
Especially helpful in winter. If you expose your gear to below zero celcius degrees, wrap it in a plastic bag before bringing it back in. Let it warm up in there for a good hour or so, before unpacking it, et voila no condensation whatsoever ;)
(The reason behind this is that actually the different air temperatures are at fault for causing condensation.)
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Forum: Troubleshooting and Beginner Help
04-14-2017, 07:43 AM
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+1 for the 21mm. Focal length-wise its similar to Smartphone cameras, which i think is very suitable for most applications. It is my most used lens. I would recommend getting the green ring-version. its cheaper on ebay (~300 eur) and gives you great looking starbursts
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Forum: Troubleshooting and Beginner Help
07-28-2016, 01:45 AM
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what nobody explained yet, is that the camera in the second two shots overexposed, thus the flare that you see as "blue haze" just set exposure compensation to -0.7 or similar and you will be fine.
about the filters, usually i keep them on to protect the front element, when walking around and/or being on the move to somewhere. however for critical shots i suggest to remove it.
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Forum: Pentax K-1 & K-1 II
04-29-2016, 08:47 AM
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is there a video or something of the sort that shows the focus peaking in action? Would be nice to see how pentax implemented it in their latest model
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Forum: Pentax K-1 & K-1 II
04-22-2016, 11:40 AM
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I'd really like to see that combo, preferably with the batterygrip attached :D
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Forum: Pentax SLR Lens Discussion
04-06-2016, 04:15 PM
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same with my copy, thanks for posting, i was wondering whether i was alone in this ^^
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Forum: Pentax SLR Lens Discussion
04-03-2016, 03:46 PM
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I have found the 21/3.2 ltd (smc) to be the perfect lens for traveling, it does everything! full body/ half body portraits, landscapes, cityscapes etc. I have it with me when ever i want to go light and unobtrusive.
you may want to consider the equivalent 31/1.8 ltd on the K-1 ;)
or else you could look at the 20-40/2.8-4 ltd. nice range, light, small, weather sealed, but no star bursts :S
your choice :)
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Forum: Troubleshooting and Beginner Help
01-03-2016, 03:58 PM
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If i may propose a different idea,
while the sigma 18-35/1.8 is a stellar lens, there seems to be a high degree of sample variation with focus-errors (thus you may have to also rely on MF there), also its quite an expensive option.
in your position, i would consider a fast 50mm like the FA/1.4 (it gets you the option to stand back a little) alongside the tamron 17-50/2.8. you can find those two used for much less than the sigma and it gives you more flexibility.
(in case you wish to go wider, i can recommend the pentax da 14/2.8, it has soso critics, but i find it especially fun for people photography in narrow spaces)
hope that helps ;)
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Forum: Pentax SLR Lens Discussion
11-27-2015, 03:40 PM
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thank you guys very much for your posts. it gave me some good ideas what to pay attention to when testing :)
I will post some pictures over the weekend, when i find time to do proper testing.
thanks again, love this forum :)
cheers,
sebastian
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Forum: Pentax SLR Lens Discussion
12-02-2015, 04:40 AM
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hey pjv,
first of all thank you so much for taking the time to write all these detailed answers. Im sorry for my rant, but I was really angry how something so simple as AF adjustments could get so difficult for no apparent reason.
I understand your DOF calculations and it all makes sense to me now, I havent really thought this through in the beginning, excuse my simpleness!
I will do the 3d testing and also look to work on my technique, i heard snipers always shoot after exhaling because it keeps the hand more steady. Im trying to copy that ^^
just two little questions remain unresolved for me:
the issue of front/back- focus changes with the focal length, is this normal for such a lens?
as i mentioned above, the two AF adjustment options given do not seem to be substitutes to each other i.d., i have to use both to dial in the necessary adjustments, is this normal?
Thanks for your time and helping a fellow out :)
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Forum: Pentax SLR Lens Discussion
11-30-2015, 04:03 PM
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If only it was this easy ;)
no really, Im at a loss. The inconsistency of my auto focus defies any logic _whatsoever_ :hmm::hmm:
I know there is no perfect AF, and at 2.8 autofocus tends to get it wrong on the old K-5, but this is just...
There are two AF dials: "Apply all" and "apply One"
1st problem
Keeping one of these at +/- 0 and dialing in AF adjustments with the other has no significant effect, or is not enough to get within 10% error margin of decent focus.
I thought these two dials were substitutes to each other? so that you cannot achieve like +20 AF adjustments?
"Apply all" for every lens mounted on the camera
"apply One" for each single lens individualy
but from what I experienced they both impact AF performance simultaneously. I always thought AF to be within the range of -10 to +10, not within -20 to +20
2nd Problem
Both AF adjustment options do not impact AF performance in the same way.
a +10 / +2 is not the same as a +2 / +10
is this really how its supposed to be?
3rd Problem
AF adjustment inconsistency.
I had made a test at 16mm and i wrote down the adjustments (+2 / +10) i dialed in. After i tried some other adjustments i wanted to go back to the old setting, and had dialed in (+2 / +10) again and voila: totally different results with severe backfocusing! I mean what is this :mad:
i think i dont need to mention that the results i gathered from my earlier adjustments from 2 days ago produced different results this time
please, im really looking for ideas how to deal with such things.
The lens is not bad, if it achieves focus it is actually pretty darn sharp, even at 2.8 and 16mm the center sharpness is good! But i feel like its my camera that poses all these problems.
The test i made was very similar to the one before, 45° ruler with steady camera etc etc.. only that i had to rebuild the testing scene.
I will mount my other lenses and see how they will perform. I really hope there is a solution to this problem.
Best Regards,
Sebastian
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Forum: Pentax SLR Lens Discussion
11-28-2015, 08:17 AM
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hey pjv,I have followed your advise and set up my ruler likewise.
Unfortunately i dont have upload space anymore on PF here, so the 50mm is missing. but it is as before just a hair below the 70mm mark at about 69 mm
Focal distance was about 55cm
here the 100% crops:
36mm 2.8 +10
28mm 2.8 +10
20mm 2.8 +10
16mm 2.8 +10
the results are reproducable, the 35 and 28mm tend to be above the 70mm mark, while all other FLs remain below 70mm.
So i cannot make any AF adjustments without sacrificing sharpness for other FLs.
A dreadful situation :S
@ rondec thanks for the tip! I will look into this tonight, the ruler was just a lot quicker to setup ;D
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Forum: Pentax SLR Lens Discussion
11-28-2015, 05:36 AM
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UPDATE:
so i spent some time making the AF adjustments according to the tutorial on the mainpage:
"The adjustment process is quite simple:
Choose a clear subject that has something in front of and behind it (lens alignment tools work best)
Take a photo with autofocus enabled
Check if focus is accurate on your computer monitor at 100% magnification
If things in front of your subject are sharper than the subject itself, apply a -1 focus correction and start over from step #2
If things behind your subject are sharper than the subject itself, apply a +1 focus correction and start over from step #2
If your subject is perfectly in focus, you are done!
Read more at: https://www.pentaxforums.com/reviews/lens-align-front-back-focus/the-remedy.html#ixzz3smunlkYL"
and i had to apply a full +10 to get it to an okay level:
now the extreme FLs 16mm and 50mm are a tad (maybe -1) too front focusing, while the medium range (20,28,35mm) are still back focusing by about +2. However i cant test this as I am at the maximum with +10.
That seems a little odd maybe. however i used a common ruler. The focus distance was about 0.6 meters or just a hair below 2 feet, according to the scale on the lens. I havent done any infinity testing yet.
See for yourself below (Focus Point is between the 70mm and 71mm mark):
50mm f2.8 AF +10
28mm f2.8 AF +10
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Forum: Pentax SLR Lens Discussion
11-27-2015, 06:53 AM
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thanks for the quick replies guys :)
so Im shooting with my old trusty K-5. However this body does have some focus-errors! Even on my manual lenses (50/1.7; 85/1.8) it shows wrong focus confirmation.
So I am aware of these issues.
The problem with a zoom of course is that you can only dial in the fine adjustments that applies to all focal lengths(FL).
I have a tripod, a flash, not a cable release but Im trusting in the 2 second delay-option :)
Possible explanations for my mixed results may be:
not adequate holding of the lens
too slow shutter speeds
In body stabilization going rampant
wrong AF fine adjustments
So I am aware of these things, the solution to get reproducable results is of course using a tripod. the questions im having are:
What are the FL that i should test (16,28,35,50) ?
what subjects should i use to test for sharpness ?
how do i go about the whole testing procedure ?
and lastly, did anyone find (if there is any) a sweetspot for the lens, where it is sharpest?
cheers,
Sebastian
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Forum: Pentax SLR Lens Discussion
11-27-2015, 03:49 AM
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Hey folks,
no test pictures at this time, sorry!
I am just asking for the best way to assess sharpness on the pentax 16-50 f/2.8 ? What would you recommend?
I got this lens for a steal basically and on the outside it does not have a scratch, optics seem perfect aswell. Im just pondering whether it has a problem with element-alignment.
The pictures seem uniformly sharp at f8 and above (even f/18 seems to be very alright at the pixel level, diffraction might not be a big issue here) but below f/4.5 Im not so sure anymore. Sometimes the pictures turn out quite good, and sometimes not so much. However all pictures are okay with 50% crop, if i zoom in further, details degrade heavily, so is this lens supposed to be sharp at f/2.8 ?
At which focal length does the lens naturally perform best?
The autofocus does give a very ever so slightly squeaking sound. is this normal? (it might be that the lens hasnt been used in years, does it get better with time?)
thanks for your time :)
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Forum: Mini-Challenges, Games, and Photo Stories
03-20-2015, 06:00 PM
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wow what a file, is this the camera or the lens? i mean wow! i never could pull such detail from my k-5
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Forum: Pentax Price Watch
10-25-2014, 08:37 AM
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Hey guys,
just found this on another website and thought i'd share it with you
DxO & Digital Photographer | www.dxo.com
you simply have to enter your email and the captcha. the key and download link is then sent to you via email.
However, i havent tried it yet so dont get mad in case of problems :)
cheers,
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Forum: Photo Critique
02-01-2014, 04:25 AM
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