Forgot Password
Pentax Camera Forums Home
 

Showing results 1 to 14 of 14 Search:
Forum: Pentax K-30 & K-50 06-25-2017, 01:32 PM  
K-30/K-50 Aperture Control Problem/Black Photo Repair - How I did it.
Posted By Owltown
Replies: 50
Views: 15,563
Superby detailed instructions, supported by sharp and detailed photos: THANK YOU! Being as my K-30 is also gathering dust thanks to the aperture block failure, I will try this repair myself. With patience and no caffeine (plus that bath towel you recommend) it should go well. BTW there was a plus to the K-30's failure: It justified the purchase of a K-3 ... !

---------- Post added 06-25-2017 at 04:41 PM ----------


I wonder if the design logic parallels that of solenoid valves on natural gas / propane appliances. In case of electrical power failure, these valves are designed to "fail safe", i.e. in a closed position. Electric current holds them open, mechanical spring pressure forces them closed when de-energized.
Forum: Repairs and Warranty Service 05-20-2017, 04:41 PM  
K30 Aperture failure advice
Posted By Owltown
Replies: 12
Views: 1,024
On further careful study, I see that my K30 does have the aperture block failure. Any lens with a fully auto diaphragm (any KA series for example) stops down to its smallest opening regardless of light conditions or camera mode setting. I can see this by looking right into the lens and firing the shutter under different light conditions. The reason I can shoot with my old SMC-M lenses is that the lens mechanically limits stopping down to the opening I manually preset. So now I gotta buy a K3, I guess....
Forum: Repairs and Warranty Service 05-14-2017, 05:14 PM  
K30 Aperture failure advice
Posted By Owltown
Replies: 12
Views: 1,024
Thank you -- I will try that in daylight tomorrow.
Forum: Repairs and Warranty Service 05-14-2017, 04:14 PM  
K30 Aperture failure advice
Posted By Owltown
Replies: 12
Views: 1,024
I wonder if the problem I'm having is related to the aperture block issue. I use a K30 with a K-mount SMC-M 50mm f4 macro lens. I use AV mode in a studio environment, shooting tabletop images with constant lighting. The K30 body was purchased new and now has a shutter count around 20,000. Recently I noted that the shutter speed does not change as the aperture is adjusted. I've looked into the lens when shooting, and the aperture is indeed stopping down correctly throughout the lens's full range. But I cannot get proper exposure other than at a single f-stop setting. Changing ISO has no effect.

Just as a test, I mounted a SMC-DA 18-55mm "kit" lens and shot in AV mode. The problem was unresolved: Correct exposure in AV mode at only one f-stop setting, In P and AutoPict modes, the lens aperture can be seen closing down, but the images are consistently 4 to 5 stops under-exposed.

This is not a show-stopper for the kind of photography I'm doing, but I'm limited to shooting everything at f5.6 to get correct exposure, and using the +/- adjustment simply to correct the equivalent of an f-stop or two, for unusually dark or bright subjects. Any ideas or suggestions? Thanks!
Forum: Pentax K-30 & K-50 07-30-2016, 02:22 PM  
Dark exposure problems on K-30 or K-50? Read me first!
Posted By Owltown
Replies: 56
Views: 11,522
Well, that is worrisome. I have a K-30, about one year old, with 6900 actuations and no problems to date. However, 98% of my exposures are made with legacy glass and the camera in "M" mode. When I read of the aperture block failures, I thought I'd be immune as auto aperture is of no consequence, shooting this way: All that the camera is being asked to do, is meter through a pre-set lens and set the shutter speed correctly. Photolady95's situation suggests that something else, something more than aperture block is failing. Is this thought correct, and if so, have other K-30 users experienced that sort of failure? Thanks!
Forum: Pentax DSLR Discussion 07-30-2016, 01:59 PM  
Aperture Block / Shutter Failure
Posted By Owltown
Replies: 37
Views: 3,244
Based on experience, if you choose to go the M42+adapter route, search for a genuine Asahi Pentax adapter from the 1970s -- when the company first introduced K-mount film cameras. I bought two different adapters from Chinese vendors on that famous auction site; both, once mounted on my DSLR body, were virtually impossible to remove. Other analog shooters have reported the same problem. The genuine adapter works as designed.
Forum: Pentax K-30 & K-50 06-08-2015, 05:26 PM  
Body Construction: K30 vs K50
Posted By Owltown
Replies: 12
Views: 2,316
Hmmm.... A brand new K50 at about the price of a lightly-used K30.... plus the ability to add the extended warranty. That sounds like an even better deal. Edgar_in_Indy: I shoot mostly tabletop, small to midsized products, indoor under lights. Much of our daily work is for eBay sales, the rest for a local manufacturer. 95% of my shots are made with an SMC DA 16-45mm ED AL zoom, bought new about 6 years ago. Occasionally I have to shoot tiny items (<1/2" across), and then I use, believe it or not, a non-AI Nikkor 85 f1.8 on a Panagor zoom macro converter, with a Nikon to PK adapter. This allows fullframe shots with objects as small as about 0.33" across, with surprisingly good sharpness, and plenty of brightness wide open for manual focus.
Forum: Pentax K-30 & K-50 06-07-2015, 05:44 PM  
Body Construction: K30 vs K50
Posted By Owltown
Replies: 12
Views: 2,316
Many thanks to all who replied, especially to Edgar_in_Indy for the two photos. I shoot studio work almost exclusively; I'm using a K20D with over 60K shutter actuations. It's been a workhorse but may be close to shutter failure. A new K3 would be a delight, but it exceeds the budget! Since my cameras are rarely exposed to the outdoors environment, the plastic-over-metal subframe should be 100% adequate. Roberts Photo has dozens of K30s with <1K shutter actuations available at <$300, so that's what I'll get. Thanks again!
Forum: Pentax K-30 & K-50 06-06-2015, 05:18 PM  
Body Construction: K30 vs K50
Posted By Owltown
Replies: 12
Views: 2,316
Hello -- I'm about to purchase either a K30 or a K50 body and am a bit confused as to the body construction of these two models. Reviews here on the Forum state that the K30 has a polycarbonate body, whereas the K50 is said to have a metal body under a plastic cover. Yet both bodies have exactly the same net weight. Can anyone clarify this? Do both the K30 and K50 have metal sub-frames, or are both 100% polycarbonate? Thank you!
Forum: Pentax K-01 03-12-2012, 04:36 PM  
Working with the K-01 in full sunlight
Posted By Owltown
Replies: 50
Views: 4,956
Points well made about the video functions. If they do not add cost or interfere with still operation, plus assist in marketing the camera, they are a good thing. If one doesn't want to use them, nothing is lost. Regarding accurate focusing: My eye has done a fine job focusing on the target part of the subject, manually, with SLR cameras, for decades. Without actually using the K-01, I cannot see any practical gain from an artificial aid like focus peaking -- unless one was working in extremely low-light situations.
Forum: Pentax K-01 03-12-2012, 02:31 PM  
Working with the K-01 in full sunlight
Posted By Owltown
Replies: 50
Views: 4,956
Thanks to Adam's superbly detailed review, I can tell that this is not a camera I'd invest in. Critical focus in all lighting conditions is essential. The lack of a proper viewfinder with full protection from ambient light relegates this camera to the point-and-shoot class IMHO. What benefit do you derive from being able to use all your high-dollar K-mount glass, if you cannot be assured of sharp focus each and every time? I shoot a lot of close-up work, using a K20D in manual focus mode most of the time, and get consistent results no matter where the light source is relative to the back of the camera. I also cannot understand the obsession manufacturers have with including video capability in still cameras. If I want to shoot video, I'll use a dedicated video camera. Don't make me pay for spurious video technology in my still camera -- give me a hooded electronic viewfinder instead!
Forum: Pentax K-01 03-12-2012, 01:44 PM  
Sticky: Pentax K-01 Review Posted
Posted By Owltown
Replies: 88
Views: 50,638
The shutter is open for viewing, then closes and reopens for the exposure and the live image.... Sounds like a Contaflex....!
Forum: Pentax K-01 03-12-2012, 01:38 PM  
Sticky: Pentax K-01 Review Posted
Posted By Owltown
Replies: 88
Views: 50,638
Thank you for a superbly detailed review! Based on your comments and videos, I can tell that this is not a camera I'd invest in. Critical focus in all lighting conditions is essential. The lack of a proper viewfinder with full protection from ambient light relegates this camera to the point-and-shoot class IMHO. What benefit do you derive from being able to use all your high-dollar K-mount glass, if you cannot be assured of sharp focus each and every time? I shoot a lot of close-up work, using a K20D in manual focus mode most of the time, and get consistent results no matter where the light source is relative to the back of the camera. I also cannot understand the obsession manufacturers have with including video capability in still cameras. If I want to shoot video, I'll use a dedicated video camera. Don't make me pay for spurious video technology in my still camera -- give me a hooded electronic viewfinder instead!
Forum: Pentax K-01 02-03-2012, 03:36 PM  
Official Pentax K-01 Specifications Revealed
Posted By Owltown
Replies: 60
Views: 7,645
Hallelujah! Here's a DSLR-grade camera with a hot shoe! No more need to fire a built-in flash in master/slave mode to trigger a second flash .... just slip on the old Vivitar 285 with diffuser and fire away. It's about time all DSLR manufacturers recognized the need for either a hot shoe or a PC connection on pro-sumer grade cameras, not just on their $3K models.
Search took 0.05 seconds | Showing results 1 to 14 of 14

 
Forum Jump


All times are GMT -7. The time now is 11:15 AM. | See also: NikonForums.com, CanonForums.com part of our network of photo forums!
  • Red (Default)
  • Green
  • Gray
  • Dark
  • Dark Yellow
  • Dark Blue
  • Old Red
  • Old Green
  • Old Gray
  • Dial-Up Style
Hello! It's great to see you back on the forum! Have you considered joining the community?
register
Creating a FREE ACCOUNT takes under a minute, removes ads, and lets you post! [Dismiss]
Top