Go Back   Steve's Digicams Forums > Digital SLR and Interchangeable Lens Cameras > Sony Alpha dSLR / Konica Minolta dSLR, Sony SLT

Reply
 
Thread Tools Search this Thread
Old Mar 24, 2010, 9:58 PM   #1
Senior Member
 
Join Date: Jan 2007
Location: Decatur, GA
Posts: 2,053
Default Sima 50-150 sand Sony Bodies

title of post should read Sigma not Sima. Sorry for typo

On a possible Tiip off I got from Tcav I want to ask if anyone is having any issues with using the Sima 50-150mm f/2.8 on any Sony Body. The issue I am having is that I am getting dirty mirror and sensor and my AF is starting to not work right. Seems every time I change lenses it starts to creep in and something that Tcav said that toip me off is that their maybe an air issue with the 50 -150 as moist of the pictures around smoke are taken with the 50-150 and I have taken a good deal lately. IUssue started about 7 weeks ago, although been using the 50-150 for about 14 weeks. Sony tells me the dirty sensor has something to do with the AF acting up. I have been having to clean the sensor once a week. I might be going back to a high end Point and Shoot/bridge camera with a built in lens soon. Its too the point on my A250 that 1 in ever 3 pictures is out of wack/focus and not 100% sharp.

Anyone have similar experiences, how did you resolve it etc. Any repair advise and how to keep this from happening again......

dave
Photo 5 is offline   Reply With Quote
Sponsored Links
Old Mar 25, 2010, 8:11 AM   #2
Senior Member
 
TCav's Avatar
 
Join Date: Sep 2005
Location: Washington, DC, Metro Area, Maryland
Posts: 13,543
Default

I think that the 50-150 may be acting as a bellows, sucking in air as you zoom. That problem won't necessarily go away if you switch to a high-end P&S. Though it may take a little longer, when it does happen, the same dust particles will have a bigger impact on your photos (because of the smaller sensor size), and you won't be able to clean it yourself.

Let's face it. You take photos in some pretty nasty places, and it appears that all the typical precautions aren't enough.
__________________
  • The lens is the thing.
  • 'Full Frame' is the new 'Medium Format'.
  • "One good test is worth a thousand expert opinions." - Tex Johnston, Boeing 707 test pilot.

Last edited by TCav; Mar 25, 2010 at 8:13 AM.
TCav is offline   Reply With Quote
Old Mar 25, 2010, 8:41 AM   #3
Senior Member
 
Join Date: Jan 2007
Location: Decatur, GA
Posts: 2,053
Default

I need to talk to the people that photography the military in the deserts and Iraq etc and find out what they do. I can safely say I had a Fuji S9100 for 18 months and never had single issue with it, dust or image quality

dave
Photo 5 is offline   Reply With Quote
Old Mar 25, 2010, 11:39 AM   #4
Senior Member
 
NewsyL's Avatar
 
Join Date: Jul 2004
Location: Vancouver, BC Canada
Posts: 231
Default

The 50-150 is internal zooming so I'm wondering how the "bellows effect" can come into play.

I was going to suggest the 70-200 as it is internal zooming and I've not read of any bellows effect issues with it.

I have that bellows effect issue (I believe) with my Sigma 50-500 but the frequency of cleaning the sensor has become less in recent months which leads me to believe that some of the issues I had early on were from internally generated debris. When I first acquired my A700 I was having to wet clean the sensor every two weeks for the first 3 or 4 months. I suspect that some of the blobs I was seeing were lubricant.

If environmental sealing is critical, I would look to Pentax as from what I understand in my limited reading is that their bodies (not sure about bottom end) have superb weather sealing as do a number of their lens.

.
NewsyL is offline   Reply With Quote
Old Mar 25, 2010, 9:03 PM   #5
Senior Member
 
Join Date: Jan 2007
Location: Decatur, GA
Posts: 2,053
Default

Thanks right now I got the Sony A200 and the 28 - 300 lens working just fine..... tomorrow will try the 50 - 150mm

dave
Photo 5 is offline   Reply With Quote
Old Mar 28, 2010, 10:42 PM   #6
Senior Member
 
Join Date: Jan 2007
Location: Decatur, GA
Posts: 2,053
Default

Update (sorry this is so long):

Thanks for all the help/advise people have offered to me. It seems that like TCAV said their is an issue with the 50 - 150mm being a bellow. Also from what three separate sources told me the sensor has gotten dust past the lock up mirror from normal use in the elements of smoke/fire etc. Even though I tend to change the lenses in the trunk of my car they claim just and smoke particles from my stored fire gear their is not helping.....

The cheapest estimate I got was for $90 to clean the entire inside of the camera and that does not guarantee that will fix the problem since the AF focal motor/assembly may be damaged....... Also once it is clean/working how long until it happens again.

Did a lot of soul searching yesterday and today. I have the Olympus 1050SW that is working but only has a 3x zoom, the Sony A200 is working but it focuses a little slower than I'd like or think it should......

I also still have an old 4MP Olympus with a 10x zoom but it has an issue with the view finder and all the images look a solid purple but they come out ok when downloaded. 4MP is too small for the newspaper to get 1/2 and full page shots......

I also looked back on older cameras I had and remember how much I loved my Fuji S9100 the 18 months I used it. I also thought about weather to get another Sony D-SLR or another D-SLR of any brand. I talked to both employers and neither said the camera has to be a D-SLR just it has to be 8MP or higher and take good images.

So at this point I am using the Sony A200 and the pocket camera and looking for a new camera. I have a major paying gig lined up with UVA hospital the last weekend of May where I need to provide them with photos on DVDs at 8MP or higher resolution. So I need to may sure by then I have this resolved. I do have approx $750 I can spend at this point on whatever I end up doing (I will re-coop that amount from the UVA gig).

I am seriously looking at the Fuji HS10, another slightly older Fuji, trying to find a new or used Fuji S9100 that I shot with in late 2007-early 2009 and a couple of other cameras that have 10x zoom or greater. I am reading everything I can find on them on the internet and the board here. My hope is if I get a camera with a built in lens I will not have the AF/dust/smoke issue again. I DID NOT have a single issue with the AF focus or smoke etc with the Fuji S9100 in the entire time I used it. The lens did fog up a few times.

So before you ask why did I move to a D-SLR
a) to get more shots per battery -- no more switching out batteries
b.) better lower light photos
c.) thinking it would magically improve my sport photos (which I learned it didn't even though I could shoot more frames faster)......

So why move backwards
- I am hoping to stay in the high end bridge camera family and get the best camera I can afford in that market to try keep as much of the quality as I can and not have lens changing issues.
- Also I miss being able to shoot a quick 640 x 480 video clip without changing cameras

I will report back when I decide what to do.....

dave
Photo 5 is offline   Reply With Quote
Old Mar 29, 2010, 7:21 AM   #7
Senior Member
 
TCav's Avatar
 
Join Date: Sep 2005
Location: Washington, DC, Metro Area, Maryland
Posts: 13,543
Default

First, I don't think switching to a P&S, even a high end one, would prevent the same kind of thing from happening again. You were able to avoid the problem with your S9100, but that's not a guarantee that it won't happen with a newer model. I think you should seriously look at something that's waterproof, or at lease weatherproof.

Second, I think that a Pentax K-x with their weatherproof lenses might be a better alternative than a P&S, even a weatherproof P&S. It can shoot at higher ISO settings using the smaller apertures that are typical of P&S cameras, as well as Pentax' weatherproof lenses.
__________________
  • The lens is the thing.
  • 'Full Frame' is the new 'Medium Format'.
  • "One good test is worth a thousand expert opinions." - Tex Johnston, Boeing 707 test pilot.
TCav is offline   Reply With Quote
Old Mar 29, 2010, 9:06 AM   #8
Senior Member
 
Join Date: Jan 2007
Location: Decatur, GA
Posts: 2,053
Default

Thanks for advice TCav I do have a weatherproof/waterproof OLympus but the zoom is only 3x which is not enough to do me much good.

dave
Photo 5 is offline   Reply With Quote
Old Mar 31, 2010, 11:19 AM   #9
Administrator
 
Join Date: Jun 2003
Location: Savannah, GA (USA)
Posts: 22,378
Default

Dave:

I'm not convinced that your issues are all smoke related. Some of your previous photos appeared to have issues due to shutter speeds being too slow causing blurry photos, especially those at night. IOW, the conditions were dark enough that you really needed to be using a high powered external flash. Also, any camera is going to have focus issues at night in darker conditions, even if some of your issues are focus versus shutter speed related.

So, you may be going "from the frying pan into the fire", by moving from a dSLR model to a point and shoot model with slower and less sensitive contrast detect AF (not to mention lower usable ISO speeds for keeping your shutter speeds fast enough to reduce blur). Also, as already mentioned, you can clean the sensor yourself with a dSLR. With a non-dSLR model, a trip back to the manufacturer may be needed if you get particles on your sensor.
JimC is offline   Reply With Quote
Old Mar 31, 2010, 12:21 PM   #10
Senior Member
 
penolta's Avatar
 
Join Date: Apr 2007
Location: California USA
Posts: 5,206
Default

Quote:
Originally Posted by TCav View Post

Second, I think that a Pentax K-x with their weatherproof lenses might be a better alternative than a P&S, even a weatherproof P&S. It can shoot at higher ISO settings using the smaller apertures that are typical of P&S cameras, as well as Pentax' weatherproof lenses.
In addition to the above, the newer Pentax bodies have self-cleaning sensors. Provided that the particles are not particularly sticky, they will be shaken off every time the camera is turned on.

There are also some underwater cases or flexible covers that might be useful for any number of cameras.
__________________
.
.
If life brings you lemons, you can make lemonade.

Last edited by penolta; Mar 31, 2010 at 12:25 PM.
penolta is offline   Reply With Quote
 
Reply


Thread Tools Search this Thread
Search this Thread:

Advanced Search

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off



All times are GMT -5. The time now is 1:25 AM.