Forgot Password
Pentax Camera Forums Home
 

Reply
Show Printable Version Search this Thread
01-21-2007, 03:22 PM   #1
Forum Member




Join Date: Jan 2007
Location: burlington ontario canada
Posts: 62
overexposure using A series lens

I have just purchased two lenses, a 50mm 1.7 and 28mm 2.8 , both smc Pentax-A lenses. I was under the impression they would work as well as my 18-55mm kit lens on my newly aquired K100D ( using manual focus).
In both cases though, after dialing in the appropriate focal length I am getting photos well overexposed..in fact so bad that even the largest setting using the EV compensation won't correct it enough.
Am I doing something wrong?...I am using the P mode but AV or TV modes don't make a difference. I am of course using the Green "A" on both of the lenses.
your imput would be gratefully accepted and appreciated.

01-21-2007, 03:49 PM   #2
Veteran Member
-=JoN=-'s Avatar

Join Date: Nov 2006
Location: NYC
Posts: 1,000
you have any shot data?
01-21-2007, 04:07 PM   #3
Forum Member




Join Date: Jan 2007
Location: burlington ontario canada
Posts: 62
Original Poster
QuoteOriginally posted by -=JoN=- Quote
you have any shot data?
I'm sorry, excuse my ignorance but I don't understand your question.
I just tried the lenses from my balcony ...got the overexposure using both (using p mode) ..then changed lenses to my two Pentax DA lenses to get perfectly exposed photos???....Incidentally I tried the "scene" mode of "surf and snow"....and the results were even more overexposed...strange!
Thanks for the comeback.
01-21-2007, 04:10 PM   #4
Forum Member




Join Date: Jan 2007
Location: burlington ontario canada
Posts: 62
Original Poster
QuoteOriginally posted by trev99 Quote
I'm sorry, excuse my ignorance but I don't understand your question.
I just tried the lenses from my balcony ...got the overexposure using both (using p mode) ..then changed lenses to my two Pentax DA lenses to get perfectly exposed photos???....Incidentally I tried the "scene" mode of "surf and snow"....and the results were even more overexposed...strange!
Thanks for the comeback.
Sorry I forgot to mention that there is some snow on the ground ...hence the "surf@snow choice.

01-21-2007, 04:32 PM   #5
Veteran Member
-=JoN=-'s Avatar

Join Date: Nov 2006
Location: NYC
Posts: 1,000
sorry, shot data, meaning settings, (ie, shutter speed, etc, etc..)
or better yet, post a pic, so we can see what's going on.

do you have the lens in aperture ring in the "a" position...(Not sure if you can set the k100 to shoot if the lens is not in "a" position)
01-21-2007, 04:40 PM   #6
Veteran Member
Alvin's Avatar

Join Date: Dec 2006
Location: Mississauga, Ontario, Canada
Photos: Gallery
Posts: 2,530
QuoteOriginally posted by -=JoN=- Quote
Not sure if you can set the k100 to shoot if the lens is not in "a" position
Jon - it's possible, just have to be in Manual mode. Posted directions earlier today over here.

https://www.pentaxforums.com/forums/welcomes-introductions/2483-hi-wyoming.html

Trev. I'm a new K100D user but I haven't used an A series lens yet. I am tooling with these two K-mount lenses that are totally manual and I'm learning how to use them. Hope both Jon and I can help. Please post a picture - if you are unsure, email it over to me (alvin.villanueva"AT"hotmail.com) and I can put it up here for you.

Cheers!
01-21-2007, 05:07 PM   #7
Forum Member




Join Date: Jan 2007
Location: burlington ontario canada
Posts: 62
Original Poster
Hi Alvin, I know that when using some of the earlier Pentax lenses you have to use the manual mode on the K100D but the Pentax-A setries lens should work just fine using all modes with the only difference (from using DA lenses) of having to manually focus on a subject....I am not getting a correct exposure ie. the AE on the camera isnt working (my understanding is that with the A series of lenses this should'nt be a problem.
I could send sample photos but it would'nt help much since you would just see an overexposed shot or shots. My DA lenses (including my kit lens workes fine using the same settings).. but thank you for your offer and your help.
Jon...I AM using the A setting on the aperture ring.
01-21-2007, 05:10 PM   #8
Veteran Member
-=JoN=-'s Avatar

Join Date: Nov 2006
Location: NYC
Posts: 1,000
didnt mean to be a smart ass with that question, but i was just asking or pointing out the obvious since that's what usually gets overlooked...

we want to see the photo for the exif data, and not the overexposed shot.

01-21-2007, 05:19 PM   #9
Veteran Member
Alvin's Avatar

Join Date: Dec 2006
Location: Mississauga, Ontario, Canada
Photos: Gallery
Posts: 2,530
Doing some brainstorming here.

AutoPict (Green), P , Av and Tv modes. If you pushed and held Av button while turning the thumbwheel look in the viewfinder you will notice the number to the very right go -2.0 through to 2.0. Make it 0.0

Hope you still have the card in your camera. Press the Play button to review your picture, go to the picture that was overexposed. Press Info twice. Now at this screen immediately under the picture, you will see shutter speed, Aperture value (FStop) and exposure value (EV). if EV was not 0.0 but some positive value, that could be your problem.
01-21-2007, 05:25 PM   #10
Veteran Member
Alvin's Avatar

Join Date: Dec 2006
Location: Mississauga, Ontario, Canada
Photos: Gallery
Posts: 2,530
QuoteOriginally posted by trev99 Quote
I could send sample photos but it would'nt help much since you would just see an overexposed shot or shots. My DA lenses (including my kit lens workes fine using the same settings).. but thank you for your offer and your help.
Trev, the files usually have data stored on them (known as EXIF data, or some people call it shot data). The camera writes the settings it used when taking the photo. It helps a ton when troubleshooting.

If you are using windows, right click on your picture file, click properties, click Advanced. You will see the info there almost the same as if you pressed info twice on your camera when reviewing the picture.
01-21-2007, 07:35 PM   #11
Forum Member




Join Date: Jan 2007
Location: burlington ontario canada
Posts: 62
Original Poster
Ah! yes Jon I understand...you'll have to excuse me , I have used a film SLR for years but this is my first DSLR and I have only owned it a week.....A whole new ball game lol.(although I do own a digital P@S)
Also I'm not sure how to include a photo (I'm 66 and although I've been using computers for 6 years I'm not very savvy on some things).
Thanks for your help.
01-21-2007, 07:45 PM   #12
Forum Member




Join Date: Jan 2007
Location: burlington ontario canada
Posts: 62
Original Poster
Thanks for your imput Alvin. I anitially tried using the av button and thumb wheel combination although I usually leave it at the 00 setting and it did'nt help.
What I can't understand is if my regular DA lenses are giving me perfect exposured pictures; why doesn't these two Penytax-A lenses do the same thing using the same settings? If it was just one lens I would think it was a dud , but two? nah!
01-21-2007, 07:47 PM   #13
Veteran Member




Join Date: Sep 2006
Location: Virginia Beach VA USA
Photos: Gallery
Posts: 1,364
Trev,
They should work fine. Have you checked the aperture mechanisms in the lens to make sure they are working properly? Manipulate the actuation lever and see if the aperture is closing all the way, and that it is "snapping" shut and open, not hanging up.

Other than ensuring you are in the "A" position, I can't think of any other reason your exposures are off.

-Alan
01-21-2007, 07:50 PM   #14
Forum Member




Join Date: Jan 2007
Location: burlington ontario canada
Posts: 62
Original Poster
Oh yes ..and unfortunately I deleted the photos and it's too late for daytime shots...maybe tomorrow.... using your advice to do a check.
thank you guys for trying to help me out, appreciate it.
01-21-2007, 08:01 PM   #15
Forum Member




Join Date: Jan 2007
Location: burlington ontario canada
Posts: 62
Original Poster
Hi Alan, I am definately aligning the A correctly on both aperture rings on the two lenses and I did the aperture test...they are working fine.
This is frustrating. I will have to take more photos under different conditions tomorrow (my day off).
I purposely bought the A lenses instead of the M series so all I had to worry about was going to manual focus with everything else being the same as my kit lens.
Reply

Bookmarks
  • Submit Thread to Facebook Facebook
  • Submit Thread to Twitter Twitter
  • Submit Thread to Digg Digg
Tags - Make this thread easier to find by adding keywords to it!
camera, dslr, lens, lenses, photography
Thread Tools Search this Thread
Search this Thread:

Advanced Search


Similar Threads
Thread Thread Starter Forum Replies Last Post
DA* SDM lens overexposure on a K5 - The moral is "don't panic." Delgado Pentax K-5 7 12-26-2010 05:19 PM
K20D overexposure billmcf Pentax DSLR Discussion 5 08-25-2010 06:36 AM
K-x overexposure? kevingt01 Pentax DSLR Discussion 5 05-17-2010 12:45 AM
consistant overexposure dougmc Pentax Compact Cameras 3 04-21-2010 12:46 AM
DA-series vs A-series lens .. does it make a diference on a dSLR? dresden_phoenix Pentax DSLR Discussion 16 05-03-2008 03:56 PM



All times are GMT -7. The time now is 11:33 PM. | 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