Forgot Password
Pentax Camera Forums Home
 

Reply
Show Printable Version Search this Thread
02-02-2009, 06:45 AM   #16
Pentaxian
Lowell Goudge's Avatar

Join Date: Jan 2007
Location: Toronto
Photos: Gallery | Albums
Posts: 15,400
QuoteOriginally posted by fgpinarli Quote
Hi. My K20 D underexpose with M 100mm macro and K 135/2.5 with wider exposure, f:4 and f:2.5 respectively. When I stop down the lenses, the exposure become correct without compensation. I use them im M mode metering with the green button. Related the use of the central part of the lenses? Any explanation? Thank you
try this

https://www.pentaxforums.com/forums/241716-post69.html

it has been well documented, i think you will find it will also over expose beyond F5.6

the bottom line, and I made this point in an earlier post, as have about 6 other people, is that you need to check how your equipment performs.

It is not all that hard, even if you have a ton of lenses.

02-09-2009, 03:56 PM   #17
Junior Member




Join Date: Nov 2008
Location: Taunton, UK
Posts: 48
Yes I know in practice we have to know our equipment and adjust for its failings.

However I am astounded that when we buy an expensive modern piece of computerised equipment with multiple light metering options that we should have to accept that this equipment cannot apparently do simple calculations like double the exposure for each stop adjustment away from full aperture.

Non-linear screen responses are cited as responsible, but if true, can this not be programmed in to the calculation?

It just seems amazing to me that you can have muli-segment, center weighted or spot metering and then at the end of the day you have to manually assess and correct the result, or even worse, always make the same correction that the camera is unable to do for itself.
02-09-2009, 05:15 PM   #18
Pentaxian
Lowell Goudge's Avatar

Join Date: Jan 2007
Location: Toronto
Photos: Gallery | Albums
Posts: 15,400
QuoteOriginally posted by kevbirder Quote
Yes I know in practice we have to know our equipment and adjust for its failings.

However I am astounded that when we buy an expensive modern piece of computerised equipment with multiple light metering options that we should have to accept that this equipment cannot apparently do simple calculations like double the exposure for each stop adjustment away from full aperture.

Non-linear screen responses are cited as responsible, but if true, can this not be programmed in to the calculation?
it is, and this is why A series lenses meter much better than earlier ones,
QuoteQuote:

It just seems amazing to me that you can have muli-segment, center weighted or spot metering and then at the end of the day you have to manually assess and correct the result, or even worse, always make the same correction that the camera is unable to do for itself.
the issue is people want all things, better brighter view finders easier to see throug, which causes them to make viewing screens that have more depth of field than the images the lens gives, and makes them brighter with the lower cost slower lenses. Remember, most kit lenses and low cost zooms are F4-5.6, where as in the bad old days of film, even the cheapest kit 50 was F2.0
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, exposure, lens, lenses, meter, photography
Thread Tools Search this Thread
Search this Thread:

Advanced Search


Similar Threads
Thread Thread Starter Forum Replies Last Post
K10D, SMC-M lenses, stop-down metering J2R Pentax DSLR Discussion 10 05-22-2009 03:26 AM
k10D metering with M lenses in M mode - K200D doing a better job w/ Green button mrpackerguy Pentax DSLR Discussion 8 10-03-2008 11:53 AM
M lenses and metering pentagor Pentax SLR Lens Discussion 1 05-21-2008 01:50 PM
K10D, manual lenses, and metering vinzer Pentax DSLR Discussion 40 06-30-2007 07:54 AM
Lenses and Metering arbutusq Pentax SLR Lens Discussion 1 04-16-2007 12:25 PM



All times are GMT -7. The time now is 04:32 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