Pages: [1]   Go Down

Author Topic: Blurry imace follow-up  (Read 4041 times)

wmchauncey

  • Sr. Member
  • ****
  • Offline Offline
  • Posts: 793
Blurry imace follow-up
« on: June 15, 2007, 08:04:03 am »

You may remember my complaint about RAW shooting a cell tower 1/2 mile away and getting blurry images, esp. at 100% in ACR using cheap Sigma glass.  Well, I repeated the experiment using a Canon 17-85 f/4-5.5 IS on my Rebel xti.  It was like the lights were turned on.  Throughout the setting range, the Canon stayed clear to well over 100%.  Pixelating, that had occured at 200% with the Sigma, didn't occur until 400% with the Canon glass.

Can this problem be fixed except by pouring more dollars into the glass,  I'm trying to avoid buying the Canon 70-300 f/4-5.6 IS as well as the one listed above?
Logged
The things you do for yourself die with

kal

  • Jr. Member
  • **
  • Offline Offline
  • Posts: 63
    • http://fotonordest.blogspot.com
Blurry imace follow-up
« Reply #1 on: June 15, 2007, 10:38:01 am »

Quote
You may remember my complaint about RAW shooting a cell tower 1/2 mile away and getting blurry images, esp. at 100% in ACR using cheap Sigma glass.  Well, I repeated the experiment using a Canon 17-85 f/4-5.5 IS on my Rebel xti.  It was like the lights were turned on.  Throughout the setting range, the Canon stayed clear to well over 100%.  Pixelating, that had occured at 200% with the Sigma, didn't occur until 400% with the Canon glass.

Can this problem be fixed except by pouring more dollars into the glass,  I'm trying to avoid buying the Canon 70-300 f/4-5.6 IS as well as the one listed above?
[a href=\"index.php?act=findpost&pid=122956\"][{POST_SNAPBACK}][/a]

Well, you could buy second-hand glass... or you could stop looking at your photos at 400%. Assuming your monitor is capable of 96dpi, a 400% zoom is like looking at a 24dpi print. Assuming you use the full 3888x2592 resolution your camera is capable of, this means making a 4x2.7m print... are you really going that large?

(sort-of joking, I'm really happy I've spent quite a lot of euros on good Canon glass)
Logged
Piero
[url=http://fotonordest.blogspot.c

DarkPenguin

  • Guest
Blurry imace follow-up
« Reply #2 on: June 15, 2007, 11:26:33 am »

Are you sure it isn't the IS that's saving you?

Oh, and almost all lenses have an operating window where they are very good.  Even cheap ones.  (The Canon 18-55 is nice from f8-f11 as you get closer to 55mm.)  The window may be small but if you find that window and can stick to using it.....
« Last Edit: June 15, 2007, 11:29:27 am by DarkPenguin »
Logged

wmchauncey

  • Sr. Member
  • ****
  • Offline Offline
  • Posts: 793
Blurry imace follow-up
« Reply #3 on: June 15, 2007, 12:13:42 pm »

Quote
Are you sure it isn't the IS that's saving you?

Oh, and almost all lenses have an operating window where they are very good.  Even cheap ones.  (The Canon 18-55 is nice from f8-f11 as you get closer to 55mm.)  The window may be small but if you find that window and can stick to using it.....
[a href=\"index.php?act=findpost&pid=122991\"][{POST_SNAPBACK}][/a]
Logged
The things you do for yourself die with

wmchauncey

  • Sr. Member
  • ****
  • Offline Offline
  • Posts: 793
Blurry imace follow-up
« Reply #4 on: June 15, 2007, 12:17:08 pm »

Quote
[a href=\"index.php?act=findpost&pid=122997\"][{POST_SNAPBACK}][/a]
oops
Tripod used in all tests-I raise the magnification to see how much cropping I can get away with as well as checking glass quality
Logged
The things you do for yourself die with
Pages: [1]   Go Up