Pixalo Photography Community

Go Back   Pixalo Photography Community > Photography Forums > Cameras, Lenses and Accessories

Cameras, Lenses and Accessories: Discuss 400D focusing problem...Hi, First post (although I have been a reader for a little while) so hello all. I have done some ...
Welcome to the Pixalo Photography Community. As a Guest you are free to browse the site, but see what extras you get as a Member here.


Reply
 
LinkBack Thread Tools Display Modes
Old 30-03-2008, 13:48   #1 (permalink)
Forum Regular
 
Larne's Avatar
 
Join Date: Mar 2008
Location: Warrington, Cheshire, UK
Posts: 738
Larne has a spectacular aura aboutLarne has a spectacular aura aboutLarne has a spectacular aura aboutLarne has a spectacular aura aboutLarne has a spectacular aura aboutLarne has a spectacular aura aboutLarne has a spectacular aura aboutLarne has a spectacular aura about

Image editing O.K.
User's Gallery
Users Camera Equipment List
400D focusing problem

Hi,

First post (although I have been a reader for a little while) so hello all.

I have done some searching on my problem and didn't find anything specific but obviously I apologise in advance in case this is something that someone has already covered.

Okay, on with it. I have had a 400D for a while now, great camera and I like it a lot, but since I started playing with my images in Photoshop I have become aware that they are a bit soft. No major problem with that, I have been using the stock 18-55mm that comes with the kit I am happy consider that what I am running into are the limitations of the lens.

Digging through some of my gear the other day I found an EF 50mm f/1.8 lens that I must have had around 10 years so I thought I would give that a try and see how I got on. After returning from a day out with the family I was horrified to discover that every image I had shot was out of focus.

The light was poor so I had left the lens wide open at f/1.8 and for most all shots I was using spot focusing on the target's face then, holding the focus lock, recomposing and taking the picture. What was more noticeable was that not only was the face always blurred but that there would be some part of the picture that was closer to the camera that was always in very sharp focus.

This looked a lot like the camera was focusing just short of the actual selected target so I ran some experiments. Using some sections of tree trunk in the back garden I experimented with the 50mm and discovered that the focal plane (if that is the right term) appears to be just in front of the point where I am focusing. This is very apparent at f/1.8 but becomes much less apparent as the aperture gets smaller (as you would expect).

What I am not sure about is whether this is a problem with the 50mm (which is pretty old) or something more fundamental with the camera. With a max aperture of f/3.5 at 18mm on the 18-55mm it is hard to tell whether it is missing the focusing point, although my experiments make me suspect that it is.

I have had many Canon film cameras before and have never had cause to question the autofocus which has always been brilliant. Perhaps I am merely doing something wrong but if so I don't know what as I am doing the same as I always have in terms of focusing and composing shots.

Does anyone have any thoughts or suggestions? Is it just the lenses? I have a EF 28-135mm IS USM on the way so will be repeating the experiments with that when it arrives to see if I get any different results.

Thanks in advance for any comments.

Niall
Larne is offline  
Digg this Post!Add Post to del.icio.usBookmark Post in TechnoratiFurl this Post!
Reply With Quote
Old 30-03-2008, 14:24   #2 (permalink)
P-E
Part of the furniture
 
Join Date: Aug 2005
Location: Sheffield, S.Yorkshire UK
Posts: 12,250
P-E is a name known to allP-E is a name known to allP-E is a name known to allP-E is a name known to all
P-E is a name known to allP-E is a name known to allP-E is a name known to allP-E is a name known to allP-E is a name known to all

Image editing O.K.
User's Gallery
Users Camera Equipment List
Re: 400D focusing problem



I can only advise that if you google for the 'D70 focus chart' which you can print off and test your lenses.

I'm sure someone else will be along to help further
P-E is offline  
Digg this Post!Add Post to del.icio.usBookmark Post in TechnoratiFurl this Post!
Reply With Quote
Old 30-03-2008, 14:46   #3 (permalink)
Forum Regular
 
Chris H's Avatar
 
Join Date: Jan 2008
Location: UK
Posts: 995
Chris H is a jewel in the roughChris H is a jewel in the roughChris H is a jewel in the roughChris H is a jewel in the roughChris H is a jewel in the roughChris H is a jewel in the roughChris H is a jewel in the roughChris H is a jewel in the roughChris H is a jewel in the roughChris H is a jewel in the roughChris H is a jewel in the roughChris H is a jewel in the rough

Image editing O.K.
User's Gallery
Users Camera Equipment List
Re: 400D focusing problem

Have a read of this thread


http://www.pixalo.com/community/gene...00d-22622.html
Chris H is offline  
Digg this Post!Add Post to del.icio.usBookmark Post in TechnoratiFurl this Post!
Reply With Quote
Old 30-03-2008, 15:46   #4 (permalink)
Pixalo Crew
 
dabhand16's Avatar
 
Join Date: Jun 2006
Location: Dunstable Bedfordshire UK
Posts: 30,261
dabhand16 is a glorious beacon of lightdabhand16 is a glorious beacon of lightdabhand16 is a glorious beacon of light
dabhand16 is a glorious beacon of lightdabhand16 is a glorious beacon of lightdabhand16 is a glorious beacon of lightdabhand16 is a glorious beacon of lightdabhand16 is a glorious beacon of light

Image editing O.K.
User's Gallery
Users Camera Equipment List
Re: 400D focusing problem

Also this might be of interest too.
dabhand16 is offline  
Digg this Post!Add Post to del.icio.usBookmark Post in TechnoratiFurl this Post!
Reply With Quote
Old 30-03-2008, 20:26   #5 (permalink)
Forum Regular
 
Larne's Avatar
 
Join Date: Mar 2008
Location: Warrington, Cheshire, UK
Posts: 738
Larne has a spectacular aura aboutLarne has a spectacular aura aboutLarne has a spectacular aura aboutLarne has a spectacular aura aboutLarne has a spectacular aura aboutLarne has a spectacular aura aboutLarne has a spectacular aura aboutLarne has a spectacular aura about

Image editing O.K.
User's Gallery
Users Camera Equipment List
Re: 400D focusing problem

Hello again.

Thanks for the prompt and informative responses.

The D70 focus chart is an excellent idea. Using that the line where I get sharpest focus on my 50mm is the one marked 10mm in front of the focus point. I tried it on f/1.8 and f/2.8 and I get the same result in both cases. So it looks to me rather like the lens is past it - it is old (it was second hand when I bought it a decade ago) and today I actually had it lock up at f/2.0 and cause the camera to shut down with an Er99 so I am guessing I need look no further.

Results on the EF-S 17-55mm are much more encouraging. At 17mm f/3.5 the target is perfectly sharp with the depth of field extending approx 1/3 in front of the point and 2/3 behind (as I understand it should be). At 55mm f/5.6 it is perfectly in focus, to the extent that I can actually see the texture on the paper. Sure it is soft but a quick run through the Unsharp Mask filter on Photoshop elements turns it nice and crisp.

Thanks again for the help. At least now I know the problem is the 50mm lens and I will be disposing it once I work out the best way of recycling it. I will run the same tests on the EF 28-135 when it arrives and hopefully they will be positive.

Cheers,

Niall
Larne is offline  
Digg this Post!Add Post to del.icio.usBookmark Post in TechnoratiFurl this Post!
Reply With Quote
Old 30-03-2008, 20:42   #6 (permalink)
Pixalo Crew
 
Markulous's Avatar
 
Join Date: Jul 2006
Location: Peak District
Posts: 19,640
Markulous is a jewel in the rough
Markulous is a jewel in the roughMarkulous is a jewel in the roughMarkulous is a jewel in the roughMarkulous is a jewel in the roughMarkulous is a jewel in the roughMarkulous is a jewel in the rough

Image editing O.K.
User's Gallery
Users Camera Equipment List
Re: 400D focusing problem

You could always use that 50mm as a manual focus lens (as per the older M42 lenses) - oh, and to Pixalo
Markulous is offline  
Digg this Post!Add Post to del.icio.usBookmark Post in TechnoratiFurl this Post!
Reply With Quote
Reply

Thread Tools
Display Modes

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 On
Pingbacks are On
Refbacks are On


Similar Threads
Thread Thread Starter Forum Replies Last Post
focusing/adjusting for glasses/or not/help! Ruthiebabe General photography questions and answers 12 22-10-2007 17:57
Canon 400d and 400d Kiss x? rodger1138 Which Camera Should I Buy? 5 31-08-2007 16:48
focusing prob viki Cameras, Lenses and Accessories 4 29-03-2007 15:30
IF (Internal Focusing)? ilkand Cameras, Lenses and Accessories 26 10-01-2006 12:25


All times are GMT +1. The time now is 14:24.


vBulletin Copyright ©2000 - 2017, Jelsoft Enterprises Ltd.
ReviewPost & PhotoPost vB3 Enhanced, Copyright 2003-2014 All Enthusiast, Inc.
SEO by vBSEO 3.3.0
Copyright © 2006 - 2017 Pixalo.com

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197