Cor From South Africa, joined Mar 2007, 14 posts, RR: 0 Posted (4 years 3 weeks 3 days 10 hours ago) and read 2054 times:
I need help.
I use a canon 350d with sigma 70-300mm lens. I just don't seem to get sharp focus. I use 5.6 aperture mostly at telephoto range. Manual focus and auto focus seem more or less the same.
I try to get shots of planes passing over my house. Obviously I use no tripod for this. Can anybody give me some pointers?
JohnKrist From Sweden, joined Jan 2005, 1340 posts, RR: 5 Reply 2, posted (4 years 3 weeks 3 days 9 hours ago) and read 2042 times:
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Getting good pics of planes passing is hard, and that Sigma is rather soft at 300mm which also affects your images. As Othic said, keep the aperture at 8-11. And it's also hard to keep that small dot that the aircraft is, in the focus point (use center focus point only). I find it a little easier to hunt the contrail just behind the aircraft. And shoot series, odds are one is good if you shoot a series of 6-8 shots.
7D, 17-40 F4 L, 70-200 F2.8 L IS, EF 1.4x II, EF 2x III, Metz 58-AF1
Stulli From Germany, joined Mar 2009, 48 posts, RR: 0 Reply 3, posted (4 years 3 weeks 3 days 7 hours ago) and read 1973 times:
Especially relatively cheap lenses are best at medium apertures of 8-11, 5.6 is completely open aperture, I guess, just forget about that if it's not a really good, which sadly means really expensive lens.
Another idea: Is your lens maybe dirty or scratched? Or maybe dropped the camera, so the focussing is maladjusted (don't know if this is the correct word, but you might know what I mean).
Hernan From United States of America, joined Oct 2005, 93 posts, RR: 0 Reply 4, posted (4 years 3 weeks 3 days 6 hours ago) and read 1967 times:
I totally agree, I have the Sigma 55-200 and it is the sharpest in the area of f/8-f/11, I liked the Sigma so well that I recently bought the 28-105, very good medium range zoom, great walkaround.
JakTrax From United Kingdom, joined Jun 2005, 4779 posts, RR: 8 Reply 5, posted (4 years 3 weeks 2 days 21 hours ago) and read 1894 times:
From my experience the budget Sigma 70-300 is a particularly soft lens, especially above about 200mm. Closing the aperture down (making sure to shoot in Av mode) to F8 or smaller (higher as the numbers go) as others have said will improve things but if you want super-sharp images you're going to have to invest in better glass (I'm afraid!).
Cvervais From United States of America, joined Sep 2003, 602 posts, RR: 3 Reply 6, posted (4 years 3 weeks 2 days 20 hours ago) and read 1886 times:
When I was starting out I too was wondering why the images from my 100-400 f/4.5-5.6 Canon lens would come out soft. It's a professional series lens and I was dumbfounded at the results I was getting.
Until.......
I realized I was gripping the lens at the focus ring! On this lens even if you have it set to autofocus the ring will still adjust the focus. So when I'd pan or zoom in or out (it's a telescoping lens) I would bump the focus off enough to create a less than sharp image. Once I started holding it properly (not on the focus ring) I was able to get amazingly sharp images out of it....
RonS From United States of America, joined Feb 2009, 761 posts, RR: 24 Reply 7, posted (4 years 3 weeks 2 days 19 hours ago) and read 1880 times:
Actually that is a good point not to touch the focus ring. Along those lines, keep a steady hand. I'm at fault often slightly moving the camera when I shoot!
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