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aaronw1986

macrumors 68030
Original poster
Oct 31, 2006
2,622
10
I think my new lens is defective. So far I have not been happy with the results from it. After looking at others pictures taken with this lens and reading about it, something does not seem right. I am using it on a D40, so it is supposed to be using essentially the 'best' part of the lens. Pictures seem blurry, and only focused in one exact spot. Some may say it has to do with the user, but I've gotten many good shots with my 55-200 and have always been satisfied. Attached are some images showing what I am talking about. Thanks for any advice.

3741410206_a2f01ed8d1_b.jpg



3740617843_fd26123ae9_b.jpg


3741181837_50d0891d78_b.jpg
 

iBookG4user

macrumors 604
Jun 27, 2006
6,595
2
Seattle, WA
What shutter speed are you using to take the pictures? Since it is a longer focal length lens you'll need to use a faster shutter speed than you would with a wider lens. Typically you'll want to have a shutter speed of 1/(focal length), ie at 300mm you'll want to use a shutter speed of at least 1/320 second :)
 

compuwar

macrumors 601
Oct 5, 2006
4,717
2
Northern/Central VA
Some may say it has to do with the user, but I've gotten many good shots with my 55-200 and have always been satisfied.

It's really easy to see if it's user error. Put the camera on a sturdy tripod, aim at a well-lit and high-contrast target, focus manually using the "in focus" indicator, and take a picture. If it's soft and you're sure you used a stable platform, then it's the lens, if not, it's more likely to be the user. Repeat the test in bright light with VR on and handheld (that is light that'll give you at least 1/500th of a second.) If that's also sharp, then the source of the problem is definitely between the viewfinder and the ground. If not, then you'll know if it's VR or the lens itself.

Paul
 

aaronw1986

macrumors 68030
Original poster
Oct 31, 2006
2,622
10
What shutter speed are you using to take the pictures? Since it is a longer focal length lens you'll need to use a faster shutter speed than you would with a wider lens. Typically you'll want to have a shutter speed of 1/(focal length), ie at 300mm you'll want to use a shutter speed of at least 1/320 second :)

pic 1: 1/60
pic 2: 1/160
pic 3:1/320

I have a monopod I can use tomorrow. I was hoping to use this lens mostly handheld, so it will be a problem if these are the results I will be getting.
 

iBookG4user

macrumors 604
Jun 27, 2006
6,595
2
Seattle, WA
pic 1: 1/60
pic 2: 1/160
pic 3:1/320

I have a monopod I can use tomorrow. I was hoping to use this lens mostly handheld, so it will be a problem if these are the results I will be getting.

Yeah, those shutter speeds are a bit on the slow side. You should bump up the ISO some more and then try again, as the minimum you should be shooting at handheld is 1/320.
 

iBookG4user

macrumors 604
Jun 27, 2006
6,595
2
Seattle, WA
It's generally 1/EFL, so on a D40 it's more like 1/500ish for a handheld shot at 300mm.

Well, if you wanted to get technical... The camera is just cropping what the lens sees, so it is still a 300mm lens and it would be 1/320. But the faster the shutter speed the better, so you could go with that :p
 

telecomm

macrumors 65816
Nov 30, 2003
1,387
28
Rome
Well, if you wanted to get technical... The camera is just cropping what the lens sees, so it is still a 300mm lens and it would be 1/320. But the faster the shutter speed the better, so you could go with that :p

Yes, it's just cropping with the lens, but what's important is the relative percentage of movement.

Let's say shake causes 2 pixels of blur up/down. That's a greater percentage of the image height on a cropped sensor than on a full-frame sensor, hence the blur would be less acceptable on a cropped sensor.

Edit: Since this is a VR lens, the OP should gain an extra stop or two, but I would think this is a lens that's best used tripod/monopod rather than handheld.
 

aaronw1986

macrumors 68030
Original poster
Oct 31, 2006
2,622
10
I think the problem have have been a cheap UV filter. I've used on on my 55-200 vr lens without issue, but have been doing some reading that the 7-300mm is picky. What would be a good filter for this lens that would not distort image quality?
 

GoCubsGo

macrumors Nehalem
Feb 19, 2005
35,742
153
I think the problem have have been a cheap UV filter. I've used on on my 55-200 vr lens without issue, but have been doing some reading that the 7-300mm is picky. What would be a good filter for this lens that would not distort image quality?

Test the lens without the filter.
What is being said about the lens being picky about the filter?
 

aaronw1986

macrumors 68030
Original poster
Oct 31, 2006
2,622
10
Test the lens without the filter.
What is being said about the lens being picky about the filter?

I did test without the filter. The results seemed better. Though it still seemed like the 55-200 outperforms it in terms of IQ.
 
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