image quality wise, which one should i go with?
lens I have. EFS-60, EF 50 1.4, 17-85, 70-400 F4 IS
image quality wise, which one should i go with?
lens I have. EFS-60, EF 50 1.4, 17-85, 70-400 F4 IS
In some cases they will be very close, but there are many cases where the 5D will have superior image quality. The biggest difference is that the 5D will give you more light gathering power and thinner DOF for any given field of view and f-number. It will also give slightly better dynamic range, though not very much due to the low read noise in the XSi.
Generally, the MTF (contrast for a given resolution) of a lens goes
down as spatial frequency goes up. Since 12 MP on APS-C is a higher
frequency than 12 MP on FF35, the 5D gets the benefit of the higher MTF
(contrast) at any given print size. However, EF-S lenses don't need to
cover the same image area, so they are designed for the same MTF at
higher spatial frequencies. The 17-55 f/2.8 and 60mm macro are good examples of this.
It also depends on the lens. For example, for macro shooting, I don't think you'll get much better resolution or contrast from 5D+100mm f/2.8 macro than you would get from XSi and EF-S 60mm.
The 28-135 on the 5D is similar to the 17-85 on the XSi, but I don't know if the contrast/resolution would be better or not. The 24-105 certainly would be better.
The 70-200 f/4 L IS will give higher contrast on FF35 for any given field of view, but I don't think you will notice a difference in resolution.
I hope that helps.
It might be relevant to your decision that the EF-S 60mm Macro andthe EF-S 17-85mm lenses simply won't work on a 5D.
For the EF 50 f/1.4 and the 70-(200?) f/4 IS, I'd take the 5D hands down.
by thinner dof , do you mean the area in focus will seem smaller? I guess that makes sense. that's the problem I do either a lot of macro or telephoto, rarely wide angle.
17-85 I'm not worried so much since I'm ready to sell it any day, 60mm macro i'm kind of bummed that I couldn't use it it's what I felt the best bang for the buck lens in my purchase, followed by the 50...
and yes, I purchased the 50 and 70-200 because I know I want to go full frame one day, just don't know when yet.
I do have a question that I keep scratching my head over with, many people said that you get more "reach" with 70-200 on cropped lens, when I think about it, I'd imagine that's "perceivedreach" since your imagesensordoes the cropping for you... I mean I'd like to make the decision or rather have theabilitycrop on my own if I do want that "extra perceived reach" on the final print out. am I missing something?
ultima - I mostly use my XTi for telephoto and macro shots. If I had a FF sensor, and cropped to achieve the 1.6x effect,I would have spent alot more money to not use it. Of course FF allows you to take full advantage of the wide angle end of the spectrum, if that's what you need.
Daniel-I'm going to have to disagree with you on the FF having a thinner DOP. The distance between the lens and sensor is the same on FF and Cropped Frame cameras. The DOP may look deeper on the cropped frame, because it appears closer. Here's an example:
http://www.have-camera-will-travel.com/field_reports/full_frame_vs_crop_sensor_-.html
Originally Posted by Steve Eisenberg
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If you try to achieve the same crop you'd get from 1.6 with FF, you will certainly have a different DOP. If I use a 50mm lens on a 1.6, then I'm going to use an 85mm (or even a zoom at 80mm to make it exact) to get similar crop on the FF, then background is definitely going to be more blurred.
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That guy is definitely not going for similar crops and clearly doesn't understand what people are talking about when the talk about FF having better depth of field. I guess that is why people are so sensitive about information given on these boards. There is a lot of bad info being supplied by anyone who has ten extra minutes to blog about stuff they think they know about.
If you use a diifferent focal length, of course you have a different depth of field. But you can also achieve the same crop by literally cropping the image.
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If you try to achieve the same crop you'd get from 1.6 with FF, you will certainly have a different DOP. If I use a 50mm lens on a 1.6, then I'm going to use an 85mm (or even a zoom at 80mm to make it exact) to get similar crop on the FF, then background is definitely going to be more blurred.
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That guy is definitely not going for similar crops and clearly doesn't understand what people are talking about when the talk about FF having better depth of field. I guess that is why people are so sensitive about information given on these boards. There is a lot of bad info being supplied by anyone who has ten extra minutes to blog about stuff they think they know about.
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Yes. If we set aside bellows factor, resolution, and post-processing differences, the only factor that affects the DOF is the lens (or, you could think of it as "lens, sensor size, and print size", but I prefer to think of it as just the lens).
It's important to remember that aperture is not the same as f-number. Aperture is the focal length divided by f-number, so that a 100mm f/4 lens has an aperture of 25mm (100/4).
There are several ways this principle can be stated:
- The lens with the widest aperture has the thinnest DOF, no matter what camera or focal length.
- When aperture is the same, the lenses have the same DOF, no matter what camera or focal length.
- When f-number *and* composition are the same, DOF gets thinner with larger sensors.
What I mean by "composition" is: field of view, perspective, and focus distance.
It's possible to compare two different cameras (e.g. 5D and XSi) using two different compositions. For example, if you put a tripod in a certain spot and don't move it, then put the 50mm f/1.4 on the XSi, set it to f/1.4, and have a focus distance of 5 meters, then you have a certain 25-degree horizontal angle of view. If you do the exact same thing with the 5D, then everything is the same except for the angle of view (field of view), which will be 45 degrees instead of 25.
The DOF will be the same, but the angle of view will be different. I don't think it makes sense to compare different angles of view, because that's a fundamental component of the photographer's composition, and he isn't going to start shooting wider just because he upgraded to full frame: instead, he's going to find a new lens that will give him the same capability that 50mm did on his XSi: such as the 85mm f/1.8.
100mm f/4 on the XSi has the same DOF as 160mm f/6.4 on the 5D. Both have the same composition and both have an aperture of 25mm.
160mm f/4 on the 5D has the same composition as 100mm f/4 on the XSi, but it has thinner DOF. Another way to look at it is this: the 5D will give all your full frame lenses a wider field of view and thinner DOF, unless you stop down to the same aperture for a given composition.
By the way, DOF isn't the only factor that scales with aperture. Light gathering power and diffraction do too.
The "reach" is real. The way it works is like this: if you crop a 5D to the same size as 1.6X, you're left with much fewer pixels on the subject than if you had just shot a 1.6X camera in the first place. Here's another way to look at it:
If you bought the $2,700 5D2, shot it at 200mm, then cropped it to 1.6X, you would have an 8 MP image.
if you bought a used $300 20D, shot it at 200mm from the same distance as above, you will get the exact same image (and 8 MP to boot).
In other words: it does you no good to pay all that extra money for "full frame" unless you're going to use the "full frame" in your images. Wildlife photography and macrophotography often benefit from the crop factor for that reason.
To answer the OP, I would think it would be germane to know the price range of the used 5D he's seen. I would think that it would be significantly more than a new XSi. Aren't they only $700-800?
A more apples-to-apples might be a used 5D vs a new 50D. In that case, I would suggest the 50D, as I've seen them for $1200-1300, which is roughlyequivalent toa good used 5D.
Also, as has been pointed out, all the OP's current lenses will work, whereas the FF body could only work with two of them, although those two are very nice.
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