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8x and 10x (1 Viewer)
- Thread starter Rob T
- Start date
I may be wrong but I think a 400mm lens on an APS sensor would give 8x and a 500mm would be 10x.
WOW so you have to have a big lense?
Well it depends on sensor size and aperture, both of which affect IQ. Superzoom all in one cameras have small sensors and cheaper lighter DSLR lenses have small apertures.
For a big sensor you need a decent camera and for a big aperture you need a big lens.........
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As a rough guide in 35mm cameras ,and hence also full-frame DSLR's, a 50mm lens is perceived as being approximately 1x magnification. To get an indication of magnification for any lense just divide its focal length by 50, so 300mm = 6x etc.
Smaller sensors give higher apparent magnifications. Multiplying by the appropriate "crop factor" will adjust for smaller sensors, so for example 1.5x for an APS-C sensor. 300mm would now yield "9x".
The above is something of a simplification, but serves as a useful guide. HTH
Smaller sensors give higher apparent magnifications. Multiplying by the appropriate "crop factor" will adjust for smaller sensors, so for example 1.5x for an APS-C sensor. 300mm would now yield "9x".
The above is something of a simplification, but serves as a useful guide. HTH
Sandpiper
Mike Powell
I agree with Jumbo. On a full-frame DSLR to get the equivalent of 8x magnification you would need a 400mm lens, or a 500mm to get 10x. However, if you have a DSLR with a smaller sensor, such as APS-H, APS-C, or micro four-thirds then you do gain advantage by what is commonly known as the "crop factor".
The crop factor gives an apparent increase in focal length due to the smaller sensor size. In other words an APS-H sensor has a crop factor of 1.3x, APS-C 1.5/1.6x and micro four-thirds 2x. Therefore your 400mm lens would have the equivalent "reach" of 520mm with APS-H, 600/640mm with APS-C and 800mm with micro four-thirds.
Above all that, of course, you have the ability to "crop" your image during post processing on the computer. This allows you to remove any unwanted outer areas of the frame which will then result in a larger image of your subject, just like using an even bigger lens.
Hope all the above makes sense.
Mike
The crop factor gives an apparent increase in focal length due to the smaller sensor size. In other words an APS-H sensor has a crop factor of 1.3x, APS-C 1.5/1.6x and micro four-thirds 2x. Therefore your 400mm lens would have the equivalent "reach" of 520mm with APS-H, 600/640mm with APS-C and 800mm with micro four-thirds.
Above all that, of course, you have the ability to "crop" your image during post processing on the computer. This allows you to remove any unwanted outer areas of the frame which will then result in a larger image of your subject, just like using an even bigger lens.
Hope all the above makes sense.
Mike
mikenott
Flawed but improving!
I fully agree with the excellent advice above.
I just want to add that this is a good answer to know as I know that my 1DIV (1.3x) +1.4x extender + 300 f2.8 lens equates to 546mm which is 11x magnification and this is roughly the same as my 10x32 binos. So whatever I see through my binos is the size I will see with my camera.
Similarly, my 600 isii gives 600x1.3x1.6 which is 1092mm or 21x which is the bottom end of my Swaro scope.
It just helps manage expectations on quality of photos you can achieve.
Michael.
P.S. I am sure purists could quibble the maths/physics but it is near enough for me
I just want to add that this is a good answer to know as I know that my 1DIV (1.3x) +1.4x extender + 300 f2.8 lens equates to 546mm which is 11x magnification and this is roughly the same as my 10x32 binos. So whatever I see through my binos is the size I will see with my camera.
Similarly, my 600 isii gives 600x1.3x1.6 which is 1092mm or 21x which is the bottom end of my Swaro scope.
It just helps manage expectations on quality of photos you can achieve.
Michael.
P.S. I am sure purists could quibble the maths/physics but it is near enough for me
Some good explanations above. Another complication is that some cameras, e.g. micro 4/3 and superzooms, have a teleconverter setting that effectively doubles the magnification. So this means that with a micro 4/3 camera, for example, you would only need a 125 mm lens to get 10x binocular equivalent magnification (125 x 2x crop factor x 2x teleconverter setting). It also means you can get 1200 mm (24x) magnification with just a 300 mm lens. But the teleconverter setting does not work with RAW and requires you to select small picture size.
I do not know whether DSLRs have a similar teleconverter setting. (Note that I'm not talking about an actual physical teleconverter, but a setting within the camera).
Wow i have to learn about this. Does the Canon T series have this ?
I think that is what is called 'digital zoom' as opposed to 'optical zoom'. It is no different to cropping the photos on your PC.
I know the Canon 70D has this digital zoom for video, not sure if they have it for regular photos.
Is this the same as micro 4/3 or is this something else?
No it is not the same. Have been through this discussion many times, and have compared results myself. Try it and you'll see. I believe it is equivalent to increasing the crop factor of the camera by limiting the exposure to a portion of the sensor. But whatever the precise explanation, as Panasonic states in it's manuals, there is no deterioration in image quality from this setting--as opposed to what is usually referred to as digital zoom.
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I am sorry but i dont understand what you are doing or how? It sounds like you are on to something but I have to say i am not following? Help please
Jim is saying that on some cameras you can boost the magnification from within the settings menu. You should perhaps check the Panasonic/Olympus forums here (or on other sites) for more info on that.
So basically what everyone has said above can be summed up as follows:
On 'full frame' DSLR cameras a 400mm lens would give 8X. These cameras tend to be the most expensive (examples include the Canon 1D/5D, Nikon D4/D800) and have the highest image quality.
On so called 'crop' cameras the sensor is smaller giving an apparent boost in magnification (or 'reach'). The image quality generally isn't as good as full frame (especially at high ISO) but the cost/performance is good. Most consumer level DSLRs and mirrorless cameras are this type. The level of 'crop' varies from brand to brand. On Nikon it is 1.5 (so a 400mm lens would give 12X), Canon 1.6 (13X).
On Panasonic/Olympus (Micro 4/3) the crop factor is 2 (so a 300mm would give 12X). These are small cameras and they don't have the same choice of big heavy lenses as the types above.
On cameras which have non interchangeable lenses the sensors are generally much smaller (meaning a bigger 'crop') and magnification is often given as full frame equivalent, so you might see a 20X zoom with 20mm-400mm equivalent range (meaning 0.4X to 8X magnification). Image quality is not as high as the above 2 options. Some so called superzooms have very high magnification but suffer from high ISO noise and other problems which affect image quality.
Hope that helps, if I have said something which others think is wrong I'm sure I'll be corrected.
This is the general rule: the bigger and more expensive the gear is the better the picture will be. Many of us don't like paying the high premiums for this (or the physical cost of lugging it around) and end up compromising.
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Some recent Nikon DSLR bodies (e.g. D800) offer this option. By using only the center of the sensor to capture and not using the sensor periphery that makes for the size difference between the FF and DX sensors a FF body iis transformed to a DX (crop) body Obviously this costs pixels as only a fraction of the sensor is used, but one gets away with a smaller file and a slightly speedier camera. Same could be done in the computer at home by cropping off the periphery from the larger FF file. Still qualifies as digital zooming to me -in both cases.
Ulli
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WOW this would be great can I do this with m T1i? What do I do?
Paul - Herts
Paul Herts
Rob, if you are using a Canon DSLR there is no built in digital teleconverter
If you are using a Canon DSLR such as a 7D, 60D, 600D or 650D then the sensor's crop factor is 1.6x. A 300mm lens would give an equivalent of 420mm on such a body, or just over 8x magnification. A 400mm would give 640mm equivalent, or just under 13x magnification
Paul
If you are using a Canon DSLR such as a 7D, 60D, 600D or 650D then the sensor's crop factor is 1.6x. A 300mm lens would give an equivalent of 420mm on such a body, or just over 8x magnification. A 400mm would give 640mm equivalent, or just under 13x magnification
Paul
