Sony's response to the XS-1 ?

Started Oct 12, 2013 | Discussions thread
photoreddi Veteran Member • Posts: 7,812
Re: Sony's response to the XS-1 ?

jcmarfilph wrote:

photoreddi wrote:

jcmarfilph wrote:

SHood wrote:

At $1300 it will be double the price of the XS-1 and the zoom only goes to 200mm. But it will have a 1" sensor and likely a much larger EVF. This looks more like a replacement for the F828 from almost 10 years ago. It'll be interesting to see how it sells, but either way you have to give kudos to Sony for taking a risk.

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Now it must have at least 20MP resolution to match (thru cropping) the focal length of standard bridge cam. And hopefully a nice 2x TC will go along with it.

No, cropping a 20mp image could never be good enough to match the focal length of a bridge camera. To match the field of view of an X-S1 you'd get a 2.0mp cropped image.

Your calculation is exaggerated. The actual FL of X-S1 is 158mm and RX10 has 75mm. Crop the RX10 to 50% and it will give you 5MP. Still lower but not 2MP and it is close to EXR mode of X-S1.

Your method is flawed. It doesn't account for the different sensor sizes or sensor crop factors. To match the X-S1's "reach" (624mm) you'd have to crop away most of the RX10's image so that what remained was the same as what the X-S1 filled the frame with. If you do a 50% linear crop, you do end up with the 5mp image that you calculated, but it's not equivalent to what a 624mm lens would produce on a full frame DSLR, it's only equivalent to what a 400mm lens would produce. Dragging EXR mode into the discussion is just hand waving, doing little other than to distract from the discussion. I'm not aware of any EXR mode that affects the focal length, although one of the EXR modes cuts the resolution in half, but that doesn't help the RX10 to match the X-S1's focal length.


To match the field of view of an HS50EXR you'd end up with an 0.8mp crop. It looks like you're dividing the Sony's 20mp sensor by the ratio of the focal lengths. Megapixels of two camera's images are compared by the areas of the portion of the sensor that's used, not by the linear size of the sensor's edges. So for the 1,000mm HS50EXR, you'd divide 20mp by ((1000/200)*(1000/200)) to get the number of pixels in the cropped portion of the 20mp sensor. Put another way, the divisor equals 25, so to get a 10mp crop out of the Sony's sensor having the same FOV as the HS50EXR, the Sony would have to have a 250mp sensor.

HS50 has 185mm FL so do your math.

I did. Your math (method) is still flawed. Again, you can't use actual focal lengths to make comparisons unless the sensor sizes are the same. Using your math a 185mm lens would have the same field of view whether it's on a P&S with a tiny 1/2.3" sensor, an HS50EXR or a full frame DSLR.


And you can upsize the RX10 shot so you will end up with enough resolution for printing.

Whether it's a 2mp crop of the RX10's image that duplicates the FOV of the 624mm X-S1 or a 0.8mp crop that duplicates the FOV of the HS50's 1,000mm, you would only have enough detail to make  small high quality prints. 2mp is 2mp, no matter which camera produces it. That's enough to make a decent 5"x7" print that isn't quite tack sharp. A 0.8mp image that duplicates the FOV of the HS50 at 1,000mm would be even less sharp if it was used only for 4"x6" prints. Upsizing doesn't add more detail unless you're talking about the false detail added by programs like Genuine Fractals, otherwise at best it just smooths away the stair-stepping that uncorrected upsizing would create.

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