File size....Megapixel count VS ACTUAL pixels gathered?
- Thread starter murphc13
- Start date
I assume those 23Mpix is the optical sharpness score? It doesn't mean your cam will shoot only 23MP with that lens.
Edit: make that perceptual instead of optical. Strike that too: optical sharpness, perceptual megapixels. The P- is most important in that label. MP is just a means to express it.
Looking for new photo gear? DxOMark's Perceptual Megapixel can help you! - DxOMark
Last edited:
I understand that in the case ofmy Tamron 24-70,it is getting 23 mp of the possible 36 from my d810(according to DXO).So are you guys saying that the "possible" max file size from a d810 could be the same as the possible max file size from a d3s?
And is it possible to get the same max file size using a d810 in combo with a 70-300 tamron vs a d810 and nikon 200 f2 combo?Or will the better optical quality of the 200 f2 produce bigger files than a lesser quality lens with the same body?
The maximum file size has little to do with the lens or cam but all with the format used and what is actually in the shot. A 36Mpix sensor usually has larger file-sizes but that's not because of the quality of a lens.
Take a shot of something and then take a shot with the lens cap on. Then compare file-sizes.
Horoscope Fish
Senior Member
Your understanding, simply put, is not correct.
Your D810 is capturing a 36MP image regardless of what lens you have on it; assuming you're not shooting in "DX Crop" mode.
The score of "23" from DxO Mark has nothing to do with image size.
.....
I'm sure the image with the lens cap on will be a smaller file.
I asked the original question assuming all settings equal....ie in Raw format.I should have mentioned that.
If the 3DS and the D810 would take the exact same RAW shot in FX mode, evidently the 36Mp cam would have a bigger file size than the 12Mp.
If a better performing lens can capture more of a sensors maximum theoretical image quality(MP) then would that extra image quality account for larger file sizes?Sorry for the noob questions but it would seem straight forward to me that if a better lens produces better quality images then better quality images will be bigger files.
Also do more megapixels equal more sharpness or more detail or both?
Also do more megapixels equal more sharpness or more detail or both?
Ok,so let's say two exact same shots in FX mode but with different lenses.....one that dxo says can muster 20 MP from a d810 and another lens that can muster 30 MP from a d810 then would the file sizes be the same?
There's a difference between the resolution of your shot and the pixels of a sensor. The more "sensor" pixels a cam has, the larger the resolution of the shot will be since the sensor pixels define that. But more does not necessarily translate into better quality or more detail.
Roughly the smaller the pixels of a sensor, the better it is for detail but a lot of factors define if or if not you can grab those details. On the other hand, the larger the sensor pixels, the more accurate the signal it captures but on its own that also means little.
Theoretically if you'd use two lenses on the same cam and would shoot the exact same shot, the better lens would result in a larger file size since it should be able to grab more data and thus has to write down more values in the RAW but in practice this is trivial.
The better the lens, the better the image quality and the DXO scores are about the perceived quality. But if my D750 + lens scores 19 and the D810 + same lens 23, it does not imply the shot of the D810 will be much better since it's 19/24 vs 23/36.
Thanks for this reply....but in your example...my setup will still yield 4 more megapixels....which translates into more detail.
Sure but it's not as if every value is written down separately and the RAW file contains 36 million entries for that.
I understand.The difference i actual "what you see" quality wouldn't be so great do you reckon?
The file sizes are not affected by the lens. The DxO score is a lens sharpness score. It tells the theoretical maximum resolution of the lens on the sensor.
Last edited:
For the DXO scores I think they consider all lower than "x" amount of difference in scores as neglectable since we won't see the difference. A score of 19 vs 20 as an example is irrelevant. But again, you have to compare scores of the same MP sensors.
In practice it means even less since we never take the exact same shot with two different lenses. Better lenses will perform better and result into better quality shots but you have to shoot them first and shoot them well.
The dxo scores are MP values....the theoretical maximum a particular lens can extract from a given sensor.So does more megapixels equal more sharpness or moe detail or both?
The higher the DxO score, the better the effective resolution. Basically, this will mean sharpness and detail, yes. Take a look at this link for more info:
Sharpness - DxOMark
Sharpness - DxOMark
Great!!!Thank you