This dimension that dimension

[Izzy]

No this is not about parallel universes. This is about my T2i occasionally cranking out pictures that are about 5-8 pixels off from being the true dimensions. This is only obvious when I go to 500x750 for web posting and 16x24 for larger format prints as I end up with goofy numbers.

This is never a problem as I just unlock constrain proportions in PS CS3 and then set them for the exact dimension that I need. It has minimal effect on the picture overall.

Normally my pictures are imported to Lightroom 3 and then managed from there. The only time I use PS is if I am making a black and white of resizing for printing.

is this anomaly normal?

[ravncat]

absolutely normal, has alot to do with pixels on the cmos sensor being used for other things - and there`s often edge masking for dark subtractions and all sorts of stuff that goes on - and tolerance factors - i think, for example, the d70 is 3008x2000 pixels, which is a bit off of 3:2 - as far as I know, all cameras are close to these aspect ratio`s but few to none are spot on...

i wouldnt worry about it

[Izzy]

What is strange is sometimes it is right on - I mean in aspect ratio and sometimes off a few pixels??

[OsmosisStudios]

Is this any JPG from the camera, or from an exported RAW?
Does it happen only in certain shooting modes or certain speciality modes (long exposure noise reduction, bracketing of some kind, etc)?

[ravncat]

Originally Posted by Izzy

What is strange is sometimes it is right on - I mean in aspect ratio and sometimes off a few pixels??

Hrm - check to see if there are any settings that are constant that could be making a difference - jpg vs raw, jpg size/compression, iso setting, etc... could be position of the sensor from dust reduction/vibration... im not sure

[Izzy]

So far that I can tell this is only when shooting in jpeg. I know I should be shooting RAW but .... I digress.

I guess I dont shoot RAW often enough to notice if it is doing it there. The only thing I shot RAW in the last month was my daughters graduation in low light which helped me rescue some of them.

Good question Os.

Because I am generally lazy photographically I usually have it in P mode. Unless I am looking for a specific effect like DOF or stop action it pretty much stays on P mode.

The goofy sizes seem to have no discernible pattern at this time

Maybe I will try RAW for a few weeks and see if I get the same goofy image sizes. This could have something to do with in camera jpeg compression?

[Izzy]

Follow up

I did figure out where this dimension change happens. It is in LR3 when I crop and rotate. Like I said it was just a few pixels but it was there.