Resize before or after

[EchoingWhisper]

Do you think it is better to choose a smaller size when taking pictures or reduce the size using Bicubic Sharper in PS CS5?

If I already know that I don't need such a big picture, which one should I choose? Is the quality of picture resized smaller in PS better or is the original made-in-camera picture better?

 

[The_Traveler]

Resize on PS, keep the larger one with more details.
The only time I would think of shooting a smaller size was if I was taking a great many shots for a specific need and wanted to do as little work as possible.

 

[KmH]

Capture as many pixels as your camera can deliver, because the pixel dimensions are the image resolution.

Never edit the original.

 

[480sparky38 37]

If all I am ever going to do with the image is to email or post it on a forum, I'll shoot at the smallest size the camera is capable of. Otherwise, I shoot flat-out big.

 

[Garbz]

If I already know that I don't need such a big picture

Expand on this comment please. It sounds like you're trying to say "If I already know that I don't need an image of good quality or any effort or work put into its making", which is quite a legitimate statement and one that I use quite frequently.

When discussing engineering toys with mates I quite frequently use the same principle. The person needs to see the thing, not the photograph. In cases where quality is of no consequence other than to add extra effort to the basic task you're trying to do, forgo it. When I need to send a picture of something quickly I'll drop my camera in to small mode which saves the hassle of resizing on the computer, or having to deal with the possibility of someone rejecting a 5mb email etc.

If you need any kind of quality always shoot big and adjust.

 

[analog.universe]

In a situation of least effort, I have a quick shortcut, where I can right-click a jpg in my image browser and quickly resize it. This takes less time than changing the size in camera and then changing it back (provided you remember to change it back). I'm always leery of any suggestion to throw out data unless absolutely necessary. It makes the most sense to me to capture as much you can, save it somewhere safe, and then mess about however you wanna mess about. The actual quality difference between the resampler in PS and the Camera is likely to be negligible. However, if you want to do any kind of noise reduction, or sharpening, or pretty much any kind of pixel manipulation (as opposed to level manipulation), you'll get a better result resizing at the end. With extremely few exceptions, my flow goes: shoot largest RAW > convert to full resolution TIFF > do stuff, or not > resize > sharpen > save as JPG. For images where I don't care about the quality, it takes like 3 clicks to do RAW to TIFF using some default, and then from TIFF to resized JPG using some default.

 

[EchoingWhisper]

Example: If I know I am going to need 6 inch x 6 inch on print, I will only need 4 megapixels at most. Should I take pictures at 4 megapixels or more?

I want to know how the camera works. Does the camera resize the image after it have taken it or does it use only some of the pixels on the sensor?

 

[analog.universe]

I would always use the full resolution the camera provides... the only reason not to would be burst rate or storage space. If you're not limited by either of those factors, get as many pixels as you can. The more you have to work with, the easier it will be to do good post-production. If you have large originals stashed somewhere unedited, then you're not locked into your 6x6 print. What if years down the road you decide to print something at 12x12? Unless you're really constrained by the time and space required to capture larger images, shooting reduced resolution creates unnecessary limits on future work.

 

[edddial]

Take highest resolution, you may want to crop it. Eventually you may want to print on larger paper or put on wall paper (high resolution monitor). Then you need high capacity SD card/CF card.

 

[KmH]

Example: If I know I am going to need 6 inch x 6 inch on print, I will only need 4 megapixels at most. Should I take pictures at 4 megapixels or more?

I want to know how the camera works. Does the camera resize the image after it have taken it or does it use only some of the pixels on the sensor?

First you will have to crop some of those 4 MP away to make a 1:1 aspect ratio print (6x6). You don't say what camera is involved, but most DSLRs give 3:2 aspect ratio photos, while a few give a 4:3 aspect ratio image.

Second, a 6x6 print is a gift or desk size print, and will be looked at from a small distance, usually less than arm length. So, it will need to be printed using a fair number of pixels per inch (PPI).

If the 6x6 print is made using 300 PPI, the math indicates we need - 300 PPI x 6 inches = 1800 pixels on each side of the print. Again thinking of the native aspect ratio of the camera, we may need as many as 2700 pixels by 1800 pixels in the original image if the camera has a native 3:2 aspect ratio.

If you are willing to forgo some image quality by printed a 6x6 at a smaller PPI, the math indicates - 200 PPI x 6 inches = 1200 pixels and 100 PPI x 6 inches = 600 pixels.

As far as how the camera works when making reduced resolution photos: Which Camera?

But, the size of the pixels on the image sensor cannot be changed.

The Nikon D7000 shows the following pixel dimensions for the 3 image sizes it has available.

DX-format
(L) 4928 x 3264
(M) 3696 x 2448
(S) 2464 x 1632

 

[EchoingWhisper]

Example: If I know I am going to need 6 inch x 6 inch on print, I will only need 4 megapixels at most. Should I take pictures at 4 megapixels or more?

I want to know how the camera works. Does the camera resize the image after it have taken it or does it use only some of the pixels on the sensor?

First you will have to crop some of those 4 MP away to make a 1:1 aspect ratio print (6x6). You don't say what camera is involved, but most DSLRs give 3:2 aspect ratio photos, while a few give a 4:3 aspect ratio image.

Second, a 6x6 print is a gift or desk size print, and will be looked at from a small distance, usually less than arm length. So, it will need to be printed using a fair number of pixels per inch (PPI).

If the 6x6 print is made using 300 PPI, the math indicates we need - 300 PPI x 6 inches = 1800 pixels on each side of the print. Again thinking of the native aspect ratio of the camera, we may need as many as 2700 pixels by 1800 pixels in the original image if the camera has a native 3:2 aspect ratio.

If you are willing to forgo some image quality by printed a 6x6 at a smaller PPI, the math indicates - 200 PPI x 6 inches = 1200 pixels and 100 PPI x 6 inches = 600 pixels.

As far as how the camera works when making reduced resolution photos: Which Camera?

But, the size of the pixels on the image sensor cannot be changed.

The Nikon D7000 shows the following pixel dimensions for the 3 image sizes it has available.

DX-format
(L) 4928 x 3264
(M) 3696 x 2448
(S) 2464 x 1632

Just an example. I just want to know if the camera use less of its sensor or it has some kind of algorithm to reduce the image size.

 

[KmH]

You'll have to query the company that made your camera.