Making a big image smaller WITHOUT resizing it

[slipshot180]

Hey everyone, this is my first post! i have been coming to this forum alot to view tip and tricks but i finally buckled down and registered! I got into DSLR photography about 6 months ago, i understand the majority of the elements that come into play into taking amazing photographs but i would still call myself a beginner.

Soooo i recently got into product photography and i have come across what seems like a huge stumbling block, i was wondering if you guys could help!

I learned that shooting raw is always the way to go-but when ever i downsample (resize a image to a smaller size) it tends to lose its sharpness and image quality. I use a D7000 which shoots at 4000+px by 2000+px. I shoot portrait style(pics are tall) and i need the images to be around 600*300 for my website. The thing i dont seem to understand is when im in photoshop and i zoom out of the image to say 15%, its the perfect size and the picture doesnt lose quality. The same thing happens when i open the picture on a mac in preview mode (spacebar).

so my question is is there a way to make pictures smaller and retain the image quality and size without resizing it?

I can shoot in jpeg, small but i love having the extra editing features that raw has. I checked the Raw option there is no way to change image size.

 

[Ysarex]

so my question is is there a way to make pictures smaller and retain the image quality and size without resizing it?

If you need your finished photo to be 600 x 300 pixels then you have to make it 600 x 300 pixels. If it's bigger than 600 x 300 pixels then it isn't 600 x 300 pixels. This one is just that simple.

How you resize it however matters. If you're in Photoshop and using the Image Size dialog you'll see a drop box at the bottom of the dialog. There you'll find a list of different resizing algorithms. Pick the right one. If you don't know which one is the right one then start running tests.

Once you resize your photo you'll need to sharpen it. Don't sharpen it first and then resize it. Resize it first and then sharpen it. Learn to use the Smart Sharpen option in Photoshop: Filters/Sharpen/Smart Sharpen.

Joe

 

[Judobreaker]

Yep, you need to learn how to sharpen. ^^

 

[Tony S]

You really need to process the image for whatever the intended use is, there is no simple one step for everything resizing/sharpen that works. Depending on the image, I usually resize to the dimensions I need and do a final sharpen as my last step. For images that are sized for printing I will use USM with settings that vary for each image, for my internet sized images (800 pixels on the longest side) I will often go with a simple sharpen edges.

 

[KmH]

The algorithms Joe mentions are more accurately called resampling interpolation algorithms, but they are used when re-sizing an image.
Resampling is a process that compares adjacent pixlels and makes new ones. In the case of making images smaller adjacent pixels have to compared and combined into fewer new pixels which reduces detail.
To go from 4000 pixels to 600 pixels 6.67 original pixels have to be combined to make 1 new pixel.

Photoshop offers 5 algorithms for resampling interpolation.
Image editing texts usually recommend using the Bicubic Sharper algorithm when reducing image size.
If the result looks over sharpened, try Bicubic.

Understanding Digital Image Interpolation
Photoshop Elements Help | Resizing

 

[manaheim]

I'm sort of surprised OP is noticing any sharpness difference in making an image smaller, though... I mean 1. usually making an image smaller naturally sharpens it somewhat, no? And 2. I've been doing this for eons and never really noticed it... but then I don't usually pixel peep.

 

[rokstomper]

If all you want to do is save the picture a lot smaller memory wise say 1mb and still keep your 4000+pixels by 2000+pixels you can just go to save as and save it as a jpeg then slide the slide to whereever your desired amount of memory to take up is. Even number 0 has a decent amount of quality. If this is not what you wanted soorry to waste your time. Here is a screen shot of what I am talking about.
View attachment 45123

 

[KmH]

That only changes the FILE size, not the image size.

 

[rokstomper]

That only changes the FILE size, not the image size.

Correct me if I'm reading this wrong but the title says "Making a big image smaller WITHOUT resizing it". I interpret this as making it a smaller file size and not changing the anything to do with pixels. That is what the title leads me to believe. Makeing file sizes smaller is something I may be able to help with but I have never resized with the pixel count. I am just giving the knowledge of the subject I have to the op you never no it might just be helpful. I might not exactly understand the question.

 

[Overread]

When I resize for the net my process is as follows:

1) Perform all needed editing on the photo, leaving noise reduction and sharpening to the last step.

2) Perform noise reduction and sharpening as needed on the photo at fullsize.

3) Resize to around half the dimension it currently is (so if its 4000 on the longest side I resize to 2000 on the longest side) - after resizing I sharpen again (this helps restore lost sharpness after the resizing - even when using the algorithms for resizing which help limit the sharpness loss)

4) Resize again to half again and sharpen again (so taking the above example the 2000 pixel image is now taken to 1000 pixels on the longest side)

5) Resize and sharpen again if I need it any smaller (I typically stop at 1000 pixels, but if in your case you need to go smaller just repeat again).


Note that each stage will require different amounts of sharpening, typically you'll find the amount reducing as you go down. Be careful not to overshapen where you start to see odd edges or artifacts appearing. If you want more information on editing processes and methods I'd suggest checking out the following websites which have some great editing articles on stages:
Cambridge in Colour - Photography Tutorials & Learning Community
Ron Bigelow Photography Articles

 

[KmH]

That only changes the FILE size, not the image size.

Correct me if I'm reading this wrong but the title says "Making a big image smaller WITHOUT resizing it".

The OP wrote "​I use a D7000 which shoots at 4000+px by 2000+px. I shoot portrait style(pics are tall) and i need the images to be around 600*300 for my website.

You have to read the post, not just the title.

 

[rokstomper]

Yes I read that. I have no knowledge on that so I gave the knowledge I knew in hope of it helping the op or anybody else. I like overread's commint and it will help me personably in the future.