500px, Color Profiles, File Formats and You – 500px ISO

“Color profile support has long been a tough technical challenge – and doubly so, it would seem, in the world (wide web) of browsers. There have been several advances that have made the team at 500px re-evaluate how we handle color profiles on the site.

In the past, to be the most consistent, the most widely supported, and the most space efficient, we did two things:

1. Convert any image not using an sRGB color profile to sRGB
2. Strip the color profile from the image

Why did we do these things?

The first step is fairly obvious. Until recently, most screens were sRGB calibrated, or weren’t calibrated, but were close enough to sRGB for most purposes. This meant people with wide gamut displays wouldn’t get to see the images uploaded in wide gamut profiles (Adobe RGB, ProPhoto RGB, Display-P3, etc) in their full glory, but it also meant the most people would see something close to what the photographer intended.

The second step is a little more subtle. The default sRGB color profile is about 3KB when attached to an image (we’ve also seen non-standard profiles take 20KB). For a 5KB thumbnail, that needlessly increases the file size by more than 50%. The W3C consortium states that an image without a color profile should be assumed to be sRGB, so all should be good when an sRGB image is stripped of its profile. Stripping the color profile from the image turned out to be a pretty big deal, as it saved 25-30% in data transferred, which translated into tens of thousands of dollars in bandwidth savings per month and – most importantly – drastically sped up image downloads (especially the thumbnails). Life was good… but as we know, it’s rarely easy.”

Fascinating stuff about color profiles and how they are supported (or not) in different browsers and on different platforms. I knew this stuff was confusing, but this article does make a lot of it more understandable.

FYI, I use 500px to display my photos.

Source: 500px ISO » Beautiful Photography, Incredible Stories…500px, Color Profiles, File Formats and You – 500px ISO

Tips for Using Auto and Manual Focus on the Fujifilm X100F Camera

(This article is a follow-up to one I wrote yesterday about my other camera, the Olympus Pen-F, where I explained how to get precise focus using both auto and manual focusing.)

Auto-focus on modern cameras is great. It is often very precise, and makes it a lot easier to shoot photos quickly. However, it’s not always perfect, especially if you’re trying to focus on something with a lot of different elements that are at slightly different distances. If you’re using a wide aperture, with less depth of field, it’s possible that part of your shot may be out of focus. You may even see this on portraits, where part of a face may be sharp, and other parts soft.

Most good modern cameras also offer a manual focus option. You won’t find this on a point-and-shoot camera, but any camera with interchangeable lenses, and some without, give you the possibility to focus manually. One of my two cameras is the Fujifilm X100F, which offers manual focus, and has some “Focus Assist” features which are really useful.

First, you want to set the camera to use both auto and manual focus. Go to the AF MF Menu and turn AF+MF On. This means that the camera will use auto-focus when you press the shutter halfway. But if you want, you can also use the focus ring on your lens to adjust focus; just start turning it while you’re holding down the shutter. When everything is ready, press the shutter the rest of the way to shoot a picture. (Note that on this camera you also have to set the switch on the left side of the body to S to have it perform single auto-focus.)

Fuji1

What’s really useful with this camera, however, is the fact that you can press the rear dial to zoom in on your subject, making it easier to see if you’re precisely in focus. This looks like a 10x zoom, and, as you’ll see, gives you a very good close-up allowing you to make sure that your subject is sharp.

Fuji2

And if you move the wheel to either side, it switches to what looks like a 5x zoom, which, for some subjects, is a lot more helpful. (I don’t shoot portraits, but I can imagine that zooming to 5x would make it easier to ensure that an entire face is in focus.)

Fuji3

Another option in the MF Assist menu – just below the AF+MF menu – lets you use Standard assistance or Focus Peak Highlight. This second option displays white lines that highlight the areas in focus. You can adjust the color and intensity of these lines in the Focus Peake Highlight sub-menu. In that menu is also a third option, Digital Split Image, which is only available when you’re in full manual mode (the side switch set to M). This recalls old film cameras, where you had a circle in the center of the viewfinder that was darker, and you aligned the two halves of the circle to ensure that your subject was in focus. I used to like those circles, but I find the split image here – which is a pair of rectangles – is hard to use. But you can zoom in the same way as above using the rear dial, so you can get good focus with this tool as well.

So learn how to use these tools to get all your photos in perfect focus.

Tips for Using Auto and Manual Focus on the Olympus Pen-F Camera

(I’ve also written another article about auto and manual focus in my other camera, the Fujifilm X100F.)

Auto-focus on modern cameras is great. It is often very precise, and makes it a lot easier to shoot photos quickly. However, it’s not always perfect, especially if you’re trying to focus on something with a lot of different elements that are at slightly different distances. If you’re using a wide aperture, with less depth of field, it’s possible that part of your shot may be out of focus. You may even see this on portraits, where part of a face may be sharp, and other parts soft.

Most good modern cameras also offer a manual focus option. You won’t find this on a point-and-shoot camera, but any camera with interchangeable lenses, and some without, give you the possibility to focus manually. One of my two cameras is the Olympus Pen-F, which offers manual focus, and has some “Focus Assist” features which are really useful.

First, you want to set the camera to use both auto and manual focus. Go to the Custom Menu > AF/MF > AF Mode > Still Picture, and select S-AF+MF. This means that the camera will use single auto-focus when you press the shutter halfway. But if you want, you can also use the focus ring on your lens to adjust focus; just start turning it while you’re holding down the shutter. When everything is ready, press the shutter the rest of the way to shoot a picture.

What’s really useful with this camera, however, is the MF Assist settings (at Custom Menu > AF/MF). You have two options: Magnify and Peaking. If you select Magnify, the viewfinder or back LCD zooms in on your focus point, making it easier to see if you’re precisely in focus. This is a 10x zoom, and, as you’ll see, gives you a very good close-up allowing you to make sure that your subject is sharp.

The second option, Peaking, displays white lines that highlight the areas in focus. You can adjust the color and intensity of these lines in Custom Menu > Disp/PC > Peaking. You can change the intensity and color of these lines.

Here’s a shot of the Pen-F focusing on a pen holder a few feet away:

Focus1

When I start moving the focus ring in the lens, here’s how it looks at 10x zoom:

Focus

Remember, the camera zooms in on your focus point, so if it’s not centered, you won’t see the zoom at the center of the image.

I find that the Magnify setting is much more useful than Peaking. I don’t like the intrusive lines, though they may be useful for certain types of photos (such as macro photography). But with the Magnify feature turned on, I can make sure that I’m always in focus.

You can also use this in pure manual focus mode. As soon as you start moving the focus ring on your lens, the camera zooms in. I find this a bit more distracting, since it’s harder to compose images, but if you’re shooting on a tripod, this is a lot easier to use, since you’ll first compose your image in the LCD, then focus; you won’t need to worry about holding down the shutter half way then shooting.