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Wingnut330
14th of April 2008 (Mon), 11:08
I'd like to search on this technique, but I have no idea what it's called. :oops:

It's when you have something in focus (person, animal etc) but the background is fuzzy. Not blurry like an action shot, just fuzzy so the person in the shot is more noticeable.

I'm curious what it's called and how I do it. Thanks in advance.

Skrim17
14th of April 2008 (Mon), 11:09
It is called bokeh. If you use a lens at a large aperture, the background gets blurry, also having the background not too close to the item in focus helps as well.

Wingnut330
14th of April 2008 (Mon), 11:12
Cool - thanks! I'll try searching on here and see what I can turn up. I'd like to take some shots like that of my son, but have no clue how to do it.

Jon
14th of April 2008 (Mon), 11:14
Actually, it's called a shallow depth of field. But using large apertures and maximizing the separation between your subject and the foreground/background is the way to achieve it. Bokeh is the quality of that blur, and is heavily dependent on the particular lens.

Mike
14th of April 2008 (Mon), 11:46
Yeah, what Jon said! :D

You want to set your lens to it's widest aperture (lowest f-stop number) for the shallowest depth of field. If you have just the kit lens this will be f5.6 at 55mm, use Av mode for starters to try different apertures. Maybe have a look at the canon 50mm f1.8 lens (often referred to as the "nifty fifty") which is a good, cheap start (around 70) in shallow depth of field range of lenses.

You can also add a selective blur with software like photoshop but that's quite a bit more of an in-depth "how to" and more suited to the image processing section of the forum.

Dermit
14th of April 2008 (Mon), 12:25
The larger the aperture (smaller numbers) the shallower the DOF. The longer the focal length of the lens and the closer to the subject the shallower the DOF. So if you had a 200mm at f/2.8 and you were only 10 feet from the subject your DOF would be about 1 inch. Everything in front of and behind that one inch area of focus would be blurry.

Wingnut330
14th of April 2008 (Mon), 13:27
Yeah, what Jon said! :D

You want to set your lens to it's widest aperture (lowest f-stop number) for the shallowest depth of field. If you have just the kit lens this will be f5.6 at 55mm, use Av mode for starters to try different apertures. Maybe have a look at the canon 50mm f1.8 lens (often referred to as the "nifty fifty") which is a good, cheap start (around 70) in shallow depth of field range of lenses.

You can also add a selective blur with software like photoshop but that's quite a bit more of an in-depth "how to" and more suited to the image processing section of the forum.

I bought the 50mm f1.4 at lunch today. I can't wait to tinker with it later tonight. I'll give your suggestions a try and see how it goes. It should be interesting cause I have no idea what I'm doing! :D

Chet
14th of April 2008 (Mon), 13:45
I bought the 50mm f1.4 at lunch today. I can't wait to tinker with it later tonight. I'll give your suggestions a try and see how it goes. It should be interesting cause I have no idea what I'm doing! :D


So you'll want to shoot at F1.4 area for a shallow depth of field as said above. Use aperture priority or manual to achieve.

You picked a great lens for detail shots, good luck and post some results.

Mike
14th of April 2008 (Mon), 14:14
I bought the 50mm f1.4 at lunch today. I can't wait to tinker with it later tonight. I'll give your suggestions a try and see how it goes. It should be interesting cause I have no idea what I'm doing! :D

Nice, even better than the nifty!

I recently got a 30mm f1.4 - it's great for shallow dof.

Remember though that because the dof is so shallow, any movement between focusing and firing the shutter may cause the focus to miss. Not always, but it's possible.

The other added bonus with an aperture of f1.4 is that you have more scope to shoot handheld in low light situations.

I look forward to seeing your results... :)

Wingnut330
14th of April 2008 (Mon), 14:28
OK - so I turn on the camera, switch it to Av, make sure it's at 1.4 and fire away correct?

Chet
14th of April 2008 (Mon), 14:32
OK - so I turn on the camera, switch it to Av, make sure it's at 1.4 and fire away correct?



Yes that will be a great starting point to try it out. Then you can start raising it to 2.8 then 5.6 and you will start to see more of your background coming into focus.

Mike
14th of April 2008 (Mon), 14:35
OK - so I turn on the camera, switch it to Av, make sure it's at 1.4 and fire away correct?

Yup. Don't forget to use just a single focus point too otherwise your focus will be all over the place.

Wingnut330
14th of April 2008 (Mon), 15:17
Yup. Don't forget to use just a single focus point too otherwise your focus will be all over the place.

I see that I have 9 focus points. Thus far, I have just been shooting things in the center for now. I'm assuming there is a way to pick which of the 9 I want to to use and that you are suggesting learning how to make that choice correct?

Mike
14th of April 2008 (Mon), 15:41
Yeah. If you shoot on the centre point, that's fine as it is believed to be the best - most sensitive af point. That, however, can be a bit dull compositionally sometimes and with an aperture at f1.4 you can't do the focus & re-compose trick so easily, so once you're comfortable at hitting focus with the centre point try using a different focus point for more interesting composition.
You should have an af-point selector button (I'm not too farmiliar with the Rebel series) that, once pressed, will enable you to select your focus point.

yogestee
14th of April 2008 (Mon), 21:40
I'd like to search on this technique, but I have no idea what it's called. :oops:

It's when you have something in focus (person, animal etc) but the background is fuzzy. Not blurry like an action shot, just fuzzy so the person in the shot is more noticeable.

I'm curious what it's called and how I do it. Thanks in advance.

The term is call "selective focusing"..Works best with wide apertures and/or long lenses when the depth of field is shallow..

The pattern of the out of focus back ground is call the "bokeh"..

Mike
15th of April 2008 (Tue), 16:12
How's you get on? Need pics...! :)

Wingnut330
15th of April 2008 (Tue), 17:42
Happy to! How do I post them?

Mike
15th of April 2008 (Tue), 17:56
Ah...See here: http://photography-on-the.net/forum/showthread.php?t=157528

Basically, resize your image to a maximum of 1024 pixels on the longest size and save it as a jpeg under 150 kb in size, click on the "Go Advanced" button below and then the "Manage Attachments" button that you will see. Browse to your newly resized photo and attach it. Click "Upload" and bob's your uncle!

Wingnut330
15th of April 2008 (Tue), 20:13
OK here goes. The first 2 are a couple of tests that I did. First I tried focusing on the basket - easy with autofocus. The stools in the background were blurry. Then I tried to focus on the stool and make the basket blurry. I was able to, but had to use manual focus...

Wingnut330
15th of April 2008 (Tue), 20:15
Here are some other random shots I took while tinkering with the new lens. They are of my neighbors cat that I regularly feed. :D

Wingnut330
15th of April 2008 (Tue), 20:19
A couple more...

Wingnut330
15th of April 2008 (Tue), 20:20
Last but not least - my son. Nice tooth eh?

JeffreyG
15th of April 2008 (Tue), 21:02
Las tbut not least - my son. Nice tooth eh?


You are getting it. Here is one critique on that last shot. It looks to me that you used the center focus point and focussed on that one tooth or the nose. Unfortunately, this means the eyes are slightly soft.

When you shoot portraits with a very shallow DOF, there are two things two keep in mind:
1. With fast primes at least, the field of acceptable sharpness can be really thin - like 10mm and so focus is absolutely critical.
2. The eyes absolutely must be in that critical field of focus or it will be obvious.

Viewers will tolerate soft ears, noses, lips and hair but if the eyes are soft the shot is not a keeper.

Also feel free to stop down a little. f/2 is still plenty fast, the lens will be a little sharper and the DOF will be a little bit more forgiving.

Wingnut330
15th of April 2008 (Tue), 21:41
You are getting it. Here is one critique on that last shot. It looks to me that you used the center focus point and focussed on that one tooth or the nose. Unfortunately, this means the eyes are slightly soft.

When you shoot portraits with a very shallow DOF, there are two things two keep in mind:
1. With fast primes at least, the field of acceptable sharpness can be really thin - like 10mm and so focus is absolutely critical.
2. The eyes absolutely must be in that critical field of focus or it will be obvious.

Viewers will tolerate soft ears, noses, lips and hair but if the eyes are soft the shot is not a keeper.

Also feel free to stop down a little. f/2 is still plenty fast, the lens will be a little sharper and the DOF will be a little bit more forgiving.

Thanks for the tips. I thought the exact same thing - that his eyes seemed soft. My problem at the time was that (as most kids do) he was squirming all over the place. I did exactly what you said, I autofocused on the center of his face (nose) and hoped for the best. I like the idea of focusing on the eyes next time. I will give that a try.

Mike
16th of April 2008 (Wed), 03:11
Nice set, I like the 2nd cat pic. Good start and as JeffreyG said, you need to work on your focusing - "the eyes have it!"