Question about getting many things into focus at once.

[AKLforever]

Ok, I have the kit lens 18-55 and a 50 lens as well.
Now, something I notice is, no matter what I shoot, the target will be clear as day, but anything a lot closer or farther will be a bit blurry. Is there a lens I need that will focus everything no matter how far or close? Or is that a setting I need to work with?

Thanks

 

[JR6ooo4]

Ok, I have the kit lens 18-55 and a 50 lens as well.
Now, something I notice is, no matter what I shoot, the target will be clear as day, but anything a lot closer or farther will be a bit blurry. Is there a lens I need that will focus everything no matter how far or close? Or is that a setting I need to work with?

Thanks

if you shoot in aperture (A) mode then you can choose the depth of field. A smaller number will return the shortest DOF. Larger numbers have a deeper DOF. But, here is the confusing part, a small number means a big opening in the lens. Large number is a small opening which lets less light in so the shutter must stay open longer for the same exposure level. So much longer that you may need to stabilyze the camera by setting it on something or using a tripod or monopod.

SLR cameras get great DOF effects but the point and shoot cams get a deeper DOF which results in more of the picture in focus.

Mikeeee

 

[tinksdad]

To add; different lens have different DoF, zooming out reduces or compresses the DoF as well.

Here is a pretty good link that explains it pretty well. A bit technical, but good.

 

[photo_chick]

A pinhole camera is the only one I can think of where everything in the frame is in focus. There are tutorials online to make a pinhole lens for your camera. Or you can just buy a pinhole camera. Tehy are a lot of fun to use and there are some around that use 35m film.

 

[AKLforever]

Ok. Let me ask this, see if what im reading is right here.
Ok, seeing as I have a kit lens and a 50mm lens, one wiht a f/1.4 and the other with a f/3.5 to f/5.6, but still wanting more total picture focue, something to almost if not completely eliminate depth of field, would I have to go higher to maybe a f/8 zoom lens of maybe up to 100 or 200?
Would that help some more?

 

[boBQuincy]

With any lens, at any aperture, only one plane is ever in focus. Such is the physics of optics.
*However*, an area of acceptable focus exists in front of and behind the plane of focus. The depth of this area increases as the aperture is stopped down (toward f/22 or whatever the smallest aperture is) and it also increases as the focal length of the lens gets shorter (toward 18 mm or whatever is the shortest the lens goes to).

By setting any given lens to it's shortest focal length *and* by setting said lens to it's smallest aperture, the depth of field will be maximized. In your case, kit lens at 18 mm and f/22 (or f/32 if it goes to that).

Pinhole cameras get around this because nothing is in sharp focus, but everything is in the same somewhat acceptable focus.
P&S cameras do better because their lenses focal lengths are so short.

 

[AKLforever]

Ahh, so that makes more sense to me then.
Thanks

 

[handicap18]

Getting the deep depth of field is a matter of settings. Typically f/16 to f/22 and smaller will give you more depth of field. Think of it as squinting your eyes. You may notice people that wear contacts or glasses will squint a lot when they are looking at something (I wore glasses and/or contacts 25+ years till I had lasic surgery so I know a little bit about the squinting thing to get something in focus).

There is actually more math behind it involved. Where you focus relative to the lens you are using will also make a difference. But I forget the math to figure it out exactly (I think most people don't bother with it). I usually focus on something about 1/4 down from center or up from the bottom and use a small aperture.

"Understanding Exposure" by Bryan Peterson has a great chapter on aperture. He breaks it down to 3 area's. Shallow (blury background,, f/1 - f4), Who cares (f/5.6-11) and deep (f/16 and smaller). Not the exact terminology but pretty much the premise.

 

[Groucho]

Ok. Let me ask this, see if what im reading is right here.
Ok, seeing as I have a kit lens and a 50mm lens, one wiht a f/1.4 and the other with a f/3.5 to f/5.6, but still wanting more total picture focue, something to almost if not completely eliminate depth of field, would I have to go higher to maybe a f/8 zoom lens of maybe up to 100 or 200?
Would that help some more?

Others mostly answered this, but in case you didn't catch this yet, the F-number listed with a lens is the minimum F-number, they can go much higher, usually up to 22 or so. Most lenses don't operate at their peak at one extreme or the other... usually F8 or maybe F11 is the most you'll ever need unless you're trying for something really specialized.

FWIW, the Zenitar 16mm fisheye lens can have sharp focus on everything past about 2.5 feet... that's a fun lens.

I don't have my camera in front of me so I'm not sure about the kit lens, but I know the 50mm has markings that will tell you how much you'll have in focus at any given time. If you look at the top of the lens, there's a window that shows you the distance that you're focusing at, in feet and meters, going up to infinity. Just under the window, you'll see sets of lines on either side of the center, and on the left, they're marked 22, 16, and 8. Those lines tell you how much you'll have in focus at any given time. At F8, your range will be between the line on the left marked 8, and the matching (unmarked) line on the right. F16 has more in focus at once, so the range is greater, and so on.

You can use these markings to get an actual idea of just how much will be in focus. There are no markings for F-stops faster than F8 because they'd be too close to read easily... but you can just of guesstimate where they are.

 

[photo_chick]

FWIW, the Zenitar 16mm fisheye lens can have sharp focus on everything past about 2.5 feet... that's a fun lens.

Do they make it in an EOS mount???? (thinking to self "do I REALLY need to replace the mainseal in the Camaro?")

I just googled and ebayed.... I'm thinking Mother's Day is tomorrow....

 

[boBQuincy]

Do they make it in an EOS mount???? (thinking to self "do I REALLY need to replace the mainseal in the Camaro?")

I just googled and ebayed.... I'm thinking Mother's Day is tomorrow....

Yep, the Zenitar 16 comes in a Canon EOS mount *but*... it is a fully manual lens so the camera has no idea it is there, at least for the purposes of aperture and focusing. I usually use the Zenitar in Av mode and the EXIF data shows f/0!
It's a fun lens for not much $$$.

And yes, you need to replace the mainseal, Camaro's deserve good maintenance.
http://www.mindspring.com/~bobquincy2/vehicles/bobsrides.html

 

[photo_chick]

And yes, you need to replace the mainseal, Camaro's deserve good maintenance.
http://www.mindspring.com/~bobquincy2/vehicles/bobsrides.html

Yeah, it is a 99 and we figured when it was spared in the last big storm (basketball goal just missed it) that it was a sign we should get it fixed rather than trade it in.

Found the lens online, flirting wiht ordering it.....

 

[AKLforever]

Groucho, that fisheye lens, you say it makes everything in focus after 2.5 ft or so. But does it do anything odd to the picture? Or does the picture still look normal? That does sound like the lens Im looking for.

 

[jann1033]

sorry op, not trying to hijack but 2 questions about the fish eye...1 when you say manual , how would i go about using it on my camera( rebel xt...i have to have done this before in the olden days of my far removed youth but sure do not remember how) guessing it must have aperture ring or something on the lens it self? and just to show how poorly my brain is working forgot ?2 so i'll have to post that later ( this really is a honest to goodness brain defect i have and not just total stupidity)

and this would not be wide enough to be fish eye on 1.6 or would it? what is the ca etc like if anyone has a photo taken with it?

 

[boBQuincy]

To answer the two previous posts:
yes, the Zenitar 16 is a fisheye lens and some fisheye effect shows up even on a 1.6x crop camera. It is usually not noticeable unless there are straight lines in the subject. Buildings and interiors definitely show some fisheye but most of it is easily corrected in an image editing program.

The manual part means the lens is always stopped down to whatever aperture it is set to (via the aperture ring on the lens), darkening the image in the viewfinder. In practice this isn't usually a big deal since focusing is almost optional on a lens where at f/4 everything from about 1.2 meters to infinity is in acceptable focus.

CA and sharpness are good on the one I bought, although quality seems to be variable on these lenses. Mine arrived in a brown paper wrapper, tied with string, and decorated with Ukrainian text, so it's not just inexpensive, it has style too!

 

[handicap18]

Groucho, that fisheye lens, you say it makes everything in focus after 2.5 ft or so. But does it do anything odd to the picture? Or does the picture still look normal? That does sound like the lens Im looking for.

sorry op, not trying to hijack but 2 questions about the fish eye...1 when you say manual , how would i go about using it on my camera( rebel xt...i have to have done this before in the olden days of my far removed youth but sure do not remember how) guessing it must have aperture ring or something on the lens it self? and just to show how poorly my brain is working forgot ?2 so i'll have to post that later ( this really is a honest to goodness brain defect i have and not just total stupidity)

and this would not be wide enough to be fish eye on 1.6 or would it? what is the ca etc like if anyone has a photo taken with it?

Groucho does have pictures with this lens both with a dSLR and a film slr. The CA is much more prounounced with film and looks very cool. It is there with the dSLR and you can tell it was most likely with a fish eye, but because of the crop factor it isn't like it would be with film.

Jann you would have to set the aperture yourself, it does have an aperture ring, however, I don't know if you set the aperture with the lens or on camera. I'm guessing that it would be on the lens since the camera wont really recognize it.

I've thought about getting one myself, however the view finder on the D50 is really the only thing I don't like (smallest of all the current Nikon dSLR's). It is small and doing manual focus isn't as easy on my film slr or other newer dSLR's with a bigger view finder. I have it on my list of lenses, but its not near the top. Maybe one day when I need to get a new body I'll get this lens then.

 

[jann1033]

sounds like my singapore manual $10 extension tubes..unfortunately the packaging was the only good part about those and not really worth $10 although i wonder if i could use them with that lens since i could control the aperture manually

 

[boBQuincy]

I don't usually bother trying to focus the Zenitar 16 through the viewfinder, I just use the focusing scale on the lens. If it set to f/8, where I normally set it, just about everything is in decent focus anyway.

I did try it on "Pirates" at f/2.8 with the focus set to about 20', and most of the images were acceptable.

Btw, I carry a tiny LED flashlight with a red LED for use in dark places, it is probably not noticeable to anyone and can be a big help in case I have to change a setting in the dark.

 

[Groucho]

Looks like most of the questions were answered already.

The place I bought it from, straight from Russia (via eBay seller "zenitar"), does not have an EOS mount, only Pentax K and M42 (screw-mount) and Nikon. Most eBay sellers selling it for Canon take the Pentax M42 mount and put on an M42-EOS adapter to allow it to mount. I think I have seen one or two who claim that they have a native EOS mount... it doesn't really matter, it should work the same whether it's a native mount or an M42-EOS adapter. I recently found this page which has side-by-side shots of the Canon 50mm F1.8 Mk1 vs an M42-mount Pentax 50mm F1.4, both on a Canon DSLR... this gives a very clear indication of why an M42 adapter might be a nice thing to have anyway.

It is 100% manual no matter what the mount is, no "A" setting on the aperture ring.

Focusing is generally not an issue because of the range of stuff. The only time you'll need to focus is if something is really close to you.

Part of the fun is the Russian packaging, instructions, etc:

Here's how a shot looks on my 1.5-crop DSLR: (Grand Floridian)

Here's a shot with the same lens on my 35mm film SLR: (this is underneath Tomorrowland Transit Authority)

On the 35mm, you get a full 180' fisheye photo. (You have to be careful to keep your feet out of the photo!) On the DSLR... something closer to 110' or so, I'm not sure about the exact number. Even so, it is still a fisheye, so you'll get the curved edges. If you want to, you can often compose your photo so that you hardly notice the fishy effect. I also found that it worked great for on-ride photos on Big Thunder Mt RR because so much was in focus and the lighting was pretty consistent.

Splash Mt didn't work as well as I was trying to change the exposure while going from inside to out and I didn't always have time to get it right (like on the final drop, where I got a little overexposure.) On the Pentax, you shoot in Manual mode and hit the AE-L button, which quickly stops down the lens and takes a meter reading to set the exposure. I think the procedure is basically the same on other cameras. But that last Splash Mt drop was tough since you go from darkness, into clear sky, then straight down into the briar patch, each of which requires a different exposure.

Going back to the focus thing, I just took a quick photo of the lens's markings to show just how much it can focus on at once.

Remember we were talking about the distance scales? Well, in this pic, I've lined up the focus so that it should focus to infinity when set to F8. (Look at the green markings, those are the F-stops... the line from 8 points to infinity. On the other side of the red focus mark, the other 8 points to just right of the 0.6 meter marking, we'll say it's about 0.7 meters, or about 2.3 feet. That means that at F8, everything from 2.3 feet to infinity should be in focus. Go all the way to F22, and everything from less than a foot to infinity will be in focus... not too shabby.

The other thing to note about the lens is that it's relatively heavy for the physical size of it. It does feel pretty sturdy, though, and works smoothly, at least mine does. Overall, it's really a lot of fun for a pretty reasonable cost. I would like to eventually get one of the Pentax 10-17mm lenses (which are rebadges by Tokina and sold in other mounts), which at 10mm, give the full 180' on a DSLR, but even with a $100 rebate, it's still at least 3x the cost.

Oh, and because it's so "basic" (technically speaking), you don't get any exif data from the lens, so your focal length and aperture are not recorded. I have come up with a pretty easy way to add the focal length to your photos, though, if anyone's curious.

 

[cpbjgc]

Here is a link someone else posted here previously (Can't remember who it was) which shows the area of focus for different camera bodies at specific focal lengths and apeture settings. It might help you out (I know I found it useful!).

Online Depth of Field Calculator