50mm f/1.8 - DPChallenge Forums

Nikon AF-S NIKKOR 24-70mm f/2.8G ED

04/27/2006 02:06:58 AM · #1

Ok, I'll admit there's a whole lot of stuff I don't know about lenses.

Here's one that's puzzling me.

When I shoot with this lens on close-up subjects, I am able to get very sharp and accurate focus even in relatively low light. However, I find that when I get a little farther away, things really get soft very quickly. Even stopped down to f/5.6 or f/8. Even with focus. Even using hyperfocus at f/22. Even at 1/500.

I'm talking about a distance of around 20 feet and above.

Is this just a lens that is simply not designed to take pictures of things at any real distance?

Is it my camera?

I'm very busy this month, so I haven't had a chance to do a real exhaustive multi-distance focus accuracy check, but I believe that it's OK.

I will try to post some examples after I get home tonight.

hotpasta

Nikon D800

04/27/2006 03:26:24 AM · #2

apparently f22 is not the best aperture for these/most lenses...things get soft around there.

I believe around f4-f11 is the best range for mine (Nikon 50mm 1.8)

04/27/2006 08:57:04 AM · #3

Thank you. The problem is evident throughout the aperture range. I included f/8 as the 'sweet spot' for sharpness and the f/22 to indicate that I am quite sure that the focus was accurate.

100% crops coming soon. Sorry for the delay. I'm quite tired.

Ben

04/27/2006 10:12:18 AM · #4

What type of shots would you be looking at with this lens? Mainly portaits im assuming and macro with an extension tube? Is that right? Those are the two i'd be mainly interested in.

And can anybody tell me the difference between these two;
Canon 50mm f/1.8 II

Canon 50mm f/1.8 (MK II)

Thanks alot.

dwterry

Canon EOS-1D Mark III

04/27/2006 10:16:29 AM · #5

Originally posted by Kerm:

And can anybody tell me the difference between these two;
Canon 50mm f/1.8 II

Canon 50mm f/1.8 (MK II)

Pretty sure they are the same lens. They both have the II designation.

Ben

04/27/2006 10:26:21 AM · #6

Yeah, but there is a slight price difference aswell. Just confused me abit as i thought they were the same. Perhaps one is a newr version/model.

04/27/2006 10:26:28 AM · #7

As promised, 100% crops.

I am wondering if it perhaps might be missed focus.

I am also using a multi-coated filter on the lens by a Japanese company called Marumi. I am wondering if perhaps it is the problem. Sadly, there's nothing to test it on right now and I didn't think of this when I was testing. I was told that the filter is a decent quality one, just under the B&W filter.

I will check later. It doesn't seem to be a cause of issues, but it might be.

I am using the filter primarily because of the kids and the weather (rainy season has officially begun).

I tried to take some different perspective type pictures by lying on the ground as a line of kids walked past. Sometimes I wonder why kids think that it's a great way to get a picture taken of them by sticking their hands DIRECTLY on the lens. That ruined my opportunity completely. Kids.

Makes me glad I got the filter though :)

Here is the whole scene:

And the 100% crops:

I focused and metered on the flowers... I got almost identical results no matter what settings I used, so I think it will be OK using this as an example.

On the other side of the coin, I got

with the filter on at ISO 640.

Please note that while that picture IS sharpened, the sharpening in this area of the photo merely gently increased contrast. The definition of the lines of hair are present in the original almost exactly as shown.

This is a resize of the original

, I had to pause/edit this post because I can't find my original on that one. Yikes.

Message edited by author 2006-04-27 10:40:57.

Ampao64

04/27/2006 10:26:39 AM · #8

@kerm

Same lens, different supplier. Cheaper if you get the other one. :D

Ben

04/27/2006 10:32:31 AM · #9

thank you everyone.

P.s Sorry eschelar, i didn't mean to hijack your thread. :)

Canon EF 28-105mm f/3.5-4.5 II USM

04/27/2006 10:44:04 AM · #10

No problem. You saved me a bump :).

I am quite concerned about this sharpness issue as I have been asked to do a number of portraits for the school. I am inherently nervous of new things and tend to be a bit of a worrywort.

I hope this lens is ok.

Oh and btw, the lens is really cool. I don't use extension tubes as I don't have any yet. Taipei's camera stores all offer the same stuff. It's very frustrating getting anything unique or interesting here. I can't even get the reversing ring. I will have to go through B+H for that.

ReallyColorBlind

Canon EOS-70D

04/27/2006 11:57:27 AM · #11

Originally posted by Kerm:

According to the specs, the MK II has a filter size of 55mm. The other is only a 52mm.

fatLouie

Nikon D70s

Nikon AF-S DX Zoom-Nikkor 18-70mm f/3.5-4.5G IF-ED

04/27/2006 12:05:46 PM · #12

The non-MKII has identical optics, but is an older model. It is considered a great lense; it is metal instead of plastic.

Get the non-MKII if you can.

04/28/2006 10:23:38 AM · #13

Another bump in the hopes that I will get my original questions answered.

I would really like to know what is going on with my lens and if it is normal or what the problem is. At this point, I am considering that it may be a focusing error with a possible difficult to focus on subject.

On the other hand, I'm a little confused why it should have such an effect at f/22.

Is this a lens that simply cannot hack it when you pass an optimal distance?

Nikon AF Nikkor 50mm f/1.8D

04/28/2006 01:47:20 PM · #14

Last bump for this thread from me. I really would like to get some opinions and thoughts from others about my situation...

Thank you.

wavelength

Nikon D300

04/28/2006 01:59:08 PM · #15

I have not noticed the same, but mine is Nikon of course. I think your idea about your filter being the culprit is the most likely. If you take it off and the same still happens, then you know what it was.

For my part, I may run some tests tonight If I can.

Tamron 70-180mm F/2.8 Di III VXD

04/28/2006 02:22:46 PM · #16

Thank you. I will do that soon. I will finally get some time to shoot tomorrow.

Don't forget mirror lockup....

Some preliminary tests I made with my filter on and off handheld didn't show any real difference though....

MadMan2k

Sony Alpha a6400

04/28/2006 02:49:28 PM · #17

It's possible it might be just a little out of focus, but you're probably right about the filter.

Did you try adjusting sharpness when viewing at 25% or so? I find that it usually turns out alright if you adjust it there instead of at 100%, and then just resize (or even print). Plus I almost always shoot mine at f/1.8, just for the shallow DOF, and I've been pretty pleased with the results.

pitsaman

Canon EF 50mm f/1.8 II

04/28/2006 06:22:50 PM · #18

75 % human error !

Here is 50 mm at F16 bottom focusing point:

Message edited by author 2006-04-28 18:25:19.

Panasonic LUMIX-DMC ZS100

04/28/2006 10:39:24 PM · #19

Thanks for the words guys.

I do realize that the lens is sharp and can attain very sharp results close up. I am concerned about it's performance a little farther out.

Regarding the filter, it's not the most expensive filter, but it's not a terribly cheap one either. It is multi-coated and while it's a smaller name brand, that doesn't necessarily mean that it's junk. It was recommended to me from the actual owner of the store who was visiting just before closing. Japan puts out some peices of equipment that are of decent quality that may not necessarily have the name power.

Anyhow, I've got some time and, surprise surprise, some exceptionally flat lighting (overcast again?), so I'll try to take some shots today. Got some DISMAL sharpness through my 80-200 plus Kenko TC, but that could also be haze. Yech. I hope the air clears a bit soon....

wheeledd

Canon EF 24-105mm f/4.0L IS

04/28/2006 11:26:13 PM · #20

eschelar,

My thought was that your camera was not focusing as accurately at the longer distances. I looked carefully at TEST_100A_0250.jpg to see if there was evidence that the focus was not accurate.

What I saw does not support my idea--but it seems very strange. Look carefully at the place where the leaf on the right touches the brick near the center of the photo. This section of brick looks very sharp to me. But just to the left is the other face of the same brick. It looks very soft to me, even though it is the same distance from the camera.

Next I thought that it might be the lighting that brings out the texture of one face more than the other. But the brick above this one looks sharper on the left face than the right face.

I don't know what is going on here. It is hard to separate the characteristics of the lens from the characteristics of the scene. It would probably be easier to tell what is going on if you shot images of resolution test patterns.

--DanW

Panasonic LUMIX-DMC ZS100

04/28/2006 11:40:26 PM · #21

Thanks Wheel... I'm not sure where I can get resolution test pattern stuff. I've not seen any in any of the shops I've been to.

Nursing a bit of a cold, so haven't got around to shooting yet today. I still have time. I will be doing some tripod shots of my friend's camera for web sale, and at the same time, I will try to find something to shoot. I think I found a peice of paper that looks like it would do.

wheeledd

Canon EF 24-105mm f/4.0L IS

04/28/2006 11:50:17 PM · #22

eschelar,

I did a Google search for "resolution test chart" and found lots of printable charts. For instance, this page discusses resolution tests for video cameras and gives links to test patterns:

//www.bealecorner.com/trv900/respat/

--DanW

yido

Canon EOS-5D

Sigma 20mm f/1.8 EX Aspherical DG DF RF for Canon

04/29/2006 01:02:35 AM · #23

You're the second person that I've heard having this problem.
Sharp when subject is near but soft when the subject is far.

I think it's a problem with the lens/camera focusing issue, Can't say for sure though. If you really want it solved, I would repeat with a subject like the reoslution chart that is easy to focus on and repeat with a tripod and a cable release. If you are finding this repeatedly, my guess is that with distant subjects, the lens or the lens/camera combo is having focusing issues. Canon I hear likes to have you send the camera and the lens together so that they can calibrate them together in these types of situation. I haven't seen it in mine, but I rarely use mine.