Newbei bought a 35mm without VR

[Ron Evers]

I am pleased that some folk more familiar with the OPs equipment than me are trying to help out as I use a mirror-less camera & manual lenses.

 

[Josh66]

How close can that 35mm focus?

You may want to do these sort of test close to the closest focus the lens can do on such a wide lens (not right at the limit, but close to it), just to make the results easier to see - and also it should make everything more critical, which will also make any errors more obvious.

 

[Ron Evers]

Thanks Josh, I have now passed the ball.

 

[Josh66]

Thanks Josh, I have now passed the ball.

 

[RichardsTPF]

f1.8, with flash, sorry I don't have a ruler. spot focus at 21".

[/URL] DSC_0043_50 by RichardsFlik, on Flickr[/IMG]

Looks like focus is good. No back.front focus issue.

 

[Josh66]

To me, the 21 1/8 inch line looks the sharpest... So, if that is the case, and you focused perfectly, that lens would be front-focusing by about 1/8".

Not much, but if you're shooting wide open, every little bit counts...

 

[kundalini]

To me, the 21 1/8 inch line looks the sharpest...

Me too.

Make life easier on yourself Richard. Learn about proper focus testing and print a proper chart. You can read more about it here...... Focus Testing - photo.net

 

[RichardsTPF]

Yes. It's 0.177" off. Is that normal for a new camera?
Do you think that cause the blur image? When I shoot f4 at 5', I can move my camera forward little bit.
when we calculate DOF, where shall I start measure the subject distance from, the front of the len or the camera body?

 

[Josh66]

I guess it's possible that the camera focused on the '1' instead of the line at 21". Focusing on the line, the AF point box surely covered part of the '1'. Who knows how small of an area it really focuses on...

It might be worth repeating the test using manual focus... (Make sure the diopter is adjusted correctly first.)

 

[Josh66]

where shall I start measure the subject distance from, the front of the len or the camera body?

It is measured from the film/sensor plane. There should be a mark on top of the body somewhere (usually close to the flash/prism) - it looks sort of like a diameter sign - ⌀ (but the line will be longer). The line is the film/sensor plane. This is where you measure form.

edit
If you can't find a mark like that on your camera, measure from the back of your camera and subtract 1/4" or so (the exact amount will vary based on how your camera is built, but 1/4" should be pretty close).

 

[RichardsTPF]

diopter? never used. I double check the focus point. I made a stupid mistake. No wonder the 21 1/8" is most in focus. Here it is.

[/URL] DSC_0044_01 by RichardsFlik, on Flickr[/IMG]

 

[RichardsTPF]

I will redo it.

 

[Josh66]

diopter? never used.

You don't even need a lens on for this...

Look at the viewfinder - right next to it (you might have to remove the rubber eye-cup) there should be a little wheel...

Look at the markings in the viewfinder (AF boxes, and such) - adjust the little wheel until those viewfinder markings are the sharpest.

 

[RichardsTPF]

Here are AF-S, exact 5' from ⌀ to the bar code. AP, ISO800
#1 f2.8, 1/25s

[/URL] DSC_0052 by RichardsFlik, on Flickr[/IMG]

#2 f4, 1/13s

[/URL] DSC_0053 by RichardsFlik, on Flickr[/IMG]

#3 f5.6, 1/6s

[/URL] DSC_0054 by RichardsFlik, on Flickr[/IMG]

#4 f8, 1/3s

[/URL] DSC_0055 by RichardsFlik, on Flickr[/IMG]

#5 f11, 1/1.6s

[/URL] DSC_0057 by RichardsFlik, on Flickr[/IMG]

 

[MTVision]

Here are AF-S, exact 5' from ⌀ to the bar code. AP, ISO800
#1 f2.8, 1/25s
[/URL] DSC_0052 by RichardsFlik, on Flickr[/IMG]

#2 f4, 1/13s
[/URL] DSC_0053 by RichardsFlik, on Flickr[/IMG]

#3 f5.6, 1/6s
[/URL] DSC_0054 by RichardsFlik, on Flickr[/IMG]

#4 f8, 1/3s
[/URL] DSC_0055 by RichardsFlik, on Flickr[/IMG]

#5 f11, 1/1.6s
[/URL] DSC_0057 by RichardsFlik, on Flickr[/IMG]

Handheld? Tripod?