Minimum Focus Distance: iPhone 4S

[jseye]

I've been wondering about the minimum focus distance of the 4S for a while now. Apple is curiously silent on the subject, for such a critical spec. Very curiously silent to my mind, as The Jobs was a king hell detail freak. Made me wonder. On the net one finds a lot of categorical statements - nonetheless using the word "about" - that go from 2" to a foot (or so). No pictures, of course, or objective standard of just what "in focus" was. Made me wonder even more . . .

So I scratched that itch tonight.

I set up my highly sophisticated test lab (my desktop) and found an ordinary business card with very crisp printing when viewed through a 10x loupe. Plugged the earbud into the 'phone for remote (vibration free) shutter actuation. Put some adequate light on the subject.

Then I took shots at 6, 8, 10, 12, 14, and 16 measured inches. All shots were taken with 645PROMkII and are completely unprocessed TIFF. Point of focus for all shots was the name "Nigel". I then took a detail crop of the lettering from each pic in an extravagance of pixel peeping.

These were the results:

6" -

8" -

10" -

12" -

14" -

From 14" and on up I'd say that the pics - even with my poor old worn out eyes - were in reasonable focus. Below 14"? I'd say not.

So . . . either I have an out- of- spec camera or . . . The chatter about minimum focus of the 4S is urban myth.

Either way, I now know what my camera will do, and won't, which is all that mattered to me in the first place.

I'd be curious what other 4S shooters on this forum consider min focus on their own cameras.

R'gds,

John

 

[Smooth]

Very interesting experiment John - I very much appreciate you taking the time, and patience! Nicely setup too.

If you ever need to get up close and personal, macro style, I'd thoroughly recommend the Olloclip if you don't already have one.

I'm going to put this out across our social media - awesome thread.

 

[jseye]

And my thanks to you, Smooth; be interesting to see what feedback there might be,
Something I forgot to mention in my first post is that I repeated the series four times with no discernible difference in the results, so it would appear that there is no irregularity of lens function to throw the results out of whack.

R'gds,

John

 

[Lzed]

While I have not done tests like you have I thought it focused closer.
I took these today

Both are from less then 8" with my iPad 3 and my old eyes they look sharp.

Now you got me curious so I may have to try some tests myself

 

[RoseCat]

What a cool experiment... Something I wouldn't have thought to do. Thanks for sharing this John!

 

[lookingGlass79]

To me it appears that the point of focus is actually the yellow wall behind the card and not on the card itself. I'd like to see this same experiment done with the iPhones native camera though, and the point of focus set by actually tapping the exact spot you'd like it to focus. I know my own iPhone 4 has done some very crisp focus from 5-6" away from subjects, such as Larry's flower photo. Just my own observations. The picture below is taken with native iPhone 5 camera, which has the exact same specs as the iPhone 4S, zero zoom just up close to the subject...within 4-7" at least and I think this sharpness is amazing! Totally nekkid image btw, I remain very impressed with the iPhones capabilities and very pleased, eager for the new iPhone too!!

 

[lookingGlass79]

 

[MuzzMelbourne]

I agree. This was taken with the native camera from about 4" away. There is enough detail to show the scetchy printing with blurred foreground and background.

 

[Lzed]

To me it appears that the point of focus is actually the yellow wall behind the card and not on the card itself. I'd like to see this same experiment done with the iPhones native camera though, and the point of focus set by actually tapping the exact spot you'd like it to focus. I know my own iPhone 4 has done some very crisp focus from 5-6" away from subjects, such as Larry's flower photo. Just my own observations. The picture below is taken with native iPhone 5 camera, which has the exact same specs as the iPhone 4S, zero zoom just up close to the subject...within 4-7" at least and I think this sharpness is amazing! Totally nekkid image btw, I remain very impressed with the iPhones capabilities and very pleased, eager for the new iPhone too!!

Yes! Look at the detail in the paint especially by the curtain, it appears to have been the focus point.

 

[lazaro]

Really interesting experiment. Cinematographer? I wonder what Mike Hardaker would say about the MKII's focus capabilities because, as lookingglass noted, that's really what's being tested here. Also, based on Lzed's, hipstamatic photos his focus seems to be different from MKII and Native camera. So I wonder if it's not that each app has a totally different focal point? That's impressive considering they all use the same sensor. I think the closest I feel comfortable going for portraits or macro (without using an attachable lens) is actually with hipstamatic, in particular with the Loftus lens. It uses the facial response tech of the Iphone's sensor to really focus in from short distances in ways I haven't been able to with any other app (hats off to hipstamatic for this.) The Tintype lens works the same way, but I find it too extreme and too accidental for any practical purposes. Eyes become demonic with that thing.

 

[mwolfer]

Thanks everyone for the info ... very interesting!

 

[lisamjw]

Excellent experiment and follow-up discussion!

 

[jseye]

Excellent experiment and follow-up discussion!

Folks -

All your great feedback gave me some more food for thought, with the result that I changed my setup just a bit. In order to eliminate the background/focus variable, I took a piece of white 1" styrofoam board and pinned the business card to it; that way, the camera had no choice in its focus and as card and board were effectively in one plane, no depth of field issues. I then ran the same test procedure as the first time using both 645PRO and Apple's native "Camera" app. I used Apple's screen-tap function to achieve best point-of-focus per your feedback.

Here are the images (I am posting only the 6" and 14" views for reasons that will be immediately apparent). Note that the images are posted in pairs: 645 followed by Apple.

645 @ 6"

"Camera" @ 6"

645 crop @ 6"

"Camera" crop @ 6"

645 @ 14"

"Camera" @ 14"

645 crop @ 14"

"Camera" crop @ 14"

The results with regard to focus - at least to my eyes - are virtually indistinguishable. Apple's "Camera" app seems to have a very slightly larger field of view, but that's about it. In both cases, 14" seems to be the minimum
focusing distance.

Sooo . . . the affair gets "curiouser and curiouser" as Alice was wont to say.

I'll say again that this has nothing to do with "my phonecam focuses closer than yours" bragging rights, which are intrinsically meaningless. Every camera is a set of systemic compromises; the more complicated the camera, the more extensive the compromises. All this test set out to determine was a reasonably empirical measurement of the minimum focus distance of a 4S. Which seems to be 14" in this case.

But I still wonder why I cannot find any mention of this piece of data anywhere in the Apple universe . . .

R'gds,

John

 

[Lzed]

Maybe I will set something up tomorrow and try it with my iPad 3 and see what it does.

 

[lookingGlass79]

I had to go ahead and do my own test now. I believe my set up should be very similar to the way the previous test was set up. I put my iPhone 5 onto a tripod, and used a Belkin Camera Remote to snap the pictures so there's no camera shake. Used a good ol wooden yardstick to make the measurements. And I only used the iPhones native camera app. Again, as stated before, the iPhone 5 and iPhone 4S have exact same camera specs according to the website. I did the touch screen to focus, and the focus point of every picture was the name Harrison. I began at 3" and only went to 8" as I believe this proved well enough the cameras focus abilities. I'm not sure how old the iPhone is that was used in the previous test, if it might have been dropped and/or repaired, which could mess up the lenses and the focusing capabilities....but there does seem to be something off with your iPhone cameras ability to focus at close range, that other iPhone 4S and 5's aren't having apparently. Maybe you should have Apple check it for you. Hope this helps.

First picture is just to show how I set up for this test.

Taken at 3" focused on Harrison

4"

6"

8"

 

[Lzed]

Well I tried my iPad 3 a few minutes ago. I only did the 4" for the simple reason that to my eyes it is very clear at 4"

I want to find some way to do closer. This card was taped to my iMacs screen and with the base of my stand for the iPad right up against the base plate of the iMac it was right on 4" so I couldn't get closer. I will figure something out and see what 3" and 2" comes out looking. Tried to make sure that card was taped at the Center of the lens and make sure that the camera is square to the iMac.

Hipstamatic, Labatique, Kodot Xgrizzled no Flash set

This picture is 645 Pro II tapped on the word Bus to set focus for both this and following image.

This is the standard app that came on the iPad (that I have not used in a very long time)

T o my eyes the 645 picture is the sharpest and for this it was set to the default jpg setting, not tiff which in other tests I thought was even sharper....

I think it was Brandy that suggested that maybe your camera needs to be looked at!