The GetDPI Photography Forum

Great to see you here. Join our insightful photographic forum today and start tapping into a huge wealth of photographic knowledge. Completing our simple registration process will allow you to gain access to exclusive content, add your own topics and posts, share your work and connect with other members through your own private inbox! And don’t forget to say hi!

DP1 hyperfocal distance

andrewteee

New member
In a thread here on GetDPI I found these for the DP1 hyperfocal measurements:

f4.0. 12.6'
f.5.6 8.93'
f8.0. 6.33'
f11. 4.49'

In practice, what does this mean? At F/4 you should, in general, focus 12.6 feet away for optimum image sharpness within the depth of field? Does this mean that I can set the manual focus wheel to approximately 12.6 feet and most shots will be in focus. Does this have anything to do with zone focusing?

I've Googled hyperfocal distance and I still don't grok it. Perhaps I'm just dumb :eek: Any helpful hints or clarity appreciated! Thanks.
 

Streetshooter

Subscriber Member
That's from my post and it translates like this....

if you focus at the hyperfocal distance then,
the DOF, (Depth of Field) will be from 1/2 of the hyperfocal distance to infinity.

any questions ya can call me in the USA @ 267-784-4042
 
Last edited:

andrewteee

New member
Thanks Streetshooter! So doing the math, at F/4 if you focus on approximately 12.6 feet from the camera the depth of field will be from around 6.3 feet to infinity?

I'm very visual and have a hard time making sense of word descriptions of such things. But I think I get it now.
 

Will

New member
Another question.

Why in that case doesn't the camera simply focus at 12' 6" when you set the focus to infinity since the lens has a maximum aperture of f4.0? Or does it in fact do that? On the manual focus shown on screen it goes from 7' then almost straight away to infinity. Maybe the infinity setting is at 12' 6"
 

Streetshooter

Subscriber Member
Will,
That's a good question and you actually answered it to yourself...it appears that is in fact what the camera does....

On a camera lens, you take the infinity mark and put it at the fstop you are working at...now your focused at HD....with these digicams..it's difficult to do that...the DP1 compounds the issue by only doing meters...good for you guys but usin's in the

new Colony called the USA..we like feet...it's a foot fetish we can't translate to meters....Luckily the camera has a short lens so there is much forgivness but with the new DP2 coming out...this will be a big issue especially with a finder......
 

Streetshooter

Subscriber Member
Thanks Streetshooter! So doing the math, at F/4 if you focus on approximately 12.6 feet from the camera the depth of field will be from around 6.3 feet to infinity?

I'm very visual and have a hard time making sense of word descriptions of such things. But I think I get it now.
Just take the camera outside.....make a few exposures....

1 at infinity....
1 at hyperfocal

do this for each f stop and you'll get it right away......
 

fordfanjpn

Member
Another question. When you calculate the DOF, do you use the actual focal length of the lens, i.e. 16.6mm for the DP1, or the 35mm equivalent focal length, in this case 28mm? I'm guessing that you use the actual 16.6mm focal length, but I'd like to confirm that.

Bill
 

Will

New member
Streetshooter, the latest firmware update for the DP1 enables the camera to show both metric and imperial measurements on it's screen :)
 

Streetshooter

Subscriber Member
Another question. When you calculate the DOF, do you use the actual focal length of the lens, i.e. 16.6mm for the DP1, or the 35mm equivalent focal length, in this case 28mm? I'm guessing that you use the actual 16.6mm focal length, but I'd like to confirm that.

Bill
Bill, you have to use the actual focal length of the lens. The DOF calc gets it to 16mm not 16.6...who cares...it's close enuff...I have that program in my Iphone....

see it online here....
http://www.dofmaster.com/dofjs.html
 
Last edited:

Streetshooter

Subscriber Member
Streetshooter, the latest firmware update for the DP1 enables the camera to show both metric and imperial measurements on it's screen :)
Will, yes it does but if you look at it....

it's accurate to 3' or about 1 meter...then it goes to some uneven spacing...

it's actually ok on the 28mm lens but it won't work the same on the 41mm.
I'm sure the Sigma people took that into consideration.....well, not sure but let's hope so....
 

gromitspapa

New member
Question- is focus equally sharp within a given DOF? For example, at f/4 and focused at 12.6', is an object at 6.3' as sharp as it would have been if the camera was focused on the object itself?
 

Michael S

New member
Based upon my experience, the answer is no -- not "equally sharp."

But often, acceptably sharp for my kind of shooting, principally consisting of street snaps.

I should add that I've never used the DP1, but I do at times pre-focus another compact digital, an older Canon model, to a preset distance to minimize lag. At wide angle, this has worked well. Keep in mind that the d.o.f. is extensive with all the small sensor cameras at wide angle. I think of the DP1 as a compact, but not truly a "small sensor" camera, for the reason that its sensor is ... not small.;)

A number of my street snaps are here:

http://www.flickr.com/photos/michael-s/

Incidentally, a very accomplished N.Y. street photographer named Markus Hartel (he's in another class, and that is *not* false modesty on my part) has used a DP1 very effectively for a number of his shots, and I believe he focuses it manually. I'll look for the post in which he describes his approach to the DP1, but meantime, here (if I've done it correctly) are some of his DP1 photos:

http://www.flickr.com/search/?q=dp1&w=77314462@N00

Just now located Markus' comments about the DP1. They are on this (long) thread, and you can scroll down to the post by Markus Hartel to read them:

http://photo.net/digital-camera-forum/00PXHf
 
Last edited:

smokysun

New member
thanks for the link to markus photos. makes me think, forget street stuff, others have done it much better! and though i've made more than a dozen trips to nyc and spent more than three years there, it doesn't have the old appeal. guess i'm getting old.

wayne
www.pbase.com/wwp
 

Will

New member
This discussion is reminding me of an observation in another forum some time ago where the difference between the infinity setting and manual infinity gave slightly different focus for landscape work. The conclusion was that to get the sharpest detail in the horizon it was best to use manual focus. I think it was a GX100 or GRD2 camera being talked about. This now makes more sense if in fact the manufacturers do use the hyperfocal principal for their infinity setting.

Some test shots would be interesting if someone has some good clear weather conditions available.
 
Top