Become a MacRumors Supporter for $50/year with no ads, ability to filter front page stories, and private forums.

Caliber26

macrumors 68020
Sep 25, 2009
2,325
3,637
Orlando, FL
Thanks for sharing!

I loved your "Street Lights" pictures, by the way. I'd love to see a tutorial on how you processed those!
 

odagled2004

macrumors newbie
Aug 3, 2011
28
0
Wow. I actually learned a lot. I seen your videos before but never really paid attention. This one was really well explained! Thanks a lot! You've gained a subscriber.
 

BanjoBanker

macrumors 6502
Aug 10, 2006
354
0
Mt Brook, AL
I spent hours trying to explain DoF to my daughter who is taking a photography class in college. ( they are using film!) I wish you had posted this before I wasted my time! This is excellent and I hope you don't mind, but I sent a link to this posting to her photography teacher. This is so much clearer than her explanation. Thanks for the great video, keep them coming...:)
 

blanka

macrumors 68000
Jul 30, 2012
1,551
4
Please include the technical background:

At the SAME APERTURE, WITH THE SAME REPLICATION FACTOR, ALL LENSES HAVE THE SAME DEPTH OF FIELD!

This REPLICATION FACTOR is the most important factor in DOF, and nothing else!

You will see instant why it is easy to get a landscape scene tack sharp front to back, yet why it is really hard to get that bug in macro totally sharp.
 

dipm06

macrumors member
Original poster
Jul 28, 2009
88
0
Please include the technical background:

At the SAME APERTURE, WITH THE SAME REPLICATION FACTOR, ALL LENSES HAVE THE SAME DEPTH OF FIELD!

This REPLICATION FACTOR is the most important factor in DOF, and nothing else!

You will see instant why it is easy to get a landscape scene tack sharp front to back, yet why it is really hard to get that bug in macro totally sharp.

Replication factor? I'm not sure what you mean by that, but I do mention that subject distance from that camera affects DoF. I'm assuming that is what you're talking about. I also go in to show how it works by focusing on a subject up close and then moving the camera back.

----------

Wow, this explains it so easily. Perfect timing as I move up the camera learning rungs with my newest camera. Thanks so much for this!

Thanks! I have a bunch of other tutorials on my channel that you might like!
 

blanka

macrumors 68000
Jul 30, 2012
1,551
4
Replication factor is the factor of object diagonal/sensor diagonal

So a head with 25 cm diagonal corner to corner on a chip of 45mm diagonal (FX) in focus, will have the same DOF for out of focus elements NO MATTER WHAT FOCAL LENGTH lens you take this pic with (the same framing). So the DOF is the same if you make it with a 28mm or with a 300mm (at the same aperture). The DISTANCE to the subject is different off course. You must take this pic at 30cm with a 28mm, and at 3m with a 300mm.
 

acearchie

macrumors 68040
Jan 15, 2006
3,264
104
Replication factor is the factor of object diagonal/sensor diagonal

So a head with 25 cm diagonal corner to corner on a chip of 45mm diagonal (FX) in focus, will have the same DOF for out of focus elements NO MATTER WHAT FOCAL LENGTH lens you take this pic with (the same framing). So the DOF is the same if you make it with a 28mm or with a 300mm (at the same aperture). The DISTANCE to the subject is different off course. You must take this pic at 30cm with a 28mm, and at 3m with a 300mm.

This is complete trash. At f2 on a FF camera 28mm at 30cm will have 1.25cm total DOF whereas the 300mm at 3m will have 1.08cm total DOF.

Have you just made this up?
 

dipm06

macrumors member
Original poster
Jul 28, 2009
88
0
Replication factor is the factor of object diagonal/sensor diagonal

So a head with 25 cm diagonal corner to corner on a chip of 45mm diagonal (FX) in focus, will have the same DOF for out of focus elements NO MATTER WHAT FOCAL LENGTH lens you take this pic with (the same framing). So the DOF is the same if you make it with a 28mm or with a 300mm (at the same aperture). The DISTANCE to the subject is different off course. You must take this pic at 30cm with a 28mm, and at 3m with a 300mm.

You don't really need to know at what distance a 28mm will have to be at to have the same DoF as a 300mm at a certain distance - not for real world use, at least. I think that knowing that having the subject closer will yield a much shallower DoF is sufficient enough. I think the examples in the video show it clearly.
 

DirtySocks85

macrumors 65816
Mar 12, 2009
1,441
82
Wichita, KS
Great video! I got my first DSLR 5 days ago, and I kind of understood this concept from other reading, but your video might be the best explanation I've heard on DOF so far.
 
Register on MacRumors! This sidebar will go away, and you'll see fewer ads.