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Himself
Joined: 01 Mar 2007 Posts: 3242 Location: Montreal
Expire: 2013-05-30
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Posted: Sat Jun 23, 2012 2:48 pm Post subject: |
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Himself wrote:
Interesting lens combinations Tobias!
My question is: why did you shoot at f/16-22?
At that magnification the difference between f/5.6 or f/8 and f/22 is unnoticeable DOF related.
Instead, you lose sharpness and contrast due to difraction. _________________ Moderator Himself |
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tobbsman
Joined: 25 Jul 2008 Posts: 2578 Location: Austria
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Posted: Sat Jun 23, 2012 3:56 pm Post subject: |
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tobbsman wrote:
@Himself
Quote: |
Interesting lens combinations Tobias!
My question is: why did you shoot at f/16-22?
At that magnification the difference between f/5.6 or f/8 and f/22 is unnoticeable DOF related.
Instead, you lose sharpness and contrast due to difraction. |
There're main 2 reasons for that:
- First reason: If I let the reversed lens at wide open, and I set the aperture of the
main lens between f2.8 and f 11: the flash diffuser will overexpose the
photograph. I already down regulated the internal camera flash
with -2.0 which is most I can do and set on ISO 100. I can't
do high speed flashing with the inbuilt camera flash, it's always set
to 1/180 with my cam.
So what to do against that: I can stop down the reversed lens to let less
light in. That's actually a solution and works, BUT viewfinder gets significantly darker
so working does get really awkward.
- 2nd reason and comment on your statement:
Quote: |
At that magnification the difference between
f/5.6 or f/8 and f/22 is unnoticeable DOF related |
don't underestimate DOF with macro photography.
it's there and it's a lot from what I can tell from my little experience.
check out this photograph, it's the only one from the series which was done at f6,3 (main lens)
and a little stopped down reversed lens to avoid to over exposing.
DOF is very thin there, just compare it to the others which were done at f16 and f22:
Cheers
Tobias _________________ Camera Pentax K10D, K20D, Super A
SMC K28 3.5, SMC K24 2.8, SMC K28/2, SMC K50/1.4,SMC A50/1.7, SMC M28/3.5, SMC A 50/1.7, SMC K135 2.5, SMC A50 1.2
SMC A35-105 3.5, SMC A70-210 4, SMC A20 2.8, SMC M28 2.8,K28/3.5 SMC A28 2.8, SMC A100 2.8 Macro, CZJ Flektogon 20 2.8 (MC), 35 2.4 (MC),S.M.C Takumar 85mm 1.8, Helios 44M-4, A.Schacht Travenar 90/2.8, C.Zeiss J. Sonnar 180/2.8
Check out my: 2012 New "Advanced Guide to Panorama Stiching" !
Check out my "Beginner's Guide to Panorama Stiching !
Visit my Asahi and Zeiss MF lens samples database ! |
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Himself
Joined: 01 Mar 2007 Posts: 3242 Location: Montreal
Expire: 2013-05-30
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Posted: Sat Jun 23, 2012 4:48 pm Post subject: |
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Himself wrote:
I see no difference. Even if there is a 1/20th of a mm difference, it doesn`t ad up to the image.
THE only way to have bigger DOF at that magnification is the stacking way. _________________ Moderator Himself |
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Aanything
Joined: 27 Aug 2011 Posts: 2187 Location: Piacenza, Italy
Expire: 2014-05-30
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Posted: Sat Jun 23, 2012 4:53 pm Post subject: |
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Aanything wrote:
I see some difference, actually.
On the other hand, DOF is really tiny even at f22, so, in many cases, focus stacking is necessary regardless of the aperture.
But I definitely see some difference between the one shot at f6.3 and the others. _________________ C&C and editing of my pics are always welcome
Samples from my lenses
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tobbsman
Joined: 25 Jul 2008 Posts: 2578 Location: Austria
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Posted: Mon Jun 25, 2012 8:33 pm Post subject: |
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tobbsman wrote:
@Himself
Quote: |
I see no difference. Even if there is a 1/20th of a mm difference, it doesn`t ad up to the image.
THE only way to have bigger DOF at that magnification is the stacking way. |
I think we still have very different opinions
Let me explain from my point of view,
(which is more based on my eyes then on science
... because I am not really into this Macro topic)
Just made some sample shots with one of this combos
(so one with a high magnification value, which is 4,2 : 1)
SMC A 100 /2.8 with a 24mm/2.8 on top
I did a comparison between f 5.6 and f22 on same subject,
same distance, angle lens to object = ~45°
I didn't made f2.8, because I think it's unusable because of
extreme narrow DOF
_____________
1 cent coin:
f5.6
f22
_______________
ruler: angle of view = 5mm
f5.6
f22
__________________
I think difference is obvious, so the argument
Quote: |
THE only way to have bigger DOF at that magnification is the stacking way |
is not really confirmed
I think you just overestimated the magnification with these combos. it's just ~4:1, so
I can still fill 5mm vertically on the frame with this combo.
____________
____________
My personal opinion about this stacking way:
there a 2 major disadvantages about it:
- it only works satisfying on not-mooving subjects
- one gets very limited and bulky with daily practise due to tripod use
For example:
with these type of shots that I showed here it is impossible to apply:
Just imagine these plants are up to 2 meters tall, so they are constantly in
motion. --> motion and stacking doesn't go along with each other.
(I know there are some crazy guys doing stacks on living animals, but I think
it's not a efficient way for daily use, especially with these
super-macro combos )
I am 99% of an outdoor photographer; when I am doing macros it's mostly
plants or living animals. So I was choosing for myself to be the stack way not my way.
I did once a stack with creeping grubs and it was hell of a work
to align and reconstruct this moving animals:
CZJ Flektogon 35mm/2.4
Cheers
Tobias _________________ Camera Pentax K10D, K20D, Super A
SMC K28 3.5, SMC K24 2.8, SMC K28/2, SMC K50/1.4,SMC A50/1.7, SMC M28/3.5, SMC A 50/1.7, SMC K135 2.5, SMC A50 1.2
SMC A35-105 3.5, SMC A70-210 4, SMC A20 2.8, SMC M28 2.8,K28/3.5 SMC A28 2.8, SMC A100 2.8 Macro, CZJ Flektogon 20 2.8 (MC), 35 2.4 (MC),S.M.C Takumar 85mm 1.8, Helios 44M-4, A.Schacht Travenar 90/2.8, C.Zeiss J. Sonnar 180/2.8
Check out my: 2012 New "Advanced Guide to Panorama Stiching" !
Check out my "Beginner's Guide to Panorama Stiching !
Visit my Asahi and Zeiss MF lens samples database ! |
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buerokratiehasser
Joined: 12 Jun 2011 Posts: 470
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Posted: Wed May 15, 2013 3:54 pm Post subject: |
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buerokratiehasser wrote:
yeah I made some of these 3:1 too
(the front of some lens, I believe Super Albinar, came off,
underneath a 50 mm or so thread which with a little force went into 49 mm or so I remember, was some time ago)
The ratios are impressive indeed, but it's really hard to focus and get the plane align with object, and DOF is nonexistent.
Also, the resulting contrast just sucks. |
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