DoF features : wishlist or stupid question ? your opinion ...

[Jules]

Hi,

Context: I have only started using fast lenses with nifty fifty 3 years ago, then bought 100 2.8 L Macro 2 years ago and finally pressed the button for the 70-200 2.8 L IS II last year (bundled with the 7DII) ...
Use case:
- I have been enjoying shallow DoF for portraits or nice bokeh (in macro/near field), but sometimes feel that my DoF is not fully optimized : face is sharp but part of the hat or necklace is not, that flying bee is a bit blurred in the back of that lovely rose, the bird is sharp from tip to tip but so is too much of his background and sometimes closing that much the aperture doesn't give me enough speed to freeze it (with decent ISO) ...
- Wanting shallow DoF for bokeh / quite open aperture for speed (bees/birds... ) so fighting to get just enough but not too much ... And in many situation (portraits in a parade, flying things ...) you cannot get a second attempt after checking it at x10 on the image once taken...
Disclaimer: I have been playing with DoF preview button, but i didn't find it super precise to make the distinction of sharp/beginning of blur, especially with the darkening of the viewfinder in not fully sunny days / inside ...
I never changed focussing screen though, a bit newbie on that ...
Idea of feature(s):
1) "DoF bracketing" : we have exposure bracketing, so i would propose similar feature where you can do say 3 or 5 shots, and vary aperture 1/2 stop, 1 stop ... in between. With 10FPS like on the 7DII, click & voila ! It is all about the same picture and then you select the perfect one once zoomed in x10 or once back home on your gigantic screen ...
2) "DoF indication as overlay" : on 7DII you can overlay some stuff on the screen ... i would propose similar feature if transmission possible to the body and calculation done inside : on the lens i see the focal distance => could it be reported to the body and then DoF calculated like on the apps, and then displayed on the screen ? (in stills macro for example i can do depth measurement, then open apps on smartphone, and calculate/adjust DoF ... but lengthy and not practical ...)

Your thoughts ? Is it plain stupid because there are already ways to do something similar (combination of DoF preview button and change of focusing screen ?) ? Or would that be useful to any of you ?
In that case, do you think it could take place as a normal in-body feature in a distant future on some special stuff like say magic lantern ...

Thanks for your feedbacks!

 

[Zeidora]

You will need a different focusing screen to see dof with preview button. Don't have my camera here but you may be able to do Dof bracketing in Tv mode. Dof is gradual not on/off. The ideal amount is a question of taste and also depends on enlargement of final image. I suggest to experiment on tripod in controlled conditions then learn what works under which circumstances.

I learned that what I like on focusing screen or live view requires +1 stop for final 8x10 to 13x19 print.

Alternatively. Stop down too much and do blur masking in post. But there goes your lens bouquet

If you want steep sharp soft transition you can do z-stacking of stationsry objects.

 

[FTb-n]

Bracketing in Tv mode with a static ISO will give you three different f-stops, but at three different exposure levels. In Auto ISO, the f-stop remains static and the ISO changes.

I often shoot team photos with 2-3 rows of players and using the 70-200 f2.8. Typically, I shoot at 5.6 to 6.3, but I'm guessing at DOF. Results have been good, so I rely most on practice and experience.

Bracketing for DOF with constant exposure is an interesting idea. But, I'm not much of a fan of auto-bracketing. When I bracket, I do so manually and I have manually bracketed aperture for DOF.

However, I really like the idea of in-camera DOF calculation. I would like to see a DOF display option where the camera takes the aperture, focal length, and focus distance, then returns the estimated DOF in feet and inches. The user would need estimate what is in focus based on the selected focus point with a third of reported DOF in front and two-thirds behind it.

Canon, are you getting this??

 

[dak723]

I like your idea of DOF bracketing! I shoot a lot of flower pics and do a manual version of bracketing. I will usually take 3 or 4 pics as I change from one aperture to the next. Probably takes about at least a second or two between shots, so works OK, but could be better if the camera did it automatically. I have found that DOF preview has never been particularly helpful in any camera I have used over 35 years! What looks in focus through the small viewfinder or back screen isn't always in focus when seen on the computer screen or print. So I always "bracket."

 

[RunAndGun]

Some older film bodies did have a depth-of-field auto exposure shooting mode. I've never used it, or delved much into it, but my EOS-3 has it.

 

[Valvebounce]

Hi RunAndGun.
I think you are thinking of A-DEP, this worked to make sure you had the aperture to cover the dof you required. You had to focus on the near point, then the far point and the camera would select an aperture to suit, I tried it out on my 1000FN, it worked quite well up to a point, I don't recall the camera bothering if it put the shutter speed waaay to low for hand holding, and of course we couldn't just bump the ISO up to 1600 or 3200 or more on better bodies like we can today! ;D

Cheers, Graham.

Some older film bodies did have a depth-of-field auto exposure shooting mode. I've never used it, or delved much into it, but my EOS-3 has it.