Threads
Is there a way to lock focus ring?
- By Perio
- Canon Lenses
- 4 Replies
Hi guys, I hope you're doing fine. Maybe I have a naive question but it may help me a lot in my daily clinical practice. I use Canon 100L macro lens to take pictures of my patients in the clinic, and sometimes I wrap the camera in a sterile plastic bag during surgeries. Often while I'd wrapping the camera, the focus ring gets displaced, and then it's a pain to adjust it. The question I have is if there is a way somehow to lock the manual focus ring, so it always stays at the same level? The reason I need it to always stay at the level is to always have the same distance to an object, and when I crop the teeth/tissue is the same size. Thanks in advance! 
DIY weather sealing--silicone wrist band?
- By YuengLinger
- Canon Lenses
- 4 Replies
Got the idea from using a Lens Band for my droopy ef 24-105mm. The Lens Band keeps the zoom barrel from sliding down while walking.
Would adding a silicone wrist band (which is all the Lens Band really is) to the mount area for, say, a Sigma 50mm Art or some other non-weather sealed lens accomplish ANYTHING towards keeping mist/rain/snow/hail out of the body?
Please don't tell me to go out in the rain and test the idea!
I got a few free wrist bands as a memorial gift from Paul C. Buff with an order earlier this year.
Was hoping to put them to some kind of use.
(If this has been asked and answered, sorry. A search revealed so many hits not on point that I just decided to ask.)
Would adding a silicone wrist band (which is all the Lens Band really is) to the mount area for, say, a Sigma 50mm Art or some other non-weather sealed lens accomplish ANYTHING towards keeping mist/rain/snow/hail out of the body?
Please don't tell me to go out in the rain and test the idea!
I got a few free wrist bands as a memorial gift from Paul C. Buff with an order earlier this year.
Was hoping to put them to some kind of use.(If this has been asked and answered, sorry. A search revealed so many hits not on point that I just decided to ask.)
Does this kind of AF patent already exist to improve DSLR phase detect?
- EOS Bodies
- 0 Replies
Hi,
The A7RII is getting a lot of attention, especially as regards its AF ability. A lot has been said about DSLR phase detect's "moderate" ability to AF on a wide-aperture primes and AF micro-adjustments.
So, I was wondering if a patent such as the following was already reported here or elsewhere: the idea is to primary use the usual dedicated phase detect of the DSLR. Then, when mirror raises a second unit, on-sensor phase detect (Dual Pixel AF for Canon), corrects the slight inaccuracy by asserting good AF rather than predicting it just before taking the shot.
Given the fact that even if the external AF module is not accurate, it is not completely off even at f/1.4. That means the correction to be done by the on-sensor phase AF would rather be minimal, hence meaning NOT THAT MUCH time consuming.
The external AF and on-sensor AF would share the same AF points. So when the mirror raises, the on-sensor AF knows which was the selected AF point and therefore knows where the "correction" has to apply.
BTW, some DSLR already proposes a delay when the mirror raises to wait for mirror vibrations to dampen. So let's use this "idle" time to do what's described above.
The only "risk" would be that the viewfinder remains dark a bit longer. But aren't we already used to it when exposure is slower than say 1/60?
It will also correct from brand to brand variations (like Sigma not focusing as good as Canon lenses on an EOS body)
This would make wonders within the Canon AF dedicated menu where you could set a priority with a slider to the importance you allow to the "correction": from quickest (on-sensor AF deactivated) to not fire the shot until the on-sensor has 100% asserted the accuracy.
What do you think? Any reports of this?
If it doesn't exist yet, my idea first
The A7RII is getting a lot of attention, especially as regards its AF ability. A lot has been said about DSLR phase detect's "moderate" ability to AF on a wide-aperture primes and AF micro-adjustments.
So, I was wondering if a patent such as the following was already reported here or elsewhere: the idea is to primary use the usual dedicated phase detect of the DSLR. Then, when mirror raises a second unit, on-sensor phase detect (Dual Pixel AF for Canon), corrects the slight inaccuracy by asserting good AF rather than predicting it just before taking the shot.
Given the fact that even if the external AF module is not accurate, it is not completely off even at f/1.4. That means the correction to be done by the on-sensor phase AF would rather be minimal, hence meaning NOT THAT MUCH time consuming.
The external AF and on-sensor AF would share the same AF points. So when the mirror raises, the on-sensor AF knows which was the selected AF point and therefore knows where the "correction" has to apply.
BTW, some DSLR already proposes a delay when the mirror raises to wait for mirror vibrations to dampen. So let's use this "idle" time to do what's described above.
The only "risk" would be that the viewfinder remains dark a bit longer. But aren't we already used to it when exposure is slower than say 1/60?
It will also correct from brand to brand variations (like Sigma not focusing as good as Canon lenses on an EOS body)
This would make wonders within the Canon AF dedicated menu where you could set a priority with a slider to the importance you allow to the "correction": from quickest (on-sensor AF deactivated) to not fire the shot until the on-sensor has 100% asserted the accuracy.
What do you think? Any reports of this?
If it doesn't exist yet, my idea first
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