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Canon 24-105 woes

Eric Santiago

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I wasnt sure where to place this post but Ill try here.
I have an older Canon 24-105 for testing with my Scarlet.
I also have a Tokina 11-16 and Rokinon Cine 35/85.

My question is, why am I struggling with the image on the Canon?
Focusing outdoor with this lens is a PITA.
I can accept inexperience as far as lighting and set-up but testing this in broad daylight has been brutal for me.
Recent conditions outdoor is -35 windchill :P

Im using an LCD only for field and doing my best focusing.
Used a .9 ND for the tests at 6:1 4K@23.976.
The lens is maxed at F22.6 during tests.
 
The lens is maxed at F22.6 during tests.

F/22 will encroaches on diffraction and will soften your image with this lens.

Try f/8-f/11.

Also, check your back focus. Mega important for zooms.
 
F/22 will encroaches on diffraction and will soften your image with this lens.

Try f/8-f/11.

Also, check your back focus. Mega important for zooms.


Thanks Phil (to the rescue as usual) ;)

Todays test would not have allowed me that stop setting.

But since you mentioned it I will try again tomorrow.

With the ND right?

No experience with Back Focus yet (as in I wouldnt know how to check).

Edit: found this link on checking back focus.

Thanks again Phil :)
 
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Sunny 16 suggests that 800 ISO at 1/800 would yield f16 in broad daylight. Three stops of nd would bring you down to 1/100. Close up one stop to f22 and you can extend your shutter to 1/50. Given that you are likely shooting with tons of white snow around it looks like it might not be that crazy. In winter around here I often shoot with a 1.5 nd/IR and keep a .6 with me in case I want to open up any more.
 
Sunny 16 suggests that 800 ISO at 1/800 would yield f16 in broad daylight. Three stops of nd would bring you down to 1/100. Close up one stop to f22 and you can extend your shutter to 1/50. Given that you are likely shooting with tons of white snow around it looks like it might not be that crazy. In winter around here I often shoot with a 1.5 nd/IR and keep a .6 with me in case I want to open up any more.


Thanks James, if anyone knows my weather conditions its you ;)
I have to pick your brains a bit more on this type of shooting, although its not something I plan to do all the time (-40wc) :P
I only had a .9 FORMAT with me at the time I take it that wasn't enough if I wanted to use f/8 as Phil suggested.
My shutter doesn't move much due me mostly shooting at 23.976 unless I'm using the 1K@120fps mode.
I will give it one more try today in this frigid day.
 
I shoot a lot in snow and freezing conditions and have used the 24-105 to some extent. I primary shoot action sports in those conditions so I use a higher shutter speed to control the light (and ND).

mostly I use the Red zoom 17-50mm and find that a bit better than the 24-105, but have got good results with both. I usually stay around 5.6-8.

Edit: I just saw that you use a Scarlet, I have an Epic and do a lot of slowmo and that always helps of course
 
I shoot a lot in snow and freezing conditions and have used the 24-105 to some extent. I primary shoot action sports in those conditions so I use a higher shutter speed to control the light (and ND).

mostly I use the Red zoom 17-50mm and find that a bit better than the 24-105, but have got good results with both. I usually stay around 5.6-8.

Edit: I just saw that you use a Scarlet, I have an Epic and do a lot of slowmo and that always helps of course


Thanks Joachin.
Currently just testing the basics of this lens.
No CU subjects just city scapes etc...
Do you switch mounts on the fly during shoots with the RED and Canon during shoots?
 
R1 resolution is nowhere near the refraction limits on a modern lens. I suggest you check the lens on a Canon camera and then check the flange depth (camera mount) if the lens looks fine on the Canon
 
i use the 24-105 all the time and have no problems....i agree strongly with the lower f stops...maybe your ND is the problem? especially when shooting at f22...
check your back focus as well, although it should not be that big of an issue....since the lens starts at f4....but definitley check....
i don't know how anyone can focus without the LCD finder a reduser member from brazil is selling here....
 
Eric def shoot at a lower F-Stop (f8 or f11 as others have suggested). Most stills lenses max out at btw 5.6 and f11.

Also, what's your shutter at BTW?

I guess throw on more ND to stop down (just watch out for IR pollution). Use some IR ND (or a hot mirror) if you're going to add more than .9

Good luck!
 
...Most stills lenses max out at btw 5.6 and f11...

For stills yeah..stopping down will give you sharper picture in the corners and midframe area.
But for motion seems like the center area sharpness is best between f/4-f/5.6 and then hopefully
the corners will blow out in an interesting looking way.

With this Canon 24-105 seems f/5.6 looks pretty good.
Here is f/5.6 compared to f/16

http://www.the-digital-picture.com/...meraComp=453&SampleComp=0&FLIComp=0&APIComp=2
 
thanks everyone for the great tips.
I got further ahead with the Canon using higher shutter speeds.
Im still scared of the whole backfocus adjustment but since this lens isnt mine I figured Ill wait for a better lens.
is it safe to say that most PL lenses exceed all lower end EF offerings.
after experiencing the PL on our RED MX at work, Im having a hard time matching or better with my lense set and Scarlet.
Im pretty sure its due to inexperience.
 
I want to say thanks again for everyone's contribution to this post.

With all the tips I managed to have a decent time with lens.

It will take some time for me to get used to this craft, its unlike anything I do in a day to day basis :)
 
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