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Canon 8 - 64 & Veiling Glare/Flare


Greetings everyone,

On a current job working amongst other optics with the Canon 8-64 T2.4. On some shots against very bright backgrounds mainly windows and despite flagging out, masking out the optic, we still have a little bit of glare making some contours slightly soft on subjects in the foreground. The optic is also clean, no smudge whatsoever.

The shots work but I am surprised we still have these tiny glare. Could a change of optic be an answer? Could it be just that one Canon? Before calling rental department and ask for another Canon 8-64 wanted to have your opinion.

Appreciate your help, thanks beforehand.

Regards

Emmanuel SUYS
Kamera-Assistent, Focus Puller, Assistant Camera
Français, Nederlands, English, Deutsch


Hi Manny,

I've always found the 8-64 to be a very clean lens, it's one of the reasons that I prefer it to later versions.

I'd check out an alternative if you can.

Cheers

Geoff Boyle FBKS

Director of Photography
EU based
www.cinematography.net


>I've always found the 8-64 to be a very clean lens, it's one of the reasons >that I prefer it to later versions.

I'm using one now too, but if its real bright it could veil on you. It’s not near the antiflare quality of the newer HD 21x & 11x, but its still a solid lens that doesn't focus-breathe.

You might be able to find a better one, but it would be mostly in the coatings, right ?

Mark Doering-Powell
LA based DP


Mark Doering-Powell wrote :

>You might be able to find a better one, but it would be mostly in the >coatings, right?

Greetings,

Well, I would guess the difference is mainly due to coatings. Maybe the coating is not as it used to be due to age and improper cleaning technique.

Used the Canon 8-64 quite a lot before and as a matter of fact in the same location but in different lighting set-up. Never had such a nasty little bugger.

In the event I cannot get an alternative, as rental facility is almost totally empty (everyone is rolling right now), would the Canon 7-63 be as effective glare wise?

Presumably I would have to test but time is lacking on my side as very heavy schedule.

Regards

Emmanuel SUYS
Kamera-Assistent, Focus Puller, Assistant Camera
Français, Nederlands, English, Deutsch


If you have a very bright, blown out window and place a subject in front of it, the Canon 8-64 will always give a little bit of veiling around that subject. I have found that you need a pretty bright window to make that happen, but it is an artefact I've seen repeated on numerous 8-64s, including my own. The same is true for other Canon zooms such as the 7-63, 11.5-138 & 11.5-165.

I consider it a very minor flaw in an otherwise excellent lens set. Also be sure to have a decent mattebox or sunshade. Light hitting the front element at an acute angle can cause a green flare that you might not pick up until dailies.

Mitch Gross
NYC DP


>the Canon 8-64 T2.4. On some shots against very bright >backgrounds…still have a little bit of glare

I worked with the Canon 8-64 on an action TV series and we found that we had to limit bright skies in the back ground or we would get a veiling flair (not attractive). Not blown out skies at open stops as our day/ext stops were 5.6 or deeper, set ups you wouldn't worry about in 35mm. It was a surprise the first time we saw this in video dailies but there is a hint of the flair in the viewfinder if you look carefully (even the SR III finder). Any way we often set shots from higher angles or moved set dressing/greens to limit patches of sky in the frame.

David Campbell
Steadicam/op


Mitch Gross wrote :

>Also be sure to have a decent mattebox or sunshade. Light hitting the >front element at an acute angle can cause a green flare that you might >not pick up until dailies.

Greetings Mitch,

MB-16, Masks or Mattes, Eyebrow and sides even showing up in the safety, even Black-Wrap closing between sides just above the rods when light bouncing from reflector, French flag. Using all techniques I know of. The gaffer and his boys are also doing a great job. Flags are always positioned to cut off direct light hitting camera.

Shooting wide open no filter. Guess this looks like maybe a coating difference. I'll have a close look at the optics on Monday morning. Have a chat with the rental dept. to see if I can have a second one send and compare both.

Or maybe I am just to picky.

Regards

Emmanuel SUYS
Kamera-Assistent, Focus Puller, Assistant Camera
Français, Nederland’s, English, Deutsch


David Campbell wrote :

>Any way we often set shots from higher angles

Greetings David,

That is exactly what was done the next day I saw the dailies. On one particular set-up suggested the DoP to frame from a higher angle as I was almost convinced that whatever we did to block off we were going to get veiling glare. It was quickly done as a safety just in case it would look to soft. Awaiting to see the dailies on that.

Regards

Emmanuel SUYS
Kamera-Assistent, Focus Puller, Assistant Camera
35mm - 16mm
Français, Nederland’s, English, Deutsch


Emmanuel,

When working on these lenses, its not uncommon to find a light blue haze on the surface of the internal lens elements. I don't know if it is the white Canon grease "outgassing" or whatever. I've had to completely clean the glass in several of these zooms. If you get a chance, put the zoom on a lens projector and look down it, you will be able to spot the haze easily.

Regards

Andy Taylor
Camera ( and lens! )Engineer
Arri Media
3 Highbridge
Oxford Road
Uxbridge
Middlesex UB8 1LX
UK
www.arrimedia.com
www.arri.com


Greetings everyone,

Just to inform that all glare problems are gone and well gone. Changed the lens and what a difference. Back to standard masking and flagging procedure and no more alternative angles. Was a very frustrating moment.

The lens technician at the rental place could not see a difference on his testing bench either. He was going to go for a test with shooting some neg as well.

Thanks for all help

Regards

Emmanuel SUYS
Kamera-Assistent, Focus Puller, Assistant Camera
35mm - 16mm
Français, Nederland’s, English, Deutsch



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