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-   -   converters, matte boxes and such (https://www.dvinfo.net/forum/canon-xl1s-xl1-watchdog/2809-converters-matte-boxes-such.html)

Josh Bass July 23rd, 2002 04:03 AM

converters, matte boxes and such
 
Okay, so when I have a wide angle converter attached to my XL1s's lens, I cannot use the lens hood, right? Not with any zoom-through converter out there?

If I buy a matte box, can I put this over the converter? Also, are there UV filters that will fit a converter?

Jeff Donald July 23rd, 2002 05:45 PM

I'm going to try to answer your questions as best i can but there may be some exceptions to what I say. The hood will not fit any adapters that I'm aware of. Some matte boxs will fit, some may need modifications to there mounting hardware. Matte boxes that use rods should not be a problem, but they are more expensive. Most convertors, if any, are not threaded for filters. The light fall off in the corners is right at the limit with most WA adapters and the filter would probably cause vignetting.

Jeff

Josh Bass July 23rd, 2002 10:13 PM

See, that scares me. I really think I ought to have a wide angle converter (not an adapter), but I don't want something I can't protect with a UV filter. . .it gets a scratch on it and that's like four hundred dollars gone!

Charles Papert July 24th, 2002 01:03 AM

Josh:

Adding a full-time filter in front of a lens means that you now have a new surface for light to bounce or scatter in/through, which means that it may add to flares or loss of contrast if light is allowed to hit the surface. That expensive coating on the wide-angle adaptor that is designed to prevent just this is being compromised by an uncoated piece of glass up front.

I know that in the still camera world, the first rule when you get a lens is add a UV filter. I can tell you that in the film world, that rule would be protect your lens but work clean, no filter. When circumstances call for it, such as someone firing blanks at the camera or dusty/wet environments, we will add a clear filter (aka optical flat) to protect the lens.

The reality is that it takes a fair amount to scratch a good lens (or wide angle converter). You've got to give it a damn good scratchin' to leave a mark. I have a wide angle in front of my little "beat-em'-up" DV camera, a dog-eared Sony PC3 that I throw into kit bags without much thought, and that wide angle has gone into my pocket with no protection at times. After 3 years or so, I can give it a good cleaning and its front surface is still pristine.
Now, I don't know what you have planned for your shoots--but unless it's so sketchy that you intend to wrap the camera body in plastic for protection, I wouldn't be too concerned about damaging the wide angle lens.

Ken Tanaka July 24th, 2002 01:15 AM

Funny you should mention that, Charles. Monday I was shooting a scene and found myself being chased around by the videographer's/cinematographer's gnats: lens flares. The lighting was ideal, the camera location/angle was perfect. But, damn, there was a nasty little flare in the upper right portion of the frame. Couldn't flag it off without tossing a bad shadow. Couldn't FlareBust it out without getting the flag in the frame. My solution: remove the UV filter. Voila! Flare gone. Apparently it came from light bouncing between the lens and the filter. But I felt like I was shooting with my zipper down. <g>

Charles Papert July 24th, 2002 01:20 AM

Ahh.

Panavision appears to be the only folks to make a mattebox that incorporates a tilted filter tray, which reflects the flares into oblivion, not down the barrel. Smart cookies, they are.

I should point out that the worst situation to have a filter in front of the lens is when shooting a high contrast situation like car headlights pointed at you (at night, obviously), or candles. You will often see a ghost image of the highlight shifted away from the original image. Solution? Lose the filter or--uh--use the Panavision tilted filter tray...not really a solution here, I guess!

Jeff Donald July 24th, 2002 06:30 AM

There are certainly two sides to this discussion. But I feel that this over whelming need to put a filter on every lens to protect it, is for the most part, perpetuated by camera stores and sales people motivated by the high profits that filters bring. Filters are probably one of the highest profit items in a camera store. Filters that sell for $16 to $20 net out at $2 to $4 cost. Even the better filters like B + W, Heliopan and others, have huge markups.

In the early days, mid 70's and earlier, many of the coatings on lenses were very soft and could be easily damaged by their environment or even repeated cleanings. Hence, a real need for filters. However, modern coatings and multi coatings are very hard and can stand up to quit a bit on abuse. In the early 80's a camera store owner, in Bozeman, MT. used to put out his cigarette on the front surface of lenses to demonstrate how durable they really were. In the last 20 years coatings have changed, they've gotten better.

I have seen filters protect lenses on a few occasions also. But not when most people think. It's when a lens is dropped. It invariably falls front down and hits the ground. If a filter is in place, the ring is bent and the glass usually cracks. Break the glass out and remove the ring and the lens is fine. I've also seen many a lens hit the ground without a filter on and it's not a pretty sight (grown men crying).

Myself, I never leave a filter on a lens. I put a filter on for its intended purpose, then I remove it. I don't believe in using filters for protection, except in situations like Charles describes. I do recommend filters for people who are nervous or uncomfortable about handling their lenses or equipment. Newbies are a prime example. They are unfamilar with their equiment and while changing a lens, they loose their grip and the lens takes a hit. So for many people starting out it may be a wise investment. But there may come a time, when they have progressed in their profession, the filter is no longer required for protection. You may even notice the shots look better without the filter. Filters can cause a lot of unwanted flare and ghost images, as Ken points out.

Jeff

Josh Bass July 24th, 2002 12:06 PM

Really? So I can leave my spankin new manual 16x zoom lens unprotected?

But how about my matte box question, I mean we do want to protect our lens from stray light, correct? So if a lens hood won't fit, you need something that will? Right Right? Am I alone here?

Jeff Donald July 24th, 2002 02:33 PM

I don't use protection filters, I do use a matte box. You've got to follow your gut instincts aboutprotection filters. But I don't use protective filters now or I have in the past 20 years. I've never scratched a lens. I use the Image 2000 matte box that I've customized to use Cokin P series filters, Singh Ray filters and others. I use polarizers, ND, color correction, pro mists, and probably a few more I'm not remembering.

Jeff

Josh Bass July 24th, 2002 03:00 PM

Ok then, what's a decent quality, sanely priced matte box that will accomodate a wide angle converter?

Also. . .besides the flares, do UV filters do anything to diminish image quality?

Charles Papert July 24th, 2002 03:07 PM

A good quality UV filter shouldn't affect image quality other than the ways we mentioned. It is nominally intended to reduce background haze caused by UV emissions, but I'm not sure I've ever seen it do much.

Jeff Donald July 24th, 2002 03:20 PM

Check out the Image 2000 matte box http://www.birnsandsawyer.com/cdva-matteboxesandsunshades-image2000.htm it will accomadate the Century Zoom thru WA adapter (95mm). http://www.centuryoptics.com/products/prodv/xl1/7x_wac/specs.htm The adapter lists for $795. The zoom thru's are more costly. The Image 2000 lists for $495. Century also has some modestly priced matte boxes.

Jeff

Josh Bass July 24th, 2002 05:44 PM

I thought the zoom through converters were normally about 3-400? If I'm gonna spend that much for the combo, might as well buy the wide angle lens! I know I've seen several listed in this price range.

Jeff Donald July 24th, 2002 06:04 PM

If you can live with partial zoom thru (to 8x) Century has their .6x WA adapter. It's $395 list and I think ZGC sells Century. Now the problem becomes the Image 2000 comes with a 95mm ring and the .6x is 90mm. I few pieces of velcro and you'd be set.

Jeff

Josh Bass July 24th, 2002 08:24 PM

Ah. . .so if I want the full 16x zoom through, I'm looking at what. . .1200? with mattebox, that is.


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