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-   -   VX2100 with Raynox Telex & Butterfly Hood (https://www.dvinfo.net/forum/sony-vx2100-pd170-pdx10-companion/99111-vx2100-raynox-telex-butterfly-hood.html)

J. Stephen McDonald July 17th, 2007 02:17 AM

VX2100 with Raynox Telex & Butterfly Hood
 
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Below is a picture of my VX2100, with a Raynox 2.2X telextender and my new BSP-H81 butterfly hood. The lobed contours of this type of hood are intended to prevent vignetting that a standard hood might cause. When a round lens throws an image onto a rectangular sensor, the corners are most likely to show vignetting and the hood has its shortest parts at those points.
Sometimes, a hood will cause vignetting when mounted on a telextender, even though it doesn't do this when put directly on a camcorder's basic lens.

Perhaps these butterfly or "flower" hoods will become more available for all sorts of cameras that have long lenses. They are used extensively on D-SLR cameras and Sony included them this year with its DSC-H7 and H9 digital ultrazoom cameras.

The other picture shows what I used for the fiberglass molding forms for the two hoods I recently made. I ate the non-fat sour cream and gave the ricotta to the very appreciative neighborhood cats. The Frigo carton was the only thing I could find, that exactly fit the 81.2 cm. inside diameter of the outer barrel of the Raynox lens. These hoods slip over the outside of the telex housings, so no mounting threads or matches with them are required.

The other telex is a Sony VCL-DH1758. I use both of them on digital still cameras and the Raynox also works on all my camcorders. My next butterfly hood will be for the Sony VCL-HG1758 1.7X telex, that is specialized for the VX2100 group of camcorders. That is, if I can find a 92.5 cm. flared carton for it.

Marco Wagner July 17th, 2007 09:38 AM

VERY nice, i want one!!! How much?

J. Stephen McDonald July 17th, 2007 06:44 PM

Here's the Instructions
 
Quote:

Originally Posted by Marco Wagner (Post 713269)
VERY nice, i want one!!! How much?

Marco, I'd like to be able to supply these hoods to people, along with my shoulder-mounts and the other gear I make. But, the only business I'm in, is to avoid work whenever possible (this seems not to be possible, a lot of the time). I have included a link to a thread I posted yesterday on another forum group, that gives instructions for making these hoods as a DIY project. Go to the beginning of that thread and see other remarks that I previously made about the hoods. If you go to my Flickr photo album, that has a link to it on that message, you can see many digital still pictures I took using the Raynox telex, some of them done with the VX2100 as J-PEGs.

In addition to what is said there, I use 4 layers of 7.5 oz. fiberglass cloth and polyester resin for them. Working with fiberglass on a project like this is not easy, if you don't have some experience and basic knowledge of how the material is used. There are some hazards in using it, that I describe on that message.

Today, I'm making a butterfly hood for a Sony VCL-HG1758 telextender, which is made specially for the VX2100 series of camcorders or most others that have similar mounting threads. This telex is more versatile and practical for use on these camcorders, than the Raynox DCR-2020PRO. The Raynox telex will vignette below 88% full zoom on a VX2100, but the Sony vignettes only below about 44% full zoom. The Raynox 2020PRO will vignette throughout the entire zoom range on HDV camcorders that have 72mm mounting threads. Raynox makes another expensive telextender model just for the larger-sized HDV camcorders and you might check it out on their website (it is really big). Due to the simpler contours of the HG1758 at the outer end of its housing, it is an easier project than dealing with the curved end of the Raynox telex. I will post pictures of it when it is finished in a few days.

http://forums.dpreview.com/forums/re...ssage=24027052

J. Stephen McDonald July 17th, 2007 10:08 PM

I Found a Matching Carton for the HG1758
 
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I have had more luck in finding a carton that has the right size to fit the Sony VCL-HG1758 telextender, as a fiberglass molding form for a butterfly hood. Here's a picture of it on the telex, ready for the fiberglass:

Marco Wagner July 18th, 2007 01:14 PM

Thanks a bunch, this seems like a fun project.

J. Stephen McDonald July 18th, 2007 08:45 PM

Photo Showing Pattern Markup for Hood
 
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This picture shows the hood and carton with the fiberglass applied and cured and the margin trimmed off at the bottom end. I have marked up the pattern lines to cut out the lobes with a sabresaw and a narrow, fine-toothed metal-cutting blade. You can see how I marked the four sectors. I drew straight lines between the high and low points of the lobes with a ruler and then drew the curves outside of them freehanded. The long lobes are .6 cm. wider than the narrow lobes. The overall length of the hood is 11 cm., with 2.5 cm. that laps over the outside of the telextender's barrel, for mounting. The long lobes are 3 cm. longer than the short lobes and the short ones extend 2.5 cm. beyond the shortest point in the gaps between them. The gaps start 3 cm. out from where the telex barrel ends. A flexible fabric-measuring tape is helpful in this process. This hood is longer than most commercially-made ones, but I think that its contours will prevent any added vignetting. If any vignetting does occur, beyond what the telextender itself would cause, then I'll re-cut the lobes and gaps shorter.

I have been directed to a commercial source of an 82mm flower hood. It is made of plastic and has threads that apparently would match those at the end of the Raynox DCR-2020PRO telextender. The company is called Photo-xpo and it operates on eBay. They also have 52mm and 58mm flower hoods, but bear in mind that these sizes are for the threads on which they would be directly mounted. If a camera with a 58mm filter thread size was using a telextender, the outer barrel threads of the added lens (if any) would be larger. Here's the URL:

http://cgi.ebay.com/82-mm-82mm-New-f...QQcmdZViewItem

J. Stephen McDonald July 21st, 2007 04:32 AM

Butterfly Hood Finished for VCL-HG1758
 
2 Attachment(s)
This is butterfly hood BSP-H98, with the Sony 1.7X telextender VCL-HG1758.
It's mounted on a VX2100. Note: Since I took these pictures, I've cut 18 mm. of length off the base of the hood. It's now 82 mm. long, with 67 mm. extending beyond the telextender. It is 98 mm. in diameter at its mounting base and flares out to 103 mm. at the outer end.

Tom Hardwick July 22nd, 2007 01:26 AM

Excellent work Steve. I've always maintained that a lens hood is the cheapest and lightest accessory you can buy and use that brings with it the greatest returns in picture quality. Well done.

The best hoods are aspect ratio shadowed hoods (as supplied with the original VX2000) but the petal hood is the next best thing. The VX2100's hood (as well as the FX1's) lost the shadow because of the inclusion of the lens capping barn door mechanism.

tom.

J. Stephen McDonald July 22nd, 2007 02:41 AM

1 Attachment(s)
Quote:

Originally Posted by Tom Hardwick (Post 716505)
Excellent work Steve. I've always maintained that a lens hood is the cheapest and lightest accessory you can buy and use that brings with it the greatest returns in picture quality. Well done.

The best hoods are aspect ratio shadowed hoods (as supplied with the original VX2000) but the petal hood is the next best thing. The VX2100's hood (as well as the FX1's) lost the shadow because of the inclusion of the lens capping barn door mechanism.

Thank you, Tom. Here is a picture of the whole lineup of 4 butterfly (petal? flower?) hoods I've made in the last week. The two on the right are with a Sony DH1758 digital camera telextender and a Lensmate 58mm lens adaptor for a Canon S5 IS camera. Since making and testing them, I have shortened the 3 largest ones by varying amounts from 1 to 2 cm. They were a bit too long and raised the point that vignetting started in the zoom range, by a small amount. Since one of the objects of them is to avoid added vignetting, this had to be corrected. Nothing like hands-on observation and evaluation to learn something.

I assume that by "aspect ratio shadowed hood", you mean one that is rectangular and 4:3 in aspect. Could you describe the details about how they work?

Tom Hardwick July 22nd, 2007 02:55 AM

A hood should always match the aspect ratio of the format you're working in Steve. Your petal (flower?) hoods do just that of course, with your cutouts accurately matching the corners of the frame. The Z1's underscan mode is a real boon here, and tells you of impending vignetting.

If you get hold of a VX2000's supplied hood you'll notice at the front of the hood there's a 4:3 aspect ratio rectangular mask. The beauty of this is that it means a lot of the interior of the hood is in deep shadow - even when you're out shooting in sunlight. And as you know - even matt black paint reflects quite a bit of light when directly in the sun.

Sony didn't do this for fun, and the complex multi-part construction goes a long way to showing how much more professionally they approach the matter of flare over Canon, say, with their XL1s and XM2.

Now look at the stock hood that came with your VX2k1. The lens-cap barn-doors mechanism effectively rob the hood of its excellent shadow mask. To compound the felony, the hood supplied with my FX1 and Z1 not only lose the shadow mask, but the barn doors are shiney black, accurately positioned (when open) to reflect sunlight right into my front element. Very poor, Sony.

I note that the FX7 / V1 hood has corrected this somewhat with a much more matt black barn door.

As always, a hood is only an efficient hood at maximum wide-angle of the zoom lens. At all other focal lengths (all of them) the hood is inefficient, and at max telephoto is at its least efficient. And if you use your VX2k1 in the 16:9 mode, then the hood is even less effective of course, right throughout the zoom range.

Which is why I like to see dedicated hoods such as yours. There's no real substitute.

tom.

J. Stephen McDonald July 22nd, 2007 03:59 AM

Thanks again, Tom. You've set me onto my next project-----to make a 4:3 shadow-mask hood for my VX2100 for when I'm shooting without a telextender. Do you think the VX2000 hood is the ideal version of this type to study, when I work out the design? Could the hood or the opening be larger or smaller for a better effect? I may work out a way to use the bayonet mount for it. I might even consider sacrificing my "barn-door" hood for this part of the fixture.

And I thought I was through fussing with gadget-building for awhile and ready to just do some shooting. Now, I'll also have to make a butterfly hood for the VX2100 for use without a telextender.

Tom Hardwick July 22nd, 2007 08:45 AM

No need to make a shadow mask hood for your VX2k1, just get hold of the VX2k's version. They're availanle from Sony spares, and I bought one to butcher so that I could bayionet on my wide-angle converter.

The VX2k version doesn't have the silly barn doors compromising its hooding efficiency, a big plus in my book. But it has rather too large an aperture - the mask needs to *just* not vignette the entire frame (visible on your computer) then it's as efficient as it's ever going to be.

But if you're going on safari, say, and only using focal lengths in the range of 50 - 72 mm then all you need to do is stick on shadow masks that have smaller apertures Tiny pieces of velcro on the existing mask and on your 'alernative telephoto masks' (clearly identified with the focal length at which they begin to vignette the image) will be just as efficient as any other hood you design, and probably a lot more convienient.

tom.

J. Stephen McDonald July 25th, 2007 03:49 AM

Another Hood for the VX2100
 
1 Attachment(s)
The butterfly hood shown below is made for use directly on the basic lens, without a telextender. It isn't very large, but it is as big as it needs to be. The side lobes and the gaps between are cut shorter than I made them at first. It was causing a bit of vignetting at the full wide position, so I carved it down, so it just barely doesn't vignette. With a telextender, that causes its own vignetting, these hoods can have longer side lobes and smaller gaps. Since the wide angle below about 44% full zoom is lost to telextender vignetting, with the HG1758 telex for example, the hoods can stick out farther on the sides and corners.

This is a screw-in hood. I knocked the glass out of an extra 58mm UV filter and used epoxy glue to attach the fiberglass around that. Since the hood doesn't rotate on the mounting rim, I had to align the lobes to exactly match the position it would have when tightly screwed onto the lens.

I've discovered something else for the hoods that may make them more effective. It's Ultra-Flat Camouflage Paint, by the Krylon Co. I used some of their ultra-flat black on this one and compared to standard flat-black, it really is much less reflective. It would be most important to use it on the inside of the hoods. I may carefully paint the insides of those barn-doors on my stock VX2100 shadow-mask hood with it. Then, I'll see if I can detect a difference in any glare that might reflect off them when they're in the open position.

Tom Hardwick July 25th, 2007 09:30 AM

That painting with camouflage paint sounds a good idea Steve. You might have to roughen up the surface of the barn door to get the paint to key well, as you don't want tiny bits flaking off when you snap those doors shut.

The reason I haven't applied self-adhesive black flock to mine is for this reason - tiny individual hairs on the flocking let go every now and again, and sure enough they'll end up on my front element. At the focal lengths we're using, that's a real no-no.

tom.


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