Teleconverters

[Dale Guthormsen]

Brendan,

I did all the post in elements, I only cut out the audio and put the title overlays on a seperate tracks.

I shot from approximately 75 feet, all from the same spot.

As you zoom in on an object the lens does not collect as much light. this requires opening up the aperature and the amount you open it will definitely make a difference in brightness. If i recall I left the aperature at f22 until I got to 500mm but perhaps I changed it at 350 taking it down two clicks which makes it f 16.

I focused best i could but to be honest I think I need a fu 1000 to get better focus on the longer reaches.

Oh yea, I have the camera on cine with technacolor presets and a little extra red.

Curiously, do you like the color as I have it set?

[Brendan Marnell]

Until you posed the question "Do you like the colour as I have it set" I hadn't asked it of myself. That's partly because I'm trying to learn about videoing & post & putting stuff on view;

... as a longtime gardener I grow and enjoy & photograph a fair range of plants and flowers & I am automatically sceptical about the universal habit of "enhancement" when colours in nature appear in the media (It fits into the same slot in my tiny mind as "the worse the melody and harmony the louder we have to play the beat & shriek the words" + turn up the volume anyway to convince ourselves & the neighbours we mean it). In short I didn't expect to believe the colours so I didn't even notice them ... but now that you ask ... I find them all to be too warm, too saturated and therefore unreal ... I do realise that the alternative was to show them washed out as in nature where the foliage absorbs sunlight in ways our eyes (& our skins) can't cope ...

[Dale Guthormsen]

Brendan,

The colors are slightly oversaturated as you mentioned. If you are looking on a computer monitor the colors are almost always brighter, more vivid and richer than when you see them on a large screen tv!!! I played it on my 54 inch and they look realistic.
when I make a dvd I color correct so it is as close to reality as possible. Things are very bright here in the prairies, this always means color correcting in post.

[Brendan Marnell]

That makes good sense Dale, thank you.

I've just got Premiere Elements to send me an audio email (birdsong), now I must learn to send a video and then who knows I'll learn to follow your example and post a few snippets for snipers ...

[Sam Mendolia]

My 2 cents.

Hello all, I'm new here, so forgive me for being late on this post.

I purchased a Raynox DCR1.85x Pro, a couple of years ago, for my Minolta still camera.

Works great on that unit, with a step up ring 49-52mm?

Slight vignette, and minor CA, depending on lighting.

I tried it this past weekend, on my Optura.

I had to zoom to just past the 50% mark, and the vignette was not visible in the viewfinder.
Zoom to full out, and depending on lighting conditions, CA was noticable, and the image was soft. Pulkl back, and the CA and softness were gone and the image was sharp.

Looking at in on the NLE system at work, and the images looked sharp, when I was not moving the camera, mounted on the monopod. Gotta use the tripod from now on.

The vignetting that was not there in the viewfinder, does creep in, on the NLE screen, so gotta watch for that.

The CA, again, depending on light and zoom range, is there.

Has anybody played with a ND filter or Polarizer, between the lens and Teleconverter, to try and minimize the CA?

That's my 2cents worth.

Hope to post more, as you have been a wealth of info, for me.
I now know where to go, to give me inspiration, and may get 14years worth of footage edited and critiqued.

I may even try my hand on a challenge.

Thanks.

[Tom Hardwick]

Originally Posted by Sam Mendolia

Has anybody played with a ND filter or Polarizer, between the lens and Teleconverter, to try and minimize the CA?

Best not to put anything between your zoom's front element and the telephoto converter, as anything you place there will add to the vignetting and rob you of some sharpness.

Sony (PD170, VX2100) and Canon (XM2) used to put their OIS elements ahead of the zoom's front element, but they too have seen the light.

tom.

[Sam Mendolia]

Thanks for the reply Tom.

I had thought about the extra vignetting, and my thinking led me down the lane of "thin" filters, to reduce the vignetting.

So the scenario would be, camera, filter, teleconverter.

I will test this out, and see how much sharpness I lose, and if I can can control some of the CA. I know that I will have to zoom farther, to get rid of the vignette, I have at present.

I'm just tinkering, for the sake of tinkering, when I can't get out and actually shoot.

This week will be a lot of tinkering, a lot of rain here this week, the weekend looks promising, so maybe my tinkering will pay off.

[Dale Guthormsen]

sam,\

This is always interesting stuff!!

What would be the point of placing filters between the camera and duplex? Perhaps you just do not have the larger filters for the outer lens.

If this is the case, I have quite a few different sized lenses for both of my cameras, so I solved that problem by buying a conkin 3x3 filter holder and hood that adapts to lenses sized from 48 to like 86 mm. Any filters I purchase i get in 3x3 size and i can use them on anything. I believe it is the P system. It is also economical.

Look forward to your grabs/clips and comparisons.

[Sam Mendolia]

Thanks for the input Dale.

Actually, the Raynox thread is larger than the Canon.

My thought was to find a way to reduce the CA, with some "other glass".

Yes, the "other glass" will produce it own degradation, in some form, probably a softer image, but that would be okay, as the "look" I'm after at the moment will be fine with that.

My nature videos will not look sharp, but then again, it is still dependant on what feel I am trying to acheive.

If I can not get the look I want, it does not get screwed onto the front of the camera lens.

This Raynox lens does not have a front thread, so we can forget about trying that.
I can build a mount for the front, of the Raynox, and screw it down, much like the GL2 lens hood, and then use filters there, and hopefully not introduce more vignetting.

I have a large collection of film filters, that could go in front of the lens(es), from my old still photo days. That would take alot of trial and error, that is why I 'm here, to learn from all of you, but... still make my own mistakes, and learn from them. Hands on, thats me.

I still haven't been able to test, as the kids, the wife, and the gardening between the rain, are taking up a lot of time. They aren't the best guinea pigs, they move to fast for me, when I'm trying to think. I am trying new things, that are new to me at least.
Right now the back garden is the small world I will be working in, so I can test, and re-test, much quicker. Then I can take it out on the road, and see how it handles.

As my wife says, I think too much.

But, when I'm done thinking, I get really good results, that I can repeat.

Keep you posted.

[Sam Mendolia]

I will have to test this Raynox on my old Sony, that has a really small lens, and see what results I get.

The lcd should show me whether or not the CA is worse, and make Dale's point hit home.

But then again, I am stubborn, and will keep trying with the Canon as well.

[Sam Mendolia]

Well I didn't test it on the Sony, but I did test it on the Canon again.

Finally got five minutes to my, on a day off work, and the weather cooperated.

Conditions were similar to my first use of the Raynox on the Canon.

I took of the UV filter, and screwed on the Raynox.

The image was sharp, and the chromatic abberation was almost non-existant.

Zooming in quickly, showed some CA, but once the image focused it was gone, right out to my max zoom.

I guess I will have to take off the UV filter whenever I plan to use the Raynox.
Next test is to try the circular Polarizer, just for those situations, that call for it, like when I'm out by the water filming fish and turtles, or images with glass reflections.

But as Dale said, why put something between the lens and the converter?

I'll have to find out of the Polarizer is one of those things that will be of use, without causing other unwanted issues.

For now though, no UV filter while using the teleconverter.
Haven't tried the wide angle converter yet.

But that will be another story....

[Tom Hardwick]

Originally Posted by Sam Mendolia

For now though, no UV filter while using the teleconverter.
Haven't tried the wide angle converter yet.
But that will be another story....

It's even more important to remove any filters when you use a wide-angle converter, primarily because of the very short focal lengths involved. Of course there may well be specific instances where your polarisor will be required, but do make tests first to chek for vignetting and flare.

tom.

[Brendan Marnell]

Originally Posted by Tom Hardwick

It's even more important to remove any filters when you use a wide-angle converter, primarily because of the very short focal lengths involved. Of course there may well be specific instances where your polarisor will be required, but do make tests first to chek for vignetting and flare.

tom.

Tom, please tell me: Is a camcorder (say XL2 + x 20 standard lens) made to perform at its best without any filter or polarizer? ... assuming that the visibility is good outdoors.
In other words, should the optimum be to take off filters if weather conditions are favourable and the glass is safe?

[Tom Hardwick]

A resounding yes to your question. If Canon or Sony or JVC thought that adding an extra element to the lens line-up would in any way improve the performance, it would be there. The 15 elements in your typical zoom lens all work in harmony and at the price give you the best on offer. Each extra piece of glass or plastic (many of the aspherical elements are high pressure injection mouldings) adds the risk of de-centering and certainly adds flare.

tom.

[Brendan Marnell]

Originally Posted by Tom Hardwick

A resounding yes to your question. If Canon or Sony or JVC thought that adding an extra element to the lens line-up would in any way improve the performance, it would be there. The 15 elements in your typical zoom lens all work in harmony and at the price give you the best on offer. Each extra piece of glass or plastic (many of the aspherical elements are high pressure injection mouldings) adds the risk of de-centering and certainly adds flare.

tom.

That is good news Tom, thank you. The more some accessory is discussed in isolation the more I fall into the trap of thinking that the accessory is more necessary/important than the basic equipment to which it may be attached. I should know in my late 60's that hype is the enemy of truth.

And apologies for a clumsy phrase in my question ".. should the optimum be ..." when I should have written " .. is it best ..."