Cinematography Mailing List - CML

 

Search

Aaton LTR 54 Video Tap

Gentle camera folk,

So time has come for me to upgrade my somewhat dark Aaton LTR 54 Video Tap. The camera has the original LTR Pellicle in it. I have been looking at the AZ Spectrum Video Tap and it seems like a good combo of value to price. I am a bit troubled by the need for them to replace the condenser lens, but simply from a convenience stand point. So my question simply is.

Does anyone here use this Video Tap? Would you recommend it? Any other
suggestions?

Thank You in Advance
Scott Mumford s.o.c.

Motion Picture Professional
Nashville
www.scottmumford.com



>I have been looking at the AZ Spectrum Video Tap and it seems like a good combo >of value to price.

Hi Scott,

I've got the B&W AZ Spectrum tap. I haven't seen the color version or the flicker free one. I had a good experience dealing with Andrew Zorawski (the AZ in AZ Spectrum).

The big pro is the price. There's nothing else on the market at a comparable price. The other pro for me is that it's not a top handle style so I can still, confidently, do underslung shooting mounted from the handle. The big con is that it's not the clearest or sharpest tap ever designed, but I wasn't particularly interested in spending 150% more to get the extra sparkle.

I had difficulty finding another tap that used the standard Aaton relay optics, other than the old tube camera variety.

Good luck!

Frazer Bradshaw
Director of Photography San Francisco
www.seaworthy-cine.net



Scott,


I researched this a while back for my LTR-54. Have you tried CineAsst in Canada?

Tom McDonnell
DP
New Orleans, La



Other manufacturers who make taps for the old LTR pellicle are Etkon and Van Dieman. These are European companies and as a standard offer feature PAL taps, but I imagine they could make them in NTSC as well.

Mitch Gross
NYC DP



Hi Scott,

As an alternative (what I would do anyway) is to replace the video camera only, leaving the housing and optics in place.

There are plenty of small CMOS with an excellent resolution, autoexp and auto white balance for less than $40.

The most "trouble" would be to adapt the new (smaller) camera in place (1 hour machining the most) but I think is worth it.

This is (again) a personal choice.

Good luck


Regards,


Dan Diaconu
Easy Focused Lens Inc.
http://pictures.care2.com/view/1/868859207/0



>What is CMOS and does anyone have any thoughts on what the brightest tap friendly >video camera might be?

CMOS imagers are made very much like typical silicon chips on the same manufacturing lines.

This is why they are so inexpensive. CCD's (charge coupling devices?) are quite unique in their manufacture and therefore more expensive. Good CCD's are much better than the CMOS imagers. Low light performance especially!!!

CMOS imagers are coming along though. The fact that they are the same as other silicon chips is leading at least one company I know to develop cameras on a single chip (Sensing, analog - digital conversion, processing, encoding etc all on the one device).

Some quality improvements will accompany this integration but how much?

This will lead to better cheap cameras for security, camera phones and web cams but will it ever exceed the quality of good CCD's?

I don't think any of the inexpensive CMOS cameras will make superior video assist and most of them are in small chip sizes 1/3rd or 1/4 and the optics in the Aaton are probably throwing the image to a 2/3" imager. You will have a nice tight shot of the cross hairs unless you do some serious image reduction. With that much image reduction you will gain some light intensity - brightness but flatness, contrast and sharpness will almost certainly suffer. Image inversion is another issue perhaps. Some CCD cameras can make a mirror image to right this but most are not capable of this.

Greg DeFoe
Design Engineer
San Francisco



Dan Diaconu wrote :

>There are plenty of small CMOS with an excellent resolution, autoexp and auto white >balance for less than $40.

What is CMOS and does anyone have any thoughts on what the brightest tapfriendly video camera might be?

For Steadicam its all about brightness. I'll trade as much grain as necessary for a little more brightness? Black and white is fine as I am viewing on a TB6 green screen monitor. I am shooting a lot of music video's often in dimly lit clubs or night exteriors and my 10 year old XC-77 is way to dark.

I'm tired of going into that dark night I need a camera to help me rage against the dying of the light.

Mik Cribben-Steadicam Operator
NYC/Miami--800-235-2713



Dan Diaconu wrote :

>There are plenty of small CMOS with an excellent resolution, autoexp and auto white >balance for less than $40.

They'll flicker though.....

Also, you'll need custom relay optics, if my memory serves me well, the image straight from the LTR 54 body is mirrored left/right. Easy to correct on a tube camera, but bloody impossible on a CCD....

It's gonna cost

Andy Taylor
Camera Engineer
Arri Media
3 Highbridge
Oxford Road
Uxbridge
Middlesex UB8 1LX
UK

www.arrimedia.com
www.arri.com



CMOS complementary metal-oxide semiconductor

Regards,
Dan Diaconu



Andrew Taylor wrote :

>Also, you'll need custom relay optics, if my memory serves me well, the image >straight from the LTR 54 body is mirrored left/right.

Ah, no.

The biggest problem you will have is that the image coming out of the Aaton isn't horizontal, it is tilted. Which is annoying. As for the other - Marshall electronics makes a small board camera with switching left right capabilities for about $150 (I think), it is the 1208.

I use it in the Video tap I made.

Steven Gladstone
Cinematographer - Gladstone Films
Cinematography Mailing List - East Coast List Administrator
Better off Broadcast (B.O.B.)
New York, U.S.A.



oops…

>Also, you'll need custom relay optics, if my memory serves me well,

>Ah, no.

>The biggest problem you will have is that the image coming out of the Aaton isn't >horizontal, it is tilted.


So much for my memory…

>Marshall electronics makes a small board camera

Sounds useful, do they have a website?

Got to go, matron is doing her rounds...

Andy Taylor
Amnesiac
Uxbridge home for senile and deranged engineers



Before I bought my tap from AZ Spectrum, I spent a fair amount of money on stuff from the Edmond Scientific Industrial Optics catalogue and a fair amount of time on the phone with their tech support folks.

I failed to be able to make a functional tap, but I learned a thing or two about what it would take.

I managed to get an image projected successfully into a 1/4" chip, but it was vignetted and flipped. I might could have solved this problem with enough experimentation (read R&D budget), but I lost patience.

In my other idea (a better one that I couldn't pull off) I established that the image being projected would, indeed, fit into a 2/3" chip, but the problems which arose were: I couldn't find a 2/3" CCD chip that was mounted on a card that would fit into the recessed pellicle, and I couldn't find a 2/3" camera that would allow me to flip the image without a bulky add on.

I've seen a homemade assist that had a right angle built into the additional relay optics to flip the image, but I don't know enough about optics to figure the elements I'd have needed to make that work.

So the long and the short is that I spent my money on a tap designed
by someone else, because the R&D might have killed me.

Frazer Bradshaw
Director of Photography San Francisco



Last year we built a custom LTR video tap for fellow CML’er Tom Gleeson from Sydney. It was quite difficult as Tom's LTR did not have any relay optics.

It is much easier making taps for 35mm cameras than 16mm cameras purely because there is usually more space and things are bigger. We used a Pulnix B&W CCD camera. We removed the CCD from the camera body, making the CCD remote from the camera body using a tiny ribbon "extension lead". We put a pellicle just above the focusing screen and used a (very) modified Nikon microscope objective as the tap lens which produced an image on the CCD of the focusing screen. Basically we made a tiny camera with the microscope objective and CCD sensor just beside the focusing screen. It was very tricky to get it all aligned. No problems with inverted images etc though. We took 12V power from inside the LTR to power the Pulnix CCD camera.

In this set up the focal length of the CCD lens is very short and it is pretty close to the curved back surface of the focusing screen. This "closeness" produces some curvature of the CCD image. It was quite a bugger of a job and took some time to get it sort of acceptable.

For a view of the outside see :

http://www.spme.monash.edu.au/~smort/panorama/LTRtap.jpg

Cya

Steve Morton

Scientific Imaging
Monash University
Melbourne
Australia


 

Sponsored by

 

 

 

 

 

 

 

CML Home CML-Tests Home

© copyright CML - Cinematography Mailing List all rights reserved