Film-Tech Forum ARCHIVE: Cat 700-701 improved or not?

This is topic Cat 700-701 improved or not? in forum Film Handlers' Forum at Film-Tech Forum ARCHIVE.

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Posted by Greg Mueller (Member # 17) on 04-06-2002, 01:44 PM:

Other than the use of the LED on the 701, are there any improvements that would make the 701 a better choice?

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Greg Mueller
Amateur Astronomer, Machinist, Filmnut
http://www.muellersatomics.com/

Posted by Steve Guttag (Member # 268) on 04-06-2002, 11:12 PM:

This is real easy, the Cat. 700 is the better choice. The CCD really wants more than the red light. If you look at what the DD decoder is seeing under red light vs white light it is having much more trouble with the red light.

To prove it to yourself, use the DRAS10 program (DOS version) and hook it up to a cat 700 and press "H" for the quick histogram function...look at the right hump...it will flatten off at the top. The right hump is the distribution of what the decoder thinks are "1s" or clear bits...

Now do the same experiment with a red light system, the right hump never peaks and the ability of the system to decern a 1 from a 0 is diminished.

Then compare error numbers from a Cat 700 to a Cat. 701...the Cat 700 should (or can be made) to out perform the Cat. 701 everytime in the categories of focus and error rating.

Next comes service...the Cat. 700 uses a lamp that can be had for under $20 and is user changable. The Cat 701 uses an LED that can be had for a little under $100 and is only changeable by a service technican with the appropriate test equipment.

Steve

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"Old projectionists never die, they just changeover!"

Posted by Josh Jones (Member # 447) on 04-06-2002, 11:13 PM:

I dont see what people's big bitch with cat 700's is. I like them, plus, you dont have to sink $100 on a new LED when it decides to die. But then again, I do tend to prefer the analog world. some have said they track better, but I dont know. Greg, are you going DD now?

Josh

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"Film is made of silver, video is made of rust"
'nuf said

Posted by John Hawkinson (Member # 1135) on 04-06-2002, 11:51 PM:

Is most SR-D high-magenta (or equiv.)? Is that going to change, and will that affect this?

--jhawk

Posted by Brad Miller (Member # 2) on 04-07-2002, 12:47 AM:

Yup, I agree with Steve on this one. White light SRD readers can always outperform red led SRD readers. I prefer the 701 for one reason over the others, it is the most lightweight (but this is only of importance when you have a stack of penthouses and weight starts to become an issue). For all other applications, the 700 is the superior reader...but is that the best? Of course not. Dolby's earlier cat699 reader outperforms the 700 series readers. So my rule of thumb, the older the better! I've got a theater that has been running with the same lamps in their 699 and 700 readers for 2 solid years now, and they still track 0-1s all the time. At $20 a pop for new lamps, this is a non-issue.

Posted by Paul G. Thompson (Member # 655) on 04-07-2002, 01:30 AM:

We had a CAT 700 in one of our theaters, and it was virtually trouble-free since the day I put it in.

Posted by Christopher Seo (Member # 7) on 04-07-2002, 03:42 AM:

Steve,

quote:
look at the right hump...it will flatten off at the top.

Are you saying the right hump doesn't peak with the Cat 700? Is this something observable in DRAS for Windows?

Posted by Steve Guttag (Member # 268) on 04-07-2002, 11:56 AM:

Christopher...

Please re-read...the Cat. 700 will have it's hump flatten off (if the intensity of the lamp is properly set) whereas the Cat. 701 can not have it's hump flatten off (increasing the red light intensity will cause the CCD to saturate).

WinDras is not as good to look at this display. The Quick Histogram function is not enabled, at this time. The histogram does come up and is updated periodically, but not like if it is given full time and attention. Believe it or not, if you know what you are looking for, you can optimise the light intensity (red or white) looking at the quick histogram without an O'scope.

Steve

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"Old projectionists never die, they just changeover!"

Posted by Ken Lackner (Member # 1002) on 04-07-2002, 12:26 PM:

What's the difference between the 699 and 700?

Posted by Greg Mueller (Member # 17) on 04-07-2002, 02:56 PM:

"Greg, are you going DD now?"
Josh
It depends on how inexpensively I can do it. (I'm sooo cheap)

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Greg Mueller
Amateur Astronomer, Machinist, Filmnut
http://www.muellersatomics.com/

Posted by Aaron Sisemore (Member # 145) on 04-07-2002, 03:01 PM:

>>What's the difference between the 699 and 700?<<

The Cat 700 has a built-in power supply.

The 699's power supply is in a rack-mounted unit.

The 699 also has a little fan in it to cool the bulb (which the 700 should have kept using IMO)

The 699 uses a different bulb than the 700.

Otherwise they function the same.

-Aaron

Posted by Per Hauberg (Member # 529) on 04-07-2002, 04:16 PM:

>700 has built-in power-supply<
Yep, -and that has been the only trouble-maker in this house, due to
bad connections inside. ("Don't open Yourself - call for help !!)

Like Greg, i have to pay the bills myself, and therefore sterted DD on one projector only in 1995. -When letting projector 2 run along in 1998, the message was, that the 700 was no more made, but the 701 was just as good. -What should i think/know/do ??

Thats why i've got one of each, running now for 3½ years, no hearable difference, but with more drop-outs on 700 than on 701, when running repertoire prints with tape and bad splices and so on...

Besides, -my 701 has rollers for 35 mm only, allowing no real film bypass. -Is that standard ? The "old" 700 has 70mm rollers.

Per

Posted by Brad Miller (Member # 2) on 04-07-2002, 04:56 PM:

I don't know the part number, but I had to order the 70mm rollers from Dolby to convert my 701s for 70mm bypass operation. It is very easy to do and as I understand it, Dolby didn't bother putting the 35/70 rollers on in the first place because 99% of all installations do not need them and that helped to keep the price down.

Posted by Steve Guttag (Member # 268) on 04-07-2002, 05:39 PM:

Per,

Your Cat. 700 can be made to run and track better than the Cat. 701 without doubt.

There is a new reader in the penthouse fold by Bay Area Cinema Products and distributed by USL. It is the lowest cost of new penthouses and competes with basement readers in cost. It also doesn't use any power supply but rather uses the power already supplied to the CCD to drive it's LED.

The Cat. 699 was a machined penthouse rather than the current cast varieties. Aside from having the aforementioned 35/70 bypass rollers. It also had a spring loaded guide roller. My chief complaint with it was that the flywheel was not as massive as it should have been (corrected in the Cat. 700 and later).

If you have a Cat. 701, you might want to solder the connection that feed the EPT lamp's power wires to the power supply. The Molex connector has been known to overheat and fail.

Steve

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"Old projectionists never die, they just changeover!"

Posted by Mike Carro (Member # 232) on 04-07-2002, 05:40 PM:

I've been running my cat. 700 for a couple of years now with no problem. Granted it's in my home screening room and I don't run that much film through it. I would say though that a FRESH bulb is imperative. I had a bulb that to the naked eye was fine but it started crystalizing and threw off the reading. Once I changed the bulb it was like magic... everything was fine.

Posted by John Walsh (Member # 168) on 04-07-2002, 05:52 PM:

Actually, any of them (699, 700) are still better than the best basement reader, IMHO.

Posted by Richard Fowler (Member # 893) on 04-07-2002, 06:29 PM:

Greg,
I suppose with your machinist background you could build a clone using Component Engineering parts.

.....or you could buy a BACP for almost the price of a used 701.....
Richard Fowler
TVP-Theatre & Video Products Inc. www.tvpmiami.com

Posted by Steve Guttag (Member # 268) on 04-07-2002, 07:17 PM:

Oh there is not reason for that John. There is no real advantage to the penthouse in terms of reliability, unless you technician isn't up to the task.

In fact, in recent experiments, I was quite impressed with Kelmar's digital reader and it's ability to scan quite reliably to very low light levels (below 2V p-p on the O'Scope). I don't think I have had such results with the penthouses. My guess is it has something to do with the various grade of lenses since they all use the same CCD and board by Dolby (there is a new CCD and board out now that is more sensitive but with a focus penalty). I believe I have even heard Dolby claim that Kinoton's basement reader tracks every bit as well as their penthouses.

Anyway...back to the subject John, no mention was made of basement readers, just the Cat. 700 and 701...even the previous mentions of Cat. 699s were off subject.

Steve

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"Old projectionists never die, they just changeover!"

Posted by Ken Lackner (Member # 1002) on 04-07-2002, 10:34 PM:

Well, we all know how these threads like to go from one subject to another.

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This one time, at Projection Camp, I stuck a xenon bulb....