This is topic Lens sizes in forum Film Handlers' Forum at Film-Tech Forum ARCHIVE.
To visit this topic, use this URL:
https://ft-forum.com/ft/cgi-bin/ubb/ultimatebb.cgi?ubb=get_topic;f=1;t=004053
Posted by Sam Hunter (Member # 1119) on 10-02-2002, 10:26 AM:
I am trying to figure out the correct focal length for a couple of lenses for my setup and I am not sure I have it right.
My throw will be 18', my screen is a 6' X 6' and i have a B-L Cinemascope lense attachment. I want a lense just for flat and another to attach to the scope lens. I used the lens Calc program on the site here but Iceco tells me I am wrong.
I came up with a 70mm lens for Flat and a 124mm lens for scope.
Granted I am not sure that all Scope marked film are the same but I gotta start somewhere.
Anyway could somebody help me out here as I am a complete novice at this.
Thanks!------------------
Samual Hunter Sr.
KC5ZSL
Posted by Aaron Sisemore (Member # 145) on 10-02-2002, 11:10 AM:
First off, I am going to assume that you are going to properly mask down that 6x6 (square) screen to get a proper aspect ratio for both flat and scope (common width). To not do so would be inviting ridiculous image cropping.With a common width assumption in mind, I get the following numbers for a 18' throw:
1.85:1 Flat: 63mm (60 would be your closest next size) for a 6'x3'3" picture.
2.39:1 Scope: 125mm for a 6'x2'7" picture. You may also have to modify the B&L anamorphic to get it to focus at 18 feet.
Also, IMO, I would avoid ICECO like the plague. 
-Aaron
Posted by Jeff Taylor (Member # 443) on 10-02-2002, 12:18 PM:
Aaron: Steve Krams speaks well of you, too :-)
Posted by Manny Knowles (Member # 1171) on 10-02-2002, 03:22 PM:
If you are buying old technology or any other used stuff, you have to be picky no matter who you are buying from.FWIW, I have had a number of good experiences with ICECO on four installations and several upgrade projects. In those instances where something was not to my satisfaction, I found them to be eager to make things right.
My intention here is not to disagree with Aaron. He has helped me out on this website by providing really useful information a number of times. I respect Aaron.
The folks at ICECO have become friends of mine over the years and I would not feel right if I let a negative comment sit out there alone when I know I have had a different experience. I just felt I had to weigh in from my own perspective.
~Manny (fighting for truth, justice and the American way).
Posted by Aaron Sisemore (Member # 145) on 10-02-2002, 04:02 PM:
Of late, I have had more bad experiences than good dealing with ICECO.If they could deliver on my needs and not beat around the bush and procrastinate (case in point: a pair of Norelco DP75 70mm spindles that I have been needing for a client since frigging LAST YEAR, they originally claimed to have some in stock, and I still have neither answers nor spindles, they keep saying that they will 'check the warehouse', yada yada...) then I would be happy as all get-go with them. They have delivered on getting us lenses in a pinch in the past. I was very satisfied, and thats one of the reasons I went to ICECO looking for these spindles.
Until I see better service from ICECO, I cannot recommend them to anyone. 
-Aaron
PS: Shortly after posting the above commentary, I decided to give ICECO one final try re: the DP75 spindles. I spoke to Dara, who will check the warehouses one final time, and she says she will call me back with a 'yes' or 'no' answer, which I will accept, and at that time I will withdraw any negative opinions I have with the company.
-AS
Posted by Richard Fowler (Member # 893) on 10-02-2002, 05:02 PM:
When ICECO says they will check the warehouse it could mean one of three covering more than two city blocks plus various storage trailers. Steve is a friendly competitor but we have different niches of customers so we rarely compete...but we have the same grief with certain vendors 
Richard Fowler
TVP-Theatre & Video Products Inc. www.tvpmiami.com
Posted by Steve Kraus (Member # 476) on 10-02-2002, 05:15 PM:
I think that's where I got the 35mm magazine spindles for a JJ I used to own. And a flywheel for the penthouse. I don't recall any problems with the transaction.
Posted by Sam Hunter (Member # 1119) on 10-02-2002, 10:59 PM:
Aaron, what modification are you refering too?
Also, I was thinking flat was 1.37:1 and scope was 2.35:1 ratio.
Let me try this tact, If I have a film or trailer marked "FLAT" or "SCOPE" then is this a fixed standard nowadays?
So much to learn, gee whiz.....------------------
Samual Hunter Sr.
KC5ZSL
Posted by Aaron Sisemore (Member # 145) on 10-03-2002, 12:20 AM:
The front of the lens has to be disassembled and a small section cut off of it. There might be a site that gives more detail (possibly in the manuals section here even) on exactly what has to be done.'Flat' these days implies an aspect of 1.85:1. Usually the other non-anamorphic 35mm rations are identified by their ratio (1.66, 1.75, 1.37) rather than generically as 'Flat'
Virtually all non-anamorphic films (unless specified otherwise) are intended to be projected at 1.85:1 aspect. Many are also hard-matted at their respective aspect which would result in 'letterbox' effect if projected at 1.37:1
-Aaron
Posted by Frank Angel (Member # 248) on 10-03-2002, 03:01 AM:
I am in the same boat with Manny -- Steve Krames and Dara and their tech guy Fernando have done very good by me over the years and have come up with odds and ends that no one else could -- ICESCO is a great resourse for used equipment of any imaginable make or model. I too feel they are upstanding in their business dealings and I just needed to put that on the table as my experience with them. They have outfitted three projects that I worked on and the clients as well as myself couldn't have been happier. I find them very personable as well.Again, I am not contradicting Aaron. just that my experiences have all been positive, and that should be out on the table as well as any negative.
And Sam, you only have to worry about 1.66 and 1.37 if you are running older prints....almost anything prior to 1950 will be standard Academy (1.37). But you can't assume a current flat release necessarily will be 1.85 -- if you run foreign films, you will find that Europe still holds on tight to 1.66 and plenty of films come in marked 1.66. Then again, they don't even have to be foreign films -- I just ran the premiere of SKINS, and it was 1.66 -- stated so right there in the leaders (not hand-written, but in the emulsion scribble).
This wasn't hard matted but actually a full-frame print, so I imagine it was composed with its later video life in mind. Going 1.66 was a compromise for the theatres so as not to make it look to clostraphobic cropped to 1.85, as many will most likely play it anyway.
Frank
Posted by Sam Hunter (Member # 1119) on 10-03-2002, 11:44 AM:
Aaron, there is only one way to change the focal length of these lense and that was easily accomplished, now whether or not it will focus sharply at that short a distance is another thing. Anyway I will be checking with Iceco anyway as I have had good dealings with them so far.
Thanks so for the info guys.P.S. Aaron, what kind of brew are you holding in your pic?
------------------
Samual Hunter Sr.
KC5ZSL
Posted by Aaron Sisemore (Member # 145) on 10-03-2002, 12:09 PM:
It isn't really an issue of 'focal length' per se, but a problem with the ability of the astigmatism 'distance ring' adjustment on B&L anamorphics to go far back enough to allow the lens to focus at extremely short throws. Cutting out that section of the lens housing allows the element to go back far enough to accomplish this.The beer in question is Star Trek Romulan Ale.
-Aaron
Posted by Sam Hunter (Member # 1119) on 10-03-2002, 12:14 PM:
That is the coolest "drink" I have seen in a while 
Hows it taste? Where did you get it?Anyway I removed 1/4" from the collar and sleeve and lengthened the rail slots and now I get some range on it now.
------------------
Samual Hunter Sr.
KC5ZSL
Posted by Aaron Sisemore (Member # 145) on 10-03-2002, 08:10 PM:
Glad you got that lens to work out.As for the Romulan Ale:
It doesn't taste too bad, it is a mildly hoppy pale ale with a twist: it's dyed blue (for authenticity to the 'Romulan Ale' on Star Trek).
It's made in El Salvador for Viacom Licensing Corp.
and the only place (besides Ebay) I have ever seen it for sale has been the 'Star Trek Experience' at the Las Vegas Hilton (where the pic of me was taken). They also have it and several other 'Star Trek inspired' brews on tap there.
-Aaron
Posted by Pete Lawrence (Member # 130) on 10-03-2002, 08:44 PM:
Romulan Ale can be purchased on line and shipped to most states.
$9.95 per six-pack, $39.50 per case http://startrekexp.com/shop/index_moogie.html
If you prefer Klingon Blood Wine they also have that and several other selections too.