8mm Forum: Original Bolex H8 Rex 4

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Posted by Luigi Castellitto (Member # 3759) on October 22, 2013, 07:21 AM:

Hi,
i have a request for clarification, for a real Bolex experts! [Wink]

The Bolex H8 Rex 4 with that kind of objectives was originally sold? As reported here? http://www.bolexcollector.com/cameras/h8rex4.html

Or WITHOUT ANY objectives (and the user chose which add)?

This:

http://www.ebay.it/itm/BOLEX-H8-REFLEX-MOVIE-FILM-CAMERA-PAN-CINOR-1-1-9-f-8-40mm-ZOOM-LENS-/231077156948?pt=Altro_Fotografia&hash=item35cd459854&_uhb=1

is a H8 Rex4? It's clear that the Pan Cinor objective was bought separately by the user, but he changeds something?
Thank you!

Posted by Luigi Castellitto (Member # 3759) on October 24, 2013, 07:25 AM:

None of the official Bolex websites can give me an answer. [Frown]

(
I need a "elder" user who remember when the H8 Rex 4 was sold only with the camera body, or lenses, and if so with the lenses, which ones?

P.S. in the reflex H8 REX 4 was even included the galilean viewfinder that was at the side of the camera?

Posted by Guy Bodart (Member # 4007) on November 05, 2013, 09:29 PM:

The H8 RX4 cames with 3 prime switsr lenses or the 8-36 Vario Switar. I do not know if the Pan Cinor will work on it. Call Dieter at http://www.bolexusa.com . He is the only good Bolex/Importer technician in the US. He knows everything about Bolex

Posted by Bryan Chernick (Member # 1998) on November 05, 2013, 10:27 PM:

I have both the Pan Cinor and the 8-36 Various Switar for my Rex 4. They are both great lenses and are both designed for the H8 Reflex cameras. The Pan Cinor has H8 RX printed on it indicating it was designed specifically for that camera. They are both C mount lenses, not D mount.

I would assume you could buy it with any of the lenses you wanted since they had several that we're specifically designed to work with the H8 Rex.

This is from the Bolex Collector site.

quote:
H8 RX Lenses
Kern introduced a new line of Switar lenses designed specifically for use with the H-8 REX: a 5.5mm f/1.6 wide angle, a 12.5mm f/1.3 standard and a 36mm f/1.4 telephoto. These lenses included a new pre-set diaphragm with control levers; a specific diaphragm setting could be locked while allowing the diaphragm to be fully opened for focusing, and then returned to the previously set f-stop without looking away from the viewfinder.

The lens mount on the H-8 REX was the same 1" thread diameter as found on the standard C-mount of the H-16 and other 16mm cameras. However, the optical distance between lens seat and film plane was 15.305mm (compared with 17.52 on 16mm). [2] The lenses designed specifically for the H-8 Reflex were identified by the letters "H8 RX" inscribed on the lens barrel.

And this.

quote:
Pan Cinor 40 RX
Introduced in 1962 and designed for the H-8 REX. It offered a 5:1 zoom range from 8mm to 40mm, with a maximum aperture of f/1.9.

You can mount the Octameter viewfinder to the film door. This does come in handy since the reflex viewfinder can be very dim and hard to see through.

Posted by Luigi Castellitto (Member # 3759) on November 06, 2013, 05:58 PM:

Thanks, guys. With my Bolex was the Pan CINOR 40 RX, and, as Bryan says, is an excellent optic.
Also confirm the viewfinder really dark, weakness of H series, but with the help of the Octamer (or "matte box" of link?) can be overcome.

Posted by Luigi Castellitto (Member # 3759) on November 07, 2013, 06:32 AM:

Here: http://www.bolexcollector.com/accessories/view50.html
i read that there was Octameter for H8 and H16, separately.
I got one for H16, but does not seem so incompatible, i see they have different focal lengths, but be comfortable with differences focal lengths i think also depends on the optic mounted, right?
I think that the little window for the parallax included is compatible, you say?

Posted by Fabrizio Mosca (Member # 142) on November 07, 2013, 06:52 AM:

Luigi, what is important is the "ratio" between the lens and the frame size.
I mean that you may use the octameter for 16 in the H8 simply considering that a 25mm lens for 16 will correspond to a 12,5mm lens for 8mm, 50mm to 25mm and so on.
The correction of parallax depends on the distance between camera and subject and not on the gauge of the camera. I think that all the octameters have the parallax feature.

Posted by Luigi Castellitto (Member # 3759) on November 07, 2013, 07:25 AM:

Right, Fabrizio, having a 8-40 zoom, the Octameter can essentially go well, the one to H16 have focal lengths of 10mm (with an external mask), 16mm, 25mm, 35mm, 50mm, 63mm, 75mm, 100mm and 150mm, you give up the short focal lengths, but with the "ratio" that you say can go well. There was another external mask that also enabled 5.5mm...
The Octameter for the H-8 have focal lengths (with "ratio" of 8mm) of 6.5mm, 9mm, 12.5mm, 25mm, 36mm, 50mm, 63mm and 75mm, we're not far...

Posted by Luigi Castellitto (Member # 3759) on November 14, 2013, 04:09 PM:

I'm trying the H16 Octameter on a H8, but i must say that "half" considered, for example: focal 16mm on Octameter and 8mm on Pan Cinor zoom mounted on H8 not do not reproduce the same image, perhaps because in the calculations need not consider the exact half ?

Posted by Fabrizio Mosca (Member # 142) on November 15, 2013, 01:34 AM:

Considering that the 8mm frame is 1/4 of the 16mmn one, the ratio should be roughly 1:2 with respect to the angle covered by the lens. How much is the discrepancy? And how much is this discrepancy with the image in the frame?
In addition, consider that all the loupes don't cover the exact image of the frame but some have a smaller coverage other bigger coverage (consider, e.g. all the arriflex from BL series, that have the indication of the frame area, and some of the TV area and the safe area for projection).

Posted by Luigi Castellitto (Member # 3759) on November 15, 2013, 05:46 AM:

The discrepancy is not pronounced, we could almost be.
It could also be the reflex viewfinder of H8 Rex4 (on it the image is always a wire closer) that magnifies a bit'!

Posted by Fabrizio Mosca (Member # 142) on November 15, 2013, 06:21 AM:

The check should be performed on the elements that are present in the picture and not on the magnification the viewfinder has.

Posted by Luigi Castellitto (Member # 3759) on November 15, 2013, 06:55 AM:

Yes, for the test i used a picture, beyond magnification. Anyway, we're almost there... I have to test better, perhaps with more light!

Posted by Luigi Castellitto (Member # 3759) on November 15, 2013, 06:25 PM:

Looking at the light, i can say that we are ok, Fabrizio, excluding the "frame" that has the viewfinder, but not the Octameter.
So, for those interested, i confirm that can use the Octamer of Bolex H16 on a H8, but halving the value of focal length. Not very practical but possible.

Posted by Luigi Castellitto (Member # 3759) on January 01, 2014, 02:27 PM:

Now I use for some time the H8 Rex 4, but I still have not used the famous viewfinder (non the Octameter!) dark and grainy of H8 when shooting indoors (outdoors I'm used to).
I have a quick question to the experts more accustomed to (I know that the prism deflects 20% of the total light in the viewfinder, but my question is another):

what you see in the viewfinder is necessary to consider the SAME to be on develop film or should always consider that what you see in the viewfinder is always a BIT' DARKEST(what a lot?), underexposed, on the result of the develop film?
Thank you!

Posted by Paul Mason (Member # 4015) on January 02, 2014, 07:49 AM:

Luigi,
The correct exposure using the Bolex H16 and H8 reflexes is given by the lens aperture on your exposure meter for the "adapted" exposure for your film transport speed. For example with a variable shutter fully open giving 133 degrees shutter opening and the camera running at 24 frames/second would require 1/65th second. The adapted exposure compensating for the 20% light diverted by the viewfinder is 1/81 second.

Posted by Luigi Castellitto (Member # 3759) on January 02, 2014, 09:20 AM:

True, Paul, I have the manual of H8 and it indicates the compensation on shutter, but the two light meters that I use, Sekonic, are adjusted using the frames speed and the iris aperture stop, not shutter times; it's more difficult to get the shutter times.
The manual reports, for example, for 18 frames per second set to 1/60 instead of a 1/50 and, as you say, for 24 frame, 1/80 instead of 1/64. For single shot, example, 1/40 instead of 1/30, then there are changes made to the variable shutter adjustment (option that have the H8), for example: 1/137 instead of 1/110, when shutter closed in half.

What I wonder is the corresponding f-stop, for "cinema" light meter that not have shutter time setting.
If so... 1/60 to 1/50 there is a very small difference, you have to move the iris lever really little (how many?). And image on viewfinder, indoors, remains a bit 'darker, it's true?).

P.S. I also have Gossen light meter for Bolex, that is already set up to compensate. Very comfortable for Bolex H reflex!

[ January 02, 2014, 07:17 PM: Message edited by: Luigi Castellitto ]

Posted by Luigi Castellitto (Member # 3759) on February 15, 2014, 06:48 AM:

Guys, apart from the fact that I use the light meter Gossen specifically to recover lost uce the viewfinder, I wanted to ask you another question: what you see in the viewfinder, the famous grainy and dark, is really what will be in the film? It seems to me that, despite the recovery of 20% of light through the shutter (or the Gossen prepared), needs always open half a stop more than what the light meter indicates.
What do you think?
I mean: the light meter is already set up to retrieve a value, already comprised of greater openness to compensate for the light lost in the viewfinder, but, to this, we must add another half of stop. This is because the viewfinder seems to me, however, too dark!

Posted by Fabrizio Mosca (Member # 142) on February 15, 2014, 08:36 AM:

You can't base the aperture on what you see in the viewfinder and your feeling, because it also depends on the sensibility of the film you use.
If you look through the viewfinder the same scene and set the aperture for, e.g. a 64ISO and a 500ISO, you will have a completely different image on the viewfinder in terms of light.
Follow what the light meter says and compensate the loss of light through the prism (if not already compensated).

Posted by Luigi Castellitto (Member # 3759) on February 15, 2014, 01:26 PM:

Right, Fabrizio, just wondering because I have found differences between the various shot with various type of films.

Am I wrong, or is there also to say that the differences between the various settings with the shutter are not visible BEFORE you start shooting, because the shutter is not yet in operation?

The specific Gossen lighmeter for H reflex Bolex that i have, this: (http://www.bolexcollector.com/images/accessories/misc60_5b.jpg) is already set up to compensate for the loss of the light (20%) with the reflex of Bolex H, but remains difficult to manage the dark and grainy viewfinder of H series, perhaps never makes fine (and Octamer viewfinder does not make the iris, of course).

Posted by Fabrizio Mosca (Member # 142) on February 15, 2014, 03:47 PM:

What do you mean with:
"Am I wrong, or is there also to say that the differences between the various settings with the shutter are not visible BEFORE you start shooting, because the shutter is not yet in operation? "

Does the lens you use have a mechanism that keeps the iris open until you activate the motor of the camera?

Posted by Luigi Castellitto (Member # 3759) on February 16, 2014, 08:56 AM:

Sorry, I have explained badly, Fabrizio. I meant that in the viewfinder you can not see the difference in brightness of the variable shutter.

Posted by Luigi Castellitto (Member # 3759) on February 17, 2014, 01:08 PM:

Welcome advice from other users who use the dark viefinder of Bolex H series! [Smile]

Posted by Luigi Castellitto (Member # 3759) on February 24, 2014, 05:42 PM:

Simply put, I'd like to know: if the brightness of the scene visible in the viewfinder have 20% of the light (deflected by the prism), then we must consider that the light will arrive to tehe film is the remaining 80%, much clearer. Am I wrong?

P.S. As regards the setting of the iris, on that there is no problem, being the Gossen Bolex already prepared for the light to arrive. Then the "80%" is the right amount of light need with emulsion.

Posted by Bryan Chernick (Member # 1998) on February 24, 2014, 06:15 PM:

Don't worry about what you are seeing through that viewfinder, they are notorious for being dim. I use 1/60th of a second for 18 fps and 1/55 of a second for 16 fps with great results. To focus open the iris all the way and then return it to the proper setting when you are ready to shoot. That will give you a brighter view. Not only does the viewfinder only give you 20% of the light but you are also looking through the iris so if you have a high f stop you will have a hard time seeing anything. What you see in the viewfinder is going to look a lot worse than what you will see on the film. Since you are looking through the lens you don't need to worry about parallax correction, your framing will be correct. The following web site has a great tutorial on the H8 Reflex, it's how I learned to use it:

Bolex H8 Reflex - Super 8 Man

Posted by Luigi Castellitto (Member # 3759) on February 24, 2014, 06:30 PM:

So, Bryan, you confirm to me that the film will be 4 times brighter than what you see in the viewfinder? 20% x4 = 80%

And in that 80% is the right percentage of light that wants the film emulsion, because my Bolex Gossen (which manages more light alone) or set 1/60 instead of 1/50 (for example 18 fps and shutter fully open) carry the right light?
Basically, it's how to get 120% of the light, so the 20% "go away."

EDIT: Yes, i use the lever on the lens to open a few moment the most of the iris, otherwise, especially at iris very closed, you would not see anything, not even in focus!
Profit for the link, thank you!

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