8mm Forum: Go Away, Aurora Borealis! (projection problem)

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Posted by Charles Bramlett (Member # 1246) on August 30, 2008, 09:27 PM:

Okay, so I've officially got my first super-8 projector, take-up reel, and films! I sat down tonight to screen my first film... and I seem to be experiencing some technical difficulties.

I can focus the image enough to see what's going on (mostly), but it seems like the image is being overshadowed by bright lights around the 'box' that the image is in. When watching a color film it looks a bit like the aurora borealis (hence the thread title).

Any ideas what could be causing this? Am I correct in thinking that there shouldn't be be bright lights over-shadowing the image? Do I have a lens problem? Possibly a lamp problem? Am I projecting the image onto the wrong type of surface? Has it become apparent that I don't have any clue what I'm doing??

Any help/advice would be greatly appreciated. [Smile]

Posted by Steve Klare (Member # 12) on August 30, 2008, 10:15 PM:

Wow,

I live more than 500 miles north of you and have never seen the aurora borealis!

I've never heard of a problem like this. It's acceptable for a a little light to leak up above the projector and to the side, but 100% of the light through the lens and on screen should be through the gate, and the image on film is no smaller than the gate itself, so there should be nothing but darkness other than the image.

Can you get to your gate and see that it's just a little rectangle no more than about 1/4" wide? It sounds almost as if you are missing a part in there!

Posted by Charles Bramlett (Member # 1246) on August 30, 2008, 10:46 PM:

The 'gate' is the box that the image appears within... correct?

If so, yeah, behind the lens it's just a little rectangle. All of the parts seem to be there.

Posted by Chip Gelmini (Member # 44) on August 30, 2008, 11:19 PM:

Dan Lail is a good guy from Loganville Georgia. Yep he's a member here, too. Maybe if not to far you to guys should connect and he might be able to help you out. Just a thought. I hope I am not interfering with Dan's private life.....probably not the case....lol.....how many of us reely have a life?

[Big Grin]

Posted by Steven J Kirk (Member # 1135) on August 30, 2008, 11:25 PM:

What is the projector and lens? Make and model - do they match?

Posted by Maurice Leakey (Member # 916) on August 31, 2008, 02:41 AM:

Condensation in the lens?

Posted by Charles Bramlett (Member # 1246) on August 31, 2008, 10:05 AM:

The projector is a Bell&Howell 357b. The lens says... "BELL & HOWELL 18MM-30MM f/1.6 LENS MADE IN JAPAN"

If my problem is condensation in the lens, is that fixable?

Posted by Paul Adsett (Member # 25) on August 31, 2008, 10:48 AM:

I think Maurice is right, the problem is probably the lens. First thing I would do is clean it. Look thru the lens from both sides while holding it up to the light - does it look clear? If not, go to a photo shop and get some lens cleaning solution and lens wipes. You will then be able to clean the outer surfaces of the glass. If there is condensation inside the lens, then you probably need to get another lens.

Posted by Osi Osgood (Member # 424) on August 31, 2008, 12:48 PM:

Talk about lightning striking twice!

I hav a favorite lense I use to visually inspect films, and I accidentilly dropped it in the sink, (with water in it) and though I dried out the lense, I was stunned at just how long the lense contained, (almost like a vaccum) moisture in there.

My lense is one of those "zoom" lense varieties, and I noted that there were some screws, very small, on the two sides of the lense, I unscrewed these and the top half of the lense came off, completely revealing the "moisture" on the lense! I took a non scratching cloth and dried it all up, screwed back in the
top part of the lense, and now the lense is good as new, actually a little better, as the dust is no longer is there either, so I have a better view!

I hope that this helps.

Posted by Charles Bramlett (Member # 1246) on August 31, 2008, 04:18 PM:

Hmm... I seem to have found my answer by way of an ebay seller who sells replacement lenses...

quote:
What's the matter, Bunky? You bought a projector on auction that was "untested with film but seems to work?" And the image is fogged and blurry so you can't tell if you are looking at a baby or a buffalo?

The problem is that many Bell & Howell zoom lenses were made with some silicone goo on the moving sleeves inside to give nice smooth zooming action. With time and heat, the goo has migrated to the glass surfaces so the resulting image is about like looking through a frosted bathroom window. The remedy is to take the lens apart and clean the many glass elements in multiple moving and stationary groups, trying to remember which side of each element faced forward, after which (unless you are a lens repairman) you will likely never get it back together correctly again.

He's right about the goo... that was the first thing I noticed when I opened up the lens. I may have to just bite the bullet and grab on of this guys lenses. I took mine apart and cleaned every surface that I can get to... but to no avail. Though, there are two lens surfaces that I haven't figured out how to get to yet... so I still have that to try.

BTW, those people who warn you about buying an untested projector may actually be on to something! [Big Grin]

Posted by Winbert Hutahaean (Member # 58) on August 31, 2008, 11:16 PM:

Hi all,

I think what Charles' problem is exactly waht I ask here.

Unfortunately from what the suggestions given in the abpve link, none of them was successful to fix the probelm. My ST1200 is still showing the same problem (ghosting/aurora).

Charles, please don't buy a new lens. It is expensive than your projector's price. I have clean-up all the lens and now they are crystal clear, but the aurora is still there. I don't know why .

cheers,

Posted by Charles Bramlett (Member # 1246) on September 01, 2008, 12:20 AM:

^ Looking at your thread, I think we're having different problems. When I projected mine onto the screen there was no solid box... just a big blur of colors with a faint square image in the middle. I couldn't even read the text on the screen.

But... as it turns out I don't have to buy a new lens! I was able to clean mine enough to be usable. I wound up using a flattened Q-Tip to get into the inner lens surfaces and wipe away the gunk/moisture/whatever that was screwing up the image. Now, this probably isn't the preferred lens cleaning method... but it saved me $15 today (which as Winbert pointed out is nearly what I paid for the projector) so I'll take it.

Another question... is it normal for the images on the screen to be moving a bit slow.... and should the projector smell a bit hot as it runs? Or am I now going to have a motor/belt issue? I haven't screened an entire film yet, but I'm going to try that tonight.

I'll let you know if my projector bursts into flames. [Wink]

Posted by Bill Brandenstein (Member # 892) on September 01, 2008, 01:55 AM:

That projector uses a very hot bulb - not a halogen, but big bad ol' tungsten filaments. So any dust and so forth near the heat ought to smell a little bit.

As for slow, well, it's an 18fps-only projector, so anything shot at 24 will look a bit labored. So is it slow, or is it SLOW?

Posted by Charles Bramlett (Member # 1246) on September 01, 2008, 03:00 AM:

^ You're probably right.

I just finished screening my first film from start to finish! What fun! It was from WALT DISNEY'S original feature THE STORY OF ROBIN HOOD: "Robin Hood of Sherwood Forest".

It is a 200ft reel and ran about 10-12 minutes. The characters were moving slower that what would seem normal... but not so slow as to indicate a major problem. Also, the film speed seemed to remain constant throughout. So, I'm going to assume that this is normal until I see any other indicators of a problem.

Thanks to all for your help. I'm learning a lot!

Posted by Chip Gelmini (Member # 44) on September 01, 2008, 09:54 AM:

I learned a lesson long ago.....

I was watching super 8 silent digests from major movies. My brother happened to comment the actors seemed to be moving slower than normal.

Years later, I realized these films were made for sound at 24fps. The silent digests were made for the silent super 8 machines, at 18 fps.

Likewise, speed seemed consistent throughout, yet seemed slower in general. There you go.

CG

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