Minolta Compact Bellows -- not exactly light tight.

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Blcak
Posts: 34
Joined: Wed May 09, 2012 6:19 am
Location: Switzerland (originally)

Minolta Compact Bellows -- not exactly light tight.

Post by Blcak »

Hi,

I got two of these compact and lightweight bellows on eBay and managed to adapt one of them to M39 which I can use on any bayonet.
At the other side I use a simple MD>M39 adapter.

A picture can be found here: http://www.flickr.com/photos/70078248@N00/4504239200/ (not my flickr page).

I had planned to use them in the field for handheld shots. As a way to quickly change extension without having to fiddle with a larger bellows or anything like that.

In my first test shots I had relatively low contrast, so I painted anything shiny black. But when I get out with them to direct sunlight, the problems get worse. So I suspected a light leak of some sort. While the bayonett (usual weak spot for light leaks, isn't it) indeed has some leakage, fixing that didn't change the situation either.

So last night I used a 3W LED at the inside... and tada... the bellows material is not tight. I can see the light inside the bellows -- bummer.

So now I wonder what I could do to change that. One thought I had was maybe painting the inside or outside. The paint would have to be of high density, but flexible and long lasting. I don't want it to make the bellows less flexible, and I don't want the paint to come off. Another, more drastic option would be to get tight bellows and replace the Minolta bellows.

Do you guys have any ideas?

abpho
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Location: Earth

Post by abpho »

Those are pretty cool little bellows. To bad about the light leak. I can't offer any suggestions on how to repair the bellows, but will listen in case someone else can. I'd like to know for my own use.

Thanks.

johan
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Joined: Tue Sep 06, 2011 7:39 am
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Post by johan »

I had this on my bigger size bellows, and discovered through torch testing that it was a poor fit with adapters that was to blame. Black electricians tape solved it for me
My extreme-macro.co.uk site, a learning site. Your comments and input there would be gratefully appreciated.

Blcak
Posts: 34
Joined: Wed May 09, 2012 6:19 am
Location: Switzerland (originally)

Post by Blcak »

To clarify, there are no specific leaks, those I could fix easily with a bit of tape. The whole bellows material is not 100% light tight. It's a bit translucent.
It's that way with both of them, so it's very likely a design flaw affecting all of them.

elf
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Joined: Sun Nov 18, 2007 12:10 pm

Post by elf »

Acrylic paint scrubbed in with an old soft toothbrush may work. I've been thinking about using this method to make another bellows. You may want to practice on some scrap material to get the right thickness and number of coats to do.

Craig Gerard
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Location: Australia

Post by Craig Gerard »

A spray can of 'Plasti Dip Flexible Rubber Aerosol' may be useful in this situation. I haven't used the product but made a note of it when it crossed my path.

Apply gradually in very thin layers. Some people are painting their cars with this stuff...plenty of videos on YouTube.

*Use at your own discretion.


Craig
To use a classic quote from 'Antz' - "I almost know exactly what I'm doing!"

Blcak
Posts: 34
Joined: Wed May 09, 2012 6:19 am
Location: Switzerland (originally)

Post by Blcak »

Craig Gerard wrote:A spray can of 'Plasti Dip Flexible Rubber Aerosol' may be useful in this situation. I haven't used the product but made a note of it when it crossed my path.

Apply gradually in very thin layers. Some people are painting their cars with this stuff...plenty of videos on YouTube.

*Use at your own discretion.


Craig
Hm, that sounds interesting, although I worry that it will come off at the edges at some point it in time. Not sure how well it will react to strain.
They're able to peel it off easily in these videos. That might just happen at the edges where the bellows is compressed the most.


@elf: That sounds like it might work. I've seen acrylic paint on clothing before and it didn't come off easily.

Blcak
Posts: 34
Joined: Wed May 09, 2012 6:19 am
Location: Switzerland (originally)

Post by Blcak »

I did some reading in the world of large format photography.

Plasti Dip has been mentioned once with good results.
Other people generally seem to prefer acrylic paint.

I think I'll give Plasti Dip a try, why not.

dwight_talley
Posts: 30
Joined: Thu Jun 07, 2012 4:53 am
Location: Richmond Virginia
Contact:

Post by dwight_talley »

You can have some new bellows made, in different colors if you want. I have had some medium format camera bellows replaced before and it looks great. Here is a link to a site that makes them.

http://www.sandehalynch.com/isolette.htm
Dwight

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