Rehousing LA7200. Help needed!

[Tito Ferradans]

Hi everyone!

I've recently started to work on this project that might interest other users in this forum. I'll need some help in the process. One of my main interests in this development is to keep the whole process "open-source" so anyone can reproduce the rehousing based on what we share in this topic, staying as far as possible from a monopoly with ultra-high prices! :D

We must agree that the Panasonic LA7200 is an interesting lens, right? But, as all others, it has its quirks and downsides, mostly related to its body design.

Plastic is just cheap and fragile. It's very easy to lose parts of it (tiny screws, mostly), not mentioning the deep thread that requires more step rings and the square-front which makes diopter use way more complex than should be. Also, its weakness for close focus or shallow apertures is very well known.

What if all this could be solved in a big move? What I'm planning is a full rehousing of this lens, improving every aspect mentioned in the previous lines.

- Round, full-metal body
- Internal alignment mechanism based on three screws instead of one (like a clamp)
- 67mm, exposed rear thread
- 114mm front thread, with various step-downs that won't increase the distance from the front element (non-standard design)
- Very easy to remove glass for cleaning
- "Focus adjustable", based on a push-pull concept, for closer focus, or longer rack focusing.

Sounds good?
What else do you guys think could/must be improved?

I already have multiple sketches around these ideas but haven't started precise modelling yet, nor have contact with any CNC owners that might be interested in the project.

If anyone wants to partner, please, speak up!
My direct email is ferradans at gmail.com

ps - the focus part is mostly based on this video, but with a body around it! hahaha

https://vimeo.com/23042151

[JohnBarlow]

Is this a Brazilian thing?

 

First we had Apefos and now you - must be something in the water :)

 

Any decent type of housing, properly precision engineered with focus helicoid etc is gonna cost $$$$$$$

 

A cheap alternative similar to the video but with more mojo would be adapting old Hasselblad bellows - just mount the glass font and rear and you're done.

 

http://www.ebay.com/itm/Hasselblad-40223-Round-Bellows-NICE-662-WARRANTY-FREE-USA-SHIPPING-ROBERTS-/140951671540?pt=LH_DefaultDomain_0&hash=item20d15fd2f4

[Tito Ferradans]

Hell, I hope this goes nothing like Apefos! He charges gold for some tubes and butterfly screws. hahaha! We've had disagreements before, but he has more resources than I do. :P

 

I don't intend to have a focus helicoid, the bellows idea is rather interesting, but it looks like a mess and doesn't solve all problems. My plan is to do the design and modeling all by myself, and then find someone with a CNC to cut it out. Someone with a product-design experience could give me a hand! haha

 

I don't believe that it MUST be so expensive. The main goal is to keep it as low-cost as possible, since LA7200 prices are insane. But, as noted, I don't know the costs for this specific kind of machining. More tips here could be useful as well! :D

[tony wilson]

i have been working on something for quite  a while..the main issue is cost accuracy of machining for a rehouse.

as soon as you introduce focus adjustment in it will add even  more.

finding an engineering company that will take back badly made metal work is always a problem.

many times ends in tears for the customer.

the engineer says nothing wrong with it you say it is shit

mass production cuts costs but as i have found nothing worse than finding you have a 1000 of something that does not work.

my project has been delayed because i feel until i can make something better than the plastic crap of panasonic then no point.

it can be done but the cost is the issue you soon hit the brick wall of the customer making do rather than upgrading.

[soupkitchen]

so tony is there anywhere you'd recommend for one off jobs like this? Surely somewhere like TLS would be able to rehouse it in a tube AND make it focus-able for less than an Iscorama costs.

[tony wilson]

i am working on it at the moment.

as i said the first one which was simple budget was bad.

it can be done easy but will look shit and be not as refined as the plastic panasonic.

the only way is a kit that you do in your home.

 

take apart an anamorphic try to realign it is a bitch i send my stuff to bernie o in the states now cos i have not got the patience.

machining with this level of close tolerance is easy with lots of money difficult with little.

i cannot even sell properly machined clamps people want cheap shit.

 

i will build some kind of alignment in try to make it easier than the normal retention ring pain.

 

i can do something very nice and i will but probably will make 20.

i scrapped the 1st as i said earlier has to be better than existing or no point.

i have enough old movie close up diopter stock for 15 of them..even have some large +0.25 achromats but they are 3 times as heavy as the anamorphic.

the most important part of it for me is the profound question.

would chuck norris use it.

would he feel manly and comfortable with this lens in his giant hands.

i have spoken to his people and they have told me never to call them again unless i have a job offer, for this one man slaughter house.

since i have taken up the the mantra what would chuck do i find decision making so much easier :)

[Tito Ferradans]

some more information and details of what I had in mind. I've stopped developing due to lack of time! If anyone has any insights over this, please, speak. hahaha.

 

whenever I find a friendly engineer, I'll update this!

 

 

 

[Gábor Ember]

Try Google Sketchup for 3D modeling

[Tito Ferradans]

Yeah, I already did some stuff with google sketchup, but the program has some serious problems when dealing with round things. They're not perfectly round, as that would consume too much processing power, and that's not sketchup's purpose. :P

 

It must be CAD, in order to be directly transfered to a CNC machine, or 3Ds Max.

[Gábor Ember]

I see. Then there is your answer, use CAD for modeling and use Max for previsualization, render.

[Tito Ferradans]

I just don't know how to use them - YET! hahaha

[Gábor Ember]

I can do renders for you in MAX, put materials on glass and metal parts so they look glass and metal, try out different color schemes, if you want. I cannot help you in CAD, that's the hard part :(

[Tito Ferradans]

Thanks a lot, dude!  As soon as I have something, I'll send you a message! :D

[Gábor Ember]

Alright

[Gábor Ember]

Check this out: http://www.emachineshop.com/ If I understand correclty you can use their free CAD software to design your parts, send it and the company creates it in their machine shop. Now I don't know if they ship to Brazil. I guess you can find other companies like this.

 

 

Edit: I just did a quick trial and their software looks pretty easy to handle. You can preview the model in 3D in one click and the program should calculate the cost of the parts and also shipping. Their site says that international shipping is available.

[Tito Ferradans]

Wow, this looks amazing. I watched the tutorial, and as soon as I have some free time, will see if it can do what I need! Thanks Gábor! :D

[Stuart Hooper]

Exciting idea.  I contacted Duclos a few months back about a rehousing and they declined to take it though I indicated price wasn't a real problem.  (I've got a producer who likes to shoot on his GH3 + 12-35 and LA7200 and doesn't really care what needs to be done to make the setup even better, but doesn't want to go to cumbersome manual primes for the money)

 

I don't know if it's because they have 'better' things to do or if it's particularly challenging, but they turned me down.

[tony wilson]

the glass is the best of a shoddy bunch including the optex and century. panasonic clearly had superior quality control than the other 2 companies in these projects.

duclos could offer a sollution. what would you like a smaller metal version of what you have or one with some focus movement. at what financial price point does it become do able for the company and burst out laugh loud or shock for the customer. it is all possible. but it is always about the money. we live in a society built on mass production cheap nasty china shit and plenty of near slave labour.

it is all about penny cost not the value.

 

throw some cash my way and you can forget the duclos de click special company : )

[Matthew Marshall]

I like your design. Might make one of my own if you dont mind. Gonna add a little personalization touches to it, probably a ruler on the base. For different lenses then you can have precise measurements recorded for easy setup.

 

I was also thinking of a custom housing and using probably like a vintage camera billows to reduce light leak between the front lens and the one attached to the prime lens. In addition making the housing itself move as well.

 

Also if you wanted to get real technical. Add gears, so when zooming with a lens that has front movement, it automatically adjusts the anamorphic front to the right distance.

 

Technical stuff but small improvements i might look at. I have access to a 3d printer so fabrication should be fairly simple.

 

Great idea btw.

[silvertonesx24]

Hi everyone!

I've recently started to work on this project that might interest other users in this forum. I'll need some help in the process. One of my main interests in this development is to keep the whole process "open-source" so anyone can reproduce the rehousing based on what we share in this topic, staying as far as possible from a monopoly with ultra-high prices! :D

We must agree that the Panasonic LA7200 is an interesting lens, right? But, as all others, it has its quirks and downsides, mostly related to its body design.

Plastic is just cheap and fragile. It's very easy to lose parts of it (tiny screws, mostly), not mentioning the deep thread that requires more step rings and the square-front which makes diopter use way more complex than should be. Also, its weakness for close focus or shallow apertures is very well known.

What if all this could be solved in a big move? What I'm planning is a full rehousing of this lens, improving every aspect mentioned in the previous lines.

- Round, full-metal body
- Internal alignment mechanism based on three screws instead of one (like a clamp)
- 67mm, exposed rear thread
- 114mm front thread, with various step-downs that won't increase the distance from the front element (non-standard design)
- Very easy to remove glass for cleaning
- "Focus adjustable", based on a push-pull concept, for closer focus, or longer rack focusing.

Sounds good?
What else do you guys think could/must be improved?

I already have multiple sketches around these ideas but haven't started precise modelling yet, nor have contact with any CNC owners that might be interested in the project.

If anyone wants to partner, please, speak up!
My direct email is ferradans at gmail.com

ps - the focus part is mostly based on this video, but with a body around it! hahaha

https://vimeo.com/23042151

 

I built something like this video a few years ago. It was pretty easy, just cut the LA7200 and then use a macro focusing rail and some screws to mount the outer part. I was able to focus within a foot or two, but eventually gave up on the LA7200 altogether as I found the lack of sharpness unusable.