Alain:

I followed the ground glass tutorial circulating and it seems to work just fine. It could probably work either way, though I found grinding the filter, versus grinding the glass with the filter, to have more swift results.

John: I "need" a condensor? I'll wait and see on that.

- jim

Giroud,
I think the lighting calculations apply equally to both film and video. There is just a difference between the calculations just like a British pound is greater than the US dollar but people in England might earn less gbp in a month than people earn dollars in US. I am very new to this myself but i think the increase in ISO foot candles number means the decrease in the f stop(brighter). Since one third of a stop is the maximum difference a human eye can spot that is the same way ISO numbers increase. Let's say we have two film stocks one is 100fc and the other is 200fc so the difference of going from 100fc stock to 200fc stock in the sensitivity is 1 full stop faster (double the light). I hope i touched your question in some way please correct me if i am wrong which is very possible.

Reverse T-mount
 

Giroud: the $10 adapters at surplus shed are for attaching a T-mount lens to your camera, NOT a t-mount tube to an SLR lens. The latter requires a so-called reverse t-mount adapter which is hard to find. You can custom-order if you're willing to pay extra.

Overall, t-mount is a good solution, but the 42mm diameter won't give you the full 36X24mm image.

Is T-Mount 42 or 48? minimum diameter for 35mm film size is 43.65mm

Yup - 42mm.

http://www.fli-cam.com/FLIsupport/tmount.htm

This article also mentions a 'standard' 2" threaded tube commonly used for telescopes. There are tons of ATM (amateur telescope maker) supply shops which would offer 'standard' items like this, I'd think.

AFAIK, it's 48mm OD / 42mm ID.

in fact the 42mm of a T-mount is ok because the picture on the glass is 36x24 but in between the gg and the lens it is a lot smaller.(just look a the rear lens of a 35mm lens it is very small).
and anyway there is a lot of 35mm sold with this mount so it should work.
So you can solve the mechanical problem of mounting lens on the gg with T-mount but for sure after the GG you will need someting bigger for the condenser and the macro lens.
I thing 52 or 58mm is fine depending your camera.
I think it not worth to spend too much energy on this kind of problem since we can find many relatively cheap way of mounting a 35mm lens over a tube.
the real problem is after the GG ( GG included if you plan to move it) and it is where energy must be put.
to Roman Shafro: yes you are right the t-mount adapter is for mounting T-lens on pentax,nikon etc... but if you are looking for a T-mount support (like me) you will probably need a piece of it (the T-receptaclle).
My opinion is that it is probably better to buy some cheap T-mount lens you can leave on your mini35 than use your expensive nikon lens for weird use.
The advantage of this is you can finish the mini35 and purchase the best lens you need instead fighting with silly mechanical problems.
For sure the ones that are looking for the cheapest price will be reluctant to spend 40 or 100 $ for a lens but regarding the price for the real mini35, i think it the total price stays under 200$ we are still in an interesting situation.
My goal here is to build a mini35 for cheap, with if possible refurbished parts, but in a way that allows a reproduceable build by generating for example a part list with links to provider that allows next people to make their own project.
For instance:
(price including international shipment)
25$ for aluminium grit
5$ for the UV glass filter
15$ for the T-mount adapter
20$ for the condenser lens
20$ for the macro lens
50$ for misc part (from aluminium tube to glue and black paint)
and you got your mini35 for less than 150$.
I think 100$ is not unrealistic.

Giroud:

Where can I get a $20 condensor lens?

Anyone else, for that matter, would you do me the favor of condensing the condensor lens options? :D If I have to pick one up, I'd like to know: what's best, what's cheapest (aside from fresnels, which I don't want), and what's the best compromise between best quality and lowest price?

Thanks,

- jim

Jim, the condenser I am using is from a Petri Aux Telephoto Lens 1:1.9 4.5cm. I took one lens on the telephoto and it's working perfect for me.

Here is something on Ebay , It's not exactly the same as mine.
Petri Auxiliary wide angle and telephoto lenses for 1:2.8 4.5cm

http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=3801032878&category=29971

http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=3801141877&category=30077

Alain

Whats up Alain. Whats new with your adapter? What do you think about adjustable still photography extention tubes for our adapters casing.

Hi Brett
 

My adapter is done .I am going to start anoter one whit a lens that I have found this weekend for $30, the optic are not good but the tubing a perfect. This thing's gone a be perfect for what your talking about.

Alain

Is it a internal focus lens? They work the best because the only thing that turns on the lens is the focus ring. May I ask what the make and model is?

-B

just a silly question.
we are looking for achromat lens for the macro one, but do we need a condenser with achromat specs, or this not applies to such kind of lens ?

in need of xl1 aldu examples
 

can i please get some pics, tutorials, footage, of any xl1 with this aldu35? what was the cost to make it? how much would you sell one to me for? sorry for not reading this entire thread to see who is developing one for thier xl1 but, after reading the lengthy aguss35 thread, i decided to jump the gun on this one.

Brett
 

Yes ,It's a Rexatar 200mm .There is some modification to do on this but it's a very good piece to start whit.

Alain