If anyone has ever considered making their own lens, but felt it would be beyond their capabilities, this DIY article that was published sometime ago might just change your mind..
It's a very straight forward description of what's required to produce a very reasonable Anamorphic lens..
Anyone with any Carpentry skills should be able to make up the lens box..and the method of setting up the prisms is clearly explained and shown..
There are three axis to consider and whilst X (depth) is variable, Y (width) and Z (height) MUST be aligned correctly or the or the lens won't focus properly and I haven't even mentioned rotation. You might remember I included a paper check test included with the Mk1. This is nothing like this, and the ONLY way to get this correct is to use single display pixel lines that run in both the H and V directions. So the DIY case I am creating will allow all the adjustments and (hopefully) allow you to get the best from the lens in your system.
Not exactly a true DIY job. What I will do this week is draw up all the parts for the laser cutter to run me a prototype. After I have assembled it and worked any bugs out (I have a spare set of optics here for testing purposes), I will be able to start a production run. The end user could assemble this case themselves. The point is that there is a great deal of accuracy required in the design, so why I feel it is best to have all the parts duplicated from a machine rather than having each DIY lens being essentially a one off.
The idea here is to offer an "affordable" solution to a high end problem. The challenge I face is that there seems to be a belief system in place that anything DIY is cheap. This glass used in this lens is not cheap and the cost cutting exercise here is the case where the machined alloy cases are expensive to produce forcing the price of the MK4 up to its listed price. Take that out of the equation and you have a very good product that more could afford.
So each case is machined individually!?..That would be expensive..
Obviously, Injection Moulding would be a lot cheaper, but off course that's only practical with a large quantity of units..I see your dilemma..
The joys of machining. For this case, the most economic way to do the case is to laser cut the plastic parts. That way, the case should be less than $100 each.
Sorry I have been out of touch since my post....We are making a lot of changes at work that had me working all last weekend and very long days this week. Once the dust settles around these servers I will start posting my progress.
I have a few ideas about my case but before I start actually putting anything together I thought I would set them up in front of my PJ to get a feel for where they should sit. I see what Mark is talking about on being VERY precise. This case will have to be very carefully crafted (laser cut plastic might be ideal) or designed or at minimum it will need to have a least 3 fine tuning adjustments to get the lens setup correctly.
This weekend is set to be gorgeous (weather wise) and I hope to get out in the garage open the door and see what I can come up with.
Laser cut plastic is probably the most affordable and accurate method to make the lens holders.
Given the rear lens is some 19mm think, my new DIY case will be made from 2 layers of 10mm (bonded) with a cutout of 80mm in each, and have a 2mm plates front and black (back plate will be bonded, front plate will be screwed down) with a cutout of 76mm. I'll also use the same 76/2mm O Rings that I use in the MK4. This way the lens can't move and is sealed once installed and aligned.
I've been working on this new case for 4 days now and I am still finding things I need to change. Lucky I find it fun to do this stuff.
Ok after about 2 weeks of painstakingly drawing and redrawing this new "DIY lens" case, I finally am ready to take the design to a fabricator to make the prototype. This will probably take another 10~14 days. The reason for this post is simply to let you guys know I am all over this.
Sweet Mark!! Keep me posted......I have been swamped at work...the new building is nearing completion so all of the projects I have been working on are about to be installed...((Video Wall (Qty12 55" screens) access control, distributed audio, audio for Basketball court, gym,fitness room.....)) As fun as it sounds to be able to spend money that is not yours to get some really nice equipment....It can still be stressful!
Let me know when you get that case back from the cutting shop.
Mark..With the case for the Mk. 4 lens.. is it just the spacing and vertical alignment of the lens elements that's critical, or are there other aspects to consider?
Spacing between the lenses as well as alignment of the two lenses. They must be perfectly aligned to each other on all three axis. An issue I identified with batch 1 was that the front lens had a very small degree of movement (part was 0.25mm undersized) that allowed the front lens to yaw. This was enough to prevent the lens from focusing corner to corner. That was fixed in batch 2.
So I have to make sure I don't allow movement in the wrong directions for this project.
As an example of how precise these lenses are, the difference between being able to see inter pixel gaps and not on a 1080P can be a difference of less than 1/8th of a turn of the cap screw on the front of the MK4. It runs on a standard M6 thread.
This sort of precision is more like an SLR camera lens than an A lens!!
Obviously the multi element A lens is closer to a camera lens than the prism type A lenses..
OK I picked up the prototype today and assembled it. Yeah it is a work in progress. I need to go back to my CADs because there are holes that do not line up and a few holes are not on the parts they should be. Easily correctable, just time lost is annoying. All I can say is it is HUGE and looks so cool.
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